frontend-plugin-api: allow extensions to only define a name

Co-authored-by: Camila Belo <camilaibs@gmail.com>
Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

packages/frontend-plugin-api/src/wiring/resolveExtensionDefinition.test.ts

@@ -20,6 +20,7 @@ import { resolveExtensionDefinition } from './resolveExtensionDefinition';
 describe('resolveExtensionDefinition', () => {
   it.each([
     [{ namespace: 'ns' }, 'ns'],
+    [{ namespace: 'n' }, 'n'],
     [{ namespace: 'ns', name: 'n' }, 'ns/n'],
     [{ kind: 'k', namespace: 'ns' }, 'k:ns'],
     [{ kind: 'k', namespace: 'ns', name: 'n' }, 'k:ns/n'],
@@ -34,15 +35,14 @@ describe('resolveExtensionDefinition', () => {
     expect(() =>
       resolveExtensionDefinition({
         kind: 'k',
-        name: 'n',
       } as ExtensionDefinition<unknown>),
     ).toThrow(
-      'Extension must declare an explicit namespace as it could not be resolved from context, name=n kind=k',
+      'Extension must declare an explicit namespace or name as it could not be resolved from context, kind=k namespace=undefined name=undefined',
     );
     expect(() =>
       resolveExtensionDefinition({} as ExtensionDefinition<unknown>),
     ).toThrow(
-      'Extension must declare an explicit namespace as it could not be resolved from context, name=undefined kind=undefined',
+      'Extension must declare an explicit namespace or name as it could not be resolved from context, kind=undefined namespace=undefined name=undefined',
     );
   });
 });

packages/frontend-plugin-api/src/wiring/resolveExtensionDefinition.ts

@@ -24,22 +24,17 @@ export function resolveExtensionDefinition<TConfig>(
   const { name, kind, namespace: _, ...rest } = definition;
   const namespace = context?.namespace ?? definition.namespace;
 
-  if (!namespace) {
+  const namePart =
+    name && namespace ? `${namespace}/${name}` : namespace || name;
+  if (!namePart) {
     throw new Error(
-      `Extension must declare an explicit namespace as it could not be resolved from context, name=${name} kind=${kind}`,
+      `Extension must declare an explicit namespace or name as it could not be resolved from context, kind=${kind} namespace=${namespace} name=${name}`,
     );
   }
 
-  let id;
-  if (kind && name) {
-    id = `${kind}:${namespace}/${name}`; // nav-item:catalog/index
-  } else if (kind) {
-    id = `${kind}:${namespace}`; // nav-item:search
-  } else if (name) {
-    id = `${namespace}/${name}`; // core/nav
-  } else {
-    id = namespace; // core
-  }
-
-  return { id, ...rest, $$type: '@backstage/Extension' };
+  return {
+    ...rest,
+    id: kind ? `${kind}:${namePart}` : namePart,
+    $$type: '@backstage/Extension',
+  };
 }

packages/frontend-test-utils/src/app/createExtensionTester.ts

@@ -49,7 +49,7 @@ export class ExtensionTester {
   ): ExtensionTester {
     const withNamespace = {
       ...extension,
-      namespace: extension.namespace ?? 'test',
+      name: !extension.namespace && !extension.name ? 'test' : extension.name,
     };
     this.#extensions.push({
       id: resolveExtensionDefinition(withNamespace).id,