From 6462b08a3bda05359ed0753bb6f066ce3f6430f8 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Wed, 13 Jun 2018 14:11:01 +0200
Subject: [PATCH 01/10] Updated logrus dependecy version

---
 glide.lock | 28 ++++++++++++++++------------
 glide.yaml |  2 +-
 2 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/glide.lock b/glide.lock
index b4a845ab..4beaecf5 100644
--- a/glide.lock
+++ b/glide.lock
@@ -1,5 +1,5 @@
-hash: 87b17ae086fd78cf015e658b5438eda33382592c2f193a03b9a41eaeca7dbd59
-updated: 2018-07-13T15:34:55.360455+02:00
+hash: 968e59612847bf5883b44211821e96596282653c6ef6b50c8a3dc85b43d48b58
+updated: 2018-07-24T19:00:32.457031+02:00
 imports:
 - name: cloud.google.com/go
   version: 3b1ae45394a234c385be014e9a488f2bb6eef821
@@ -118,11 +118,15 @@ imports:
 - name: github.com/imdario/mergo
   version: 9316a62528ac99aaecb4e47eadd6dc8aa6533d58
 - name: github.com/json-iterator/go
-  version: 13f86432b882000a51c6e610c620974462691a97
+  version: f2b4162afba35581b6d4a50d3b8f34e33c144682
 - name: github.com/matttproud/golang_protobuf_extensions
   version: fc2b8d3a73c4867e51861bbdd5ae3c1f0869dd6a
   subpackages:
   - pbutil
+- name: github.com/modern-go/concurrent
+  version: bacd9c7ef1dd9b15be4a9909b8ac7a4e313eec94
+- name: github.com/modern-go/reflect2
+  version: 05fbef0ca5da472bbf96c9322b84a53edc03c9fd
 - name: github.com/nats-io/go-nats
   version: d66cb54e6b7bdd93f0b28afc8450d84c780dfb68
   subpackages:
@@ -260,7 +264,7 @@ imports:
   - internal/urlfetch
   - urlfetch
 - name: google.golang.org/genproto
-  version: 09f6ed296fc66555a25fe4ce95173148778dfa85
+  version: f8c8703595236ae70fdf8789ecb656ea0bcdcf46
   subpackages:
   - googleapis/api/annotations
   - googleapis/rpc/status
@@ -298,7 +302,7 @@ imports:
 - name: gopkg.in/yaml.v2
   version: 670d4cfef0544295bc27a114dbac37980d83185a
 - name: k8s.io/api
-  version: 8b7507fac302640dd5f1efbf9643199952cc58db
+  version: 0f11257a8a25954878633ebdc9841c67d8f83bdb
   subpackages:
   - admissionregistration/v1alpha1
   - admissionregistration/v1beta1
@@ -329,7 +333,7 @@ imports:
   - storage/v1alpha1
   - storage/v1beta1
 - name: k8s.io/apiextensions-apiserver
-  version: b13a681559816a9c14f93086bbeeed1c7baf2bcb
+  version: f584b16eb23bd2a3fd292a027d698d95db427c5d
   subpackages:
   - pkg/apis/apiextensions
   - pkg/apis/apiextensions/v1beta1
@@ -337,7 +341,7 @@ imports:
   - pkg/client/clientset/clientset/scheme
   - pkg/client/clientset/clientset/typed/apiextensions/v1beta1
 - name: k8s.io/apimachinery
-  version: f6313580a4d36c7c74a3d845dda6e116642c4f90
+  version: e386b2658ed20923da8cc9250e552f082899a1ee
   subpackages:
   - pkg/api/errors
   - pkg/api/meta
@@ -448,7 +452,7 @@ imports:
   - util/retry
 testImports:
 - name: github.com/Azure/go-ansiterm
-  version: 19f72df4d05d31cbe1c56bfc8045c96babff6c7e
+  version: d6e3b3328b783f23731bc4d058875b0371ff8109
   subpackages:
   - winterm
 - name: github.com/cenkalti/backoff
@@ -458,19 +462,19 @@ testImports:
   subpackages:
   - pathdriver
 - name: github.com/docker/go-connections
-  version: 3ede32e2033de7505e6500d6c868c2b9ed9f169d
+  version: 7395e3f8aa162843a74ed6d48e79627d9792ac55
   subpackages:
   - nat
 - name: github.com/docker/go-units
-  version: 9e638d38cf6977a37a8ea0078f3ee75a7cdb2dd1
+  version: 47565b4f722fb6ceae66b95f853feed578a4a51c
 - name: github.com/Microsoft/go-winio
   version: ab35fc04b6365e8fcb18e6e9e41ea4a02b10b175
 - name: github.com/Nvveen/Gotty
   version: cd527374f1e5bff4938207604a14f2e38a9cf512
 - name: github.com/opencontainers/go-digest
-  version: a6d0ee40d4207ea02364bd3b9e8e77b9159ba1eb
+  version: c9281466c8b2f606084ac71339773efd177436e7
 - name: github.com/opencontainers/image-spec
-  version: 372ad780f63454fbbbbcc7cf80e5b90245c13e13
+  version: e562b04403929d582d449ae5386ff79dd7961a11
   subpackages:
   - specs-go
   - specs-go/v1
diff --git a/glide.yaml b/glide.yaml
index b9b4892c..1b63b6b3 100644
--- a/glide.yaml
+++ b/glide.yaml
@@ -7,7 +7,7 @@ import:
 - package: github.com/fission/fission
   version: ^0.9.1
 - package: github.com/sirupsen/logrus
-  version: ~1.0.4
+  version: v1.0.5
 - package: github.com/urfave/cli
   version: ~1.19.1
 - package: github.com/gorilla/handlers

From d5d35e82ae050f0b11eab9006ffa01bd049ad318 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Wed, 13 Jun 2018 17:29:51 +0200
Subject: [PATCH 02/10] Convert untyped events to typed event messages

---
 pkg/api/invocation.go                   |  84 +++---
 pkg/api/task.go                         |  73 ++---
 pkg/api/workflow.go                     |  37 +--
 pkg/controller/invocation/controller.go |  31 +--
 pkg/fes/backend/mem/mem_test.go         |  37 ++-
 pkg/fes/fes.pb.go                       |  44 +--
 pkg/fes/fes.proto                       |   3 +-
 pkg/fes/util.go                         |  26 +-
 pkg/types/aggregates/aggregates.go      |  15 ++
 pkg/types/aggregates/invocation.go      |  81 ++----
 pkg/types/aggregates/task.go            |  50 +---
 pkg/types/aggregates/workflow.go        |  35 +--
 pkg/types/events/events.pb.go           | 342 +++++++++++++++++-------
 pkg/types/events/events.proto           |  80 ++++--
 pkg/types/events/fsm.go                 |  32 ---
 pkg/types/events/util.go                |  34 ---
 16 files changed, 523 insertions(+), 481 deletions(-)
 create mode 100644 pkg/types/aggregates/aggregates.go
 delete mode 100644 pkg/types/events/fsm.go
 delete mode 100644 pkg/types/events/util.go

diff --git a/pkg/api/invocation.go b/pkg/api/invocation.go
index 12e717f2..06e624ac 100644
--- a/pkg/api/invocation.go
+++ b/pkg/api/invocation.go
@@ -10,8 +10,6 @@ import (
 	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/fission/fission-workflows/pkg/util"
-	"github.com/golang/protobuf/proto"
-	"github.com/golang/protobuf/ptypes"
 )
 
 const ErrInvocationCanceled = "workflow invocation was canceled"
@@ -30,27 +28,25 @@ func NewInvocationAPI(esClient fes.Backend) *Invocation {
 // Invoke triggers the start of the invocation using the provided specification.
 // The function either returns the invocationID of the invocation or an error.
 // The error can be a validate.Err, proto marshall error, or a fes error.
-func (ia *Invocation) Invoke(invocation *types.WorkflowInvocationSpec) (string, error) {
-	err := validate.WorkflowInvocationSpec(invocation)
+func (ia *Invocation) Invoke(spec *types.WorkflowInvocationSpec) (string, error) {
+	err := validate.WorkflowInvocationSpec(spec)
 	if err != nil {
 		return "", err
 	}
 
 	id := fmt.Sprintf("wi-%s", util.UID())
-	data, err := proto.Marshal(invocation)
+
+	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(id), &events.InvocationCreated{
+		Spec: spec,
+	})
 	if err != nil {
 		return "", err
 	}
-
-	err = ia.es.Append(&fes.Event{
-		Type:      events.Invocation_INVOCATION_CREATED.String(),
-		Aggregate: aggregates.NewWorkflowInvocationAggregate(id),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      data,
-	})
+	err = ia.es.Append(event)
 	if err != nil {
 		return "", err
 	}
+
 	return id, nil
 }
 
@@ -62,19 +58,20 @@ func (ia *Invocation) Cancel(invocationID string) error {
 		return validate.NewError("invocationID", errors.New("id should not be empty"))
 	}
 
-	data, err := proto.Marshal(&types.Error{
-		Message: ErrInvocationCanceled,
+	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(invocationID), &events.InvocationCanceled{
+		Error: &types.Error{
+			Message: ErrInvocationCanceled,
+		},
 	})
 	if err != nil {
-		data = []byte{}
+		return err
 	}
-	return ia.es.Append(&fes.Event{
-		Type:      events.Invocation_INVOCATION_CANCELED.String(),
-		Aggregate: aggregates.NewWorkflowInvocationAggregate(invocationID),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      data,
-		Hints:     &fes.EventHints{Completed: true},
-	})
+	event.Hints = &fes.EventHints{Completed: true}
+	err = ia.es.Append(event)
+	if err != nil {
+		return err
+	}
+	return nil
 }
 
 // Complete forces the completion of an invocation. This function - used by the controller - is the only way
@@ -85,20 +82,14 @@ func (ia *Invocation) Complete(invocationID string, output *types.TypedValue) er
 		return validate.NewError("invocationID", errors.New("id should not be empty"))
 	}
 
-	data, err := proto.Marshal(&types.WorkflowInvocationStatus{
+	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(invocationID), &events.InvocationCompleted{
 		Output: output,
 	})
 	if err != nil {
 		return err
 	}
-
-	return ia.es.Append(&fes.Event{
-		Type:      events.Invocation_INVOCATION_COMPLETED.String(),
-		Aggregate: aggregates.NewWorkflowInvocationAggregate(invocationID),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      data,
-		Hints:     &fes.EventHints{Completed: true},
-	})
+	event.Hints = &fes.EventHints{Completed: true}
+	return ia.es.Append(event)
 }
 
 // Fail changes the state of the invocation to FAILED.
@@ -110,22 +101,19 @@ func (ia *Invocation) Fail(invocationID string, errMsg error) error {
 	}
 
 	var msg string
-	if errMsg != nil {
+	if errMsg == nil {
 		msg = errMsg.Error()
 	}
-	data, err := proto.Marshal(&types.Error{
-		Message: msg,
+	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(invocationID), &events.InvocationFailed{
+		Error: &types.Error{
+			Message: msg,
+		},
 	})
 	if err != nil {
-		data = []byte{}
+		return err
 	}
-	return ia.es.Append(&fes.Event{
-		Type:      events.Invocation_INVOCATION_FAILED.String(),
-		Aggregate: aggregates.NewWorkflowInvocationAggregate(invocationID),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      data,
-		Hints:     &fes.EventHints{Completed: true},
-	})
+	event.Hints = &fes.EventHints{Completed: true}
+	return ia.es.Append(event)
 }
 
 // AddTask provides functionality to add a task to a specific invocation (instead of a workflow).
@@ -140,15 +128,11 @@ func (ia *Invocation) AddTask(invocationID string, task *types.Task) error {
 		return err
 	}
 
-	data, err := proto.Marshal(task)
+	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(invocationID), &events.InvocationTaskAdded{
+		Task: task,
+	})
 	if err != nil {
 		return err
 	}
-
-	return ia.es.Append(&fes.Event{
-		Type:      events.Invocation_INVOCATION_TASK_ADDED.String(),
-		Aggregate: aggregates.NewWorkflowInvocationAggregate(invocationID),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      data,
-	})
+	return ia.es.Append(event)
 }
diff --git a/pkg/api/task.go b/pkg/api/task.go
index d6f6e8b7..511908d6 100644
--- a/pkg/api/task.go
+++ b/pkg/api/task.go
@@ -10,7 +10,6 @@ import (
 	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/types/typedvalues"
 	"github.com/fission/fission-workflows/pkg/types/validate"
-	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
 	"github.com/sirupsen/logrus"
 )
@@ -44,7 +43,7 @@ func (ap *Task) Invoke(spec *types.TaskInvocationSpec) (*types.TaskInvocation, e
 	}
 
 	taskID := spec.TaskId // assumption: 1 task == 1 TaskInvocation (How to deal with retries? Same invocation?)
-	fn := &types.TaskInvocation{
+	task := &types.TaskInvocation{
 		Metadata: &types.ObjectMetadata{
 			Id:        taskID,
 			CreatedAt: ptypes.TimestampNow(),
@@ -52,19 +51,14 @@ func (ap *Task) Invoke(spec *types.TaskInvocationSpec) (*types.TaskInvocation, e
 		Spec: spec,
 	}
 
-	fnAny, err := proto.Marshal(fn)
+	aggregate := aggregates.NewWorkflowInvocationAggregate(spec.InvocationId)
+	event, err := fes.NewEvent(*aggregates.NewTaskInvocationAggregate(taskID), &events.TaskStarted{
+		Task: task,
+	})
+	event.Parent = aggregate
 	if err != nil {
 		return nil, err
 	}
-
-	aggregate := aggregates.NewWorkflowInvocationAggregate(spec.InvocationId)
-	err = ap.es.Append(&fes.Event{
-		Type:      events.Task_TASK_STARTED.String(),
-		Parent:    aggregate,
-		Aggregate: aggregates.NewTaskInvocationAggregate(taskID),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      fnAny,
-	})
 	if err != nil {
 		return nil, err
 	}
@@ -75,17 +69,11 @@ func (ap *Task) Invoke(spec *types.TaskInvocationSpec) (*types.TaskInvocation, e
 	}
 	if err != nil {
 		// TODO improve error handling here (retries? internal or task related error?)
-		logrus.WithField("fn", spec.FnRef).
+		logrus.WithField("task", spec.FnRef).
 			WithField("wi", spec.InvocationId).
 			WithField("task", spec.TaskId).
 			Infof("Failed to invoke task: %v", err)
-		esErr := ap.es.Append(&fes.Event{
-			Type:      events.Task_TASK_FAILED.String(),
-			Parent:    aggregate,
-			Aggregate: aggregates.NewTaskInvocationAggregate(taskID),
-			Timestamp: ptypes.TimestampNow(),
-			Data:      fnAny,
-		})
+		esErr := ap.Fail(spec.InvocationId, taskID, err.Error())
 		if esErr != nil {
 			return nil, esErr
 		}
@@ -105,40 +93,29 @@ func (ap *Task) Invoke(spec *types.TaskInvocationSpec) (*types.TaskInvocation, e
 		}
 	}
 
-	fn.Status = fnResult
-	fnStatusAny, err := proto.Marshal(fn)
-	if err != nil {
-		return nil, err
-	}
-
 	if fnResult.Status == types.TaskInvocationStatus_SUCCEEDED {
-		err = ap.es.Append(&fes.Event{
-			Type:      events.Task_TASK_SUCCEEDED.String(),
-			Parent:    aggregate,
-			Aggregate: aggregates.NewTaskInvocationAggregate(taskID),
-			Timestamp: ptypes.TimestampNow(),
-			Data:      fnStatusAny,
+		event, err := fes.NewEvent(*aggregates.NewTaskInvocationAggregate(taskID), &events.TaskSucceeded{
+			Result: fnResult,
 		})
+		if err != nil {
+			return nil, err
+		}
+		event.Parent = aggregate
+		err = ap.es.Append(event)
 	} else {
-		err = ap.es.Append(&fes.Event{
-			Type:      events.Task_TASK_FAILED.String(),
-			Parent:    aggregate,
-			Aggregate: aggregates.NewTaskInvocationAggregate(taskID),
-			Timestamp: ptypes.TimestampNow(),
-			Data:      fnStatusAny,
-		})
+		err = ap.Fail(spec.InvocationId, taskID, fnResult.Error.GetMessage())
 	}
 	if err != nil {
 		return nil, err
 	}
 
-	fn.Status = fnResult
-	return fn, nil
+	task.Status = fnResult
+	return task, nil
 }
 
 // Fail forces the failure of a task. This turns the state of a task into FAILED.
 // If the API fails to append the event to the event store, it will return an error.
-func (ap *Task) Fail(invocationID string, taskID string) error {
+func (ap *Task) Fail(invocationID string, taskID string, errMsg string) error {
 	if len(invocationID) == 0 {
 		return validate.NewError("invocationID", errors.New("id should not be empty"))
 	}
@@ -146,10 +123,12 @@ func (ap *Task) Fail(invocationID string, taskID string) error {
 		return validate.NewError("taskID", errors.New("id should not be empty"))
 	}
 
-	return ap.es.Append(&fes.Event{
-		Type:      events.Task_TASK_FAILED.String(),
-		Parent:    aggregates.NewWorkflowInvocationAggregate(invocationID),
-		Aggregate: aggregates.NewTaskInvocationAggregate(taskID),
-		Timestamp: ptypes.TimestampNow(),
+	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(invocationID), &events.TaskFailed{
+		Error: &types.Error{Message: errMsg},
 	})
+	if err != nil {
+		return err
+	}
+	event.Parent = aggregates.NewWorkflowInvocationAggregate(invocationID)
+	return ap.es.Append(event)
 }
diff --git a/pkg/api/workflow.go b/pkg/api/workflow.go
index de40c00c..7fbd08a6 100644
--- a/pkg/api/workflow.go
+++ b/pkg/api/workflow.go
@@ -11,7 +11,6 @@ import (
 	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/fission/fission-workflows/pkg/util"
-	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
 )
 
@@ -43,17 +42,13 @@ func (wa *Workflow) Create(workflow *types.WorkflowSpec) (string, error) {
 		id = fmt.Sprintf("wf-%s", util.UID())
 	}
 
-	data, err := proto.Marshal(workflow)
+	event, err := fes.NewEvent(*aggregates.NewWorkflowAggregate(id), &events.WorkflowCreated{
+		Spec: workflow,
+	})
 	if err != nil {
 		return "", err
 	}
-
-	err = wa.es.Append(&fes.Event{
-		Type:      events.Workflow_WORKFLOW_CREATED.String(),
-		Aggregate: aggregates.NewWorkflowAggregate(id),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      data,
-	})
+	err = wa.es.Append(event)
 	if err != nil {
 		return "", err
 	}
@@ -69,12 +64,12 @@ func (wa *Workflow) Delete(workflowID string) error {
 		return validate.NewError("workflowID", errors.New("id should not be empty"))
 	}
 
-	return wa.es.Append(&fes.Event{
-		Type:      events.Workflow_WORKFLOW_DELETED.String(),
-		Aggregate: aggregates.NewWorkflowAggregate(workflowID),
-		Timestamp: ptypes.TimestampNow(),
-		Hints:     &fes.EventHints{Completed: true},
-	})
+	event, err := fes.NewEvent(*aggregates.NewWorkflowAggregate(workflowID), &events.WorkflowDeleted{})
+	if err != nil {
+		return err
+	}
+	event.Hints = &fes.EventHints{Completed: true}
+	return wa.es.Append(event)
 }
 
 // Parse processes the workflow to resolve any ambiguity.
@@ -100,17 +95,13 @@ func (wa *Workflow) Parse(workflow *types.Workflow) (*types.WorkflowStatus, erro
 		})
 	}
 
-	parsedData, err := proto.Marshal(wfStatus)
+	event, err := fes.NewEvent(*aggregates.NewWorkflowAggregate(workflow.ID()), &events.WorkflowParsed{
+		Tasks: wfStatus.GetTasks(),
+	})
 	if err != nil {
 		return nil, err
 	}
-
-	err = wa.es.Append(&fes.Event{
-		Type:      events.Workflow_WORKFLOW_PARSED.String(),
-		Aggregate: aggregates.NewWorkflowAggregate(workflow.Metadata.Id),
-		Timestamp: ptypes.TimestampNow(),
-		Data:      parsedData,
-	})
+	err = wa.es.Append(event)
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/controller/invocation/controller.go b/pkg/controller/invocation/controller.go
index 90f729a7..3c784eba 100644
--- a/pkg/controller/invocation/controller.go
+++ b/pkg/controller/invocation/controller.go
@@ -12,7 +12,6 @@ import (
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/scheduler"
 	"github.com/fission/fission-workflows/pkg/types/aggregates"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/util/labels"
 	"github.com/fission/fission-workflows/pkg/util/pubsub"
 	"github.com/golang/protobuf/ptypes"
@@ -153,33 +152,11 @@ func (cr *Controller) Notify(msg *fes.Notification) error {
 		"labels":       msg.Labels(),
 	}).Debug("Handling invocation notification!")
 
