Extend application's capabilities by trait definition

apis/core.oam.dev/v1alpha2/core_types.go

@@ -97,7 +97,7 @@ type WorkloadDefinitionList struct {
 // A TraitDefinitionSpec defines the desired state of a TraitDefinition.
 type TraitDefinitionSpec struct {
 	// Reference to the CustomResourceDefinition that defines this trait kind.
-	Reference DefinitionReference `json:"definitionRef"`
+	Reference DefinitionReference `json:"definitionRef,omitempty"`
 
 	// Revision indicates whether a trait is aware of component revision
 	// +optional

charts/vela-core/crds/core.oam.dev_traitdefinitions.yaml

@@ -66,8 +66,6 @@ spec:
               workloadRefPath:
                 description: WorkloadRefPath indicates where/if a trait accepts a workloadRef object
                 type: string
-            required:
-            - definitionRef
             type: object
         type: object
     served: true

config/samples/vela-server/Demo.md

@@ -0,0 +1,144 @@
+# Application Example
+
+In this Demo, Application application-sample will be converted to appconfig and component
+
+The fields in the application spec come from the parametes defined in the definition template
+, so we must install Definition at first
+
+Step 1: Install Workload Definition & Trait Definition
+```
+kubectl apply -f template.yaml
+```
+Step 2: Create a sample application in the cluster
+```
+kubectl apply -f application-sample.yaml
+```
+Step 3: View the application status
+```
+kubectl get -f application-sample.yaml -oyaml
+
+// You can see the following
+apiVersion: core.oam.dev/v1alpha2
+kind: Application
+metadata:
+  annotations:
+    kubectl.kubernetes.io/last-applied-configuration: |
+      {"apiVersion":"core.oam.dev/v1alpha2","kind":"Application","metadata":{"annotations":{},"name":"application-sample","namespace":"oam-test"},"spec":{"template":"services:\n  myweb:\n    type: worker\n    image: \"busybox\"\n    cmd:\n    - sleep\n    - \"1000\"\n    scaler:\n      replicas: 10"}}
+  name: application-sample
+  namespace: oam-test
+spec:
+  services:
+    myweb:
+      cmd:
+      - sleep
+      - "1000"
+      image: busybox
+      scaler:
+        replicas: 10
+      service:
+        http:
+          server: 80
+      sidecar:
+        command:
+        - sleep
+        - "1000"
+        image: busybox
+        name: test-sidecar
+      type: worker
+status:
+  conditions:
+  - lastTransitionTime: "2020-12-02T12:12:52Z"
+    reason: Available
+    status: "True"
+    type: Parsed
+  - lastTransitionTime: "2020-12-02T12:12:52Z"
+    reason: Available
+    status: "True"
+    type: Built
+  - lastTransitionTime: "2020-12-02T12:12:52Z"
+    reason: Available
+    status: "True"
+    type: Applied
+  status: running
+
+```
+
+Step 4: View the oam CR generated by application
+
+```
+kubectl get appconfig/application-sample -oyaml
+
+// appconfig is as follows
+apiVersion: core.oam.dev/v1alpha2
+kind: ApplicationConfiguration
+metadata:
+  labels:
+    application.oam.dev: application-sample
+  name: application-sample
+  namespace: oam-test
+  ownerReferences:
+  - apiVersion: core.oam.dev/v1alpha2
+    controller: true
+    kind: Application
+    name: application-sample
+    uid: dca7acc3-664c-422b-aa52-4fe012e37974
+spec:  
+  components:
+  - componentName: myweb
+    traits:
+    - trait:
+        apiVersion: v1
+        kind: Service
+        metadata:
+          name: myweb
+        spec:
+          ports:
+          - port: 80
+            targetPort: 80
+          selector:
+            app: myweb
+
+kubectl get component/myweb -oyaml
+
+// component is as follows
+apiVersion: core.oam.dev/v1alpha2
+kind: Component
+metadata:
+  labels:
+    application.oam.dev: application-sample
+  name: myweb
+  namespace: oam-test
+  ownerReferences:
+  - apiVersion: core.oam.dev/v1alpha2
+    controller: true
+    kind: Application
+    name: application-sample
+    uid: dca7acc3-664c-422b-aa52-4fe012e37974
+spec:
+  workload:
+    apiVersion: apps/v1
+    kind: Deployment
+    spec:
+      replicas: 10
+      selector:
+        matchLabels:
+          app.oam.dev/component: myweb
+      template:
+        metadata:
+          labels:
+            app: myweb
+            app.oam.dev/component: myweb
+        spec:
+          containers:
+          - command:
+            - sleep
+            - "1000"
+            image: busybox
+            name: myweb
+          - command:
+            - sleep
+            - "1000"
+            image: busybox
+            name: test-sidecar     
+```
+