I have an Angular web app running on Cloud Run (nginx webserver) (more info here) from which I want to get access token from the GCP metadata server. I have tried to make a call to https://metadata.google.internal ( using curl from Cloud Shell) but the connection was rejected. Calls to HTTP are working well.
When I make the call from my app (which is loaded over https) to the metadata server over HTTP - logically I get a mixed content error. When trying to access the metadata server over HTTPS - I am getting error 504 Gateway timeout, I assume due to the reason that the metadata server refuses the calls on HTTPS.
I will really appreciate any idea of how to solve this issue.
The URL endpoint metadata.google.internal is only accessible from inside the instance (Cloud Run). This endpoint is not accessible outside of the instance such as via an HTTP or HTTPS call. A clue is the TLD (Top Level Domain) internal.
If you want to access this endpoint remotely via a web browser, you will need to make a request from the browser to Cloud Run (an endpoint in your code) which then makes the internal request to the metadata server and returns the response to the client.