create-app: Update techdocs-backend, add changesets

.changeset/curly-emus-own.md

@@ -0,0 +1,6 @@
+---
+'@backstage/create-app': patch
+---
+
+techdocs-backend: Simplified file, removing individual preparers and generators.
+techdocs-backend: UrlReader is now available to use in preparers.

.changeset/thirty-papayas-attack.md

@@ -0,0 +1,36 @@
+---
+'@backstage/techdocs-common': minor
+'@backstage/plugin-techdocs-backend': minor
+---
+
+In your Backstage app, `packages/backend/plugins/techdocs.ts` file has now been simplified,
+to remove registering individual preparers and generators.
+
+Please update the file when upgrading the version of `@backstage/plugin-techdocs-backend` package.
+
+```typescript
+const preparers = await Preparers.fromConfig(config, {
+  logger,
+  reader,
+});
+
+const generators = await Generators.fromConfig(config, {
+  logger,
+});
+
+const publisher = await Publisher.fromConfig(config, {
+  logger,
+  discovery,
+});
+```
+
+You should be able to remove unnecessary imports, and just do
+
+```typescript
+import {
+  createRouter,
+  Preparers,
+  Generators,
+  Publisher,
+} from '@backstage/plugin-techdocs-backend';
+```

packages/create-app/templates/default-app/packages/backend/src/plugins/techdocs.ts

@@ -1,10 +1,7 @@
 import {
   createRouter,
-  DirectoryPreparer,
   Preparers,
   Generators,
-  TechdocsGenerator,
-  CommonGitPreparer,
   Publisher,
 } from '@backstage/plugin-techdocs-backend';
 import { PluginEnvironment } from '../types';
@@ -14,22 +11,28 @@ export default async function createPlugin({
   logger,
   config,
   discovery,
+  reader,
 }: PluginEnvironment) {
-  const generators = new Generators();
-  const techdocsGenerator = new TechdocsGenerator(logger, config);
-
-  generators.register('techdocs', techdocsGenerator);
-
-  const preparers = new Preparers();
-  const directoryPreparer = new DirectoryPreparer(logger);
-  const commonGitPreparer = new CommonGitPreparer(logger);
+  // Preparers are responsible for fetching source files for documentation.
+  const preparers = await Preparers.fromConfig(config, {
+    logger,
+    reader,
+  });
 
-  preparers.register('dir', directoryPreparer);
-  preparers.register('github', commonGitPreparer);
-  preparers.register('gitlab', commonGitPreparer);
+  // Generators are used for generating documentation sites.
+  const generators = await Generators.fromConfig(config, {
+    logger,
+  });
 
-  const publisher = Publisher.fromConfig(config, logger, discovery);
+  // Publisher is used for
+  // 1. Publishing generated files to storage
+  // 2. Fetching files from storage and passing them to TechDocs frontend.
+  const publisher = await Publisher.fromConfig(config, {
+    logger,
+    discovery,
+  });
 
+  // Docker client (conditionally) used by the generators, based on techdocs.generators config.
   const dockerClient = new Docker();
 
   return await createRouter({