This example will attempt to fetch a list of topics using the google gRPC protobuf specification. This will use an OAuth token and TLS to fetch the list of topics.

First, you must generate a access token via the OAuth playground. From here select the Cloud Pub/Sub API v1 and its urls as the scope. This will start the OAuth flow. Then you must hit the Exchange authorization code for tokens button to generate an access_token which will show up in the HTTP response to the right under the access_token field in the response json.

Once, you have this token you must fetch your GCP project id which can be found from the main page on the dashboard. When you have both of these items you can run the example like so:

GCP_AUTH_TOKEN="<access-token>" cargo run --bin gcp-client -- <project-id>