Choose an AWS Lambda integration tutorial
To build an API with Lambda integrations, you can use Lambda proxy integration or Lambda non-proxy integration.
In Lambda proxy integration, the input to the Lambda function can be expressed as any combination of request headers, path variables, query string parameters, body, and API configuration data. You only need to choose a Lambda function. API Gateway configures the integration request and integration response for you. Once set up, your API method can evolve without modifying the existing settings. This is possible because the backend Lambda function parses the incoming request data and responds to the client.
In Lambda non-proxy integration, you must ensure that input to the Lambda function is supplied as the integration request payload. You must map any input data the client supplied as request parameters into the proper integration request body. You might also need to translate the client-supplied request body into a format recognized by the Lambda function.
In either a Lambda proxy or a Lambda non-proxy integration, you can use a Lambda function in a different account from the account where you created your API.