-	switch msg.EventType {
-	case events.Invocation_INVOCATION_COMPLETED.String():
-		fallthrough
-	case events.Invocation_INVOCATION_CANCELED.String():
-		fallthrough
-	case events.Invocation_INVOCATION_FAILED.String():
-		wfi, ok := msg.Payload.(*aggregates.WorkflowInvocation)
-		if !ok {
-			log.Warn("Event did not contain invocation payload", msg)
-		}
-		// TODO mark to clean up later instead
-		cr.stateStore.Delete(wfi.ID())
-		cr.evalCache.Del(wfi.ID())
-		log.Infof("Removed invocation %v from eval state", wfi.ID())
-	case events.Task_TASK_FAILED.String():
-		fallthrough
-	case events.Task_TASK_SUCCEEDED.String():
-		fallthrough
-	case events.Invocation_INVOCATION_CREATED.String():
-		wfi, ok := msg.Payload.(*aggregates.WorkflowInvocation)
-		if !ok {
-			panic(msg)
-		}
-		cr.submitEval(wfi.ID())
-	default:
-		wfiLog.Debugf("Controller ignored event type: %v", msg.EventType)
+	wfi, ok := msg.Payload.(*aggregates.WorkflowInvocation)
+	if !ok {
+		panic(msg)
 	}
+	cr.submitEval(wfi.ID())
 	return nil
 }
 
diff --git a/pkg/fes/backend/mem/mem_test.go b/pkg/fes/backend/mem/mem_test.go
index b7fa4d9b..2b4d5181 100644
--- a/pkg/fes/backend/mem/mem_test.go
+++ b/pkg/fes/backend/mem/mem_test.go
@@ -6,31 +6,48 @@ import (
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/util/labels"
 	"github.com/fission/fission-workflows/pkg/util/pubsub"
+	"github.com/golang/protobuf/ptypes/wrappers"
 	"github.com/stretchr/testify/assert"
 )
 
+func newEvent(a fes.Aggregate, data []byte) *fes.Event {
+	event, err := fes.NewEvent(a, &wrappers.BytesValue{
+		Value: data,
+	})
+	if err != nil {
+		panic(err)
+	}
+	return event
+}
+
 func TestBackend_Append(t *testing.T) {
 	mem := NewBackend()
 
-	event := fes.NewEvent(fes.NewAggregate("type", "id"), []byte("event 1"))
+	event := newEvent(fes.NewAggregate("type", "id"), []byte("event 1"))
 	err := mem.Append(event)
 	assert.NoError(t, err)
 	assert.Len(t, mem.contents, 1)
 
-	event2 := fes.NewEvent(fes.Aggregate{}, []byte("event 1"))
+	event2 := newEvent(fes.Aggregate{}, []byte("event 1"))
 	err = mem.Append(event2)
 	assert.EqualError(t, err, ErrInvalidAggregate.Error())
 	assert.Len(t, mem.contents, 1)
 
 	// Event under existing aggregate
-	event3 := fes.NewEvent(fes.NewAggregate("type", "id"), []byte("event 2"))
+	event3, err := fes.NewEvent(fes.NewAggregate("type", "id"), &wrappers.BytesValue{
+		Value: []byte("event 2"),
+	})
+	assert.NoError(t, err)
 	err = mem.Append(event3)
 	assert.NoError(t, err)
 	assert.Len(t, mem.contents, 1)
 	assert.Len(t, mem.contents[fes.NewAggregate("type", "id")], 2)
 
 	// Event under new aggregate
-	event4 := fes.NewEvent(fes.NewAggregate("Type", "other"), []byte("event 1"))
+	event4, err := fes.NewEvent(fes.NewAggregate("Type", "other"), &wrappers.BytesValue{
+		Value: []byte("event 1"),
+	})
+	assert.NoError(t, err)
 	err = mem.Append(event4)
 	assert.NoError(t, err)
 	assert.Len(t, mem.contents, 2)
@@ -42,9 +59,9 @@ func TestBackend_GetMultiple(t *testing.T) {
 	mem := NewBackend()
 	key := fes.NewAggregate("type", "id")
 	events := []*fes.Event{
-		fes.NewEvent(key, []byte("event 1")),
-		fes.NewEvent(key, []byte("event 2")),
-		fes.NewEvent(key, []byte("event 3")),
+		newEvent(key, []byte("event 1")),
+		newEvent(key, []byte("event 2")),
+		newEvent(key, []byte("event 3")),
 	}
 
 	for k := range events {
@@ -73,9 +90,9 @@ func TestBackend_Subscribe(t *testing.T) {
 	})
 
 	events := []*fes.Event{
-		fes.NewEvent(key, []byte("event 1")),
-		fes.NewEvent(key, []byte("event 2")),
-		fes.NewEvent(key, []byte("event 3")),
+		newEvent(key, []byte("event 1")),
+		newEvent(key, []byte("event 2")),
+		newEvent(key, []byte("event 3")),
 	}
 	for k := range events {
 		err := mem.Append(events[k])
diff --git a/pkg/fes/fes.pb.go b/pkg/fes/fes.pb.go
index 00809f23..999acf26 100644
--- a/pkg/fes/fes.pb.go
+++ b/pkg/fes/fes.pb.go
@@ -18,6 +18,7 @@ import proto "github.com/golang/protobuf/proto"
 import fmt "fmt"
 import math "math"
 import google_protobuf "github.com/golang/protobuf/ptypes/timestamp"
+import google_protobuf1 "github.com/golang/protobuf/ptypes/any"
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -59,7 +60,7 @@ type Event struct {
 	Type      string                     `protobuf:"bytes,2,opt,name=type" json:"type,omitempty"`
 	Aggregate *Aggregate                 `protobuf:"bytes,3,opt,name=aggregate" json:"aggregate,omitempty"`
 	Timestamp *google_protobuf.Timestamp `protobuf:"bytes,4,opt,name=timestamp" json:"timestamp,omitempty"`
-	Data      []byte                     `protobuf:"bytes,5,opt,name=data,proto3" json:"data,omitempty"`
+	Data      *google_protobuf1.Any      `protobuf:"bytes,5,opt,name=data" json:"data,omitempty"`
 	Parent    *Aggregate                 `protobuf:"bytes,6,opt,name=parent" json:"parent,omitempty"`
 	Hints     *EventHints                `protobuf:"bytes,7,opt,name=hints" json:"hints,omitempty"`
 }
@@ -97,7 +98,7 @@ func (m *Event) GetTimestamp() *google_protobuf.Timestamp {
 	return nil
 }
 
-func (m *Event) GetData() []byte {
+func (m *Event) GetData() *google_protobuf1.Any {
 	if m != nil {
 		return m.Data
 	}
@@ -144,23 +145,24 @@ func init() {
 func init() { proto.RegisterFile("pkg/fes/fes.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
-	// 280 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x94, 0x90, 0x41, 0x4b, 0xfc, 0x30,
-	0x10, 0xc5, 0x69, 0x77, 0xbb, 0xff, 0x7f, 0x47, 0x11, 0xcc, 0x29, 0x2c, 0x0b, 0x2e, 0xbd, 0x58,
-	0x3c, 0xa4, 0xa0, 0x17, 0x4f, 0x8a, 0xc2, 0x82, 0xe7, 0xe0, 0xc9, 0x5b, 0xd6, 0x4e, 0x63, 0xd8,
-	0xb6, 0x09, 0xcd, 0xe8, 0xe2, 0xc7, 0xf3, 0x9b, 0x49, 0x53, 0xbb, 0xbd, 0x2d, 0x7a, 0x08, 0x0c,
-	0x8f, 0xf7, 0x9b, 0xbc, 0x37, 0x70, 0xee, 0x76, 0xba, 0xa8, 0xd0, 0xf7, 0x4f, 0xb8, 0xce, 0x92,
-	0x65, 0xab, 0xca, 0x78, 0x6f, 0x6c, 0x2b, 0xf6, 0xb6, 0xdb, 0x55, 0xb5, 0xdd, 0x7b, 0x81, 0x1f,
-	0xd8, 0x92, 0x27, 0xdb, 0xe1, 0xf2, 0x42, 0x5b, 0xab, 0x6b, 0x2c, 0x82, 0x77, 0xfb, 0x5e, 0x15,
-	0x64, 0x1a, 0xf4, 0xa4, 0x1a, 0x37, 0xe0, 0x59, 0x01, 0xe9, 0x83, 0xd6, 0x1d, 0x6a, 0x45, 0xc8,
-	0xce, 0x20, 0x36, 0x25, 0x8f, 0xd6, 0x51, 0x9e, 0xca, 0xd8, 0x94, 0x8c, 0xc1, 0x9c, 0x3e, 0x1d,
-	0xf2, 0x38, 0x28, 0x61, 0xce, 0xbe, 0x62, 0x48, 0x36, 0xfd, 0x07, 0xbf, 0x71, 0xb3, 0x0d, 0xa4,
-	0x6a, 0x5c, 0xcf, 0x67, 0xeb, 0x28, 0x3f, 0xb9, 0xbe, 0x14, 0xc7, 0x12, 0x8b, 0x43, 0x1a, 0x39,
-	0x91, 0xec, 0x16, 0xd2, 0x43, 0x70, 0x3e, 0x0f, 0x6b, 0x96, 0x62, 0xa8, 0x26, 0xc6, 0x6a, 0xe2,
-	0x79, 0x74, 0xc8, 0xc9, 0xdc, 0x87, 0x2a, 0x15, 0x29, 0x9e, 0xac, 0xa3, 0xfc, 0x54, 0x86, 0x99,
-	0xdd, 0xc3, 0xc2, 0xa9, 0x0e, 0x5b, 0xe2, 0x8b, 0xbf, 0x25, 0xfa, 0xc1, 0xd8, 0x1d, 0x24, 0x6f,
-	0xa6, 0x25, 0xcf, 0xff, 0x05, 0x3e, 0x3f, 0xce, 0x87, 0x6b, 0x3d, 0xf5, 0x7e, 0x39, 0x60, 0xd9,
-	0x15, 0xc0, 0x24, 0xb2, 0x15, 0xa4, 0xaf, 0xb6, 0x71, 0x35, 0x12, 0x0e, 0xe7, 0xfc, 0x2f, 0x27,
-	0xe1, 0x31, 0x79, 0x99, 0x55, 0xe8, 0xb7, 0x8b, 0x50, 0xf3, 0xe6, 0x3b, 0x00, 0x00, 0xff, 0xff,
-	0x09, 0xe1, 0x0f, 0x3d, 0x02, 0x02, 0x00, 0x00,
+	// 293 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x94, 0x90, 0x41, 0x4b, 0xc3, 0x30,
+	0x14, 0xc7, 0x59, 0xb7, 0x4e, 0xfb, 0x04, 0xc1, 0xe0, 0x21, 0x8e, 0x81, 0x63, 0x17, 0x8b, 0x87,
+	0x14, 0xf4, 0xe2, 0x49, 0x99, 0x30, 0xf0, 0x1c, 0x3c, 0x79, 0xcb, 0xec, 0x6b, 0x0c, 0x6b, 0x93,
+	0xd0, 0x44, 0x47, 0x3f, 0xa9, 0x5f, 0x47, 0x9a, 0xda, 0x15, 0x14, 0x86, 0x1e, 0x02, 0xe1, 0xe5,
+	0xf7, 0x7b, 0x79, 0xff, 0x07, 0x67, 0x76, 0x2b, 0xb3, 0x02, 0x5d, 0x7b, 0x98, 0xad, 0x8d, 0x37,
+	0x64, 0x5e, 0x28, 0xe7, 0x94, 0xd1, 0x6c, 0x67, 0xea, 0x6d, 0x51, 0x9a, 0x9d, 0x63, 0xf8, 0x81,
+	0xda, 0x3b, 0x6f, 0x6a, 0x9c, 0x5d, 0x4a, 0x63, 0x64, 0x89, 0x59, 0x60, 0x37, 0xef, 0x45, 0xe6,
+	0x55, 0x85, 0xce, 0x8b, 0xca, 0x76, 0xfa, 0xec, 0xe2, 0x27, 0x20, 0x74, 0xd3, 0x3d, 0x2d, 0x33,
+	0x48, 0x56, 0x52, 0xd6, 0x28, 0x85, 0x47, 0x72, 0x0a, 0x91, 0xca, 0xe9, 0x68, 0x31, 0x4a, 0x13,
+	0x1e, 0xa9, 0x9c, 0x10, 0x98, 0xf8, 0xc6, 0x22, 0x8d, 0x42, 0x25, 0xdc, 0x97, 0x9f, 0x11, 0xc4,
+	0xeb, 0xf6, 0xef, 0xbf, 0xd0, 0x64, 0x0d, 0x89, 0xe8, 0xdb, 0xd3, 0xf1, 0x62, 0x94, 0x9e, 0xdc,
+	0x5c, 0xb1, 0x43, 0x61, 0xd8, 0x7e, 0x1a, 0x3e, 0x98, 0xe4, 0x0e, 0x92, 0x7d, 0x26, 0x3a, 0x09,
+	0x6d, 0x66, 0xac, 0x0b, 0xc5, 0xfa, 0x50, 0xec, 0xb9, 0x27, 0xf8, 0x00, 0x93, 0x14, 0x26, 0xb9,
+	0xf0, 0x82, 0xc6, 0x41, 0x3a, 0xff, 0x25, 0xad, 0x74, 0xc3, 0x03, 0x41, 0x1e, 0x60, 0x6a, 0x45,
+	0x8d, 0xda, 0xd3, 0xe9, 0xff, 0xe6, 0xfc, 0xd6, 0xc8, 0x3d, 0xc4, 0x6f, 0x4a, 0x7b, 0x47, 0x8f,
+	0x82, 0x9f, 0x1e, 0xf6, 0xc3, 0x0e, 0x9f, 0x5a, 0x9e, 0x77, 0xda, 0xf2, 0x1a, 0x60, 0x28, 0x92,
+	0x39, 0x24, 0xaf, 0xa6, 0xb2, 0x25, 0x7a, 0xec, 0x96, 0x7c, 0xcc, 0x87, 0xc2, 0x63, 0xfc, 0x32,
+	0x2e, 0xd0, 0x6d, 0xa6, 0x21, 0xc7, 0xed, 0x57, 0x00, 0x00, 0x00, 0xff, 0xff, 0xce, 0x60, 0xbf,
+	0x26, 0x33, 0x02, 0x00, 0x00,
 }
diff --git a/pkg/fes/fes.proto b/pkg/fes/fes.proto
index d085e0fa..fbfa2c0d 100644
--- a/pkg/fes/fes.proto
+++ b/pkg/fes/fes.proto
@@ -4,6 +4,7 @@ package fission.workflows.eventstore;
 option go_package = "fes";
 
 import "google/protobuf/timestamp.proto";
+import "google/protobuf/any.proto";
 
 message Aggregate {
     string id = 1;
@@ -15,7 +16,7 @@ message Event {
     string type = 2;
     Aggregate aggregate = 3;
     google.protobuf.Timestamp timestamp = 4;
-    bytes data = 5;
+    google.protobuf.Any data = 5;
     Aggregate parent = 6;
     EventHints hints = 7;
 }
diff --git a/pkg/fes/util.go b/pkg/fes/util.go
index eb7fb0cb..89bcd07e 100644
--- a/pkg/fes/util.go
+++ b/pkg/fes/util.go
@@ -2,9 +2,13 @@ package fes
 
 import (
 	"errors"
+	"reflect"
 	"strings"
+	"time"
 
+	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
+	"github.com/golang/protobuf/ptypes/any"
 )
 
 func validateAggregate(aggregate Aggregate) error {
@@ -42,13 +46,25 @@ func NewAggregate(entityType string, entityID string) Aggregate {
 	}
 }
 
-func NewEvent(aggregate Aggregate, data []byte) *Event {
+type EventOpts struct {
+	Event
+	Data      proto.Message
+	Timestamp time.Time
+}
+
+func NewEvent(aggregate Aggregate, msg proto.Message) (*Event, error) {
+	var data *any.Any
+	if msg != nil {
+		d, err := ptypes.MarshalAny(msg)
+		if err != nil {
+			return nil, err
+		}
+		data = d
+	}
 	return &Event{
-		Type:      aggregate.Type,
 		Aggregate: &aggregate,
 		Data:      data,
 		Timestamp: ptypes.TimestampNow(),
-		Parent:    nil,
-		Hints:     nil,
-	}
+		Type:      reflect.Indirect(reflect.ValueOf(msg)).Type().Name(),
+	}, nil
 }
diff --git a/pkg/types/aggregates/aggregates.go b/pkg/types/aggregates/aggregates.go
new file mode 100644
index 00000000..a24eb6ca
--- /dev/null
+++ b/pkg/types/aggregates/aggregates.go
@@ -0,0 +1,15 @@
+package aggregates
+
+import (
+	"github.com/fission/fission-workflows/pkg/fes"
+	"github.com/golang/protobuf/ptypes"
+)
+
+func unmarshalEventData(event *fes.Event) (interface{}, error) {
+	d := &ptypes.DynamicAny{}
+	err := ptypes.UnmarshalAny(event.Data, d)
+	if err != nil {
+		return nil, err
+	}
+	return d.Message, nil
+}
diff --git a/pkg/types/aggregates/invocation.go b/pkg/types/aggregates/invocation.go
index d475734d..21eed9d3 100644
--- a/pkg/types/aggregates/invocation.go
+++ b/pkg/types/aggregates/invocation.go
@@ -2,7 +2,6 @@ package aggregates
 
 import (
 	"errors"
-	"fmt"
 
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
@@ -38,32 +37,25 @@ func NewWorkflowInvocationAggregate(invocationID string) *fes.Aggregate {
 }
 
 func (wi *WorkflowInvocation) ApplyEvent(event *fes.Event) error {
-	// If the event is a function event, use the Function Aggregate to resolve it.
+	// If the event is a task event, use the Task Aggregate to resolve it.
 	if event.Aggregate.Type == TypeTaskInvocation {
 		return wi.applyTaskEvent(event)
 	}
 
-	// Otherwise assume that this is a invocation event
-	eventType, err := events.ParseInvocation(event.Type)
+	eventData, err := unmarshalEventData(event)
 	if err != nil {
 		return err
 	}
 
-	switch eventType {
-	case events.Invocation_INVOCATION_CREATED:
-		spec := &types.WorkflowInvocationSpec{}
-		err := proto.Unmarshal(event.Data, spec)
-		if err != nil {
-			return fmt.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-		}
-
+	switch m := eventData.(type) {
+	case *events.InvocationCreated:
 		wi.AggregatorMixin = fes.NewAggregatorMixin(wi, *event.Aggregate)
 		wi.WorkflowInvocation = &types.WorkflowInvocation{
 			Metadata: &types.ObjectMetadata{
 				Id:        event.Aggregate.Id,
 				CreatedAt: event.Timestamp,
 			},
-			Spec: spec,
+			Spec: m.GetSpec(),
 			Status: &types.WorkflowInvocationStatus{
 				Status:       types.WorkflowInvocationStatus_IN_PROGRESS,
 				Tasks:        map[string]*types.TaskInvocation{},
@@ -71,43 +63,31 @@ func (wi *WorkflowInvocation) ApplyEvent(event *fes.Event) error {
 				DynamicTasks: map[string]*types.Task{},
 			},
 		}
-	case events.Invocation_INVOCATION_CANCELED:
-		ivErr := &types.Error{}
-		err := proto.Unmarshal(event.Data, ivErr)
-		if err != nil {
-			ivErr.Message = err.Error()
-			log.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-		}
-
+	case *events.InvocationCanceled:
 		wi.Status.Status = types.WorkflowInvocationStatus_ABORTED
 		wi.Status.UpdatedAt = event.GetTimestamp()
-		wi.Status.Error = ivErr
-	case events.Invocation_INVOCATION_COMPLETED:
-		status := &types.WorkflowInvocationStatus{}
-		err = proto.Unmarshal(event.Data, status)
-		if err != nil {
-			return fmt.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-		}
-
+		wi.Status.Error = m.GetError()
+	case *events.InvocationCompleted:
 		if wi.Status == nil {
 			wi.Status = &types.WorkflowInvocationStatus{}
 		}
 
 		wi.Status.Status = types.WorkflowInvocationStatus_SUCCEEDED
-		wi.Status.Output = status.Output
+		wi.Status.Output = m.GetOutput()
 		wi.Status.UpdatedAt = event.GetTimestamp()
-	case events.Invocation_INVOCATION_TASK_ADDED:
-		err := wi.handleTaskAdded(event)
-		if err != nil {
-			return err
+	case *events.InvocationTaskAdded:
+		task := m.GetTask()
+		if wi.Status.DynamicTasks == nil {
+			wi.Status.DynamicTasks = map[string]*types.Task{}
 		}
-	case events.Invocation_INVOCATION_FAILED:
-		errMsg := &types.Error{}
-		err = proto.Unmarshal(event.Data, errMsg)
-		if err != nil {
-			return fmt.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-		}
-		wi.Status.Error = errMsg
+		wi.Status.DynamicTasks[task.ID()] = task
+
+		log.WithFields(log.Fields{
+			"id":          task.ID(),
+			"functionRef": task.Spec.FunctionRef,
+		}).Debug("Added dynamic task.")
+	case *events.InvocationFailed:
+		wi.Status.Error = m.GetError()
 		wi.Status.Status = types.WorkflowInvocationStatus_FAILED
 	default:
 		log.WithFields(log.Fields{
@@ -140,25 +120,6 @@ func (wi *WorkflowInvocation) applyTaskEvent(event *fes.Event) error {
 	return nil
 }
 
-// TODO move updates to other nodes here instead of calculating in graph
-func (wi *WorkflowInvocation) handleTaskAdded(event *fes.Event) error {
-	task := &types.Task{}
-	err := proto.Unmarshal(event.Data, task)
-	if err != nil {
-		return fmt.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-	}
-	if wi.Status.DynamicTasks == nil {
-		wi.Status.DynamicTasks = map[string]*types.Task{}
-	}
-	wi.Status.DynamicTasks[task.ID()] = task
-
-	log.WithFields(log.Fields{
-		"id":          task.ID(),
-		"functionRef": task.Spec.FunctionRef,
-	}).Debug("Added dynamic task.")
-	return nil
-}
-
 func (wi *WorkflowInvocation) GenericCopy() fes.Aggregator {
 	n := &WorkflowInvocation{
 		WorkflowInvocation: wi.Copy(),
diff --git a/pkg/types/aggregates/task.go b/pkg/types/aggregates/task.go
index 3c4216c9..559b22db 100644
--- a/pkg/types/aggregates/task.go
+++ b/pkg/types/aggregates/task.go
@@ -1,8 +1,6 @@
 package aggregates
 
 import (
-	"fmt"
-
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
 	"github.com/fission/fission-workflows/pkg/types/events"
@@ -38,55 +36,35 @@ func NewTaskInvocationAggregate(id string) *fes.Aggregate {
 
 func (ti *TaskInvocation) ApplyEvent(event *fes.Event) error {
 
-	eventType, err := events.ParseTask(event.Type)
+	eventData, err := unmarshalEventData(event)
 	if err != nil {
 		return err
 	}
 
-	switch eventType {
-	case events.Task_TASK_STARTED:
-		fn := &types.TaskInvocation{}
-		err = proto.Unmarshal(event.Data, fn)
-		if err != nil {
-			return fmt.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-		}
-
+	switch m := eventData.(type) {
+	case *events.TaskStarted:
+		task := m.GetTask()
 		ti.TaskInvocation = &types.TaskInvocation{
-			Metadata: fn.Metadata,
-			Spec:     fn.Spec,
+			Metadata: task.GetMetadata(),
+			Spec:     task.GetSpec(),
 			Status: &types.TaskInvocationStatus{
 				Status:    types.TaskInvocationStatus_IN_PROGRESS,
 				UpdatedAt: event.Timestamp,
 			},
 		}
-	case events.Task_TASK_SUCCEEDED:
-		invoc := &types.TaskInvocation{}
-		err = proto.Unmarshal(event.Data, invoc)
-		if err != nil {
-			return fmt.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-		}
-
-		ti.Status.Output = invoc.Status.Output
+	case *events.TaskSucceeded:
+		ti.Status.Output = m.GetResult().Output
 		ti.Status.Status = types.TaskInvocationStatus_SUCCEEDED
 		ti.Status.UpdatedAt = event.Timestamp
-	case events.Task_TASK_ABORTED:
-		ti.Status.Status = types.TaskInvocationStatus_ABORTED
-		ti.Status.UpdatedAt = event.Timestamp
-	case events.Task_TASK_FAILED:
-		if event.Data != nil {
-			invoc := &types.TaskInvocation{}
-			err = proto.Unmarshal(event.Data, invoc)
-			if err != nil {
-				log.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-			}
-			if ti.Status == nil {
-				ti.Status = &types.TaskInvocationStatus{}
-			}
-			ti.Status.Error = invoc.GetStatus().GetError()
+	case *events.TaskFailed:
+		// TODO validate event data
+		if ti.Status == nil {
+			ti.Status = &types.TaskInvocationStatus{}
 		}
+		ti.Status.Error = m.GetError()
 		ti.Status.UpdatedAt = event.Timestamp
 		ti.Status.Status = types.TaskInvocationStatus_FAILED
-	case events.Task_TASK_SKIPPED:
+	case *events.TaskSkipped:
 		ti.Status.Status = types.TaskInvocationStatus_SKIPPED
 		ti.Status.UpdatedAt = event.Timestamp
 	default:
diff --git a/pkg/types/aggregates/workflow.go b/pkg/types/aggregates/workflow.go
index 220e3f3e..2ef7f711 100644
--- a/pkg/types/aggregates/workflow.go
+++ b/pkg/types/aggregates/workflow.go
@@ -35,29 +35,17 @@ func NewWorkflowAggregate(workflowID string) *fes.Aggregate {
 }
 
 func (wf *Workflow) ApplyEvent(event *fes.Event) error {
-	wfEvent, err := events.ParseWorkflow(event.Type)
+	eventData, err := unmarshalEventData(event)
 	if err != nil {
 		return err
 	}
-	switch wfEvent {
-	case events.Workflow_WORKFLOW_PARSING_FAILED:
-		wfErr := &types.Error{}
-		err := proto.Unmarshal(event.Data, wfErr)
-		if err != nil {
-			wfErr.Message = err.Error()
-			log.Errorf("failed to unmarshal event: '%v' (%v)", event, err)
-		}
 
