AWS Lambda handler for Grant

var grant = require('grant').aws({
  config: {/*Grant configuration*/}, session: {secret: 'grant'}
})

exports.handler = async (event) => {
  var {redirect, response} = await grant(event)
  return redirect || {
    statusCode: 200,
    headers: {'content-type': 'application/json'},
    body: JSON.stringify(response)
  }
}

Also available for Azure, Google Cloud, Vercel

ES Modules and TypeScript

The config key expects your Grant configuration.

Grant relies on the request path to determine the provider name and any static override being used. The following event keys are being used to determine the request path:

Additionally the prefix specified in your Grant configuration is used to generate the correct redirect_uri in case it is not configured explicitly.

However, AWS is inconsistent in the way it sets those values under different circumstances, and you may have to print those event keys and adjust your Grant configuration accordingly. A few known cases:

https://[id].execute-api.[region].amazonaws.com/[stage]/connect/google
https://[id].execute-api.[region].amazonaws.com/[stage]/connect/google/callback

{
  "defaults": {
    "origin": "https://[id].execute-api.[region].amazonaws.com",
    "prefix": "/[stage]/connect"
  },
  "google": {}
}

https://amazing.com/connect/google
https://amazing.com/connect/google/callback

{
  "defaults": {
    "origin": "https://amazing.com",
    "prefix": "/connect"
  },
  "google": {}
}

{
  "defaults": {
    "origin": "https://amazing.com",
    "prefix": "/stage/connect"
  },
  "google": {
    "redirect_uri": "https://amazing.com/connect/google/callback"
  }
}

https://amazing.com/v1/connect/google
https://amazing.com/v1/connect/google/callback

{
  "defaults": {
    "origin": "https://amazing.com",
    "prefix": "/v1/connect"
  },
  "google": {}
}

{
  "defaults": {
    "origin": "https://amazing.com",
    "prefix": "/stage/connect"
  },
  "google": {
    "redirect_uri": "https://amazing.com/v1/connect/google/callback"
  }
}

When running locally the following routes can be used:

http://localhost:3000/[stage]/connect/google
http://localhost:3000/[stage]/connect/google/callback

The session key expects your session configuration:

• The default cookie store is used unless you specify a store implementation!
• Using the default cookie store may leak private data!
• Implementing an external session store is recommended for production deployments!

Example session store implementation using Firebase:

var request = require('request-compose').client

var path = process.env.FIREBASE_PATH
var auth = process.env.FIREBASE_AUTH

module.exports = {
  get: async (sid) => {
    var {body} = await request({
      method: 'GET', url: `${path}/${sid}.json`, qs: {auth},
    })
    return body
  },
  set: async (sid, json) => {
    await request({
      method: 'PATCH', url: `${path}/${sid}.json`, qs: {auth}, json,
    })
  },
  remove: async (sid) => {
    await request({
      method: 'DELETE', url: `${path}/${sid}.json`, qs: {auth},
    })
  },
}

The AWS Lambda handler for Grant accepts:

The AWS Lambda handler for Grant returns:

Different session store types were used for example purposes only.

All variables at the top of the Makefile with value set to ... have to be configured:

• profile - AWS_PROFILE to use for managing AWS resources, not used for local development

• firebase_path - Firebase path of your database, required for transport-session and dynamic-state examples

https://[project].firebaseio.com/[prefix]

• firebase_auth - Firebase auth key of your database, required for transport-session and dynamic-state examples

{
  "rules": {
    ".read": "auth == '[key]'",
    ".write": "auth == '[key]'"
  }
}

• api_type - defaults to http-api, available for rest-api as well

• event_format - defaults to 1.0, available for 2.0 as well, applicable for http-api

All variables can be passed as arguments to make as well:

make plan example=transport-querystring ...

# build example locally
make build-dev
# run example locally
make run-dev

# build Grant lambda for deployment
make build-grant
# build callback lambda for transport-querystring and transport-session examples
make build-callback
# execute only once
make init
# plan before every deployment
make plan
# apply plan for deployment
make apply
# cleanup resources
make destroy