I am trying to obtain data from a web service (publisher).
The web service lets me send the data (message) to any url through a webhook. My plan is to send it to a Google Pub/Sub topic.
However, Google Pub/Sub is not recognizing this third-party web service. It is returning a http 401 response code, meaning that the web service is not authenticated.
My question is, How can I authenticate it?
Authentication for requests made to Google Cloud Pub/Sub or any other of the Google Cloud Platform services can be accomplished in a couple of different ways. In your case, where you want to make a direct request via the REST API, you'll need to create a service account and authenticate via OAuth 2.0. The Using OAuth 2.0 for Server to Server Applications guide details the process. If the web service you are using supports OAuth 2.0 authentication for requests it makes, then you should basically be set. If it does not, then you will have to take care of acquiring access tokens (and acquiring new ones when they expire) manually.
