Add default feature type information to backstage metadata

Signed-off-by: Harrison Hogg <hhogg@spotify.com>

.changeset/hot-mice-cry.md

@@ -0,0 +1,6 @@
+---
+'@backstage/cli-node': patch
+'@backstage/cli': patch
+---
+
+Fixed an issue where default feature type information wasn't being added to package.json/exports before publishing if exports didn't exist beforehand

packages/cli-node/report.api.md

@@ -12,6 +12,9 @@ export type BackstagePackage = {
   packageJson: BackstagePackageJson;
 };
 
+// @public (undocumented)
+export type BackstagePackageFeatureType = (typeof packageFeatureType)[number];
+
 // @public
 export interface BackstagePackageJson {
   // (undocumented)
@@ -22,6 +25,7 @@ export interface BackstagePackageJson {
     pluginId?: string | null;
     pluginPackage?: string;
     pluginPackages?: string[];
+    features?: Record<string, BackstagePackageFeatureType>;
   };
   // (undocumented)
   bundled?: boolean;
@@ -112,6 +116,14 @@ export type LockfileDiffEntry = {
   range: string;
 };
 
+// @public
+export const packageFeatureType: readonly [
+  '@backstage/BackendFeature',
+  '@backstage/BackstagePlugin',
+  '@backstage/FrontendPlugin',
+  '@backstage/FrontendModule',
+];
+
 // @public
 export class PackageGraph extends Map<string, PackageGraphNode> {
   collectPackageNames(

packages/cli-node/src/monorepo/PackageGraph.ts

@@ -22,6 +22,24 @@ import { GitUtils } from '../git';
 import { Lockfile } from './Lockfile';
 import { JsonValue } from '@backstage/types';
 
+/**
+ * A list of the feature types we want to extract from the project
+ * and include in the metadata
+ *
+ * @public
+ */
+export const packageFeatureType = [
+  '@backstage/BackendFeature',
+  '@backstage/BackstagePlugin',
+  '@backstage/FrontendPlugin',
+  '@backstage/FrontendModule',
+] as const;
+
+/**
+ * @public
+ */
+export type BackstagePackageFeatureType = (typeof packageFeatureType)[number];
+
 /**
  * Known fields in Backstage package.json files.
  *
@@ -72,6 +90,11 @@ export interface BackstagePackageJson {
      * All packages that are part of the plugin. Must always and only be set for plugin packages and plugin library packages.
      */
     pluginPackages?: string[];
+
+    /**
+     * The feature types exported from the package, indexed by path.
+     */
+    features?: Record<string, BackstagePackageFeatureType>;
   };
 
   exports?: JsonValue;

packages/cli-node/src/monorepo/index.ts

@@ -16,10 +16,12 @@
 
 export { isMonoRepo } from './isMonoRepo';
 export {
+  packageFeatureType,
   PackageGraph,
   type PackageGraphNode,
   type BackstagePackage,
   type BackstagePackageJson,
+  type BackstagePackageFeatureType,
 } from './PackageGraph';
 export {
   Lockfile,

packages/cli/src/lib/__testUtils__/createFeatureEnvironment.ts

@@ -14,9 +14,8 @@
  * limitations under the License.
  */
 
-import { PackageRole } from '@backstage/cli-node';
+import { PackageRole, BackstagePackageFeatureType } from '@backstage/cli-node';
 import { Project } from 'ts-morph';
-import { BackstagePackageFeatureType } from '../typeDistProject';
 
 const mockEntryPoint = 'dist/index.d.ts';
 

packages/cli/src/lib/packager/productionPack.ts

@@ -188,7 +188,16 @@ async function rewriteEntryPoints(
         // This ensures that the `backstage` field is at the top of the
         // `exports` field in the package.json because order is important.
         // https://nodejs.org/docs/latest-v20.x/api/packages.html#conditional-exports
+        //
+        // Adding this to the `exports` field in the package.json is to temporarily
+        // support any existing behavior that relies on this, however not all packages
+        // have exports field in their package.json.
         exp = { backstage: defaultFeatureType, ...exp };
+
+        // Add the default feature type to the backstage metadata in the package.json
+        pkg.backstage = pkg.backstage ?? {};
+        pkg.backstage.features = pkg.backstage.features ?? {};
+        pkg.backstage.features[entryPoint.mount] = defaultFeatureType;
       }
     }
 

packages/cli/src/lib/typeDistProject.test.ts

@@ -14,12 +14,9 @@
  * limitations under the License.
  */
 
-import { PackageRole } from '@backstage/cli-node';
+import { PackageRole, BackstagePackageFeatureType } from '@backstage/cli-node';
 import createFeatureEnvironment from './__testUtils__/createFeatureEnvironment';
-import {
-  getEntryPointDefaultFeatureType,
-  BackstagePackageFeatureType,
-} from './typeDistProject';
+import { getEntryPointDefaultFeatureType } from './typeDistProject';
 
 describe('typeDistProject', () => {
   describe('for package role', () => {

packages/cli/src/lib/typeDistProject.ts

@@ -13,7 +13,11 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import { PackageRole } from '@backstage/cli-node';
+import {
+  BackstagePackageFeatureType,
+  packageFeatureType,
+  PackageRole,
+} from '@backstage/cli-node';
 import { resolve as resolvePath } from 'path';
 import { Project, SourceFile, SyntaxKind, ts, Type } from 'ts-morph';
 import { paths } from './paths';
@@ -35,17 +39,6 @@ const targetPackageRoles: PackageRole[] = [
   'node-library',
 ];
 
-// A list of the feature types we want to extract from the project
-// and include in the metadata
-const targetFeatureTypes = [
-  '@backstage/BackendFeature',
-  '@backstage/BackstagePlugin',
-  '@backstage/FrontendPlugin',
-  '@backstage/FrontendModule',
-] as const;
-
-export type BackstagePackageFeatureType = (typeof targetFeatureTypes)[number];
-
 export const getEntryPointDefaultFeatureType = (
   role: PackageRole,
   packageDir: string,
@@ -146,6 +139,6 @@ function isTargetFeatureType(
   type: string | BackstagePackageFeatureType,
 ): type is BackstagePackageFeatureType {
   return (
-    !!type && targetFeatureTypes.includes(type as BackstagePackageFeatureType)
+    !!type && packageFeatureType.includes(type as BackstagePackageFeatureType)
   );
 }