How would one log into an AWS User Pool from Unreal Engine?

Question

I'm very, very new to the networking and AWS side of things, but experimenting a bit with some concepts. I was wondering if anyone had suggestions for the following use case. I'm in an experimental capacity at the moment, so these atypical practices have their reasons. Anyway, thanks for any guidance y'all can provide!

1. A person in Unreal enters some credentials, e.g., "username" and "password."
2. I verify that in AWS with a Cognito User Pool and provide them with an access token. Optionally, maybe I access IAM/Cognito directly to log into a User Pool identity.
3. Upon verifying that request, I serve them links to download content, e.g., from S3. The links could have further verification with tokens and such.

My initial plan was to send some HTTP(S) requests to Lambda functions, but Lambda doesn't appear to support Authenticating a user by receiving credentials. I could be totally crazy of course, and may have just missed that part of the documentation.

So, I suppose my questions are: from Unreal Engine, what would the best way be for simply submitting user credentials and receiving a token in return? And, once I have that token, what's the best way to then route that token and user pool to an S3 bucket for downloading some special content? I feel like making some serverless web app with no front-end as a surrogate for Unreal requesting just two things would be super overkill. But maybe y'all feel differently, and I'm open to suggestions.

Thanks! Definitely expect some follow-up questions as I'm quite new to the AWS space, heh. If this is an inappropriate venue for questions like this, I'm happy to close the thread and go elsewhere.

Answer 1

I feel like making some serverless web app with no front-end as a surrogate for Unreal requesting just two things would be super overkill.

Not really. You need:

• One Lambda function to get the content from S3. 10 lines of code.
• One API Gateway setup. Configure this with an Authorizer which refers to your Cognito User Pool.

Your client code then calls the AWS Cognito APIs to get its token, then the API Gateway endpoint to get the content, passing the Cognito token to API Gateway.