-		wf.Status.Error = wfErr
+	switch m := eventData.(type) {
+	case *events.WorkflowParsingFailed:
+		wf.Status.Error = m.GetError()
 		wf.Status.UpdatedAt = event.GetTimestamp()
 		wf.Status.Status = types.WorkflowStatus_FAILED
-	case events.Workflow_WORKFLOW_CREATED:
-		spec := &types.WorkflowSpec{}
-		err := proto.Unmarshal(event.Data, spec)
-		if err != nil {
-			return err
-		}
-
+	case *events.WorkflowCreated:
 		// Setup object
 		wf.AggregatorMixin = fes.NewAggregatorMixin(wf, *event.Aggregate)
 		wf.Workflow = &types.Workflow{
@@ -65,23 +53,18 @@ func (wf *Workflow) ApplyEvent(event *fes.Event) error {
 				Id:        wf.Aggregate().Id,
 				CreatedAt: event.GetTimestamp(),
 			},
-			Spec: spec,
+			Spec: m.GetSpec(),
 			Status: &types.WorkflowStatus{
 				// TODO Nest into own state machine
 				Status:    types.WorkflowStatus_PENDING,
 				UpdatedAt: event.GetTimestamp(),
 			},
 		}
-	case events.Workflow_WORKFLOW_PARSED:
-		status := &types.WorkflowStatus{}
-		err := proto.Unmarshal(event.Data, status)
-		if err != nil {
-			return err
-		}
+	case *events.WorkflowParsed:
 		wf.Status.UpdatedAt = event.GetTimestamp()
 		wf.Status.Status = types.WorkflowStatus_READY
-		wf.Status.Tasks = status.Tasks
-	case events.Workflow_WORKFLOW_DELETED:
+		wf.Status.Tasks = m.GetTasks()
+	case *events.WorkflowDeleted:
 		wf.Status.Status = types.WorkflowStatus_DELETED
 	default:
 		log.WithFields(log.Fields{
diff --git a/pkg/types/events/events.pb.go b/pkg/types/events/events.pb.go
index 765f9f05..d56cd310 100644
--- a/pkg/types/events/events.pb.go
+++ b/pkg/types/events/events.pb.go
@@ -8,12 +8,27 @@ It is generated from these files:
 	pkg/types/events/events.proto
 
 It has these top-level messages:
+	EventWrapper
+	WorkflowCreated
+	WorkflowDeleted
+	WorkflowParsed
+	WorkflowParsingFailed
+	InvocationCreated
+	InvocationCompleted
+	InvocationCanceled
+	InvocationTaskAdded
+	InvocationFailed
+	TaskStarted
+	TaskSucceeded
+	TaskSkipped
+	TaskFailed
 */
 package events
 
 import proto "github.com/golang/protobuf/proto"
 import fmt "fmt"
 import math "math"
+import fission_workflows_types "github.com/fission/fission-workflows/pkg/types"
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -26,122 +41,267 @@ var _ = math.Inf
 // proto package needs to be updated.
 const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto package
 
-type Workflow int32
+type EventWrapper struct {
+	Any string `protobuf:"bytes,1,opt,name=any" json:"any,omitempty"`
+}
+
+func (m *EventWrapper) Reset()                    { *m = EventWrapper{} }
+func (m *EventWrapper) String() string            { return proto.CompactTextString(m) }
+func (*EventWrapper) ProtoMessage()               {}
+func (*EventWrapper) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
 
-const (
-	Workflow_WORKFLOW_CREATED        Workflow = 0
-	Workflow_WORKFLOW_UPDATED        Workflow = 1
-	Workflow_WORKFLOW_PARSED         Workflow = 2
-	Workflow_WORKFLOW_DELETED        Workflow = 3
-	Workflow_WORKFLOW_PARSING_FAILED Workflow = 4
-)
+func (m *EventWrapper) GetAny() string {
+	if m != nil {
+		return m.Any
+	}
+	return ""
+}
 
-var Workflow_name = map[int32]string{
-	0: "WORKFLOW_CREATED",
-	1: "WORKFLOW_UPDATED",
-	2: "WORKFLOW_PARSED",
-	3: "WORKFLOW_DELETED",
-	4: "WORKFLOW_PARSING_FAILED",
+type WorkflowCreated struct {
+	Spec *fission_workflows_types.WorkflowSpec `protobuf:"bytes,1,opt,name=spec" json:"spec,omitempty"`
 }
-var Workflow_value = map[string]int32{
-	"WORKFLOW_CREATED":        0,
-	"WORKFLOW_UPDATED":        1,
-	"WORKFLOW_PARSED":         2,
-	"WORKFLOW_DELETED":        3,
-	"WORKFLOW_PARSING_FAILED": 4,
+
+func (m *WorkflowCreated) Reset()                    { *m = WorkflowCreated{} }
+func (m *WorkflowCreated) String() string            { return proto.CompactTextString(m) }
+func (*WorkflowCreated) ProtoMessage()               {}
+func (*WorkflowCreated) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
+
+func (m *WorkflowCreated) GetSpec() *fission_workflows_types.WorkflowSpec {
+	if m != nil {
+		return m.Spec
+	}
+	return nil
 }
 
-func (x Workflow) String() string {
-	return proto.EnumName(Workflow_name, int32(x))
+type WorkflowDeleted struct {
 }
-func (Workflow) EnumDescriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
 
-type Invocation int32
+func (m *WorkflowDeleted) Reset()                    { *m = WorkflowDeleted{} }
+func (m *WorkflowDeleted) String() string            { return proto.CompactTextString(m) }
+func (*WorkflowDeleted) ProtoMessage()               {}
+func (*WorkflowDeleted) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{2} }
+
+type WorkflowParsed struct {
+	Tasks map[string]*fission_workflows_types.TaskStatus `protobuf:"bytes,1,rep,name=tasks" json:"tasks,omitempty" protobuf_key:"bytes,1,opt,name=key" protobuf_val:"bytes,2,opt,name=value"`
+}
 
-const (
-	Invocation_INVOCATION_CREATED    Invocation = 0
-	Invocation_INVOCATION_COMPLETED  Invocation = 1
-	Invocation_INVOCATION_CANCELED   Invocation = 2
-	Invocation_INVOCATION_TASK_ADDED Invocation = 3
-	Invocation_INVOCATION_FAILED     Invocation = 4
-)
+func (m *WorkflowParsed) Reset()                    { *m = WorkflowParsed{} }
+func (m *WorkflowParsed) String() string            { return proto.CompactTextString(m) }
+func (*WorkflowParsed) ProtoMessage()               {}
+func (*WorkflowParsed) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{3} }
 
-var Invocation_name = map[int32]string{
-	0: "INVOCATION_CREATED",
-	1: "INVOCATION_COMPLETED",
-	2: "INVOCATION_CANCELED",
-	3: "INVOCATION_TASK_ADDED",
-	4: "INVOCATION_FAILED",
+func (m *WorkflowParsed) GetTasks() map[string]*fission_workflows_types.TaskStatus {
+	if m != nil {
+		return m.Tasks
+	}
+	return nil
 }
-var Invocation_value = map[string]int32{
-	"INVOCATION_CREATED":    0,
-	"INVOCATION_COMPLETED":  1,
-	"INVOCATION_CANCELED":   2,
-	"INVOCATION_TASK_ADDED": 3,
-	"INVOCATION_FAILED":     4,
+
+type WorkflowParsingFailed struct {
+	Error *fission_workflows_types.Error `protobuf:"bytes,1,opt,name=error" json:"error,omitempty"`
 }
 
-func (x Invocation) String() string {
-	return proto.EnumName(Invocation_name, int32(x))
+func (m *WorkflowParsingFailed) Reset()                    { *m = WorkflowParsingFailed{} }
+func (m *WorkflowParsingFailed) String() string            { return proto.CompactTextString(m) }
+func (*WorkflowParsingFailed) ProtoMessage()               {}
+func (*WorkflowParsingFailed) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{4} }
+
+func (m *WorkflowParsingFailed) GetError() *fission_workflows_types.Error {
+	if m != nil {
+		return m.Error
+	}
+	return nil
 }
-func (Invocation) EnumDescriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
 
-type Task int32
+type InvocationCreated struct {
+	Spec *fission_workflows_types.WorkflowInvocationSpec `protobuf:"bytes,1,opt,name=spec" json:"spec,omitempty"`
+}
 
-const (
-	Task_TASK_STARTED   Task = 0
-	Task_TASK_SKIPPED   Task = 1
-	Task_TASK_SUCCEEDED Task = 4
-	Task_TASK_FAILED    Task = 5
-	Task_TASK_ABORTED   Task = 6
-)
+func (m *InvocationCreated) Reset()                    { *m = InvocationCreated{} }
+func (m *InvocationCreated) String() string            { return proto.CompactTextString(m) }
+func (*InvocationCreated) ProtoMessage()               {}
+func (*InvocationCreated) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{5} }
 
-var Task_name = map[int32]string{
-	0: "TASK_STARTED",
-	1: "TASK_SKIPPED",
-	4: "TASK_SUCCEEDED",
-	5: "TASK_FAILED",
-	6: "TASK_ABORTED",
+func (m *InvocationCreated) GetSpec() *fission_workflows_types.WorkflowInvocationSpec {
+	if m != nil {
+		return m.Spec
+	}
+	return nil
 }
-var Task_value = map[string]int32{
-	"TASK_STARTED":   0,
-	"TASK_SKIPPED":   1,
-	"TASK_SUCCEEDED": 4,
-	"TASK_FAILED":    5,
-	"TASK_ABORTED":   6,
+
+type InvocationCompleted struct {
+	Output *fission_workflows_types.TypedValue `protobuf:"bytes,1,opt,name=output" json:"output,omitempty"`
 }
 
-func (x Task) String() string {
-	return proto.EnumName(Task_name, int32(x))
+func (m *InvocationCompleted) Reset()                    { *m = InvocationCompleted{} }
+func (m *InvocationCompleted) String() string            { return proto.CompactTextString(m) }
+func (*InvocationCompleted) ProtoMessage()               {}
+func (*InvocationCompleted) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{6} }
+
+func (m *InvocationCompleted) GetOutput() *fission_workflows_types.TypedValue {
+	if m != nil {
+		return m.Output
+	}
+	return nil
+}
+
+type InvocationCanceled struct {
+	Error *fission_workflows_types.Error `protobuf:"bytes,1,opt,name=error" json:"error,omitempty"`
+}
+
+func (m *InvocationCanceled) Reset()                    { *m = InvocationCanceled{} }
+func (m *InvocationCanceled) String() string            { return proto.CompactTextString(m) }
+func (*InvocationCanceled) ProtoMessage()               {}
+func (*InvocationCanceled) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{7} }
+
+func (m *InvocationCanceled) GetError() *fission_workflows_types.Error {
+	if m != nil {
+		return m.Error
+	}
+	return nil
+}
+
+type InvocationTaskAdded struct {
+	Task *fission_workflows_types.Task `protobuf:"bytes,1,opt,name=task" json:"task,omitempty"`
+}
+
+func (m *InvocationTaskAdded) Reset()                    { *m = InvocationTaskAdded{} }
+func (m *InvocationTaskAdded) String() string            { return proto.CompactTextString(m) }
+func (*InvocationTaskAdded) ProtoMessage()               {}
+func (*InvocationTaskAdded) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{8} }
+
+func (m *InvocationTaskAdded) GetTask() *fission_workflows_types.Task {
+	if m != nil {
+		return m.Task
+	}
+	return nil
+}
+
+type InvocationFailed struct {
+	Error *fission_workflows_types.Error `protobuf:"bytes,1,opt,name=error" json:"error,omitempty"`
+}
+
+func (m *InvocationFailed) Reset()                    { *m = InvocationFailed{} }
+func (m *InvocationFailed) String() string            { return proto.CompactTextString(m) }
+func (*InvocationFailed) ProtoMessage()               {}
+func (*InvocationFailed) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{9} }
+
+func (m *InvocationFailed) GetError() *fission_workflows_types.Error {
+	if m != nil {
+		return m.Error
+	}
+	return nil
+}
+
+//
+// Task
+//
+// TODO why do we need task, and not just task spec.
+type TaskStarted struct {
+	Task *fission_workflows_types.TaskInvocation `protobuf:"bytes,1,opt,name=task" json:"task,omitempty"`
+}
+
+func (m *TaskStarted) Reset()                    { *m = TaskStarted{} }
+func (m *TaskStarted) String() string            { return proto.CompactTextString(m) }
+func (*TaskStarted) ProtoMessage()               {}
+func (*TaskStarted) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{10} }
+
+func (m *TaskStarted) GetTask() *fission_workflows_types.TaskInvocation {
+	if m != nil {
+		return m.Task
+	}
+	return nil
+}
+
+type TaskSucceeded struct {
+	Result *fission_workflows_types.TaskInvocationStatus `protobuf:"bytes,1,opt,name=result" json:"result,omitempty"`
+}
+
+func (m *TaskSucceeded) Reset()                    { *m = TaskSucceeded{} }
+func (m *TaskSucceeded) String() string            { return proto.CompactTextString(m) }
+func (*TaskSucceeded) ProtoMessage()               {}
+func (*TaskSucceeded) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{11} }
+
+func (m *TaskSucceeded) GetResult() *fission_workflows_types.TaskInvocationStatus {
+	if m != nil {
+		return m.Result
+	}
+	return nil
+}
+
+type TaskSkipped struct {
+}
+
+func (m *TaskSkipped) Reset()                    { *m = TaskSkipped{} }
+func (m *TaskSkipped) String() string            { return proto.CompactTextString(m) }
+func (*TaskSkipped) ProtoMessage()               {}
+func (*TaskSkipped) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{12} }
+
+type TaskFailed struct {
+	Error *fission_workflows_types.Error `protobuf:"bytes,1,opt,name=error" json:"error,omitempty"`
+}
+
+func (m *TaskFailed) Reset()                    { *m = TaskFailed{} }
+func (m *TaskFailed) String() string            { return proto.CompactTextString(m) }
+func (*TaskFailed) ProtoMessage()               {}
+func (*TaskFailed) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{13} }
+
+func (m *TaskFailed) GetError() *fission_workflows_types.Error {
+	if m != nil {
+		return m.Error
+	}
+	return nil
 }
-func (Task) EnumDescriptor() ([]byte, []int) { return fileDescriptor0, []int{2} }
 
 func init() {
-	proto.RegisterEnum("fission.workflows.events.Workflow", Workflow_name, Workflow_value)
-	proto.RegisterEnum("fission.workflows.events.Invocation", Invocation_name, Invocation_value)
-	proto.RegisterEnum("fission.workflows.events.Task", Task_name, Task_value)
+	proto.RegisterType((*EventWrapper)(nil), "fission.workflows.events.EventWrapper")
+	proto.RegisterType((*WorkflowCreated)(nil), "fission.workflows.events.WorkflowCreated")
+	proto.RegisterType((*WorkflowDeleted)(nil), "fission.workflows.events.WorkflowDeleted")
+	proto.RegisterType((*WorkflowParsed)(nil), "fission.workflows.events.WorkflowParsed")
+	proto.RegisterType((*WorkflowParsingFailed)(nil), "fission.workflows.events.WorkflowParsingFailed")
+	proto.RegisterType((*InvocationCreated)(nil), "fission.workflows.events.InvocationCreated")
+	proto.RegisterType((*InvocationCompleted)(nil), "fission.workflows.events.InvocationCompleted")
+	proto.RegisterType((*InvocationCanceled)(nil), "fission.workflows.events.InvocationCanceled")
+	proto.RegisterType((*InvocationTaskAdded)(nil), "fission.workflows.events.InvocationTaskAdded")
+	proto.RegisterType((*InvocationFailed)(nil), "fission.workflows.events.InvocationFailed")
+	proto.RegisterType((*TaskStarted)(nil), "fission.workflows.events.TaskStarted")
+	proto.RegisterType((*TaskSucceeded)(nil), "fission.workflows.events.TaskSucceeded")
+	proto.RegisterType((*TaskSkipped)(nil), "fission.workflows.events.TaskSkipped")
+	proto.RegisterType((*TaskFailed)(nil), "fission.workflows.events.TaskFailed")
 }
 
 func init() { proto.RegisterFile("pkg/types/events/events.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
-	// 287 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x54, 0x91, 0x41, 0x4f, 0x83, 0x30,
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+	// 471 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x94, 0x51, 0x6b, 0xd4, 0x40,
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+	0xf9, 0xd6, 0xe1, 0x34, 0x33, 0x3f, 0xab, 0xab, 0x30, 0x15, 0x37, 0x91, 0x2f, 0x6a, 0xd7, 0xdd,
+	0xbb, 0xe2, 0xa8, 0xa3, 0x37, 0x57, 0x47, 0xa5, 0x13, 0x78, 0x14, 0x5b, 0xca, 0xa5, 0x62, 0x52,
+	0xa2, 0x22, 0x1b, 0xb0, 0xca, 0xca, 0x7a, 0x1c, 0x4c, 0x82, 0x9d, 0x87, 0x89, 0xbd, 0xa5, 0x9f,
+	0xe0, 0xc9, 0xa5, 0x87, 0x1c, 0x2b, 0x64, 0x06, 0x39, 0x39, 0x80, 0x35, 0x2d, 0x31, 0x6d, 0xaa,
+	0x46, 0x7b, 0x2f, 0xc3, 0x3f, 0x95, 0xb9, 0x57, 0xb4, 0x7d, 0xe7, 0x12, 0xd3, 0xa4, 0x69, 0xa1,
+	0x9b, 0x1d, 0xed, 0x03, 0x16, 0x68, 0x90, 0xd3, 0x5f, 0x01, 0x3c, 0x6e, 0xf7, 0xbe, 0x30, 0xa5,
+	0x91, 0x93, 0x53, 0x18, 0x18, 0xa6, 0x73, 0x3d, 0x0e, 0x26, 0xab, 0x3b, 0xa3, 0xbd, 0xfd, 0x70,
+	0x9e, 0xf7, 0xf0, 0x7e, 0x63, 0xf8, 0xd5, 0x76, 0xc5, 0xa5, 0x51, 0x75, 0xe2, 0x08, 0x5b, 0x3f,
+	0x00, 0xba, 0x4d, 0x6b, 0x2f, 0xc7, 0x3b, 0x7b, 0x39, 0xd6, 0xe4, 0x00, 0x06, 0x33, 0x56, 0x54,
+	0x38, 0x5e, 0x69, 0xcc, 0xbc, 0x98, 0x6b, 0xc6, 0x52, 0xce, 0x0d, 0x33, 0x95, 0x4e, 0x5c, 0xc7,
+	0xe1, 0xca, 0xdb, 0x80, 0x7e, 0x86, 0x67, 0x7d, 0x09, 0x59, 0x39, 0xfd, 0xc8, 0xb2, 0x02, 0x39,
+	0x79, 0x03, 0x03, 0x54, 0x4a, 0x28, 0x1f, 0xd2, 0xf3, 0xb9, 0xdc, 0xd8, 0x56, 0x25, 0xae, 0x98,
+	0x7e, 0x83, 0xcd, 0xd3, 0x72, 0x26, 0x52, 0x66, 0x32, 0x51, 0xb6, 0x71, 0x1f, 0xdf, 0x8b, 0x3b,
+	0xfa, 0x6b, 0xdc, 0x1d, 0xa1, 0x17, 0x7c, 0x02, 0x4f, 0x7b, 0x64, 0x71, 0x23, 0x9b, 0xf0, 0xc9,
+	0x3b, 0x18, 0x8a, 0xca, 0xc8, 0xca, 0x78, 0xfa, 0x02, 0xff, 0xb5, 0x44, 0x7e, 0x61, 0x8d, 0x27,
+	0xbe, 0x85, 0x9e, 0x01, 0xe9, 0x31, 0x59, 0x99, 0xe2, 0xff, 0x3b, 0x3f, 0xe9, 0xeb, 0xb3, 0x59,
+	0xbf, 0xe7, 0x1c, 0x39, 0x79, 0x0d, 0x6b, 0x76, 0x8e, 0x9e, 0xb5, 0xbd, 0x70, 0x3a, 0x49, 0x53,
+	0x4a, 0x4f, 0x60, 0xa3, 0x23, 0x2d, 0x35, 0x8d, 0x33, 0x18, 0xf9, 0xa9, 0x2b, 0x97, 0x55, 0x5f,
+	0xcb, 0xab, 0x85, 0x5a, 0x3a, 0x05, 0x5e, 0xd5, 0x05, 0xac, 0x37, 0xac, 0x2a, 0x4d, 0x11, 0xad,
+	0xb3, 0x18, 0x86, 0x0a, 0x75, 0x55, 0xb4, 0xc9, 0xef, 0xfe, 0x23, 0xcf, 0x9f, 0x41, 0xdf, 0x4c,
+	0xd7, 0xbd, 0xc6, 0x3c, 0x93, 0x12, 0x39, 0x3d, 0x72, 0xc7, 0x7d, 0x19, 0xdb, 0x47, 0x0f, 0xbe,
+	0x0f, 0xdd, 0xd7, 0x75, 0x35, 0x6c, 0x7e, 0x12, 0xfb, 0xbf, 0x03, 0x00, 0x00, 0xff, 0xff, 0x37,
+	0x39, 0x48, 0x43, 0x9b, 0x04, 0x00, 0x00,
 }
diff --git a/pkg/types/events/events.proto b/pkg/types/events/events.proto
index 75a3ff62..2c5ae420 100644
--- a/pkg/types/events/events.proto
+++ b/pkg/types/events/events.proto
@@ -3,26 +3,70 @@ syntax = "proto3";
 package fission.workflows.events;
 option go_package = "events";
 
-enum Workflow {
-    WORKFLOW_CREATED = 0;
-    WORKFLOW_UPDATED = 1;
-    WORKFLOW_PARSED = 2;
-    WORKFLOW_DELETED = 3;
-    WORKFLOW_PARSING_FAILED = 4;
+import "github.com/fission/fission-workflows/pkg/types/types.proto";
+
+message EventWrapper {
+    string any = 1;
+}
+
+//
+// Workflow
+//
+
+message WorkflowCreated {
+    fission.workflows.types.WorkflowSpec spec = 1;
+}
+
+message WorkflowDeleted {
+}
+
+message WorkflowParsed {
+    map<string, fission.workflows.types.TaskStatus> tasks = 1;
+}
+
+message WorkflowParsingFailed {
+    fission.workflows.types.Error error = 1;
+}
+
+//
+// Invocation
+//
+
+message InvocationCreated {
+    fission.workflows.types.WorkflowInvocationSpec spec = 1;
+}
+
+message InvocationCompleted {
+    fission.workflows.types.TypedValue output = 1;
+}
+
+message InvocationCanceled {
+    fission.workflows.types.Error error = 1;
+}
+
+message InvocationTaskAdded {
+    fission.workflows.types.Task task = 1;
+}
+
+message InvocationFailed {
+    fission.workflows.types.Error error = 1;
 }
 
-enum Invocation {
-    INVOCATION_CREATED = 0; // origin: User
-    INVOCATION_COMPLETED = 1; // origin: Engine
-    INVOCATION_CANCELED = 2; // origin: User
-    INVOCATION_TASK_ADDED = 3;
-    INVOCATION_FAILED = 4;
+//
+// Task
+//
+// TODO why do we need task, and not just task spec.
+message TaskStarted {
+    fission.workflows.types.TaskInvocation task = 1;
 }
 
