node.js - AWS Lambda fails to return PDF file

Question

I have created a lambda function using serverless. This function is fired via API Gateway on a GET request and should return a pdf file from a buffer. I'm using html-pdf to create the buffer and trying to return the pdf file with the following command

  let response = {
    statusCode: 200,
    headers: {'Content-type' : 'application/pdf'},
    body: buffer.toString('base64'),
    isBase64Encoded : true,
  };
  return callback(null, response);

but the browser is just failing to load the pdf, so I don't know exactly how to return the pdf file directly to the browser. Could'nt find a solution for that.

Answer 1

well, I found the answer. The settings in my response object are fine, I just had to manually change the settings in API Gateway for this to work in the browser. I have added "*/*" to binary media types under the binary settings in API Gateway console

API GATEWAY

1. just log into your console
2. choose your api
3. click on binary support in the dropdown
4. edit binary media type and add "*/*"

FRONTEND

opening the api url in new tab (target="_blank"). Probably the browser is handling the encoded base 64 response, In my case with chrome, the browser just opens the pdf in a new tab exactly like I want it to do.