Local testing permissions (IAM) for GCP Pub/Sub topic

[jitesh khuttan]

Hey guys!

I have a use case where I want to test the permissions (IAM) locally for GCP Pub/Sub topic. There is a sample code that official document provides.

I am trying to test my application locally using pub/sub emulator but it has some limitations (doesn't implement permissions).

As a solution, I have implemented a Fake pub/sub permission checker (flask server) - which would behave similar to real pub/sub IAM permission logic. I want my PublisherClient to connect with this fake server instead of pub/sub-emulator (or) real google pub/sub.

For ex: when you set PUBSUB_EMULATOR_HOST environment variable, below code would connect you to pub/sub emulator instead of real google pub/sub.

from google.cloud.pubsub_v1 import PublisherClient 

publisher = PublisherClient()

I would want my code to connect with my fake server when I write same above code. Is it possible to configure this?

Would really appreciate the help!

[Efim (Cloud Platform Support)]

I searched for either on premises Cloud Pub/Sub server, or connecting to a third-party server without success.

Therefore, I created [this feature request](https://issuetracker.google.com/215878712). Please use it for further communication on the subject. 

Kindly note though, that at the moment there is no time estimate for the feature's implementation.