-enum Task {
-    TASK_STARTED = 0; // origin: Engine
-    TASK_SKIPPED = 1; // origin: Engine
-    TASK_SUCCEEDED = 4; // origin: Task
-    TASK_FAILED = 5; // origin: Task
-    TASK_ABORTED = 6; // origin: Engine
+message TaskSucceeded {
+    fission.workflows.types.TaskInvocationStatus result = 1;
 }
+
+message TaskSkipped {
+}
+
+message TaskFailed {
+    fission.workflows.types.Error error = 1;
+}
\ No newline at end of file
diff --git a/pkg/types/events/fsm.go b/pkg/types/events/fsm.go
deleted file mode 100644
index 95b45c97..00000000
--- a/pkg/types/events/fsm.go
+++ /dev/null
@@ -1,32 +0,0 @@
-package events
-
-import (
-	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/util/fsm"
-)
-
-var WorkflowInvocationFsm = fsm.New(
-	types.WorkflowInvocationStatus_UNKNOWN,
-	[]fsm.Transition{
-		{
-			Event: Invocation_INVOCATION_CREATED,
-			Src:   types.WorkflowInvocationStatus_UNKNOWN,
-			Dst:   types.WorkflowInvocationStatus_SCHEDULED,
-		},
-		{
-			Event: Invocation_INVOCATION_CANCELED,
-			Src:   types.WorkflowInvocationStatus_SCHEDULED,
-			Dst:   types.WorkflowInvocationStatus_ABORTED,
-		},
-		{
-			Event: Invocation_INVOCATION_CANCELED,
-			Src:   types.WorkflowInvocationStatus_IN_PROGRESS,
-			Dst:   types.WorkflowInvocationStatus_ABORTED,
-		},
-		{
-			Event: Invocation_INVOCATION_COMPLETED,
-			Src:   types.WorkflowInvocationStatus_IN_PROGRESS,
-			Dst:   types.WorkflowInvocationStatus_SUCCEEDED,
-		},
-	},
-)
diff --git a/pkg/types/events/util.go b/pkg/types/events/util.go
deleted file mode 100644
index 324eab47..00000000
--- a/pkg/types/events/util.go
+++ /dev/null
@@ -1,34 +0,0 @@
-package events
-
-import (
-	"errors"
-)
-
-var (
-	ErrUnknownEvent = errors.New("unknown event")
-)
-
-// ResolveTask attempts to convert a string-based flag to the appropriate InvocationEvent.
-func ParseInvocation(event string) (Invocation, error) {
-	val, ok := Invocation_value[event]
-	if !ok {
-		return -1, ErrUnknownEvent
-	}
-	return Invocation(val), nil
-}
-
-func ParseWorkflow(flag string) (Workflow, error) {
-	val, ok := Workflow_value[flag]
-	if !ok {
-		return -1, ErrUnknownEvent
-	}
-	return Workflow(val), nil
-}
-
-func ParseTask(event string) (Task, error) {
-	val, ok := Task_value[event]
-	if !ok {
-		return -1, ErrUnknownEvent
-	}
-	return Task(val), nil
-}

From 2b8c283bf8dacc6ed1f4d2e2f46425bc79a5c4bf Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Tue, 17 Jul 2018 15:54:45 +0200
Subject: [PATCH 03/10] Remove verbose projection code in favor of simple
 approach

---
 pkg/fes/backend/mem/mem.go   |  2 +-
 pkg/fes/backend/nats/nats.go |  2 +-
 pkg/fes/projectors.go        | 34 ----------------------------------
 pkg/fes/proto.go             |  2 --
 pkg/fes/types.go             |  6 ++----
 pkg/fes/util.go              | 34 +++++++++++++++++++++++++++-------
 6 files changed, 31 insertions(+), 49 deletions(-)
 delete mode 100644 pkg/fes/projectors.go

diff --git a/pkg/fes/backend/mem/mem.go b/pkg/fes/backend/mem/mem.go
index a296a72a..7941f244 100644
--- a/pkg/fes/backend/mem/mem.go
+++ b/pkg/fes/backend/mem/mem.go
@@ -74,7 +74,7 @@ func (b *Backend) List(matcher fes.StringMatcher) ([]fes.Aggregate, error) {
 	var results []fes.Aggregate
 	for k := range b.contents {
 		// TODO change matcher to fes.AggregateMatcher instead
-		if matcher.Match(k.Type + k.Id) {
+		if matcher(k.Type + k.Id) {
 			results = append(results, k)
 		}
 	}
diff --git a/pkg/fes/backend/nats/nats.go b/pkg/fes/backend/nats/nats.go
index f8554938..575c2893 100644
--- a/pkg/fes/backend/nats/nats.go
+++ b/pkg/fes/backend/nats/nats.go
@@ -266,7 +266,7 @@ func (wc *WildcardConn) List(matcher fes.StringMatcher) ([]string, error) {
 		}
 
 		subject := subjectEvent.Subject
-		if matcher.Match(subject) {
+		if matcher(subject) {
 			count := 1
 			if c, ok := subjectCount[subject]; ok {
 				count += c
diff --git a/pkg/fes/projectors.go b/pkg/fes/projectors.go
deleted file mode 100644
index 44f479c8..00000000
--- a/pkg/fes/projectors.go
+++ /dev/null
@@ -1,34 +0,0 @@
-package fes
-
-import "github.com/sirupsen/logrus"
-
-var DefaultProjector = SimpleProjector{}
-
-func Project(target Aggregator, events ...*Event) error {
-	return DefaultProjector.Project(target, events...)
-}
-
-type SimpleProjector struct{}
-
-func (rp *SimpleProjector) Project(target Aggregator, events ...*Event) error {
-	for _, event := range events {
-		err := rp.project(target, event)
-		if err != nil {
-			return err
-		}
-	}
-
-	return nil
-}
-
-func (rp *SimpleProjector) project(target Aggregator, event *Event) error {
-	if event == nil {
-		logrus.WithField("target", target).Warn("Empty event received")
-		return nil
-	}
-	if target == nil {
-		logrus.WithField("target", target).Warn("Empty target")
-		return nil
-	}
-	return target.ApplyEvent(event)
-}
diff --git a/pkg/fes/proto.go b/pkg/fes/proto.go
index 3cc4612d..a3a1e1a3 100644
--- a/pkg/fes/proto.go
+++ b/pkg/fes/proto.go
@@ -24,8 +24,6 @@ func (m *Event) Labels() labels.Labels {
 		parent = &Aggregate{}
 	}
 
-	// TODO could be created using reflection
-	// TODO cache somewhere to avoid rebuilding on every request
 	return labels.Set{
 		"aggregate.id":   m.Aggregate.Id,
 		"aggregate.type": m.Aggregate.Type,
diff --git a/pkg/fes/types.go b/pkg/fes/types.go
index 27edd4f1..3b28fb6a 100644
--- a/pkg/fes/types.go
+++ b/pkg/fes/types.go
@@ -5,8 +5,8 @@ import "github.com/fission/fission-workflows/pkg/util/pubsub"
 // Aggregator is a entity that can be updated
 // TODO we need to keep more event-related information (such as current index)
 type Aggregator interface {
+
 	// Entity-specific
-	// TODO can we avoid mutability here?
 	ApplyEvent(event *Event) error
 
 	// Aggregate provides type information about the entity, such as the aggregate id and the aggregate type.
@@ -57,9 +57,7 @@ type CacheReaderWriter interface {
 	CacheWriter
 }
 
-type StringMatcher interface {
-	Match(target string) bool
-}
+type StringMatcher func(target string) bool
 
 type Notification struct {
 	*pubsub.EmptyMsg
diff --git a/pkg/fes/util.go b/pkg/fes/util.go
index 89bcd07e..2ff8a284 100644
--- a/pkg/fes/util.go
+++ b/pkg/fes/util.go
@@ -9,17 +9,25 @@ import (
 	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
 	"github.com/golang/protobuf/ptypes/any"
+	log "github.com/sirupsen/logrus"
 )
 
-func validateAggregate(aggregate Aggregate) error {
-	if len(aggregate.Id) == 0 {
-		return errors.New("aggregate does not contain id")
+// Project is convenience function to apply events to an entity.
+func Project(entity Aggregator, events ...*Event) error {
+	if entity == nil {
+		log.WithField("entity", entity).Warn("Empty entity")
+		return nil
 	}
-
-	if len(aggregate.Type) == 0 {
-		return errors.New("aggregate does not contain type")
+	for _, event := range events {
+		if event == nil {
+			log.WithField("entity", entity).Warn("Empty event received")
+			return nil
+		}
+		err := entity.ApplyEvent(event)
+		if err != nil {
+			return err
+		}
 	}
-
 	return nil
 }
 
@@ -68,3 +76,15 @@ func NewEvent(aggregate Aggregate, msg proto.Message) (*Event, error) {
 		Type:      reflect.Indirect(reflect.ValueOf(msg)).Type().Name(),
 	}, nil
 }
+
+func validateAggregate(aggregate Aggregate) error {
+	if len(aggregate.Id) == 0 {
+		return errors.New("aggregate does not contain id")
+	}
+
+	if len(aggregate.Type) == 0 {
+		return errors.New("aggregate does not contain type")
+	}
+
+	return nil
+}

From 5a116ef58e831930db1be18f044c281bbb4bc1b2 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Tue, 17 Jul 2018 15:59:15 +0200
Subject: [PATCH 04/10] Renamed fes.Aggregator -> fes.Entity

---
 cmd/fission-workflows-bundle/bundle/bundle.go |  4 +--
 pkg/fes/backend/mem/mem.go                    |  5 ++--
 pkg/fes/backend/nats/client.go                |  4 +--
 pkg/fes/caches.go                             | 26 +++++++++----------
 pkg/fes/{aggregator.go => entity.go}          | 20 +++++++-------
 .../{aggregator_test.go => entity_test.go}    |  8 +++---
 pkg/fes/proto.go                              |  2 +-
 pkg/fes/types.go                              | 24 ++++++++---------
 pkg/fes/util.go                               |  2 +-
 pkg/types/aggregates/invocation.go            | 10 +++----
 pkg/types/aggregates/task.go                  |  8 +++---
 pkg/types/aggregates/workflow.go              | 10 +++----
 12 files changed, 61 insertions(+), 62 deletions(-)
 rename pkg/fes/{aggregator.go => entity.go} (65%)
 rename pkg/fes/{aggregator_test.go => entity_test.go} (74%)

diff --git a/cmd/fission-workflows-bundle/bundle/bundle.go b/cmd/fission-workflows-bundle/bundle/bundle.go
index 048963a6..d7f684c2 100644
--- a/cmd/fission-workflows-bundle/bundle/bundle.go
+++ b/cmd/fission-workflows-bundle/bundle/bundle.go
@@ -346,7 +346,7 @@ func setupWorkflowInvocationCache(ctx context.Context, invocationEventPub pubsub
 			labels.In(fes.PubSubLabelAggregateType, "invocation"),
 			labels.In("parent.type", "invocation")),
 	})
-	wi := func() fes.Aggregator {
+	wi := func() fes.Entity {
 		return aggregates.NewWorkflowInvocation("")
 	}
 
@@ -358,7 +358,7 @@ func setupWorkflowCache(ctx context.Context, workflowEventPub pubsub.Publisher)
 		Buffer:       10,
 		LabelMatcher: labels.In(fes.PubSubLabelAggregateType, "workflow"),
 	})
-	wb := func() fes.Aggregator {
+	wb := func() fes.Entity {
 		return aggregates.NewWorkflow("")
 	}
 	return fes.NewSubscribedCache(ctx, fes.NewNamedMapCache("workflow"), wb, wfSub)
diff --git a/pkg/fes/backend/mem/mem.go b/pkg/fes/backend/mem/mem.go
index 7941f244..73afa719 100644
--- a/pkg/fes/backend/mem/mem.go
+++ b/pkg/fes/backend/mem/mem.go
@@ -67,14 +67,13 @@ func (b *Backend) Get(key fes.Aggregate) ([]*fes.Event, error) {
 	return events, nil
 }
 
-func (b *Backend) List(matcher fes.StringMatcher) ([]fes.Aggregate, error) {
+func (b *Backend) List(matchFn fes.StringMatcher) ([]fes.Aggregate, error) {
 	b.lock.RLock()
 	defer b.lock.RUnlock()
 
 	var results []fes.Aggregate
 	for k := range b.contents {
-		// TODO change matcher to fes.AggregateMatcher instead
-		if matcher(k.Type + k.Id) {
+		if matchFn(k.Type + k.Id) {
 			results = append(results, k)
 		}
 	}
diff --git a/pkg/fes/backend/nats/client.go b/pkg/fes/backend/nats/client.go
index cdf94427..cf0768e2 100644
--- a/pkg/fes/backend/nats/client.go
+++ b/pkg/fes/backend/nats/client.go
@@ -193,8 +193,8 @@ func (es *EventStore) Get(aggregate fes.Aggregate) ([]*fes.Event, error) {
 }
 
 // List returns all entities of which the subject matches the StringMatcher
-func (es *EventStore) List(matcher fes.StringMatcher) ([]fes.Aggregate, error) {
-	subjects, err := es.conn.List(matcher)
+func (es *EventStore) List(matchFn fes.StringMatcher) ([]fes.Aggregate, error) {
+	subjects, err := es.conn.List(matchFn)
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/fes/caches.go b/pkg/fes/caches.go
index 53ff7007..10cdc3e3 100644
--- a/pkg/fes/caches.go
+++ b/pkg/fes/caches.go
@@ -39,13 +39,13 @@ func init() {
 // MapCache provides a simple non-preempting map-based CacheReaderWriter implementation.
 type MapCache struct {
 	Name     string
-	contents map[string]map[string]Aggregator // Map: AggregateType -> AggregateId -> entity
+	contents map[string]map[string]Entity // Map: AggregateType -> AggregateId -> entity
 	lock     *sync.RWMutex
 }
 
 func NewMapCache() *MapCache {
 	c := &MapCache{
-		contents: map[string]map[string]Aggregator{},
+		contents: map[string]map[string]Entity{},
 		lock:     &sync.RWMutex{},
 	}
 	c.Name = fmt.Sprintf("%p", c)
@@ -54,13 +54,13 @@ func NewMapCache() *MapCache {
 
 func NewNamedMapCache(name string) *MapCache {
 	return &MapCache{
-		contents: map[string]map[string]Aggregator{},
+		contents: map[string]map[string]Entity{},
 		lock:     &sync.RWMutex{},
 		Name:     name,
 	}
 }
 
-func (rc *MapCache) Get(entity Aggregator) error {
+func (rc *MapCache) Get(entity Entity) error {
 	if entity == nil {
 		return errors.New("entity is nil")
 	}
@@ -85,7 +85,7 @@ func (rc *MapCache) Get(entity Aggregator) error {
 	return e
 }
 
-func (rc *MapCache) GetAggregate(aggregate Aggregate) (Aggregator, error) {
+func (rc *MapCache) GetAggregate(aggregate Aggregate) (Entity, error) {
 	err := validateAggregate(aggregate)
 	if err != nil {
 		return nil, err
@@ -106,7 +106,7 @@ func (rc *MapCache) GetAggregate(aggregate Aggregate) (Aggregator, error) {
 	return cached, nil
 }
 
-func (rc *MapCache) Put(entity Aggregator) error {
+func (rc *MapCache) Put(entity Entity) error {
 	ref := entity.Aggregate()
 	err := validateAggregate(ref)
 	if err != nil {
@@ -116,7 +116,7 @@ func (rc *MapCache) Put(entity Aggregator) error {
 	rc.lock.Lock()
 	defer rc.lock.Unlock()
 	if _, ok := rc.contents[ref.Type]; !ok {
-		rc.contents[ref.Type] = map[string]Aggregator{}
+		rc.contents[ref.Type] = map[string]Entity{}
 	}
 	rc.contents[ref.Type][ref.Id] = entity
 	cacheCount.WithLabelValues(rc.Name).Inc()
@@ -147,10 +147,10 @@ type SubscribedCache struct {
 	pubsub.Publisher
 	CacheReaderWriter
 	ts     time.Time
-	target func() Aggregator // TODO extract to a TypedSubscription
+	target func() Entity // TODO extract to a TypedSubscription
 }
 
-func NewSubscribedCache(ctx context.Context, cache CacheReaderWriter, target func() Aggregator, sub *pubsub.Subscription) *SubscribedCache {
+func NewSubscribedCache(ctx context.Context, cache CacheReaderWriter, target func() Entity, sub *pubsub.Subscription) *SubscribedCache {
 	c := &SubscribedCache{
 		Publisher:         pubsub.NewPublisher(),
 		CacheReaderWriter: cache,
@@ -246,7 +246,7 @@ type FallbackCache struct {
 	cache  CacheReaderWriter
 	client Backend
 	domain StringMatcher
-	target func() Aggregator // TODO extract to a TypedSubscription
+	target func() Entity // TODO extract to a TypedSubscription
 }
 
 func (c *FallbackCache) List() []Aggregate {
@@ -280,7 +280,7 @@ func (c *FallbackCache) List() []Aggregate {
 	return esAggregates
 }
 
-func (c *FallbackCache) GetAggregate(a Aggregate) (Aggregator, error) {
+func (c *FallbackCache) GetAggregate(a Aggregate) (Entity, error) {
 	cached, err := c.cache.GetAggregate(a)
 	if err != nil {
 		if err == ErrNotFound {
@@ -296,7 +296,7 @@ func (c *FallbackCache) GetAggregate(a Aggregate) (Aggregator, error) {
 	return cached, nil
 }
 
-func (c *FallbackCache) Get(entity Aggregator) error {
+func (c *FallbackCache) Get(entity Entity) error {
 	err := c.cache.Get(entity)
 	if err != nil {
 		if err == ErrNotFound {
@@ -307,7 +307,7 @@ func (c *FallbackCache) Get(entity Aggregator) error {
 	return nil
 }
 
-func (c *FallbackCache) getFromEventStore(aggregate Aggregate, target Aggregator) error {
+func (c *FallbackCache) getFromEventStore(aggregate Aggregate, target Entity) error {
 	// Look up relevant events in event store
 	events, err := c.client.Get(aggregate)
 	if err != nil {
diff --git a/pkg/fes/aggregator.go b/pkg/fes/entity.go
similarity index 65%
rename from pkg/fes/aggregator.go
rename to pkg/fes/entity.go
index 208e5579..6e5ec480 100644
--- a/pkg/fes/aggregator.go
+++ b/pkg/fes/entity.go
@@ -5,27 +5,27 @@ import (
 	"reflect"
 )
 
-// AggregatorMixin is a helper to implement most of the Aggregator interface.
+// BaseEntity is a helper to implement most of the Entity interface.
 //
 // Structs using this struct will only need to implement the following methods:
 // - ApplyEvent(event)
-type AggregatorMixin struct {
+type BaseEntity struct {
 	aggregate Aggregate
 	// parent is a pointer to the wrapper of this mixin, to allow for reflection-based aggregation.
-	parent Aggregator
+	parent Entity
 
 	version uint
 }
 
-func (am *AggregatorMixin) Aggregate() Aggregate {
+func (am *BaseEntity) Aggregate() Aggregate {
 	return am.aggregate
 }
 
-// UpdateState mutates the current Aggregator to the new provided Aggregator.
+// UpdateState mutates the current Entity to the new provided Entity.
 //
 // By default it uses reflection to update the fields. For improved performance override this method with a
 // aggregate-specific one.
-func (am *AggregatorMixin) UpdateState(newState Aggregator) error {
+func (am *BaseEntity) UpdateState(newState Entity) error {
 	if newState.Aggregate() != am.Aggregate() {
 		return errors.New("invalid newState")
 	}
@@ -46,15 +46,15 @@ func (am *AggregatorMixin) UpdateState(newState Aggregator) error {
 	return nil
 }
 
-func (am AggregatorMixin) CopyAggregatorMixin(self Aggregator) *AggregatorMixin {
-	return &AggregatorMixin{
+func (am BaseEntity) CopyBaseEntity(self Entity) *BaseEntity {
+	return &BaseEntity{
 		aggregate: am.aggregate,
 		parent:    self,
 	}
 }
 
-func NewAggregatorMixin(thiz Aggregator, aggregate Aggregate) *AggregatorMixin {
-	return &AggregatorMixin{
+func NewBaseEntity(thiz Entity, aggregate Aggregate) *BaseEntity {
+	return &BaseEntity{
 		aggregate: aggregate,
 		parent:    thiz,
 	}
diff --git a/pkg/fes/aggregator_test.go b/pkg/fes/entity_test.go
similarity index 74%
rename from pkg/fes/aggregator_test.go
rename to pkg/fes/entity_test.go
index 7953bb60..9c02c174 100644
--- a/pkg/fes/aggregator_test.go
+++ b/pkg/fes/entity_test.go
@@ -7,7 +7,7 @@ import (
 )
 
 type MockAggregate struct {
-	*AggregatorMixin
+	*BaseEntity
 	Val int
 }
 
@@ -15,11 +15,11 @@ func newMockAggregate(id string, atype string, val int) *MockAggregate {
 	m := &MockAggregate{
 		Val: val,
 	}
-	m.AggregatorMixin = NewAggregatorMixin(m, Aggregate{id, atype})
+	m.BaseEntity = NewBaseEntity(m, Aggregate{id, atype})
 	return m
 }
 
-func (ma *MockAggregate) GenericCopy() Aggregator {
+func (ma *MockAggregate) GenericCopy() Entity {
 	panic("implement me")
 }
 
@@ -27,7 +27,7 @@ func (ma *MockAggregate) ApplyEvent(event *Event) error {
 	panic("Should not be relevant")
 }
 
-func TestNewAggregatorMixin(t *testing.T) {
+func TestNewBaseEntity(t *testing.T) {
 	src := newMockAggregate("1", "foo", 1)
 	updated := newMockAggregate("1", "foo", 2)
 
diff --git a/pkg/fes/proto.go b/pkg/fes/proto.go
index a3a1e1a3..e73805b6 100644
--- a/pkg/fes/proto.go
+++ b/pkg/fes/proto.go
@@ -34,7 +34,7 @@ func (m *Event) Labels() labels.Labels {
 	}
 }
 
-func (m *Event) BelongsTo(parent Aggregator) bool {
+func (m *Event) BelongsTo(parent Entity) bool {
 	a := parent.Aggregate()
 	return *m.Aggregate != a && *m.Parent != a
 }
diff --git a/pkg/fes/types.go b/pkg/fes/types.go
index 3b28fb6a..93504472 100644
--- a/pkg/fes/types.go
+++ b/pkg/fes/types.go
@@ -2,25 +2,25 @@ package fes
 
 import "github.com/fission/fission-workflows/pkg/util/pubsub"
 
-// Aggregator is a entity that can be updated
+// Entity is a entity that can be updated
 // TODO we need to keep more event-related information (such as current index)
-type Aggregator interface {
+type Entity interface {
 
 	// Entity-specific
 	ApplyEvent(event *Event) error
 
 	// Aggregate provides type information about the entity, such as the aggregate id and the aggregate type.
 	//
-	// This is implemented by AggregatorMixin
+	// This is implemented by BaseEntity
 	Aggregate() Aggregate
 
 	// UpdateState mutates the current entity to the provided target state
 	//
-	// This is implemented by AggregatorMixin, can be overridden for performance approach
-	UpdateState(targetState Aggregator) error
+	// This is implemented by BaseEntity, can be overridden for performance approach
+	UpdateState(targetState Entity) error
 
