Merge pull request #91 from fission/fission-headers-query-support

Add support for inputs specifying task metadata

examples/whales/README.md

@@ -1,29 +1,64 @@
 # Simple Examples
-This directory contains two simple example workflows (and two whales!), along with the required functions.
+This directory contains multiple simple example workflows (and whales!), along with the required functions.
+The intention of each workflow is to show-off and explain a concept in Fission Workflows
 
 ## Setup
 - Make sure that you have a running Fission Cluster with the workflow engine, see the [readme](../../README.md) for details.
 - Deploy both the functions, using the [deploy.sh](./deploy.sh) script, or run the commands listed there manually.
 
-### Example: Echowhale
-The 'echowhale' workflow is a minimal workflow, consisting of whale echoing the input.
+## Examples
+
+
+### Echowhale
+The `echowhale` workflow is a minimal workflow, consisting of whale echoing the input.
 The main feature it shows is that a workflow from the user's view the same as a Fission function.
 
-To invoke:
+Run:
 ```bash
-curl -XPOST -d 'Whale you echo?' $FISSION_ROUTER/fission-function/echowhale
+curl -XPOST -d 'Whale you echo?' ${FISSION_ROUTER}/fission-function/echowhale
 ```
 
-### Example: Fortunewhale
-The fortunewhale workflow consists of multiple steps, generating a 'fortune' and passing it through the whalesay function that was used in the first workflow.
+### Fortunewhale
+The `fortunewhale` workflow consists of multiple steps, generating a 'fortune' and passing it through the whalesay function that was used in the first workflow.
 The features introduced in this example:
 - Dependencies between tasks
 - Mapping a task's output to another task's input
 - The 'noop' internal function, which is a function executed within the engine itself.
 
-To invoke:
+Run:
 ```bash
-curl -XPOST $FISSION_ROUTER/fission-function/fortunewhale
+curl -XPOST ${FISSION_ROUTER}/fission-function/fortunewhale
+```
+
+### Maybewhale
+The `maybewhale` workflow consists of a simple if-else condition.
+Depending on the length of the input, the workflow transforms the input.
+If the input is smaller than 20 characters, the workflow will run the `whalesay` task.
+If not, it will simply propagate the user input.
+
+Run:
+```bash
+# This will wrap the input in a whale, because the input is < 20
+curl -XPOST -d 'Whale you echo?' ${FISSION_ROUTER}/fission-function/maybewhale
+
+# This will simply echo the input, because the input is >= 20.
+curl -XPOST -d 'Whale you echo this way too long message?' ${FISSION_ROUTER}/fission-function/maybewhale
 ```
 
-### Example: 
+### Metadatawhale
+The `metadatawhale` workflow shows how to add metadata (headers, query values) to tasks.
+
+Run:
+```bash
+curl -XPOST ${FISSION_ROUTER}/fission-function/metadatawhale
+```
+
+### Nestedwhale
+The `nestedwhale` workflow is surprisingly... empty.
+The principle that 'workflows are fission functions', allows workflows to call other workflows just like you would call regular Fission Functions.
+In this workflow, we generate a fortune and pass it to the dedicated whale echoing workflow: `echowhale`.
+
+Run
+```bash
+curl -XPOST ${FISSION_ROUTER}/fission-function/nestedwhale
+```

examples/whales/deploy.sh

@@ -1,9 +1,11 @@
 #!/bin/sh
 
+# deploy.sh - deploys all functions and workflows in this directory
+
 set -x
 
 # Deploy functions
-fission env create --name binary --image fission/binary-env:0.3.0
+fission env create --name binary --image fission/binary-env
 fission fn create --name whalesay --env binary --deploy ./whalesay.sh
 fission fn create --name fortune --env binary --deploy ./fortune.sh
 
@@ -12,3 +14,4 @@ fission fn create --name fortunewhale --env workflow --src ./fortunewhale.wf.yam
 fission fn create --name echowhale --env workflow --src ./echowhale.wf.yaml
 fission fn create --name maybewhale --env workflow --src ./maybewhale.wf.yaml
 fission fn create --name nestedwhale --env workflow --src ./nestedwhale.wf.yaml
+fission fn create --name metadatawhale --env workflow --src ./metadatawhale.wf.yaml

examples/whales/echowhale.wf.yaml

@@ -1,3 +1,4 @@
+# This whale shows how to access and reference with workflow parameters
 apiVersion: 1
 output: echowhale
 tasks:

examples/whales/fortune.sh

@@ -1,7 +1,19 @@
 #!/bin/sh
 
+# fortune - generate wise words
+#
+# Output: string (plain text)
+
+# TODO move this to the build step once the binary environment is a v2 environment
 if ! hash fortune 2>/dev/null; then
     apk add fortune > /dev/null
 fi
 
+# Pretty useless, but used to show headers
+prefix=${HTTP_PREFIX}
+
+if [ ! -z "${prefix}" ] ; then
+    printf "${prefix}"
+fi
+
 fortune -s

examples/whales/fortunewhale.wf.yaml

@@ -1,3 +1,4 @@
+# This whale shows of a basic workflow that combines both Fission Functions (fortune, whalesay) and internal functions (noop)
 apiVersion: 1
 output: WhaleWithFortune
 tasks:

examples/whales/maybewhale.wf.yaml

@@ -1,3 +1,4 @@
+# A whale that shows off how a if-condition works in a workflow
 apiVersion: 1
 output: PassAlong
 tasks:

examples/whales/metadatawhale.wf.yaml

@@ -0,0 +1,8 @@
+# A whale that shows off how to add metadata (e.g. headers, query) to your fission function
+apiVersion: 1
+output: PrefixedFortune
+tasks:
+  PrefixedFortune:
+    run: fortune
+    inputs:
+      header_prefix: "Whale says:"

examples/whales/nestedwhale.wf.yaml

@@ -1,3 +1,4 @@
+# This whale shows of how to call other workflows from a workflow (surprise! There is no difference with regular functions)
 apiVersion: 1
 output: WhaleIt
 tasks:

examples/whales/whalesay.sh

@@ -1,5 +1,11 @@
 #!/bin/sh
 
+# whalesay - let a friendly whale say your message instead
+#
+# input: string (plain text)
+# output: string (plain text)
+
+# TODO move this to the build step once the binary environment is a v2 environment
 if ! hash cowsay 2> /dev/null; then
     apk update > /dev/null
     apk add curl perl > /dev/null

pkg/fnenv/fission/envproxy.go

@@ -123,7 +123,7 @@ func (fp *Proxy) handleRequest(w http.ResponseWriter, r *http.Request) {
 	var resp []byte
 	if invocation.Status.Output != nil {
 		resp = invocation.Status.Output.Value
-		w.Header().Add("Content-Type", ToContentType(invocation.Status.Output))
+		w.Header().Add("Content-Type", inferContentType(invocation.Status.Output, defaultContentType))
 	} else {
 		logrus.Infof("Invocation '%v' has no output.", fnId)
 	}