This is the backend for the default Backstage software catalog. This provides an API for consumers such as the frontend catalog plugin.
It comes with a builtin database-backed implementation of the catalog that can store and serve your catalog for you.
It can also act as a bridge to your existing catalog solutions, either ingesting data to store in the database, or by effectively proxying calls to an external catalog service.
This @backstage/plugin-catalog-backend package comes installed by default in
any Backstage application created with npx @backstage/create-app, so
installation is not usually required.
To check if you already have the package, look under
packages/backend/package.json, in the dependencies block, for
@backstage/plugin-catalog-backend. The instructions below walk through
restoring the plugin, if you previously removed it.
# From your Backstage root directory
yarn --cwd packages/backend add @backstage/plugin-catalog-backend
Then add the plugin to your backend, typically in packages/backend/src/index.ts:
const backend = createBackend();
// ...
backend.add(import('@backstage/plugin-catalog-backend'));
In the old backend system there's a bit more wiring required. You'll need to
create a file called packages/backend/src/plugins/catalog.ts with contents
matching catalog.ts in the create-app template.
With the catalog.ts router setup in place, add the router to
packages/backend/src/index.ts:
+import catalog from './plugins/catalog';
async function main() {
...
const createEnv = makeCreateEnv(config);
+ const catalogEnv = useHotMemoize(module, () => createEnv('catalog'));
const scaffolderEnv = useHotMemoize(module, () => createEnv('scaffolder'));
const apiRouter = Router();
+ apiRouter.use('/catalog', await catalog(catalogEnv));
...
apiRouter.use(notFoundHandler());
At this point the catalog-backend is installed in your backend package, but
you will not have any catalog entities loaded. See Catalog Configuration
for how to add locations, or copy the catalog locations from the create-app template
to get up and running quickly.
This backend plugin can be started in a standalone mode from directly in this
package with yarn start. However, it will have limited functionality and that
process is most convenient when developing the catalog backend plugin itself.
To evaluate the catalog and have a greater amount of functionality available, run the entire Backstage example application from the root folder:
# in one terminal window, run this from from the very root of the Backstage project
cd packages/backend
yarn start
This will launch both frontend and backend in the same window, populated with some example entities.