aws-lambda-packager

Synopsis

A node module to package node js lambdas.

Motivation

The size of a node js lambda bundle is critical when it comes to cold starts. Thus its imperative that we only bundle bare minimum files. aws-lambda-packager attempts to solve this problem. Key features includes the following

• Intelligently package required npm dependencies
• Add any additional resources as applicable
• works with flat node_modules or with hierarchical node_modules

Getting Started

Prerequisites

The project assumes that one must have node js installed on the target environment.

Build and Run

Build Instructions

No special build steps are required.

Tests

To run the tests, you can use the command

   npm test

The above triggers tests/index.test.js using mocha test framework.

Usage

Cli Usage

npm install -g aws-lambda-packager

Form your project dir

aws-lambda-packager

The above will run package modules using default configurations. The default configurations assumes the following

1. main js file shall be derived from package.json main attribute
2. source dir shall be either of src | modules | lib
3. destination directory shall be dist
4. destination file shall be derived from package.json as .zip

The above behaviour can be tweaked using a configuration file. The config file must be called package.config and must be present on root dir from where packager will be run. The configuration file looks something as shown below

{
	"include" :[
		{
			"source": "modules",
			"dest": "collector/modules"
		},
		{
			"source": "config",
			"dest": "config"
		},
		{
			"source": "cfn",
			"dest": "cfn"
		},
		{
			"source": "binaries/run.bat",
			"dest": "run.bat"
		},
		{
			"source": "binaries/run.sh",
			"dest": "run.sh"
		},
		{
			"source": "contents",
			"dest": "contents"
		}
	],
	"destination_root":"collector"
}

destination_root

This attribute can be used to define a single root within which all project files shall be placed. So, if this attribute is set, index.js( main ) and node_modules shall be placed under this directory

include

This attribute can be used too add any other dependencies that might be needed.

node_modules

The packager shall start with top level package.json and traverse all package.json in the project dir to bundle required packages. The packager only bundles dependencies, bundleDependency, bundledDependencies.

Code usage

const DependencyScanner = require('aws-lambda-packager');
const ds = new DependencyScanner();

ds.scanv3("SOURCE_DIR", function (err) {
    // do something on completion
}, "DEST_DIR");

Limitation

There may be instances when an external npm dependency does not correctly defines its dependencies. For example a required dependency may be by mistake mentioned as dev-dependency. This will cause the required package to not get bundled. To work around this problem, you can add the trouble some dependency as top level dependency.

Contributors

Feel free to fork/clone the repo and provide your contributions. In order to make contributions, please follow these steps

1. Submit an issue describing your proposed changes
2. The repo owner will respond to your issue promptly
3. If your proposed change is accepted, fork the repo, develop and test your changes
4. Submit a pull request

License

Lambda Packager is under the Apache License 2.0. See the LICENSE file for details.