 	// Copy copies the actual wrapped object. This is useful to get a snapshot of the state.
-	GenericCopy() Aggregator
+	GenericCopy() Entity
 }
 
 type EventAppender interface {
@@ -38,17 +38,17 @@ type Backend interface {
 
 // Projector projects events into an entity
 type Projector interface {
-	Project(target Aggregator, events ...*Event) error
+	Project(target Entity, events ...*Event) error
 }
 
 type CacheReader interface {
-	Get(entity Aggregator) error
+	Get(entity Entity) error
 	List() []Aggregate
-	GetAggregate(a Aggregate) (Aggregator, error)
+	GetAggregate(a Aggregate) (Entity, error)
 }
 
 type CacheWriter interface {
-	Put(entity Aggregator) error
+	Put(entity Entity) error
 	Invalidate(entity *Aggregate)
 }
 
@@ -61,11 +61,11 @@ type StringMatcher func(target string) bool
 
 type Notification struct {
 	*pubsub.EmptyMsg
-	Payload   Aggregator
+	Payload   Entity
 	EventType string
 }
 
-func newNotification(entity Aggregator, event *Event) *Notification {
+func newNotification(entity Entity, event *Event) *Notification {
 	return &Notification{
 		EmptyMsg:  pubsub.NewEmptyMsg(event.Labels(), event.CreatedAt()),
 		Payload:   entity,
diff --git a/pkg/fes/util.go b/pkg/fes/util.go
index 2ff8a284..b0f1ca42 100644
--- a/pkg/fes/util.go
+++ b/pkg/fes/util.go
@@ -13,7 +13,7 @@ import (
 )
 
 // Project is convenience function to apply events to an entity.
-func Project(entity Aggregator, events ...*Event) error {
+func Project(entity Entity, events ...*Event) error {
 	if entity == nil {
 		log.WithField("entity", entity).Warn("Empty entity")
 		return nil
diff --git a/pkg/types/aggregates/invocation.go b/pkg/types/aggregates/invocation.go
index 21eed9d3..40802b66 100644
--- a/pkg/types/aggregates/invocation.go
+++ b/pkg/types/aggregates/invocation.go
@@ -15,7 +15,7 @@ const (
 )
 
 type WorkflowInvocation struct {
-	*fes.AggregatorMixin
+	*fes.BaseEntity
 	*types.WorkflowInvocation
 }
 
@@ -25,7 +25,7 @@ func NewWorkflowInvocation(invocationID string, wi ...*types.WorkflowInvocation)
 		wia.WorkflowInvocation = wi[0]
 	}
 
-	wia.AggregatorMixin = fes.NewAggregatorMixin(wia, *NewWorkflowInvocationAggregate(invocationID))
+	wia.BaseEntity = fes.NewBaseEntity(wia, *NewWorkflowInvocationAggregate(invocationID))
 	return wia
 }
 
@@ -49,7 +49,7 @@ func (wi *WorkflowInvocation) ApplyEvent(event *fes.Event) error {
 
 	switch m := eventData.(type) {
 	case *events.InvocationCreated:
-		wi.AggregatorMixin = fes.NewAggregatorMixin(wi, *event.Aggregate)
+		wi.BaseEntity = fes.NewBaseEntity(wi, *event.Aggregate)
 		wi.WorkflowInvocation = &types.WorkflowInvocation{
 			Metadata: &types.ObjectMetadata{
 				Id:        event.Aggregate.Id,
@@ -120,11 +120,11 @@ func (wi *WorkflowInvocation) applyTaskEvent(event *fes.Event) error {
 	return nil
 }
 
-func (wi *WorkflowInvocation) GenericCopy() fes.Aggregator {
+func (wi *WorkflowInvocation) GenericCopy() fes.Entity {
 	n := &WorkflowInvocation{
 		WorkflowInvocation: wi.Copy(),
 	}
-	n.AggregatorMixin = wi.CopyAggregatorMixin(n)
+	n.BaseEntity = wi.CopyBaseEntity(n)
 	return n
 }
 
diff --git a/pkg/types/aggregates/task.go b/pkg/types/aggregates/task.go
index 559b22db..b06535e9 100644
--- a/pkg/types/aggregates/task.go
+++ b/pkg/types/aggregates/task.go
@@ -13,7 +13,7 @@ const (
 )
 
 type TaskInvocation struct {
-	*fes.AggregatorMixin
+	*fes.BaseEntity
 	*types.TaskInvocation
 }
 
@@ -22,7 +22,7 @@ func NewTaskInvocation(id string, fi *types.TaskInvocation) *TaskInvocation {
 		TaskInvocation: fi,
 	}
 
-	tia.AggregatorMixin = fes.NewAggregatorMixin(tia, *NewTaskInvocationAggregate(id))
+	tia.BaseEntity = fes.NewBaseEntity(tia, *NewTaskInvocationAggregate(id))
 
 	return tia
 }
@@ -75,11 +75,11 @@ func (ti *TaskInvocation) ApplyEvent(event *fes.Event) error {
 	return nil
 }
 
-func (ti *TaskInvocation) GenericCopy() fes.Aggregator {
+func (ti *TaskInvocation) GenericCopy() fes.Entity {
 	n := &TaskInvocation{
 		TaskInvocation: ti.Copy(),
 	}
-	n.AggregatorMixin = ti.CopyAggregatorMixin(n)
+	n.BaseEntity = ti.CopyBaseEntity(n)
 	return n
 }
 
diff --git a/pkg/types/aggregates/workflow.go b/pkg/types/aggregates/workflow.go
index 2ef7f711..0641f088 100644
--- a/pkg/types/aggregates/workflow.go
+++ b/pkg/types/aggregates/workflow.go
@@ -13,7 +13,7 @@ const (
 )
 
 type Workflow struct {
-	*fes.AggregatorMixin
+	*fes.BaseEntity
 	*types.Workflow
 }
 
@@ -23,7 +23,7 @@ func NewWorkflow(workflowID string, wi ...*types.Workflow) *Workflow {
 		wia.Workflow = wi[0]
 	}
 
-	wia.AggregatorMixin = fes.NewAggregatorMixin(wia, *NewWorkflowAggregate(workflowID))
+	wia.BaseEntity = fes.NewBaseEntity(wia, *NewWorkflowAggregate(workflowID))
 	return wia
 }
 
@@ -47,7 +47,7 @@ func (wf *Workflow) ApplyEvent(event *fes.Event) error {
 		wf.Status.Status = types.WorkflowStatus_FAILED
 	case *events.WorkflowCreated:
 		// Setup object
-		wf.AggregatorMixin = fes.NewAggregatorMixin(wf, *event.Aggregate)
+		wf.BaseEntity = fes.NewBaseEntity(wf, *event.Aggregate)
 		wf.Workflow = &types.Workflow{
 			Metadata: &types.ObjectMetadata{
 				Id:        wf.Aggregate().Id,
@@ -74,11 +74,11 @@ func (wf *Workflow) ApplyEvent(event *fes.Event) error {
 	return nil
 }
 
-func (wf *Workflow) GenericCopy() fes.Aggregator {
+func (wf *Workflow) GenericCopy() fes.Entity {
 	n := &Workflow{
 		Workflow: wf.Copy(),
 	}
-	n.AggregatorMixin = wf.CopyAggregatorMixin(n)
+	n.BaseEntity = wf.CopyBaseEntity(n)
 	return n
 }
 

From 6381826954aeb677bcbb8f66ba917d9a7f37b8f9 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Tue, 17 Jul 2018 16:29:01 +0200
Subject: [PATCH 05/10] Move event data unmarshalling utility function to fes

---
 pkg/api/task.go                    |  2 +-
 pkg/fes/fes.pb.go                  | 59 +++++++++++++++++---------
 pkg/fes/fes.proto                  |  4 ++
 pkg/fes/util.go                    | 33 +++++++++------
 pkg/types/aggregates/aggregates.go | 15 -------
 pkg/types/aggregates/invocation.go |  2 +-
 pkg/types/aggregates/task.go       |  7 ++-
 pkg/types/aggregates/workflow.go   |  2 +-
 pkg/types/events/events.pb.go      | 68 +++++++++++++++---------------
 pkg/types/events/events.proto      |  2 +-
 test/integration/nats/nats_test.go | 11 +++--
 11 files changed, 113 insertions(+), 92 deletions(-)
 delete mode 100644 pkg/types/aggregates/aggregates.go

diff --git a/pkg/api/task.go b/pkg/api/task.go
index 511908d6..f8c1d9af 100644
--- a/pkg/api/task.go
+++ b/pkg/api/task.go
@@ -53,7 +53,7 @@ func (ap *Task) Invoke(spec *types.TaskInvocationSpec) (*types.TaskInvocation, e
 
 	aggregate := aggregates.NewWorkflowInvocationAggregate(spec.InvocationId)
 	event, err := fes.NewEvent(*aggregates.NewTaskInvocationAggregate(taskID), &events.TaskStarted{
-		Task: task,
+		Spec: spec,
 	})
 	event.Parent = aggregate
 	if err != nil {
diff --git a/pkg/fes/fes.pb.go b/pkg/fes/fes.pb.go
index 999acf26..c14c981a 100644
--- a/pkg/fes/fes.pb.go
+++ b/pkg/fes/fes.pb.go
@@ -11,6 +11,7 @@ It has these top-level messages:
 	Aggregate
 	Event
 	EventHints
+	DummyEvent
 */
 package fes
 
@@ -136,33 +137,51 @@ func (m *EventHints) GetCompleted() bool {
 	return false
 }
 
+type DummyEvent struct {
+	Msg string `protobuf:"bytes,1,opt,name=msg" json:"msg,omitempty"`
+}
+
+func (m *DummyEvent) Reset()                    { *m = DummyEvent{} }
+func (m *DummyEvent) String() string            { return proto.CompactTextString(m) }
+func (*DummyEvent) ProtoMessage()               {}
+func (*DummyEvent) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{3} }
+
+func (m *DummyEvent) GetMsg() string {
+	if m != nil {
+		return m.Msg
+	}
+	return ""
+}
+
 func init() {
 	proto.RegisterType((*Aggregate)(nil), "fission.workflows.eventstore.Aggregate")
 	proto.RegisterType((*Event)(nil), "fission.workflows.eventstore.Event")
 	proto.RegisterType((*EventHints)(nil), "fission.workflows.eventstore.EventHints")
+	proto.RegisterType((*DummyEvent)(nil), "fission.workflows.eventstore.DummyEvent")
 }
 
 func init() { proto.RegisterFile("pkg/fes/fes.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
-	// 293 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x94, 0x90, 0x41, 0x4b, 0xc3, 0x30,
-	0x14, 0xc7, 0x59, 0xb7, 0x4e, 0xfb, 0x04, 0xc1, 0xe0, 0x21, 0x8e, 0x81, 0x63, 0x17, 0x8b, 0x87,
-	0x14, 0xf4, 0xe2, 0x49, 0x99, 0x30, 0xf0, 0x1c, 0x3c, 0x79, 0xcb, 0xec, 0x6b, 0x0c, 0x6b, 0x93,
-	0xd0, 0x44, 0x47, 0x3f, 0xa9, 0x5f, 0x47, 0x9a, 0xda, 0x15, 0x14, 0x86, 0x1e, 0x02, 0xe1, 0xe5,
-	0xf7, 0x7b, 0x79, 0xff, 0x07, 0x67, 0x76, 0x2b, 0xb3, 0x02, 0x5d, 0x7b, 0x98, 0xad, 0x8d, 0x37,
-	0x64, 0x5e, 0x28, 0xe7, 0x94, 0xd1, 0x6c, 0x67, 0xea, 0x6d, 0x51, 0x9a, 0x9d, 0x63, 0xf8, 0x81,
-	0xda, 0x3b, 0x6f, 0x6a, 0x9c, 0x5d, 0x4a, 0x63, 0x64, 0x89, 0x59, 0x60, 0x37, 0xef, 0x45, 0xe6,
-	0x55, 0x85, 0xce, 0x8b, 0xca, 0x76, 0xfa, 0xec, 0xe2, 0x27, 0x20, 0x74, 0xd3, 0x3d, 0x2d, 0x33,
-	0x48, 0x56, 0x52, 0xd6, 0x28, 0x85, 0x47, 0x72, 0x0a, 0x91, 0xca, 0xe9, 0x68, 0x31, 0x4a, 0x13,
-	0x1e, 0xa9, 0x9c, 0x10, 0x98, 0xf8, 0xc6, 0x22, 0x8d, 0x42, 0x25, 0xdc, 0x97, 0x9f, 0x11, 0xc4,
-	0xeb, 0xf6, 0xef, 0xbf, 0xd0, 0x64, 0x0d, 0x89, 0xe8, 0xdb, 0xd3, 0xf1, 0x62, 0x94, 0x9e, 0xdc,
-	0x5c, 0xb1, 0x43, 0x61, 0xd8, 0x7e, 0x1a, 0x3e, 0x98, 0xe4, 0x0e, 0x92, 0x7d, 0x26, 0x3a, 0x09,
-	0x6d, 0x66, 0xac, 0x0b, 0xc5, 0xfa, 0x50, 0xec, 0xb9, 0x27, 0xf8, 0x00, 0x93, 0x14, 0x26, 0xb9,
-	0xf0, 0x82, 0xc6, 0x41, 0x3a, 0xff, 0x25, 0xad, 0x74, 0xc3, 0x03, 0x41, 0x1e, 0x60, 0x6a, 0x45,
-	0x8d, 0xda, 0xd3, 0xe9, 0xff, 0xe6, 0xfc, 0xd6, 0xc8, 0x3d, 0xc4, 0x6f, 0x4a, 0x7b, 0x47, 0x8f,
-	0x82, 0x9f, 0x1e, 0xf6, 0xc3, 0x0e, 0x9f, 0x5a, 0x9e, 0x77, 0xda, 0xf2, 0x1a, 0x60, 0x28, 0x92,
-	0x39, 0x24, 0xaf, 0xa6, 0xb2, 0x25, 0x7a, 0xec, 0x96, 0x7c, 0xcc, 0x87, 0xc2, 0x63, 0xfc, 0x32,
-	0x2e, 0xd0, 0x6d, 0xa6, 0x21, 0xc7, 0xed, 0x57, 0x00, 0x00, 0x00, 0xff, 0xff, 0xce, 0x60, 0xbf,
-	0x26, 0x33, 0x02, 0x00, 0x00,
+	// 313 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x94, 0x91, 0x4f, 0x4b, 0xf3, 0x40,
+	0x10, 0x87, 0x69, 0xda, 0xf4, 0x7d, 0x33, 0x82, 0xe8, 0xe2, 0x61, 0x2d, 0x45, 0x4b, 0x2e, 0x06,
+	0x0f, 0x1b, 0xd0, 0x8b, 0x27, 0xa5, 0x62, 0xc1, 0x73, 0xf0, 0xe4, 0x6d, 0x6b, 0x27, 0x6b, 0x68,
+	0xf7, 0x0f, 0xd9, 0xad, 0x25, 0x9f, 0xd4, 0xaf, 0x23, 0xd9, 0x6d, 0x1b, 0x50, 0x28, 0x7a, 0x08,
+	0x2c, 0x93, 0xe7, 0xd9, 0x9d, 0xdf, 0x0c, 0x9c, 0x9a, 0xa5, 0xc8, 0x4b, 0xb4, 0xed, 0xc7, 0x4c,
+	0xad, 0x9d, 0x26, 0xe3, 0xb2, 0xb2, 0xb6, 0xd2, 0x8a, 0x6d, 0x74, 0xbd, 0x2c, 0x57, 0x7a, 0x63,
+	0x19, 0x7e, 0xa0, 0x72, 0xd6, 0xe9, 0x1a, 0x47, 0x97, 0x42, 0x6b, 0xb1, 0xc2, 0xdc, 0xb3, 0xf3,
+	0x75, 0x99, 0xbb, 0x4a, 0xa2, 0x75, 0x5c, 0x9a, 0xa0, 0x8f, 0xce, 0xbf, 0x03, 0x5c, 0x35, 0xe1,
+	0x57, 0x9a, 0x43, 0x32, 0x15, 0xa2, 0x46, 0xc1, 0x1d, 0x92, 0x63, 0x88, 0xaa, 0x05, 0xed, 0x4d,
+	0x7a, 0x59, 0x52, 0x44, 0xd5, 0x82, 0x10, 0x18, 0xb8, 0xc6, 0x20, 0x8d, 0x7c, 0xc5, 0x9f, 0xd3,
+	0xcf, 0x08, 0xe2, 0x59, 0xfb, 0xf6, 0x6f, 0x68, 0x32, 0x83, 0x84, 0xef, 0xae, 0xa7, 0xfd, 0x49,
+	0x2f, 0x3b, 0xba, 0xb9, 0x62, 0x87, 0xc2, 0xb0, 0x7d, 0x37, 0x45, 0x67, 0x92, 0x3b, 0x48, 0xf6,
+	0x99, 0xe8, 0xc0, 0x5f, 0x33, 0x62, 0x21, 0x14, 0xdb, 0x85, 0x62, 0x2f, 0x3b, 0xa2, 0xe8, 0x60,
+	0x92, 0xc1, 0x60, 0xc1, 0x1d, 0xa7, 0xb1, 0x97, 0xce, 0x7e, 0x48, 0x53, 0xd5, 0x14, 0x9e, 0x20,
+	0x0f, 0x30, 0x34, 0xbc, 0x46, 0xe5, 0xe8, 0xf0, 0x6f, 0x7d, 0x6e, 0x35, 0x72, 0x0f, 0xf1, 0x7b,
+	0xa5, 0x9c, 0xa5, 0xff, 0xbc, 0x9f, 0x1d, 0xf6, 0xfd, 0x0c, 0x9f, 0x5b, 0xbe, 0x08, 0x5a, 0x7a,
+	0x0d, 0xd0, 0x15, 0xc9, 0x18, 0x92, 0x37, 0x2d, 0xcd, 0x0a, 0x1d, 0x86, 0x21, 0xff, 0x2f, 0xba,
+	0x42, 0x7a, 0x01, 0xf0, 0xb4, 0x96, 0xb2, 0x09, 0x9b, 0x38, 0x81, 0xbe, 0xb4, 0x62, 0xbb, 0x8a,
+	0xf6, 0xf8, 0x18, 0xbf, 0xf6, 0x4b, 0xb4, 0xf3, 0xa1, 0xcf, 0x79, 0xfb, 0x15, 0x00, 0x00, 0xff,
+	0xff, 0xdc, 0xbf, 0x40, 0x6a, 0x53, 0x02, 0x00, 0x00,
 }
diff --git a/pkg/fes/fes.proto b/pkg/fes/fes.proto
index fbfa2c0d..4759815b 100644
--- a/pkg/fes/fes.proto
+++ b/pkg/fes/fes.proto
@@ -25,3 +25,7 @@ message Event {
 message EventHints {
     bool completed = 1;
 }
+
+message DummyEvent {
+    string msg = 1;
+}
\ No newline at end of file
diff --git a/pkg/fes/util.go b/pkg/fes/util.go
index b0f1ca42..13279b35 100644
--- a/pkg/fes/util.go
+++ b/pkg/fes/util.go
@@ -39,12 +39,10 @@ func (df *DeepFoldMatcher) Match(target string) bool {
 	return strings.EqualFold(df.Expected, target)
 }
 
-type ContainsMatcher struct {
-	Substr string
-}
-
-func (cm *ContainsMatcher) Match(target string) bool {
-	return strings.Contains(target, cm.Substr)
+func ContainsMatcher(Substr string) StringMatcher {
+	return func(target string) bool {
+		return strings.Contains(target, Substr)
+	}
 }
 
 func NewAggregate(entityType string, entityID string) Aggregate {
@@ -62,13 +60,15 @@ type EventOpts struct {
 
 func NewEvent(aggregate Aggregate, msg proto.Message) (*Event, error) {
 	var data *any.Any
-	if msg != nil {
-		d, err := ptypes.MarshalAny(msg)
-		if err != nil {
-			return nil, err
-		}
-		data = d
+	if msg == nil {
+		return nil, errors.New("event cannot have no message")
 	}
+
+	d, err := ptypes.MarshalAny(msg)
+	if err != nil {
+		return nil, err
+	}
+	data = d
 	return &Event{
 		Aggregate: &aggregate,
 		Data:      data,
@@ -88,3 +88,12 @@ func validateAggregate(aggregate Aggregate) error {
 
 	return nil
 }
+
+func UnmarshalEventData(event *Event) (interface{}, error) {
+	d := &ptypes.DynamicAny{}
+	err := ptypes.UnmarshalAny(event.Data, d)
+	if err != nil {
+		return nil, err
+	}
+	return d.Message, nil
+}
diff --git a/pkg/types/aggregates/aggregates.go b/pkg/types/aggregates/aggregates.go
deleted file mode 100644
index a24eb6ca..00000000
--- a/pkg/types/aggregates/aggregates.go
+++ /dev/null
@@ -1,15 +0,0 @@
-package aggregates
-
-import (
-	"github.com/fission/fission-workflows/pkg/fes"
-	"github.com/golang/protobuf/ptypes"
-)
-
-func unmarshalEventData(event *fes.Event) (interface{}, error) {
-	d := &ptypes.DynamicAny{}
-	err := ptypes.UnmarshalAny(event.Data, d)
-	if err != nil {
-		return nil, err
-	}
-	return d.Message, nil
-}
diff --git a/pkg/types/aggregates/invocation.go b/pkg/types/aggregates/invocation.go
index 40802b66..f298830f 100644
--- a/pkg/types/aggregates/invocation.go
+++ b/pkg/types/aggregates/invocation.go
@@ -42,7 +42,7 @@ func (wi *WorkflowInvocation) ApplyEvent(event *fes.Event) error {
 		return wi.applyTaskEvent(event)
 	}
 
-	eventData, err := unmarshalEventData(event)
+	eventData, err := fes.UnmarshalEventData(event)
 	if err != nil {
 		return err
 	}
diff --git a/pkg/types/aggregates/task.go b/pkg/types/aggregates/task.go
index b06535e9..70f69469 100644
--- a/pkg/types/aggregates/task.go
+++ b/pkg/types/aggregates/task.go
@@ -36,17 +36,16 @@ func NewTaskInvocationAggregate(id string) *fes.Aggregate {
 
 func (ti *TaskInvocation) ApplyEvent(event *fes.Event) error {
 
-	eventData, err := unmarshalEventData(event)
+	eventData, err := fes.UnmarshalEventData(event)
 	if err != nil {
 		return err
 	}
 
 	switch m := eventData.(type) {
 	case *events.TaskStarted:
-		task := m.GetTask()
 		ti.TaskInvocation = &types.TaskInvocation{
-			Metadata: task.GetMetadata(),
-			Spec:     task.GetSpec(),
+			Metadata: types.NewObjectMetadata(m.GetSpec().TaskId),
+			Spec:     m.GetSpec(),
 			Status: &types.TaskInvocationStatus{
 				Status:    types.TaskInvocationStatus_IN_PROGRESS,
 				UpdatedAt: event.Timestamp,
diff --git a/pkg/types/aggregates/workflow.go b/pkg/types/aggregates/workflow.go
index 0641f088..ee124db5 100644
--- a/pkg/types/aggregates/workflow.go
+++ b/pkg/types/aggregates/workflow.go
@@ -35,7 +35,7 @@ func NewWorkflowAggregate(workflowID string) *fes.Aggregate {
 }
 
 func (wf *Workflow) ApplyEvent(event *fes.Event) error {
-	eventData, err := unmarshalEventData(event)
+	eventData, err := fes.UnmarshalEventData(event)
 	if err != nil {
 		return err
 	}
diff --git a/pkg/types/events/events.pb.go b/pkg/types/events/events.pb.go
index d56cd310..29d779ca 100644
--- a/pkg/types/events/events.pb.go
+++ b/pkg/types/events/events.pb.go
@@ -198,7 +198,7 @@ func (m *InvocationFailed) GetError() *fission_workflows_types.Error {
 //
 // TODO why do we need task, and not just task spec.
 type TaskStarted struct {
-	Task *fission_workflows_types.TaskInvocation `protobuf:"bytes,1,opt,name=task" json:"task,omitempty"`
+	Spec *fission_workflows_types.TaskInvocationSpec `protobuf:"bytes,1,opt,name=spec" json:"spec,omitempty"`
 }
 
 func (m *TaskStarted) Reset()                    { *m = TaskStarted{} }
@@ -206,9 +206,9 @@ func (m *TaskStarted) String() string            { return proto.CompactTextStrin
 func (*TaskStarted) ProtoMessage()               {}
 func (*TaskStarted) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{10} }
 
