How to do a 301 redirect from an AWS lambda function

aws-lambda-redirect.js

exports.handler = (event, context, callback) => {
   const response = {
    statusCode: 301,
    headers: {
      Location: 'https://google.com',
    }
  };

  return callback(null, response);
}

When I use this example everything woks locally (Im using SAM CLI), but when I deploy to AWS I keep getting status code 502. Would you know what is the problem? inside cloud watch there is no error

exports.handler = async (event) => {
    const response = {
        statusCode: 301,
        headers: {
            Location: 'https://google.com'
        }
    };
    
    return response;
};

II found the reason, I was adding additional headers. It can't have other headers, only the Location.

How to fix the same issue for httpapi? i get the json printed on the page instead of redirect

Thanks David!!
This helped me a lot!

@diegopamio, and the following

WARNING:

You have to check the choice of "Use lambda proxy integration" while binding the method to lambda in API gateway, or you will get only JSON.

Following are the snapshot.

Further to this -

if you're looking for the docs on why a lambda like this "works", see https://docs.aws.amazon.com/apigateway/latest/developerguide/set-up-lambda-proxy-integrations.html. Lambdas are not "HTTP enabled" by default, but a key way they can be is through a proxy integration with an API Gateway.

This gist is an example how a lambda can conform to an API Gateway's expectations around proxy integrations.

Those docs describe how the output of a lambda is mapped to an HTTP response
(and also describes how HTTP requests are mapped into the event).

To check if you understand: is the use of callback in the gist necessary?

thank you!

Great for:

• Download URLS
• Link shortening tools
• Unauthorized calls
• Rick rolls

Rick Rolls 😂

Tried out this piece of code, but receiving this error:

{
  "errorType": "Runtime.ImportModuleError",
  "errorMessage": "Error: Cannot find module 'index'\nRequire stack:\n- /var/runtime/index.mjs",
  "trace": [
    "Runtime.ImportModuleError: Error: Cannot find module 'index'",
    "Require stack:",
    "- /var/runtime/index.mjs",
    "    at _loadUserApp (file:///var/runtime/index.mjs:951:17)",
    "    at async Object.UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:976:21)",
    "    at async start (file:///var/runtime/index.mjs:1137:23)",
    "    at async file:///var/runtime/index.mjs:1143:1"
  ]

Anyone else come across this Runtime.ImportModuleError error?

Tried out this piece of code, but receiving this error:

{
  "errorType": "Runtime.ImportModuleError",
  "errorMessage": "Error: Cannot find module 'index'\nRequire stack:\n- /var/runtime/index.mjs",
  "trace": [
    "Runtime.ImportModuleError: Error: Cannot find module 'index'",
    "Require stack:",
    "- /var/runtime/index.mjs",
    "    at _loadUserApp (file:///var/runtime/index.mjs:951:17)",
    "    at async Object.UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:976:21)",
    "    at async start (file:///var/runtime/index.mjs:1137:23)",
    "    at async file:///var/runtime/index.mjs:1143:1"
  ]

Anyone else come across this Runtime.ImportModuleError error?

Can you show the code causing the problem?

Came across this recently. The proper Lambda Edge function should look like:

exports.handler = (event, context, callback) => {
   const response = {
    status: 301,
    headers: {
        location: [{
            key:   'Location', 
            value: 'https://google.com',
        }],
    },
  };
  return callback(null, response);
}

Furthermore, the Role Trust Relationship for your Lambda should include:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Principal": {
                "Service": [
                    "lambda.amazonaws.com",
                    "edgelambda.amazonaws.com"
                ]
            },
            "Action": "sts:AssumeRole"
        }
    ]
}

Tried out this piece of code, but receiving this error:

{
  "errorType": "Runtime.ImportModuleError",
  "errorMessage": "Error: Cannot find module 'index'\nRequire stack:\n- /var/runtime/index.mjs",
  "trace": [
    "Runtime.ImportModuleError: Error: Cannot find module 'index'",
    "Require stack:",
    "- /var/runtime/index.mjs",
    "    at _loadUserApp (file:///var/runtime/index.mjs:951:17)",
    "    at async Object.UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:976:21)",
    "    at async start (file:///var/runtime/index.mjs:1137:23)",
    "    at async file:///var/runtime/index.mjs:1143:1"
  ]

Anyone else come across this Runtime.ImportModuleError error?

Have you tried naming the js file as 'index.js'?

For those using API Gateway + Lambda, I followed this: https://aws.amazon.com/premiumsupport/knowledge-center/malformed-502-api-gateway/

const response = {
    "statusCode": 200,
    "headers": {
        "my_header": "my_value"
    },
    "body": JSON.stringify(responseBody),
    "isBase64Encoded": false
};

The four fields of statusCode, headers, body, and isBase64Encoded were required