When I try to use an Amazon API Gateway REST API, I receive a 403 "Missing Authentication Token" error message. How can I resolve these issues?
how do I check the API Gateway response when a request is been made to a method after returning a Missing Authentication Token error?
what could be the cause?
API Gateway REST API endpoints return a Missing Authentication Token error for the following reasons:
- An API request was made to a method or resource that does not exist.
- The API is either set up with a changed Gateway response or the response comes from a backend integration.
- API requests are not signed when AWS Identity and Access Management (IAM) authentication is turned on for API methods.
How do I resolve it
Check that you are delivering the proper HTTP method request to your REST API endpoint.
A GET HTTP method request is automatically sent when testing a REST API endpoint from a web browser.
To test the POST HTTP method request, use another HTTP client. For instance, postman or curl.
POST HTTP method request example curl command
$ curl -X POST <API URL> -d <request body>
Example of using Postman POST HTTP method request