Skip to content

Instantly share code, notes, and snippets.

@DavidWells
Created June 28, 2018 20:48
Show Gist options
  • Save DavidWells/99216c20cdb3df334d5b98ff19644fa2 to your computer and use it in GitHub Desktop.
Save DavidWells/99216c20cdb3df334d5b98ff19644fa2 to your computer and use it in GitHub Desktop.
How to do a 301 redirect from an AWS lambda function
exports.handler = (event, context, callback) => {
const response = {
statusCode: 301,
headers: {
Location: 'https://google.com',
}
};
return callback(null, response);
}
@AllanOricil
Copy link

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;
};

image

@AllanOricil
Copy link

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

@GokulDharumar
Copy link

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

@juantelez
Copy link

Thanks David!!
This helped me a lot!

@wxgeorge
Copy link

wxgeorge commented Mar 10, 2022

@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.

截圖 2020-05-07 上午9 34 24

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?

@samirm
Copy link

samirm commented Sep 6, 2022

thank you!

@Divuzki
Copy link

Divuzki commented Sep 12, 2022

Great for:

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

Rick Rolls 😂

@lzhou0
Copy link

lzhou0 commented Sep 26, 2022

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?

@Divuzki
Copy link

Divuzki commented Sep 27, 2022

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?

@BuffMcBigHuge
Copy link

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"
        }
    ]
}

@anandakumarpalanisamy
Copy link

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'?

@renchris
Copy link

renchris commented Nov 21, 2022

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

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment