APIs explorer with pagination

Feature Suggestion

Add pagination that is supported by catalog-backend to api-docs plugin.

Possible Implementation

Extend api-docs components and catalog-client to support pagination.

Context

At Zalando, we would like to add api-docs plugin to our system. The absence of pagination prevents us to introduce it since we are having >1k APIs. If there is no ongoing work or if it would be useful to other people, I would be happy to contribute to it.

[freben]

I want to explore a model where columns and filters explicitly ask for the fields that they want. That way the surrounding context can choose to fetch exactly the necessary fields (the union of all requested) and no more.

[kuangp]

FYI for others, I’m using the following workaround to override the catalogApiRef on my Backstage instance to strip out loading API definitions in the explorer view:

export class CatalogClientExt extends CatalogClientWrapper {
  async getEntities(
    request?: CatalogEntitiesRequest,
    options?: CatalogRequestOptions,
  ): Promise<CatalogListResponse<Entity>> {
    const filter = [request?.filter].flat().filter(Boolean);
    if (request && !request.fields && filter.length === 1 && filter[0]?.kind === 'api') {
      request.fields = [
        'apiVersion',
        'kind',
        'metadata',
        'relations',
        'status',
        'spec.lifecycle',
        'spec.owner',
        'spec.type',
        'spec.system',
      ];
    }
    return super.getEntities(request, options);
  }
}

// app/src/apis.ts
...
  createApiFactory({
    api: catalogApiRef,
    deps: { discoveryApi: discoveryApiRef, identityApi: identityApiRef },
    factory: ({ discoveryApi, identityApi }) =>
      new CatalogClientExt({
        client: new CatalogClient({ discoveryApi }),
        identityApi,
      }),
  }),
...

This extends the default catalog client to modify the request made by the API explorer page. I also put up this PR to export CatalogClientWrapper in order to inherit from it (I’ve forked the class for the time being). Hopefully this also helps others for now.

I think the attachment store and actual support for pagination is the most appropriate solution here for optimizing load times.