lambda_proxy

A Rust-based AWS Lambda function that proxies REST API requests.

AWS Lambda Proxy in Rust

This repository contains an AWS Lambda function written in Rust that acts as a proxy for REST APIs. The function forwards incoming HTTP requests to a specified target host. The target host can be set either via a header (X-Target-Host) or an environment variable (TARGET_HOST). The function also checks for an API key in the header (X-API-Key) to authorize requests and prevents recursive calls by ensuring the target host is not the same as the source host.

Features

• Authorization: Checks for an X-API-Key header and compares it with the API_KEY environment variable. If the API keys do not match, it returns a 401 Unauthorized response.
• Target Host Configuration: The target host for forwarding the request can be specified via the X-Target-Host header or the TARGET_HOST environment variable as host:port (localhost:1234 or without port example.com).
• HTTP Method Support: Supports various HTTP methods (GET, POST, PUT, DELETE) and returns the response from the target host back to the client.

Project Structure

• src/main.rs: The main Rust source file containing the Lambda function logic.
• Cargo.toml: The Cargo configuration file specifying dependencies and project metadata.
• tests: Contains unit tests for the Lambda function.

Development

Build

cargo build --release --target aarch64-unknown-linux-musl && sam build

Deploy

sam deploy --guided

Note on Deployment

Sometimes after deployment, the endpoint may return {"Message":"Forbidden"}. This is a known AWS issue. To resolve it, go to the AWS Management Console, navigate to the Lambda function's configuration, find the Function URL settings, and resave the configuration by clicking "Edit" and then "Save".

Contributing

Contributions are welcome! Please feel free to submit a pull request or open an issue to discuss changes.

License

This project is licensed under the MIT License. See the LICENSE file for details.