How to authenticate to oauth2-proxy via cURL or POSTMAN

I have my service set behind oauth2-proxy and I am using version 4.0.0.

I am trying to hit an API behind the service, but unfortunately, I always get a 403 forbidden error because of oauth2-proxy being in the way.

I am looking for a way to authenticate via g-suite using oauth2-proxy and generate a token that I can then use for the service.

Does oauth2-proxy support any kind of way to authenticate via cURL or POST call?

Solution

It feels to me that your deployment separation is not right. OAuth has a strong focus on separation of web and API concerns. The oauth2-proxy utility is a web client and should not be deployed in front of APIs since that can limit your options.

SUBOPTIMAL DEPLOYMENT

API is hosted behind oauth2-proxy
oauth2-proxy issues redirects to the browser
Browser clients can handle redirects and users can login
After a browser login oauth2-proxy issues a cookie
oauth2-proxy translates cookies to tokens when JavaScript calls APIs
Mobile apps or API test clients cannot call the API

OPTIMIZED DEPLOYMENT

Web static content is hosted behind oauth2-proxy
oauth2-proxy issues redirects to the browser
Browser clients can handle redirects and users can login
After a browser login oauth2-proxy issues a cookie
oauth2-proxy translates cookies to tokens when JavaScript calls APIs
APIs have their own internet entry points that require access tokens
Mobile apps or API test clients can call APIs with an access token

If I'm misunderstanding anything, maybe clarify your question and post back.