-func (m *TaskStarted) GetTask() *fission_workflows_types.TaskInvocation {
+func (m *TaskStarted) GetSpec() *fission_workflows_types.TaskInvocationSpec {
 	if m != nil {
-		return m.Task
+		return m.Spec
 	}
 	return nil
 }
@@ -273,35 +273,35 @@ func init() {
 func init() { proto.RegisterFile("pkg/types/events/events.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
-	// 471 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x94, 0x51, 0x6b, 0xd4, 0x40,
-	0x14, 0x85, 0x49, 0xdb, 0x5d, 0xf4, 0xae, 0xd5, 0x76, 0x44, 0x58, 0x0a, 0x95, 0x65, 0x44, 0xec,
-	0x4b, 0x13, 0x6c, 0x7d, 0xb0, 0xf5, 0xc9, 0xd6, 0x48, 0x5b, 0x14, 0x24, 0x95, 0x56, 0x04, 0x1f,
-	0xa6, 0x99, 0xdb, 0x35, 0x24, 0xcd, 0x0c, 0x33, 0x93, 0x2d, 0xf9, 0x6b, 0xfe, 0x3a, 0x99, 0xcc,
-	0xa4, 0x49, 0x91, 0x5d, 0xc5, 0x7d, 0xc9, 0x84, 0xc9, 0xbd, 0x5f, 0xce, 0x39, 0x77, 0x12, 0xd8,
-	0x96, 0xf9, 0x34, 0x32, 0xb5, 0x44, 0x1d, 0xe1, 0x0c, 0x4b, 0xd3, 0x2e, 0xa1, 0x54, 0xc2, 0x08,
-	0x32, 0xbe, 0xce, 0xb4, 0xce, 0x44, 0x19, 0xde, 0x0a, 0x95, 0x5f, 0x17, 0xe2, 0x56, 0x87, 0xee,
-	0xf9, 0xd6, 0xe1, 0x34, 0x33, 0x3f, 0xab, 0xab, 0x30, 0x15, 0x37, 0x91, 0x2f, 0x6a, 0xd7, 0xdd,
-	0xbb, 0xe2, 0xa8, 0xa3, 0x37, 0x57, 0x47, 0xa5, 0x13, 0x78, 0x14, 0x5b, 0xca, 0xa5, 0x62, 0x52,
-	0xa2, 0x22, 0x1b, 0xb0, 0xca, 0xca, 0x7a, 0x1c, 0x4c, 0x82, 0x9d, 0x87, 0x89, 0xbd, 0xa5, 0x9f,
-	0xe0, 0xc9, 0xa5, 0x87, 0x1c, 0x2b, 0x64, 0x06, 0x39, 0x39, 0x80, 0x35, 0x2d, 0x31, 0x6d, 0xaa,
-	0x46, 0x7b, 0x2f, 0xc3, 0x3f, 0x95, 0xb9, 0x57, 0xb4, 0x7d, 0xe7, 0x12, 0xd3, 0xa4, 0x69, 0xa1,
-	0x9b, 0x1d, 0xed, 0x03, 0x16, 0x68, 0x90, 0xd3, 0x5f, 0x01, 0x3c, 0x6e, 0xf7, 0xbe, 0x30, 0xa5,
-	0x91, 0x93, 0x53, 0x18, 0x18, 0xa6, 0x73, 0x3d, 0x0e, 0x26, 0xab, 0x3b, 0xa3, 0xbd, 0xfd, 0x70,
-	0x9e, 0xf7, 0xf0, 0x7e, 0x63, 0xf8, 0xd5, 0x76, 0xc5, 0xa5, 0x51, 0x75, 0xe2, 0x08, 0x5b, 0x3f,
-	0x00, 0xba, 0x4d, 0x6b, 0x2f, 0xc7, 0x3b, 0x7b, 0x39, 0xd6, 0xe4, 0x00, 0x06, 0x33, 0x56, 0x54,
-	0x38, 0x5e, 0x69, 0xcc, 0xbc, 0x98, 0x6b, 0xc6, 0x52, 0xce, 0x0d, 0x33, 0x95, 0x4e, 0x5c, 0xc7,
-	0xe1, 0xca, 0xdb, 0x80, 0x7e, 0x86, 0x67, 0x7d, 0x09, 0x59, 0x39, 0xfd, 0xc8, 0xb2, 0x02, 0x39,
-	0x79, 0x03, 0x03, 0x54, 0x4a, 0x28, 0x1f, 0xd2, 0xf3, 0xb9, 0xdc, 0xd8, 0x56, 0x25, 0xae, 0x98,
-	0x7e, 0x83, 0xcd, 0xd3, 0x72, 0x26, 0x52, 0x66, 0x32, 0x51, 0xb6, 0x71, 0x1f, 0xdf, 0x8b, 0x3b,
-	0xfa, 0x6b, 0xdc, 0x1d, 0xa1, 0x17, 0x7c, 0x02, 0x4f, 0x7b, 0x64, 0x71, 0x23, 0x9b, 0xf0, 0xc9,
-	0x3b, 0x18, 0x8a, 0xca, 0xc8, 0xca, 0x78, 0xfa, 0x02, 0xff, 0xb5, 0x44, 0x7e, 0x61, 0x8d, 0x27,
-	0xbe, 0x85, 0x9e, 0x01, 0xe9, 0x31, 0x59, 0x99, 0xe2, 0xff, 0x3b, 0x3f, 0xe9, 0xeb, 0xb3, 0x59,
-	0xbf, 0xe7, 0x1c, 0x39, 0x79, 0x0d, 0x6b, 0x76, 0x8e, 0x9e, 0xb5, 0xbd, 0x70, 0x3a, 0x49, 0x53,
-	0x4a, 0x4f, 0x60, 0xa3, 0x23, 0x2d, 0x35, 0x8d, 0x33, 0x18, 0xf9, 0xa9, 0x2b, 0x97, 0x55, 0x5f,
-	0xcb, 0xab, 0x85, 0x5a, 0x3a, 0x05, 0x5e, 0xd5, 0x05, 0xac, 0x37, 0xac, 0x2a, 0x4d, 0x11, 0xad,
-	0xb3, 0x18, 0x86, 0x0a, 0x75, 0x55, 0xb4, 0xc9, 0xef, 0xfe, 0x23, 0xcf, 0x9f, 0x41, 0xdf, 0x4c,
-	0xd7, 0xbd, 0xc6, 0x3c, 0x93, 0x12, 0x39, 0x3d, 0x72, 0xc7, 0x7d, 0x19, 0xdb, 0x47, 0x0f, 0xbe,
-	0x0f, 0xdd, 0xd7, 0x75, 0x35, 0x6c, 0x7e, 0x12, 0xfb, 0xbf, 0x03, 0x00, 0x00, 0xff, 0xff, 0x37,
-	0x39, 0x48, 0x43, 0x9b, 0x04, 0x00, 0x00,
+	// 472 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x94, 0xe1, 0x6b, 0xd4, 0x30,
+	0x18, 0xc6, 0xe9, 0xb6, 0x3b, 0xf4, 0x3d, 0xa7, 0x5b, 0x44, 0x38, 0x06, 0x93, 0x23, 0x22, 0x0c,
+	0x64, 0x2d, 0x6e, 0x7e, 0x70, 0xf3, 0x83, 0xb8, 0x79, 0xb2, 0x89, 0x8a, 0x74, 0xb2, 0x89, 0xe0,
+	0x87, 0xac, 0x79, 0x77, 0x96, 0x76, 0x4d, 0x48, 0xd2, 0x1b, 0xfd, 0xd7, 0xfc, 0xeb, 0x24, 0x4d,
+	0xba, 0xf6, 0xd0, 0x3b, 0xc5, 0xfb, 0xd2, 0x94, 0xf4, 0x7d, 0x7e, 0x7d, 0x9f, 0xe7, 0x4d, 0x0b,
+	0xdb, 0x32, 0x9b, 0x44, 0xa6, 0x92, 0xa8, 0x23, 0x9c, 0x62, 0x61, 0x9a, 0x25, 0x94, 0x4a, 0x18,
+	0x41, 0x86, 0x57, 0xa9, 0xd6, 0xa9, 0x28, 0xc2, 0x1b, 0xa1, 0xb2, 0xab, 0x5c, 0xdc, 0xe8, 0xd0,
+	0x3d, 0xdf, 0x3a, 0x9c, 0xa4, 0xe6, 0x47, 0x79, 0x19, 0x26, 0xe2, 0x3a, 0xf2, 0x45, 0xcd, 0xba,
+	0x7b, 0x5b, 0x1c, 0xb5, 0xf4, 0xfa, 0xea, 0xa8, 0x74, 0x04, 0xf7, 0xc6, 0x96, 0x72, 0xa1, 0x98,
+	0x94, 0xa8, 0xc8, 0x06, 0xac, 0xb2, 0xa2, 0x1a, 0x06, 0xa3, 0x60, 0xe7, 0x6e, 0x6c, 0x6f, 0xe9,
+	0x07, 0x78, 0x70, 0xe1, 0x21, 0xc7, 0x0a, 0x99, 0x41, 0x4e, 0x0e, 0x60, 0x4d, 0x4b, 0x4c, 0xea,
+	0xaa, 0xc1, 0xde, 0xd3, 0xf0, 0xf7, 0xce, 0xdc, 0x2b, 0x1a, 0xdd, 0x99, 0xc4, 0x24, 0xae, 0x25,
+	0x74, 0xb3, 0xa5, 0xbd, 0xc5, 0x1c, 0x0d, 0x72, 0xfa, 0x33, 0x80, 0xfb, 0xcd, 0xde, 0x67, 0xa6,
+	0x34, 0x72, 0x72, 0x0a, 0x3d, 0xc3, 0x74, 0xa6, 0x87, 0xc1, 0x68, 0x75, 0x67, 0xb0, 0xb7, 0x1f,
+	0xce, 0xf3, 0x1e, 0xce, 0x0a, 0xc3, 0x2f, 0x56, 0x35, 0x2e, 0x8c, 0xaa, 0x62, 0x47, 0xd8, 0xfa,
+	0x0e, 0xd0, 0x6e, 0x5a, 0x7b, 0x19, 0xde, 0xda, 0xcb, 0xb0, 0x22, 0x07, 0xd0, 0x9b, 0xb2, 0xbc,
+	0xc4, 0xe1, 0x4a, 0x6d, 0xe6, 0xc9, 0x5c, 0x33, 0x96, 0x72, 0x66, 0x98, 0x29, 0x75, 0xec, 0x14,
+	0x87, 0x2b, 0x2f, 0x03, 0xfa, 0x11, 0x1e, 0x75, 0x5b, 0x48, 0x8b, 0xc9, 0x3b, 0x96, 0xe6, 0xc8,
+	0xc9, 0x0b, 0xe8, 0xa1, 0x52, 0x42, 0xf9, 0x90, 0x1e, 0xcf, 0xe5, 0x8e, 0x6d, 0x55, 0xec, 0x8a,
+	0xe9, 0x57, 0xd8, 0x3c, 0x2d, 0xa6, 0x22, 0x61, 0x26, 0x15, 0x45, 0x13, 0xf7, 0xf1, 0x4c, 0xdc,
+	0xd1, 0x5f, 0xe3, 0x6e, 0x09, 0x9d, 0xe0, 0x63, 0x78, 0xd8, 0x21, 0x8b, 0x6b, 0x59, 0x87, 0x4f,
+	0x5e, 0x41, 0x5f, 0x94, 0x46, 0x96, 0xc6, 0xd3, 0x17, 0xf8, 0xaf, 0x24, 0xf2, 0x73, 0x6b, 0x3c,
+	0xf6, 0x12, 0xfa, 0x1e, 0x48, 0x87, 0xc9, 0x8a, 0x04, 0xff, 0xdf, 0xf9, 0x49, 0xb7, 0x3f, 0x9b,
+	0xf5, 0x1b, 0xce, 0x91, 0x93, 0xe7, 0xb0, 0x66, 0xe7, 0xe8, 0x59, 0xdb, 0x0b, 0xa7, 0x13, 0xd7,
+	0xa5, 0xf4, 0x04, 0x36, 0x5a, 0xd2, 0x52, 0xd3, 0xf8, 0x04, 0x03, 0x3f, 0x75, 0x65, 0xb3, 0x7a,
+	0x3d, 0x33, 0x87, 0x67, 0x0b, 0x7b, 0xf9, 0xe3, 0x0c, 0xce, 0x61, 0xbd, 0xe6, 0x95, 0x49, 0x82,
+	0x68, 0xdd, 0x8d, 0xa1, 0xaf, 0x50, 0x97, 0x79, 0x93, 0xfe, 0xee, 0xbf, 0x32, 0xdd, 0x39, 0xf4,
+	0x62, 0xba, 0xee, 0xfb, 0xcc, 0x52, 0x29, 0x91, 0xd3, 0x23, 0x77, 0xe4, 0x97, 0xb1, 0x7e, 0x74,
+	0xe7, 0x5b, 0xdf, 0x7d, 0x61, 0x97, 0xfd, 0xfa, 0x47, 0xb1, 0xff, 0x2b, 0x00, 0x00, 0xff, 0xff,
+	0xeb, 0xca, 0x91, 0xa1, 0x9f, 0x04, 0x00, 0x00,
 }
diff --git a/pkg/types/events/events.proto b/pkg/types/events/events.proto
index 2c5ae420..9bbdb82e 100644
--- a/pkg/types/events/events.proto
+++ b/pkg/types/events/events.proto
@@ -57,7 +57,7 @@ message InvocationFailed {
 //
 // TODO why do we need task, and not just task spec.
 message TaskStarted {
-    fission.workflows.types.TaskInvocation task = 1;
+    fission.workflows.types.TaskInvocationSpec spec = 1;
 }
 
 message TaskSucceeded {
diff --git a/test/integration/nats/nats_test.go b/test/integration/nats/nats_test.go
index 36748f71..f23000ce 100644
--- a/test/integration/nats/nats_test.go
+++ b/test/integration/nats/nats_test.go
@@ -91,8 +91,10 @@ func TestNatsBackend_GetNonExistent(t *testing.T) {
 
 func TestNatsBackend_Append(t *testing.T) {
 	key := fes.NewAggregate("someType", "someId")
-	event := fes.NewEvent(key, nil)
-	err := backend.Append(event)
+	dummyEvent := &fes.DummyEvent{Msg: "dummy"}
+	event, err := fes.NewEvent(key, dummyEvent)
+	assert.NoError(t, err)
+	err = backend.Append(event)
 	assert.NoError(t, err)
 
 	// check
@@ -101,10 +103,13 @@ func TestNatsBackend_Append(t *testing.T) {
 	assert.Len(t, events, 1)
 	event.Id = "1"
 	assert.Equal(t, event, events[0])
+	data, err := fes.UnmarshalEventData(events[0])
+	assert.NoError(t, err)
+	assert.Equal(t, dummyEvent, data)
 }
 
 func TestNatsBackend_List(t *testing.T) {
-	subjects, err := backend.List(&fes.ContainsMatcher{})
+	subjects, err := backend.List(fes.ContainsMatcher(""))
 	assert.NoError(t, err)
 	assert.NotEmpty(t, subjects)
 }

From ecf3fd0204eae12824dde2236f642f4737ee9cd4 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Tue, 17 Jul 2018 16:32:50 +0200
Subject: [PATCH 06/10] Moved events and aggregate definitions to API

---
 cmd/fission-workflows-bundle/bundle/bundle.go |  2 +-
 pkg/{types => api}/aggregates/invocation.go   |  2 +-
 pkg/{types => api}/aggregates/task.go         |  2 +-
 pkg/{types => api}/aggregates/workflow.go     |  2 +-
 pkg/api/events/events.go                      | 14 ++++
 pkg/{types => api}/events/events.pb.go        | 67 +++++++++----------
 pkg/{types => api}/events/events.proto        |  2 +-
 pkg/api/invocation.go                         |  4 +-
 pkg/api/task.go                               |  4 +-
 pkg/api/workflow.go                           |  4 +-
 pkg/apiserver/invocation.go                   |  2 +-
 pkg/apiserver/workflow.go                     |  2 +-
 pkg/controller/invocation/controller.go       |  2 +-
 pkg/controller/workflow/controller.go         |  2 +-
 pkg/fes/util.go                               |  4 +-
 pkg/fnenv/workflows/workflows.go              | 14 ++--
 16 files changed, 74 insertions(+), 55 deletions(-)
 rename pkg/{types => api}/aggregates/invocation.go (98%)
 rename pkg/{types => api}/aggregates/task.go (97%)
 rename pkg/{types => api}/aggregates/workflow.go (97%)
 create mode 100644 pkg/api/events/events.go
 rename pkg/{types => api}/events/events.pb.go (76%)
 rename pkg/{types => api}/events/events.proto (94%)

diff --git a/cmd/fission-workflows-bundle/bundle/bundle.go b/cmd/fission-workflows-bundle/bundle/bundle.go
index d7f684c2..66860670 100644
--- a/cmd/fission-workflows-bundle/bundle/bundle.go
+++ b/cmd/fission-workflows-bundle/bundle/bundle.go
@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/fission/fission-workflows/pkg/api"
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
 	"github.com/fission/fission-workflows/pkg/apiserver"
 	"github.com/fission/fission-workflows/pkg/controller"
 	"github.com/fission/fission-workflows/pkg/controller/expr"
@@ -23,7 +24,6 @@ import (
 	"github.com/fission/fission-workflows/pkg/fnenv/native/builtin"
 	"github.com/fission/fission-workflows/pkg/fnenv/workflows"
 	"github.com/fission/fission-workflows/pkg/scheduler"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
 	"github.com/fission/fission-workflows/pkg/util"
 	"github.com/fission/fission-workflows/pkg/util/labels"
 	"github.com/fission/fission-workflows/pkg/util/pubsub"
diff --git a/pkg/types/aggregates/invocation.go b/pkg/api/aggregates/invocation.go
similarity index 98%
rename from pkg/types/aggregates/invocation.go
rename to pkg/api/aggregates/invocation.go
index f298830f..94297c34 100644
--- a/pkg/types/aggregates/invocation.go
+++ b/pkg/api/aggregates/invocation.go
@@ -3,9 +3,9 @@ package aggregates
 import (
 	"errors"
 
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/golang/protobuf/proto"
 	log "github.com/sirupsen/logrus"
 )
diff --git a/pkg/types/aggregates/task.go b/pkg/api/aggregates/task.go
similarity index 97%
rename from pkg/types/aggregates/task.go
rename to pkg/api/aggregates/task.go
index 70f69469..8607bbc7 100644
--- a/pkg/types/aggregates/task.go
+++ b/pkg/api/aggregates/task.go
@@ -1,9 +1,9 @@
 package aggregates
 
 import (
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/golang/protobuf/proto"
 	log "github.com/sirupsen/logrus"
 )
diff --git a/pkg/types/aggregates/workflow.go b/pkg/api/aggregates/workflow.go
similarity index 97%
rename from pkg/types/aggregates/workflow.go
rename to pkg/api/aggregates/workflow.go
index ee124db5..0762b1c8 100644
--- a/pkg/types/aggregates/workflow.go
+++ b/pkg/api/aggregates/workflow.go
@@ -1,9 +1,9 @@
 package aggregates
 
 import (
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/golang/protobuf/proto"
 	log "github.com/sirupsen/logrus"
 )
diff --git a/pkg/api/events/events.go b/pkg/api/events/events.go
new file mode 100644
index 00000000..3b7e8eeb
--- /dev/null
+++ b/pkg/api/events/events.go
@@ -0,0 +1,14 @@
+package events
+
+import (
+	"reflect"
+
+	"github.com/golang/protobuf/proto"
+)
+
+func TypeOf(event proto.Message) string {
+	if event == nil {
+		return ""
+	}
+	return reflect.Indirect(reflect.ValueOf(event)).Type().Name()
+}
diff --git a/pkg/types/events/events.pb.go b/pkg/api/events/events.pb.go
similarity index 76%
rename from pkg/types/events/events.pb.go
rename to pkg/api/events/events.pb.go
index 29d779ca..9a253d2e 100644
--- a/pkg/types/events/events.pb.go
+++ b/pkg/api/events/events.pb.go
@@ -1,11 +1,11 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
-// source: pkg/types/events/events.proto
+// source: pkg/api/events/events.proto
 
 /*
 Package events is a generated protocol buffer package.
 
