feat(catalog): add field to the component entity to specify implemented apis per component

docs/features/software-catalog/descriptor-format.md

@@ -254,6 +254,8 @@ spec:
   type: website
   lifecycle: production
   owner: artist-relations@example.com
+  implementsApis:
+    - artist-api
 ```
 
 In addition to the [common envelope metadata](#common-to-all-kinds-the-metadata)
@@ -314,6 +316,14 @@ Apart from being a string, the software catalog leaves the format of this field
 open to implementers to choose. Most commonly, it is set to the ID or email of a
 group of people in an organizational structure.
 
+### `spec.implementsApis` [optional]
+
+Links APIs that are implemented by the component, e.g. `artist-api`. This field
+is optional.
+
+The software catalog expects a list of one or more strings that references the
+names of other entities of the `kind` `API`.
+
 ## Kind: Template
 
 Describes the following entity kind:

packages/catalog-model/examples/petstore-component.yaml

@@ -0,0 +1,13 @@
+apiVersion: backstage.io/v1alpha1
+kind: Component
+metadata:
+  name: petstore
+  description: Petstore
+spec:
+  type: service
+  lifecycle: experimental
+  owner: pets@example.com
+  implementedApis:
+    - petstore
+    - streetlights
+    - hello-world

packages/catalog-model/src/kinds/ComponentEntityV1alpha1.test.ts

@@ -35,6 +35,7 @@ describe('ComponentV1alpha1Policy', () => {
         type: 'service',
         lifecycle: 'production',
         owner: 'me',
+        implementsApis: ['api-0'],
       },
     };
     policy = new ComponentEntityV1alpha1Policy();

packages/catalog-model/src/kinds/ComponentEntityV1alpha1.ts

@@ -28,6 +28,7 @@ export interface ComponentEntityV1alpha1 extends Entity {
     type: string;
     lifecycle: string;
     owner: string;
+    implementsApis?: string[];
   };
 }
 
@@ -43,6 +44,7 @@ export class ComponentEntityV1alpha1Policy implements EntityPolicy {
           type: yup.string().required().min(1),
           lifecycle: yup.string().required().min(1),
           owner: yup.string().required().min(1),
+          implementsApis: yup.array(yup.string()).notRequired(),
         })
         .required(),
     });