This is the React frontend for the default Backstage software catalog. This package supplies interfaces related to listing catalog entities or showing more information about them on entity pages.

This @backstage/plugin-catalog 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/app/package.json, in the dependencies block, for @backstage/plugin-catalog. The instructions below walk through restoring the plugin, if you previously removed it.

# From your Backstage root directory
yarn --cwd packages/app add @backstage/plugin-catalog

Add the two pages that the catalog plugin provides to your app. You can choose any name for these routes, but we recommend the following:

// packages/app/src/App.tsx
import {
  CatalogIndexPage,
  CatalogEntityPage,
} from '@backstage/plugin-catalog';
import { entityPage } from './components/catalog/EntityPage';

<FlatRoutes>
+  <Route path="/catalog" element={<CatalogIndexPage />} />
+  <Route path="/catalog/:namespace/:kind/:name" element={<CatalogEntityPage />}>
+  {/*
+    This is the root of the custom entity pages for your app, refer to the example app
+    in the main repo or the output of @backstage/create-app for an example
+  */}
+    {entityPage}
+  </Route>
  ...
</FlatRoutes>

The catalog plugin also has one external route that needs to be bound for it to function: the createComponent route which should link to the page where the user can create components. In a typical setup the create component route will be linked to the scaffolder plugin's template index page:

// packages/app/src/App.tsx
+import { catalogPlugin } from '@backstage/plugin-catalog';
+import { scaffolderPlugin } from '@backstage/plugin-scaffolder';

const app = createApp({
  // ...
  bindRoutes({ bind }) {
+    bind(catalogPlugin.externalRoutes, {
+      createComponent: scaffolderPlugin.routes.root,
+    });
  },
});

You may also want to add a link to the catalog index page to your application sidebar:

// packages/app/src/components/Root/Root.tsx
+import HomeIcon from '@material-ui/icons/Home';

export const Root = ({ children }: PropsWithChildren<{}>) => (
  <SidebarPage>
    <Sidebar>
+      <SidebarItem icon={HomeIcon} to="catalog" text="Home" />
      ...
    </Sidebar>

This frontend 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 frontend plugin itself.

To evaluate the catalog and have a greater amount of functionality available, run the entire Backstage example application from the root folder:

yarn dev

This will launch both frontend and backend in the same window, populated with some example entities.

• catalog-backend provides the backend API for this frontend.