 It is generated from these files:
-	pkg/types/events/events.proto
+	pkg/api/events/events.proto
 
 It has these top-level messages:
 	EventWrapper
@@ -28,7 +28,7 @@ package events
 import proto "github.com/golang/protobuf/proto"
 import fmt "fmt"
 import math "math"
-import fission_workflows_types "github.com/fission/fission-workflows/pkg/types"
+import fission_workflows_types "pkg/types"
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -270,38 +270,37 @@ func init() {
 	proto.RegisterType((*TaskFailed)(nil), "fission.workflows.events.TaskFailed")
 }
 
-func init() { proto.RegisterFile("pkg/types/events/events.proto", fileDescriptor0) }
+func init() { proto.RegisterFile("pkg/api/events/events.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
-	// 472 bytes of a gzipped FileDescriptorProto
+	// 458 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x94, 0xe1, 0x6b, 0xd4, 0x30,
-	0x18, 0xc6, 0xe9, 0xb6, 0x3b, 0xf4, 0x3d, 0xa7, 0x5b, 0x44, 0x38, 0x06, 0x93, 0x23, 0x22, 0x0c,
-	0x64, 0x2d, 0x6e, 0x7e, 0x70, 0xf3, 0x83, 0xb8, 0x79, 0xb2, 0x89, 0x8a, 0x74, 0xb2, 0x89, 0xe0,
-	0x87, 0xac, 0x79, 0x77, 0x96, 0x76, 0x4d, 0x48, 0xd2, 0x1b, 0xfd, 0xd7, 0xfc, 0xeb, 0x24, 0x4d,
-	0xba, 0xf6, 0xd0, 0x3b, 0xc5, 0xfb, 0xd2, 0x94, 0xf4, 0x7d, 0x7e, 0x7d, 0x9f, 0xe7, 0x4d, 0x0b,
-	0xdb, 0x32, 0x9b, 0x44, 0xa6, 0x92, 0xa8, 0x23, 0x9c, 0x62, 0x61, 0x9a, 0x25, 0x94, 0x4a, 0x18,
-	0x41, 0x86, 0x57, 0xa9, 0xd6, 0xa9, 0x28, 0xc2, 0x1b, 0xa1, 0xb2, 0xab, 0x5c, 0xdc, 0xe8, 0xd0,
-	0x3d, 0xdf, 0x3a, 0x9c, 0xa4, 0xe6, 0x47, 0x79, 0x19, 0x26, 0xe2, 0x3a, 0xf2, 0x45, 0xcd, 0xba,
-	0x7b, 0x5b, 0x1c, 0xb5, 0xf4, 0xfa, 0xea, 0xa8, 0x74, 0x04, 0xf7, 0xc6, 0x96, 0x72, 0xa1, 0x98,
-	0x94, 0xa8, 0xc8, 0x06, 0xac, 0xb2, 0xa2, 0x1a, 0x06, 0xa3, 0x60, 0xe7, 0x6e, 0x6c, 0x6f, 0xe9,
-	0x07, 0x78, 0x70, 0xe1, 0x21, 0xc7, 0x0a, 0x99, 0x41, 0x4e, 0x0e, 0x60, 0x4d, 0x4b, 0x4c, 0xea,
-	0xaa, 0xc1, 0xde, 0xd3, 0xf0, 0xf7, 0xce, 0xdc, 0x2b, 0x1a, 0xdd, 0x99, 0xc4, 0x24, 0xae, 0x25,
-	0x74, 0xb3, 0xa5, 0xbd, 0xc5, 0x1c, 0x0d, 0x72, 0xfa, 0x33, 0x80, 0xfb, 0xcd, 0xde, 0x67, 0xa6,
-	0x34, 0x72, 0x72, 0x0a, 0x3d, 0xc3, 0x74, 0xa6, 0x87, 0xc1, 0x68, 0x75, 0x67, 0xb0, 0xb7, 0x1f,
-	0xce, 0xf3, 0x1e, 0xce, 0x0a, 0xc3, 0x2f, 0x56, 0x35, 0x2e, 0x8c, 0xaa, 0x62, 0x47, 0xd8, 0xfa,
-	0x0e, 0xd0, 0x6e, 0x5a, 0x7b, 0x19, 0xde, 0xda, 0xcb, 0xb0, 0x22, 0x07, 0xd0, 0x9b, 0xb2, 0xbc,
-	0xc4, 0xe1, 0x4a, 0x6d, 0xe6, 0xc9, 0x5c, 0x33, 0x96, 0x72, 0x66, 0x98, 0x29, 0x75, 0xec, 0x14,
-	0x87, 0x2b, 0x2f, 0x03, 0xfa, 0x11, 0x1e, 0x75, 0x5b, 0x48, 0x8b, 0xc9, 0x3b, 0x96, 0xe6, 0xc8,
-	0xc9, 0x0b, 0xe8, 0xa1, 0x52, 0x42, 0xf9, 0x90, 0x1e, 0xcf, 0xe5, 0x8e, 0x6d, 0x55, 0xec, 0x8a,
-	0xe9, 0x57, 0xd8, 0x3c, 0x2d, 0xa6, 0x22, 0x61, 0x26, 0x15, 0x45, 0x13, 0xf7, 0xf1, 0x4c, 0xdc,
-	0xd1, 0x5f, 0xe3, 0x6e, 0x09, 0x9d, 0xe0, 0x63, 0x78, 0xd8, 0x21, 0x8b, 0x6b, 0x59, 0x87, 0x4f,
-	0x5e, 0x41, 0x5f, 0x94, 0x46, 0x96, 0xc6, 0xd3, 0x17, 0xf8, 0xaf, 0x24, 0xf2, 0x73, 0x6b, 0x3c,
-	0xf6, 0x12, 0xfa, 0x1e, 0x48, 0x87, 0xc9, 0x8a, 0x04, 0xff, 0xdf, 0xf9, 0x49, 0xb7, 0x3f, 0x9b,
-	0xf5, 0x1b, 0xce, 0x91, 0x93, 0xe7, 0xb0, 0x66, 0xe7, 0xe8, 0x59, 0xdb, 0x0b, 0xa7, 0x13, 0xd7,
-	0xa5, 0xf4, 0x04, 0x36, 0x5a, 0xd2, 0x52, 0xd3, 0xf8, 0x04, 0x03, 0x3f, 0x75, 0x65, 0xb3, 0x7a,
-	0x3d, 0x33, 0x87, 0x67, 0x0b, 0x7b, 0xf9, 0xe3, 0x0c, 0xce, 0x61, 0xbd, 0xe6, 0x95, 0x49, 0x82,
-	0x68, 0xdd, 0x8d, 0xa1, 0xaf, 0x50, 0x97, 0x79, 0x93, 0xfe, 0xee, 0xbf, 0x32, 0xdd, 0x39, 0xf4,
-	0x62, 0xba, 0xee, 0xfb, 0xcc, 0x52, 0x29, 0x91, 0xd3, 0x23, 0x77, 0xe4, 0x97, 0xb1, 0x7e, 0x74,
-	0xe7, 0x5b, 0xdf, 0x7d, 0x61, 0x97, 0xfd, 0xfa, 0x47, 0xb1, 0xff, 0x2b, 0x00, 0x00, 0xff, 0xff,
-	0xeb, 0xca, 0x91, 0xa1, 0x9f, 0x04, 0x00, 0x00,
+	0x18, 0xc6, 0xe9, 0xb6, 0x3b, 0xf4, 0x3d, 0xa7, 0x5b, 0x64, 0x70, 0x4c, 0x94, 0x23, 0x22, 0x0c,
+	0xc4, 0x1e, 0x6e, 0x7e, 0x70, 0xfa, 0x41, 0xdc, 0x3c, 0xd9, 0x44, 0x45, 0x32, 0xd9, 0x44, 0xf0,
+	0x43, 0x6c, 0xde, 0x8d, 0xd2, 0x9a, 0x84, 0x24, 0xbd, 0xd1, 0x7f, 0xcd, 0xbf, 0x4e, 0xd2, 0xe4,
+	0x6c, 0x0f, 0xbd, 0x53, 0xb6, 0x2f, 0x6d, 0x49, 0xdf, 0xe7, 0x97, 0xf7, 0x79, 0xde, 0xb4, 0x70,
+	0x4f, 0x17, 0x17, 0x63, 0xae, 0xf3, 0x31, 0x4e, 0x51, 0x3a, 0x1b, 0x6f, 0xa9, 0x36, 0xca, 0x29,
+	0x32, 0x3c, 0xcf, 0xad, 0xcd, 0x95, 0x4c, 0x2f, 0x95, 0x29, 0xce, 0x4b, 0x75, 0x69, 0xd3, 0xf0,
+	0x7e, 0x7b, 0xcb, 0xcb, 0x5c, 0xad, 0xd1, 0x86, 0x6b, 0x10, 0xd0, 0x11, 0xdc, 0x9a, 0xf8, 0x82,
+	0x33, 0xc3, 0xb5, 0x46, 0x43, 0x36, 0x60, 0x95, 0xcb, 0x7a, 0x98, 0x8c, 0x92, 0x9d, 0x9b, 0xcc,
+	0x3f, 0xd2, 0xf7, 0x70, 0xe7, 0x2c, 0xc2, 0x0e, 0x0d, 0x72, 0x87, 0x82, 0xec, 0xc3, 0x9a, 0xd5,
+	0x98, 0x35, 0x55, 0x83, 0xdd, 0x47, 0xe9, 0x9f, 0x9b, 0x86, 0x2d, 0x66, 0xba, 0x13, 0x8d, 0x19,
+	0x6b, 0x24, 0x74, 0xb3, 0xa5, 0xbd, 0xc1, 0x12, 0x1d, 0x0a, 0xfa, 0x33, 0x81, 0xdb, 0xb3, 0xb5,
+	0x4f, 0xdc, 0x58, 0x14, 0xe4, 0x18, 0x7a, 0x8e, 0xdb, 0xc2, 0x0e, 0x93, 0xd1, 0xea, 0xce, 0x60,
+	0x77, 0x2f, 0x5d, 0x64, 0x2b, 0x9d, 0x17, 0xa6, 0x9f, 0xbd, 0x6a, 0x22, 0x9d, 0xa9, 0x59, 0x20,
+	0x6c, 0x7f, 0x03, 0x68, 0x17, 0xbd, 0xbd, 0x02, 0x7f, 0xdb, 0x2b, 0xb0, 0x26, 0xfb, 0xd0, 0x9b,
+	0xf2, 0xb2, 0xc2, 0xe1, 0x4a, 0x63, 0xe6, 0xe1, 0x42, 0x33, 0x9e, 0x72, 0xe2, 0xb8, 0xab, 0x2c,
+	0x0b, 0x8a, 0x17, 0x2b, 0xcf, 0x13, 0xfa, 0x01, 0xb6, 0xba, 0x2d, 0xe4, 0xf2, 0xe2, 0x2d, 0xcf,
+	0x4b, 0x14, 0xe4, 0x19, 0xf4, 0xd0, 0x18, 0x65, 0x62, 0x48, 0x0f, 0x16, 0x72, 0x27, 0xbe, 0x8a,
+	0x85, 0x62, 0xfa, 0x05, 0x36, 0x8f, 0xe5, 0x54, 0x65, 0xdc, 0xe5, 0x4a, 0xce, 0xe2, 0x3e, 0x9c,
+	0x8b, 0x7b, 0xfc, 0xcf, 0xb8, 0x5b, 0x42, 0x27, 0x78, 0x06, 0x77, 0x3b, 0x64, 0xf5, 0x43, 0x37,
+	0xe1, 0x93, 0x97, 0xd0, 0x57, 0x95, 0xd3, 0x95, 0x8b, 0xf4, 0x25, 0xfe, 0x6b, 0x8d, 0xe2, 0xd4,
+	0x1b, 0x67, 0x51, 0x42, 0xdf, 0x01, 0xe9, 0x30, 0xb9, 0xcc, 0xf0, 0xea, 0xce, 0x8f, 0xba, 0xfd,
+	0xf9, 0xac, 0x5f, 0x0b, 0x81, 0x82, 0x3c, 0x85, 0x35, 0x3f, 0xc7, 0xc8, 0xba, 0xbf, 0x74, 0x3a,
+	0xac, 0x29, 0xa5, 0x47, 0xb0, 0xd1, 0x92, 0xae, 0x35, 0x8d, 0x8f, 0x30, 0x88, 0x53, 0x37, 0x3e,
+	0xab, 0x57, 0x73, 0x73, 0x78, 0xbc, 0xb4, 0x97, 0xbf, 0xce, 0xe0, 0x14, 0xd6, 0x1b, 0x5e, 0x95,
+	0x65, 0x88, 0xde, 0xdd, 0x04, 0xfa, 0x06, 0x6d, 0x55, 0xce, 0xd2, 0x7f, 0xf2, 0xbf, 0xcc, 0x70,
+	0x0e, 0xa3, 0x98, 0xae, 0xc7, 0x3e, 0x8b, 0x5c, 0x6b, 0x14, 0xf4, 0x20, 0x1c, 0xf9, 0xeb, 0x58,
+	0x3f, 0xb8, 0xf1, 0xb5, 0x1f, 0xbe, 0xb0, 0xef, 0xfd, 0xe6, 0x47, 0xb1, 0xf7, 0x2b, 0x00, 0x00,
+	0xff, 0xff, 0x8b, 0x11, 0x02, 0x03, 0x78, 0x04, 0x00, 0x00,
 }
diff --git a/pkg/types/events/events.proto b/pkg/api/events/events.proto
similarity index 94%
rename from pkg/types/events/events.proto
rename to pkg/api/events/events.proto
index 9bbdb82e..5ceac3fe 100644
--- a/pkg/types/events/events.proto
+++ b/pkg/api/events/events.proto
@@ -3,7 +3,7 @@ syntax = "proto3";
 package fission.workflows.events;
 option go_package = "events";
 
-import "github.com/fission/fission-workflows/pkg/types/types.proto";
+import "pkg/types/types.proto";
 
 message EventWrapper {
     string any = 1;
diff --git a/pkg/api/invocation.go b/pkg/api/invocation.go
index 06e624ac..bda22339 100644
--- a/pkg/api/invocation.go
+++ b/pkg/api/invocation.go
@@ -4,10 +4,10 @@ import (
 	"errors"
 	"fmt"
 
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/fission/fission-workflows/pkg/util"
 )
diff --git a/pkg/api/task.go b/pkg/api/task.go
index f8c1d9af..a99e4428 100644
--- a/pkg/api/task.go
+++ b/pkg/api/task.go
@@ -3,11 +3,11 @@ package api
 import (
 	"errors"
 
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/fnenv"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/types/typedvalues"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/golang/protobuf/ptypes"
diff --git a/pkg/api/workflow.go b/pkg/api/workflow.go
index 7fbd08a6..4104a5a5 100644
--- a/pkg/api/workflow.go
+++ b/pkg/api/workflow.go
@@ -4,11 +4,11 @@ import (
 	"errors"
 	"fmt"
 
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/fnenv"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/fission/fission-workflows/pkg/util"
 	"github.com/golang/protobuf/ptypes"
diff --git a/pkg/apiserver/invocation.go b/pkg/apiserver/invocation.go
index 99f3d3a1..10bdaced 100644
--- a/pkg/apiserver/invocation.go
+++ b/pkg/apiserver/invocation.go
@@ -4,10 +4,10 @@ import (
 	"errors"
 
 	"github.com/fission/fission-workflows/pkg/api"
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/fnenv/workflows"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/golang/protobuf/ptypes/empty"
 	"github.com/sirupsen/logrus"
diff --git a/pkg/apiserver/workflow.go b/pkg/apiserver/workflow.go
index afa28964..d8a5d75a 100644
--- a/pkg/apiserver/workflow.go
+++ b/pkg/apiserver/workflow.go
@@ -2,9 +2,9 @@ package apiserver
 
 import (
 	"github.com/fission/fission-workflows/pkg/api"
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/golang/protobuf/ptypes/empty"
 	"golang.org/x/net/context"
diff --git a/pkg/controller/invocation/controller.go b/pkg/controller/invocation/controller.go
index 3c784eba..4905ebf6 100644
--- a/pkg/controller/invocation/controller.go
+++ b/pkg/controller/invocation/controller.go
@@ -7,11 +7,11 @@ import (
 	"time"
 
 	"github.com/fission/fission-workflows/pkg/api"
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
 	"github.com/fission/fission-workflows/pkg/controller"
 	"github.com/fission/fission-workflows/pkg/controller/expr"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/scheduler"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
 	"github.com/fission/fission-workflows/pkg/util/labels"
 	"github.com/fission/fission-workflows/pkg/util/pubsub"
 	"github.com/golang/protobuf/ptypes"
diff --git a/pkg/controller/workflow/controller.go b/pkg/controller/workflow/controller.go
index 6050fc6b..ffe9d734 100644
--- a/pkg/controller/workflow/controller.go
+++ b/pkg/controller/workflow/controller.go
@@ -7,10 +7,10 @@ import (
 	"time"
 
 	"github.com/fission/fission-workflows/pkg/api"
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
 	"github.com/fission/fission-workflows/pkg/controller"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
 	"github.com/fission/fission-workflows/pkg/util/labels"
 	"github.com/fission/fission-workflows/pkg/util/pubsub"
 	"github.com/golang/protobuf/ptypes"
diff --git a/pkg/fes/util.go b/pkg/fes/util.go
index 13279b35..bca23455 100644
--- a/pkg/fes/util.go
+++ b/pkg/fes/util.go
@@ -2,10 +2,10 @@ package fes
 
 import (
 	"errors"
-	"reflect"
 	"strings"
 	"time"
 
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
 	"github.com/golang/protobuf/ptypes/any"
@@ -73,7 +73,7 @@ func NewEvent(aggregate Aggregate, msg proto.Message) (*Event, error) {
 		Aggregate: &aggregate,
 		Data:      data,
 		Timestamp: ptypes.TimestampNow(),
-		Type:      reflect.Indirect(reflect.ValueOf(msg)).Type().Name(),
+		Type:      events.TypeOf(msg),
 	}, nil
 }
 
diff --git a/pkg/fnenv/workflows/workflows.go b/pkg/fnenv/workflows/workflows.go
index 2cb6dd9f..e7917181 100644
--- a/pkg/fnenv/workflows/workflows.go
+++ b/pkg/fnenv/workflows/workflows.go
@@ -16,11 +16,11 @@ import (
 	"time"
 
 	"github.com/fission/fission-workflows/pkg/api"
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
+	"github.com/fission/fission-workflows/pkg/api/events"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/fnenv"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
-	"github.com/fission/fission-workflows/pkg/types/events"
 	"github.com/fission/fission-workflows/pkg/types/typedvalues"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/fission/fission-workflows/pkg/util/labels"
@@ -34,6 +34,13 @@ const (
 	Name         = "workflows"
 )
 
+// TODO to fsm
+var terminationEvent = []string{
+	events.TypeOf(&events.InvocationCompleted{}),
+	events.TypeOf(&events.InvocationCanceled{}),
+	events.TypeOf(&events.InvocationFailed{}),
+}
+
 // Runtime provides an abstraction of the workflow engine itself to use as a Task runtime environment.
 type Runtime struct {
 	api          *api.Invocation
@@ -95,8 +102,7 @@ func (rt *Runtime) InvokeWorkflow(ctx context.Context, spec *types.WorkflowInvoc
 			LabelMatcher: labels.And(
 				labels.In(fes.PubSubLabelAggregateType, aggregates.TypeWorkflowInvocation),
 				labels.In(fes.PubSubLabelAggregateID, wfiID),
-				labels.In(fes.PubSubLabelEventType, events.Invocation_INVOCATION_COMPLETED.String(),
-					events.Invocation_INVOCATION_CANCELED.String(), events.Invocation_INVOCATION_FAILED.String())),
+				labels.In(fes.PubSubLabelEventType, terminationEvent...)),
 		})
 		defer pub.Unsubscribe(sub)
 

From 3cc42444ce20de9b9849904e1aa24ab6cd7326f1 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Tue, 17 Jul 2018 16:33:28 +0200
Subject: [PATCH 07/10] Moved httpconv package to typedvalues

---
 pkg/fnenv/fission/envproxy.go                                   | 2 +-
 pkg/fnenv/fission/runtime.go                                    | 2 +-
 pkg/fnenv/native/builtin/http.go                                | 2 +-
 pkg/{fnenv/common => types/typedvalues}/httpconv/httpconv.go    | 0
 .../common => types/typedvalues}/httpconv/httpconv_test.go      | 0
 5 files changed, 3 insertions(+), 3 deletions(-)
 rename pkg/{fnenv/common => types/typedvalues}/httpconv/httpconv.go (100%)
 rename pkg/{fnenv/common => types/typedvalues}/httpconv/httpconv_test.go (100%)

diff --git a/pkg/fnenv/fission/envproxy.go b/pkg/fnenv/fission/envproxy.go
index 4612c8cf..5aaf7cec 100644
--- a/pkg/fnenv/fission/envproxy.go
+++ b/pkg/fnenv/fission/envproxy.go
@@ -14,8 +14,8 @@ import (
 
 	"github.com/fission/fission"
 	"github.com/fission/fission-workflows/pkg/apiserver"
-	"github.com/fission/fission-workflows/pkg/fnenv/common/httpconv"
 	"github.com/fission/fission-workflows/pkg/types"
+	"github.com/fission/fission-workflows/pkg/types/typedvalues/httpconv"
 	"github.com/fission/fission/router"
 	"github.com/golang/protobuf/jsonpb"
 	"github.com/sirupsen/logrus"
diff --git a/pkg/fnenv/fission/runtime.go b/pkg/fnenv/fission/runtime.go
index 14135e93..de5cb5b1 100644
--- a/pkg/fnenv/fission/runtime.go
+++ b/pkg/fnenv/fission/runtime.go
@@ -7,7 +7,7 @@ import (
 	"time"
 
 	"github.com/fission/fission-workflows/pkg/fnenv"
-	"github.com/fission/fission-workflows/pkg/fnenv/common/httpconv"
+	"github.com/fission/fission-workflows/pkg/types/typedvalues/httpconv"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/sirupsen/logrus"
 
diff --git a/pkg/fnenv/native/builtin/http.go b/pkg/fnenv/native/builtin/http.go
index 3638d4c8..753b9e49 100644
--- a/pkg/fnenv/native/builtin/http.go
+++ b/pkg/fnenv/native/builtin/http.go
@@ -9,9 +9,9 @@ import (
 	"net/http"
 	"strings"
 
-	"github.com/fission/fission-workflows/pkg/fnenv/common/httpconv"
 	"github.com/fission/fission-workflows/pkg/types"
 	"github.com/fission/fission-workflows/pkg/types/typedvalues"
+	"github.com/fission/fission-workflows/pkg/types/typedvalues/httpconv"
 	"github.com/sirupsen/logrus"
 )
 
diff --git a/pkg/fnenv/common/httpconv/httpconv.go b/pkg/types/typedvalues/httpconv/httpconv.go
similarity index 100%
rename from pkg/fnenv/common/httpconv/httpconv.go
rename to pkg/types/typedvalues/httpconv/httpconv.go
diff --git a/pkg/fnenv/common/httpconv/httpconv_test.go b/pkg/types/typedvalues/httpconv/httpconv_test.go
similarity index 100%
rename from pkg/fnenv/common/httpconv/httpconv_test.go
rename to pkg/types/typedvalues/httpconv/httpconv_test.go

From 6b5432353b1e02ece1da1aa089c9bf12fb02cf74 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Tue, 17 Jul 2018 16:38:14 +0200
Subject: [PATCH 08/10] Improved documentation in httpconv package

---
 pkg/api/events/events.proto                |  2 +-
 pkg/types/typedvalues/httpconv/httpconv.go | 15 ++++++++++++---
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/pkg/api/events/events.proto b/pkg/api/events/events.proto
index 5ceac3fe..9bbdb82e 100644
--- a/pkg/api/events/events.proto
+++ b/pkg/api/events/events.proto
@@ -3,7 +3,7 @@ syntax = "proto3";
 package fission.workflows.events;
 option go_package = "events";
 
-import "pkg/types/types.proto";
+import "github.com/fission/fission-workflows/pkg/types/types.proto";
 
 message EventWrapper {
     string any = 1;
diff --git a/pkg/types/typedvalues/httpconv/httpconv.go b/pkg/types/typedvalues/httpconv/httpconv.go
index f78e5d9a..35c30984 100644
--- a/pkg/types/typedvalues/httpconv/httpconv.go
+++ b/pkg/types/typedvalues/httpconv/httpconv.go
@@ -1,3 +1,4 @@
+// package httpconv provides methods for mapping typedvalues to HTTP requests and HTTP responses to typedvalues.
 package httpconv
 
 import (
@@ -30,7 +31,7 @@ const (
 	methodDefault       = http.MethodPost
 )
 
-// ParseRequest maps a HTTP request to a target map.
+// ParseRequest maps a HTTP request to a target map of typedvalues.
 func ParseRequest(r *http.Request) (map[string]*types.TypedValue, error) {
 	target := map[string]*types.TypedValue{}
 	// Content-Type is a common problem, so log this for every request
@@ -63,6 +64,7 @@ func ParseRequest(r *http.Request) (map[string]*types.TypedValue, error) {
 	return target, nil
 }
 
+// ParseRequest maps the body of the HTTP request to a corresponding typedvalue.
 func ParseBody(data io.Reader, contentType string) (types.TypedValue, error) {
 	if len(contentType) == 0 {
 		contentType = contentTypeDefault
@@ -139,7 +141,11 @@ func ParseQuery(r *http.Request) types.TypedValue {
 	return *tv
 }
 
+//
 // formatting logic
+//
+
+// FormatResponse maps an TypedValue to an HTTP response
 func FormatResponse(w http.ResponseWriter, output *types.TypedValue, outputErr *types.Error) {
 	if w == nil {
 		panic("cannot format response to nil")
@@ -170,6 +176,7 @@ func FormatResponse(w http.ResponseWriter, output *types.TypedValue, outputErr *
 	return
 }
 
+// FormatRequest maps a map of typed values to an HTTP request
 func FormatRequest(source map[string]*types.TypedValue, target *http.Request) error {
 	if target == nil {
 		panic("cannot format request to nil")
@@ -233,7 +240,7 @@ func FormatMethod(inputs map[string]*types.TypedValue) string {
 	return methodDefault
 }
 
-// TODO support multivalued query params at some point
+// FUTURE: support multivalued query params
 func FormatQuery(inputs map[string]*types.TypedValue) url.Values {
 	queryInput := inputs[types.InputQuery]
 	if queryInput == nil {
@@ -358,7 +365,7 @@ func DetermineContentTypeInputs(inputs map[string]*types.TypedValue) string {
 	}
 }
 
-// TODO support multi-headers at some point
+// FUTURE: support multi-headers at some point
 func FormatHeaders(inputs map[string]*types.TypedValue) http.Header {
 	headers := http.Header{}
 	rawHeaders, ok := inputs[types.InputHeaders]
@@ -384,7 +391,9 @@ func FormatHeaders(inputs map[string]*types.TypedValue) http.Header {
 	return headers
 }
 
+//
 // Util
+//
 
 func flattenMultimap(mm map[string][]string) map[string]interface{} {
 	target := map[string]interface{}{}

From 2a4d87e6dc75fdbd3f99a538e571eee202124a13 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Tue, 17 Jul 2018 18:23:08 +0200
Subject: [PATCH 09/10] Regenerated grpc sources

---
 pkg/api/events/events.pb.go | 61 +++++++++++++++++++------------------
 1 file changed, 31 insertions(+), 30 deletions(-)

diff --git a/pkg/api/events/events.pb.go b/pkg/api/events/events.pb.go
index 9a253d2e..905b85be 100644
--- a/pkg/api/events/events.pb.go
+++ b/pkg/api/events/events.pb.go
@@ -28,7 +28,7 @@ package events
 import proto "github.com/golang/protobuf/proto"
 import fmt "fmt"
 import math "math"
-import fission_workflows_types "pkg/types"
+import fission_workflows_types "github.com/fission/fission-workflows/pkg/types"
 
 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -273,34 +273,35 @@ func init() {
 func init() { proto.RegisterFile("pkg/api/events/events.proto", fileDescriptor0) }
 
 var fileDescriptor0 = []byte{
-	// 458 bytes of a gzipped FileDescriptorProto
+	// 475 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x94, 0xe1, 0x6b, 0xd4, 0x30,
-	0x18, 0xc6, 0xe9, 0xb6, 0x3b, 0xf4, 0x3d, 0xa7, 0x5b, 0x64, 0x70, 0x4c, 0x94, 0x23, 0x22, 0x0c,
-	0xc4, 0x1e, 0x6e, 0x7e, 0x70, 0xfa, 0x41, 0xdc, 0x3c, 0xd9, 0x44, 0x45, 0x32, 0xd9, 0x44, 0xf0,
-	0x43, 0x6c, 0xde, 0x8d, 0xd2, 0x9a, 0x84, 0x24, 0xbd, 0xd1, 0x7f, 0xcd, 0xbf, 0x4e, 0xd2, 0xe4,
-	0x6c, 0x0f, 0xbd, 0x53, 0xb6, 0x2f, 0x6d, 0x49, 0xdf, 0xe7, 0x97, 0xf7, 0x79, 0xde, 0xb4, 0x70,
-	0x4f, 0x17, 0x17, 0x63, 0xae, 0xf3, 0x31, 0x4e, 0x51, 0x3a, 0x1b, 0x6f, 0xa9, 0x36, 0xca, 0x29,
-	0x32, 0x3c, 0xcf, 0xad, 0xcd, 0x95, 0x4c, 0x2f, 0x95, 0x29, 0xce, 0x4b, 0x75, 0x69, 0xd3, 0xf0,
-	0x7e, 0x7b, 0xcb, 0xcb, 0x5c, 0xad, 0xd1, 0x86, 0x6b, 0x10, 0xd0, 0x11, 0xdc, 0x9a, 0xf8, 0x82,
-	0x33, 0xc3, 0xb5, 0x46, 0x43, 0x36, 0x60, 0x95, 0xcb, 0x7a, 0x98, 0x8c, 0x92, 0x9d, 0x9b, 0xcc,
-	0x3f, 0xd2, 0xf7, 0x70, 0xe7, 0x2c, 0xc2, 0x0e, 0x0d, 0x72, 0x87, 0x82, 0xec, 0xc3, 0x9a, 0xd5,
-	0x98, 0x35, 0x55, 0x83, 0xdd, 0x47, 0xe9, 0x9f, 0x9b, 0x86, 0x2d, 0x66, 0xba, 0x13, 0x8d, 0x19,
-	0x6b, 0x24, 0x74, 0xb3, 0xa5, 0xbd, 0xc1, 0x12, 0x1d, 0x0a, 0xfa, 0x33, 0x81, 0xdb, 0xb3, 0xb5,
-	0x4f, 0xdc, 0x58, 0x14, 0xe4, 0x18, 0x7a, 0x8e, 0xdb, 0xc2, 0x0e, 0x93, 0xd1, 0xea, 0xce, 0x60,
-	0x77, 0x2f, 0x5d, 0x64, 0x2b, 0x9d, 0x17, 0xa6, 0x9f, 0xbd, 0x6a, 0x22, 0x9d, 0xa9, 0x59, 0x20,
-	0x6c, 0x7f, 0x03, 0x68, 0x17, 0xbd, 0xbd, 0x02, 0x7f, 0xdb, 0x2b, 0xb0, 0x26, 0xfb, 0xd0, 0x9b,
-	0xf2, 0xb2, 0xc2, 0xe1, 0x4a, 0x63, 0xe6, 0xe1, 0x42, 0x33, 0x9e, 0x72, 0xe2, 0xb8, 0xab, 0x2c,
-	0x0b, 0x8a, 0x17, 0x2b, 0xcf, 0x13, 0xfa, 0x01, 0xb6, 0xba, 0x2d, 0xe4, 0xf2, 0xe2, 0x2d, 0xcf,
-	0x4b, 0x14, 0xe4, 0x19, 0xf4, 0xd0, 0x18, 0x65, 0x62, 0x48, 0x0f, 0x16, 0x72, 0x27, 0xbe, 0x8a,
-	0x85, 0x62, 0xfa, 0x05, 0x36, 0x8f, 0xe5, 0x54, 0x65, 0xdc, 0xe5, 0x4a, 0xce, 0xe2, 0x3e, 0x9c,
-	0x8b, 0x7b, 0xfc, 0xcf, 0xb8, 0x5b, 0x42, 0x27, 0x78, 0x06, 0x77, 0x3b, 0x64, 0xf5, 0x43, 0x37,
-	0xe1, 0x93, 0x97, 0xd0, 0x57, 0x95, 0xd3, 0x95, 0x8b, 0xf4, 0x25, 0xfe, 0x6b, 0x8d, 0xe2, 0xd4,
-	0x1b, 0x67, 0x51, 0x42, 0xdf, 0x01, 0xe9, 0x30, 0xb9, 0xcc, 0xf0, 0xea, 0xce, 0x8f, 0xba, 0xfd,
-	0xf9, 0xac, 0x5f, 0x0b, 0x81, 0x82, 0x3c, 0x85, 0x35, 0x3f, 0xc7, 0xc8, 0xba, 0xbf, 0x74, 0x3a,
-	0xac, 0x29, 0xa5, 0x47, 0xb0, 0xd1, 0x92, 0xae, 0x35, 0x8d, 0x8f, 0x30, 0x88, 0x53, 0x37, 0x3e,
-	0xab, 0x57, 0x73, 0x73, 0x78, 0xbc, 0xb4, 0x97, 0xbf, 0xce, 0xe0, 0x14, 0xd6, 0x1b, 0x5e, 0x95,
-	0x65, 0x88, 0xde, 0xdd, 0x04, 0xfa, 0x06, 0x6d, 0x55, 0xce, 0xd2, 0x7f, 0xf2, 0xbf, 0xcc, 0x70,
-	0x0e, 0xa3, 0x98, 0xae, 0xc7, 0x3e, 0x8b, 0x5c, 0x6b, 0x14, 0xf4, 0x20, 0x1c, 0xf9, 0xeb, 0x58,
-	0x3f, 0xb8, 0xf1, 0xb5, 0x1f, 0xbe, 0xb0, 0xef, 0xfd, 0xe6, 0x47, 0xb1, 0xf7, 0x2b, 0x00, 0x00,
-	0xff, 0xff, 0x8b, 0x11, 0x02, 0x03, 0x78, 0x04, 0x00, 0x00,
+	0x18, 0xc6, 0xe9, 0xb6, 0x3b, 0xf4, 0x3d, 0xa7, 0x5b, 0x44, 0x38, 0x26, 0xca, 0x11, 0x11, 0x06,
+	0xb2, 0x16, 0x37, 0x3f, 0xb8, 0xf9, 0x41, 0xdc, 0x3c, 0xd9, 0x44, 0x45, 0x3a, 0xd9, 0x44, 0xf0,
+	0x43, 0xd6, 0xbc, 0x3b, 0x4b, 0xbb, 0x26, 0x24, 0xe9, 0x8d, 0xfe, 0x6b, 0xfe, 0x75, 0x92, 0x26,
+	0x5d, 0x7b, 0xe8, 0x9d, 0xe2, 0x7d, 0x69, 0x4a, 0xfa, 0x3e, 0xbf, 0xbe, 0xcf, 0xf3, 0xa6, 0x85,
+	0x87, 0x32, 0x9b, 0x44, 0x4c, 0xa6, 0x11, 0x4e, 0xb1, 0x30, 0xda, 0x2f, 0xa1, 0x54, 0xc2, 0x08,
+	0x32, 0xbc, 0x4c, 0xb5, 0x4e, 0x45, 0x11, 0x5e, 0x0b, 0x95, 0x5d, 0xe6, 0xe2, 0x5a, 0x87, 0xee,
+	0xf9, 0xd6, 0xc1, 0x24, 0x35, 0x3f, 0xca, 0x8b, 0x30, 0x11, 0x57, 0x91, 0x2f, 0x6a, 0xd6, 0x9d,
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+	0xb9, 0x62, 0x52, 0xa2, 0x22, 0x1b, 0xb0, 0xca, 0x8a, 0x6a, 0x18, 0x8c, 0x82, 0xed, 0xdb, 0xb1,
+	0xbd, 0xa5, 0x1f, 0xe0, 0xde, 0xb9, 0x87, 0x1c, 0x29, 0x64, 0x06, 0x39, 0xd9, 0x87, 0x35, 0x2d,
+	0x31, 0xa9, 0xab, 0x06, 0xbb, 0x4f, 0xc3, 0xdf, 0x3b, 0x73, 0xaf, 0x68, 0x74, 0xa7, 0x12, 0x93,
+	0xb8, 0x96, 0xd0, 0xcd, 0x96, 0xf6, 0x16, 0x73, 0x34, 0xc8, 0xe9, 0xcf, 0x00, 0xee, 0x36, 0x7b,
+	0x9f, 0x99, 0xd2, 0xc8, 0xc9, 0x09, 0xf4, 0x0c, 0xd3, 0x99, 0x1e, 0x06, 0xa3, 0xd5, 0xed, 0xc1,
+	0xee, 0x5e, 0x38, 0xcf, 0x7b, 0x38, 0x2b, 0x0c, 0xbf, 0x58, 0xd5, 0xb8, 0x30, 0xaa, 0x8a, 0x1d,
+	0x61, 0xeb, 0x3b, 0x40, 0xbb, 0x69, 0xed, 0x65, 0x78, 0x63, 0x2f, 0xc3, 0x8a, 0xec, 0x43, 0x6f,
+	0xca, 0xf2, 0x12, 0x87, 0x2b, 0xb5, 0x99, 0x27, 0x73, 0xcd, 0x58, 0xca, 0xa9, 0x61, 0xa6, 0xd4,
+	0xb1, 0x53, 0x1c, 0xac, 0xbc, 0x0c, 0xe8, 0x47, 0x78, 0xd0, 0x6d, 0x21, 0x2d, 0x26, 0xef, 0x58,
+	0x9a, 0x23, 0x27, 0x2f, 0xa0, 0x87, 0x4a, 0x09, 0xe5, 0x43, 0x7a, 0x3c, 0x97, 0x3b, 0xb6, 0x55,
+	0xb1, 0x2b, 0xa6, 0x5f, 0x61, 0xf3, 0xa4, 0x98, 0x8a, 0x84, 0x99, 0x54, 0x14, 0x4d, 0xdc, 0x47,
+	0x33, 0x71, 0x47, 0x7f, 0x8d, 0xbb, 0x25, 0x74, 0x82, 0x8f, 0xe1, 0x7e, 0x87, 0x2c, 0xae, 0x64,
+	0x1d, 0x3e, 0x79, 0x05, 0x7d, 0x51, 0x1a, 0x59, 0x1a, 0x4f, 0x5f, 0xe0, 0xbf, 0x92, 0xc8, 0xcf,
+	0xac, 0xf1, 0xd8, 0x4b, 0xe8, 0x7b, 0x20, 0x1d, 0x26, 0x2b, 0x12, 0xfc, 0x7f, 0xe7, 0xc7, 0xdd,
+	0xfe, 0x6c, 0xd6, 0x6f, 0x38, 0x47, 0x4e, 0x9e, 0xc3, 0x9a, 0x9d, 0xa3, 0x67, 0x3d, 0x5a, 0x38,
+	0x9d, 0xb8, 0x2e, 0xa5, 0xc7, 0xb0, 0xd1, 0x92, 0x96, 0x9a, 0xc6, 0x27, 0x18, 0xf8, 0xa9, 0x2b,
+	0x9b, 0xd5, 0xeb, 0x99, 0x39, 0x3c, 0x5b, 0xd8, 0xcb, 0x1f, 0x67, 0x70, 0x06, 0xeb, 0x35, 0xaf,
+	0x4c, 0x12, 0x44, 0xeb, 0x6e, 0x0c, 0x7d, 0x85, 0xba, 0xcc, 0x9b, 0xf4, 0x77, 0xfe, 0x95, 0xe9,
+	0xce, 0xa1, 0x17, 0xd3, 0x75, 0xdf, 0x67, 0x96, 0x4a, 0x89, 0x9c, 0x1e, 0xba, 0x23, 0xbf, 0x8c,
+	0xf5, 0xc3, 0x5b, 0xdf, 0xfa, 0xee, 0x0b, 0xbb, 0xe8, 0xd7, 0x3f, 0x8a, 0xbd, 0x5f, 0x01, 0x00,
+	0x00, 0xff, 0xff, 0xf6, 0x42, 0x8f, 0x08, 0x9d, 0x04, 0x00, 0x00,
 }

From b7b4a3e4fae339653a8a8e433fd08a4fd3f28328 Mon Sep 17 00:00:00 2001
From: erwinvaneyk <erwinvaneyk@gmail.com>
Date: Wed, 25 Jul 2018 14:59:27 +0200
Subject: [PATCH 10/10] Added tests for failing and invalid invocations

---
 pkg/api/aggregates/invocation.go       |  4 +-
 pkg/api/aggregates/task.go             |  4 +-
 pkg/api/aggregates/workflow.go         |  4 +-
 pkg/api/invocation.go                  |  2 +-
 pkg/api/task.go                        |  2 +-
 pkg/fnenv/workflows/workflows_test.go  |  4 +-
 test/integration/bundle/bundle_test.go | 54 ++++++++++++++++++++++++--
 7 files changed, 61 insertions(+), 13 deletions(-)

diff --git a/pkg/api/aggregates/invocation.go b/pkg/api/aggregates/invocation.go
index 94297c34..bcefcc6e 100644
--- a/pkg/api/aggregates/invocation.go
+++ b/pkg/api/aggregates/invocation.go
@@ -91,8 +91,8 @@ func (wi *WorkflowInvocation) ApplyEvent(event *fes.Event) error {
 		wi.Status.Status = types.WorkflowInvocationStatus_FAILED
 	default:
 		log.WithFields(log.Fields{
-			"event": event,
-		}).Warn("Skipping unimplemented event.")
+			"aggregate": wi.Aggregate(),
+		}).Warnf("Skipping unimplemented event: %T", eventData)
 	}
 	return err
 }
diff --git a/pkg/api/aggregates/task.go b/pkg/api/aggregates/task.go
index 8607bbc7..4075e789 100644
--- a/pkg/api/aggregates/task.go
+++ b/pkg/api/aggregates/task.go
@@ -68,8 +68,8 @@ func (ti *TaskInvocation) ApplyEvent(event *fes.Event) error {
 		ti.Status.UpdatedAt = event.Timestamp
 	default:
 		log.WithFields(log.Fields{
-			"event": event,
-		}).Warn("Skipping unimplemented event.")
+			"aggregate": ti.Aggregate(),
+		}).Warnf("Skipping unimplemented event: %T", eventData)
 	}
 	return nil
 }
diff --git a/pkg/api/aggregates/workflow.go b/pkg/api/aggregates/workflow.go
index 0762b1c8..f8ba90c8 100644
--- a/pkg/api/aggregates/workflow.go
+++ b/pkg/api/aggregates/workflow.go
@@ -68,8 +68,8 @@ func (wf *Workflow) ApplyEvent(event *fes.Event) error {
 		wf.Status.Status = types.WorkflowStatus_DELETED
 	default:
 		log.WithFields(log.Fields{
-			"event": event,
-		}).Warn("Skipping unimplemented event.")
+			"aggregate": wf.Aggregate(),
+		}).Warnf("Skipping unimplemented event: %T", eventData)
 	}
 	return nil
 }
diff --git a/pkg/api/invocation.go b/pkg/api/invocation.go
index bda22339..993a1c8b 100644
--- a/pkg/api/invocation.go
+++ b/pkg/api/invocation.go
@@ -101,7 +101,7 @@ func (ia *Invocation) Fail(invocationID string, errMsg error) error {
 	}
 
 	var msg string
-	if errMsg == nil {
+	if errMsg != nil {
 		msg = errMsg.Error()
 	}
 	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(invocationID), &events.InvocationFailed{
diff --git a/pkg/api/task.go b/pkg/api/task.go
index a99e4428..67e986b1 100644
--- a/pkg/api/task.go
+++ b/pkg/api/task.go
@@ -123,7 +123,7 @@ func (ap *Task) Fail(invocationID string, taskID string, errMsg string) error {
 		return validate.NewError("taskID", errors.New("id should not be empty"))
 	}
 
-	event, err := fes.NewEvent(*aggregates.NewWorkflowInvocationAggregate(invocationID), &events.TaskFailed{
+	event, err := fes.NewEvent(*aggregates.NewTaskInvocationAggregate(taskID), &events.TaskFailed{
 		Error: &types.Error{Message: errMsg},
 	})
 	if err != nil {
diff --git a/pkg/fnenv/workflows/workflows_test.go b/pkg/fnenv/workflows/workflows_test.go
index d101b872..c1e731a5 100644
--- a/pkg/fnenv/workflows/workflows_test.go
+++ b/pkg/fnenv/workflows/workflows_test.go
@@ -8,10 +8,10 @@ import (
 	"time"
 
 	"github.com/fission/fission-workflows/pkg/api"
+	"github.com/fission/fission-workflows/pkg/api/aggregates"
 	"github.com/fission/fission-workflows/pkg/fes"
 	"github.com/fission/fission-workflows/pkg/fes/backend/mem"
 	"github.com/fission/fission-workflows/pkg/types"
-	"github.com/fission/fission-workflows/pkg/types/aggregates"
 	"github.com/fission/fission-workflows/pkg/types/typedvalues"
 	"github.com/fission/fission-workflows/pkg/types/validate"
 	"github.com/stretchr/testify/assert"
@@ -154,7 +154,7 @@ func TestRuntime_Invoke(t *testing.T) {
 func setup() (*Runtime, *api.Invocation, *mem.Backend, fes.CacheReaderWriter) {
 	backend := mem.NewBackend()
 	invocationAPI := api.NewInvocationAPI(backend)
-	cache := fes.NewSubscribedCache(context.Background(), fes.NewMapCache(), func() fes.Aggregator {
+	cache := fes.NewSubscribedCache(context.Background(), fes.NewMapCache(), func() fes.Entity {
 		return aggregates.NewWorkflowInvocation("")
 	}, backend.Subscribe())
 	runtime := NewRuntime(invocationAPI, cache)
diff --git a/test/integration/bundle/bundle_test.go b/test/integration/bundle/bundle_test.go
index 4ffe4e2d..46f91437 100644
--- a/test/integration/bundle/bundle_test.go
+++ b/test/integration/bundle/bundle_test.go
@@ -160,7 +160,6 @@ func TestDynamicWorkflowInvocation(t *testing.T) {
 	defer cancelFn()
 	cl, wi := setup()
 
-	// Test workflow creation
 	wfSpec := &types.WorkflowSpec{
 		ApiVersion: types.WorkflowAPIVersion,
 		OutputTask: "fakeFinalTask",
@@ -232,7 +231,6 @@ func TestInlineWorkflowInvocation(t *testing.T) {
 	defer cancelFn()
 	cl, wi := setup()
 
-	// Test workflow creation
 	wfSpec := &types.WorkflowSpec{
 		ApiVersion: types.WorkflowAPIVersion,
 		OutputTask: "finalTask",
@@ -298,7 +296,6 @@ func TestLongRunningWorkflowInvocation(t *testing.T) {
 	defer cancelFn()
 	cl, wi := setup()
 
-	// Test workflow creation
 	wfSpec := &types.WorkflowSpec{
 		ApiVersion: types.WorkflowAPIVersion,
 		OutputTask: "final",
@@ -408,6 +405,57 @@ func TestWorkflowCancellation(t *testing.T) {
 	assert.Equal(t, api.ErrInvocationCanceled, wfi.GetStatus().GetError().Error())
 }
 
+func TestInvocationInvalid(t *testing.T) {
+	ctx, cancelFn := context.WithTimeout(context.Background(), TestTimeout)
+	defer cancelFn()
+	cl, _ := setup()
+
+	wfSpec := &types.WorkflowSpec{
+		ApiVersion: types.WorkflowAPIVersion,
+		OutputTask: "nonexistentTask",
+		Tasks: types.Tasks{
+			"task1": {
+				FunctionRef: builtin.Noop,
+			},
+		},
+	}
+	_, err := cl.Create(ctx, wfSpec)
+	assert.Error(t, err)
+}
+
+func TestInvocationFailed(t *testing.T) {
+	ctx, cancelFn := context.WithTimeout(context.Background(), TestTimeout)
+	defer cancelFn()
+	cl, wi := setup()
+
+	msg := "expected error"
+	wfSpec := &types.WorkflowSpec{
+		ApiVersion: types.WorkflowAPIVersion,
+		OutputTask: "task1",
+		Tasks: types.Tasks{
+			"task1": {
+				FunctionRef: builtin.Fail,
+				Inputs:      typedvalues.Input(msg),
+			},
+		},
+	}
+	wfResp, err := cl.Create(ctx, wfSpec)
+	defer cl.Delete(ctx, wfResp)
+	assert.NoError(t, err, err)
+	assert.NotNil(t, wfResp)
+	assert.NotEmpty(t, wfResp.Id)
+
+	wiSpec := types.NewWorkflowInvocationSpec(wfResp.Id)
+	wfi, err := wi.InvokeSync(ctx, wiSpec)
+	assert.NoError(t, err)
+	assert.Empty(t, wfi.Status.DynamicTasks)
+	assert.True(t, wfi.Status.Finished())
+	assert.False(t, wfi.Status.Successful())
+	assert.Equal(t, len(wfSpec.Tasks), len(wfi.Status.Tasks))
+	// assert.Equal(t, msg, wfi.GetStatus().GetError().GetMessage())
+	// TODO generate consistent error report!
+}
+
 func setup() (apiserver.WorkflowAPIClient, apiserver.WorkflowInvocationAPIClient) {
 	conn, err := grpc.Dial(gRPCAddress, grpc.WithInsecure())
 	if err != nil {