How do I set up a Google Cloud Function with Authentication?

Question

Disclaimer: I'm completely new to Google Cloud Functions and serverless functions in general.

I've set up a basic Google Cloud Function, set it to HTTPS trigger and Require Authentication, and given the service account and my account the cloud function invoker role.

However, whenever I use Postman to sent an HTTP request to the function using my oauth2 token, I get a 401 Unauthorized error.

I've also followed the steps here: https://cloud.google.com/functions/docs/securing/authenticating

to create and download the service account key and make an HTTP request using cURL and get the same error.

How do I need to set this up so that authorized users can send HTTP requests to this function?

Here's what I'm doing:

$gcloud auth login (to log in with my account with cloud invoker permission)
$curl https://my-trigger-url \ -H "Authorization: bearer $(gcloud auth print-identity-token)"

Answer 1

Guillaume found the solution:

My cURL syntax to trigger the Cloud Function needed the -H "Authorization: bearer $(gcloud auth print-identity-token)" before the URL instead of after, which is the opposite of Google's own documentation.

Thanks for your help.