Lambda-cfn NPM

lambda-cfn

Quickly define Lambda functions and supporting resources via a javascript CloudFormation template.

Synopsis

In a file named like myTemplate.template:

var lambdaCfn = require('lambda-cfn');

module.exports = lambdaCfn(
  [
    'myHandler.js',
  ],
  {
    "AWSTemplateFormatVersion": "2010-09-09",
    "Description": "my stack"
  }
);

where in myHandler.js you've exported:

module.exports.fn - a function which takes in event, context, callback and which will get called by Lambda. See lambda documentation for help on using context or the callback.
module.exports.config - allows you to define some configuration for your Lambda function. See the rules spec for all options.

After uploading a zip of your project to a location in Lambda, you can then deploy this javascript CloudFormation template with cfn-config to deploy your function.

See the patrol README for more examples and the rules spec for a complete reference.

Why

AWS Lambda simplifies deploying code on AWS by eliminating the need to run EC2s. However, you still need to:

Monitor the function and know when it fails
Grant the function proper IAM policy permissions
Schedule the function, or connect it to an event source
Capture all of this in a CloudFormation template

lambda-cfn provides for a simplified interface for defining all of the above, and when used in combination with cfn-config, offers a command line interface for deploying and updating the CloudFormation template in which your lambda functions and supporting resources are captured.

Instead of directly writing a CloudFormation template, cfn-config is able to read a javascript file, and, if that javascript file implements lambda-cfn, cfn-config + lambda-cfn turn that file into a valid CloudFormation template.

lambda-cfn adheres to a rules spec in order for a Lambda function, supporting resources, and configuration to be defined in javascript files, which can then be expanded into CloudFormation template JSON.