frontend-plugin-api: add resolveExtensionDefinition helper + use for extension overrides

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

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

@@ -14,12 +14,13 @@
  * limitations under the License.
  */
 
-import { Extension } from './createExtension';
+import { Extension, ExtensionDefinition } from './createExtension';
+import { resolveExtensionDefinition } from './resolveExtensionDefinition';
 import { FeatureFlagConfig } from './types';
 
 /** @public */
 export interface ExtensionOverridesOptions {
-  extensions: Extension<unknown>[];
+  extensions: ExtensionDefinition<unknown>[];
   featureFlags?: FeatureFlagConfig[];
 }
 
@@ -42,7 +43,7 @@ export function createExtensionOverrides(
   return {
     $$type: '@backstage/ExtensionOverrides',
     version: 'v1',
-    extensions: options.extensions,
+    extensions: options.extensions.map(def => resolveExtensionDefinition(def)),
     featureFlags: options.featureFlags ?? [],
   } as InternalExtensionOverrides;
 }

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

@@ -17,6 +17,7 @@
 import { Extension, ExtensionDefinition } from './createExtension';
 import { ExternalRouteRef, RouteRef } from '../routing';
 import { FeatureFlagConfig } from './types';
+import { resolveExtensionDefinition } from './resolveExtensionDefinition';
 
 /** @public */
 export type AnyRoutes = { [name in string]: RouteRef };
@@ -71,22 +72,9 @@ export function createPlugin<
     routes: options.routes ?? ({} as Routes),
     externalRoutes: options.externalRoutes ?? ({} as ExternalRoutes),
     featureFlags: options.featureFlags ?? [],
-    extensions: (options.extensions ?? []).map(definition => {
-      const { name, namespace: _, kind, ...rest } = definition;
-
-      let id;
-      if (kind && name) {
-        id = `${kind}:${options.id}/${name}`;
-      } else if (kind) {
-        id = `${kind}:${options.id}`;
-      } else if (name) {
-        id = `${options.id}/${name}`;
-      } else {
-        id = options.id;
-      }
-
-      return { id, ...rest, $$type: '@backstage/Extension' };
-    }),
+    extensions: (options.extensions ?? []).map(def =>
+      resolveExtensionDefinition(def, { namespace: options.id }),
+    ),
   } as InternalBackstagePlugin<Routes, ExternalRoutes>;
 }
 

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

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2023 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Extension, ExtensionDefinition } from './createExtension';
+
+/** @internal */
+export function resolveExtensionDefinition<TConfig>(
+  definition: ExtensionDefinition<TConfig>,
+  context?: { namespace?: string },
+): Extension<TConfig> {
+  const { name, kind, namespace: _, ...rest } = definition;
+  const namespace = context?.namespace ?? definition.namespace;
+
+  if (!namespace) {
+    throw new Error(
+      `Extension must declare an explicit namespace as it could not be resolved from context, name=${name} kind=${kind}`,
+    );
+  }
+
+  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' };
+}