Lemna

Quickly scaffold and deploy AWS Lambda handlers powered by Javascript or Typescript.

Lemna will transpile, bundle and upload your code - no more tedious code deploying to Lambda.

Dependencies will be bundled into your code using esbuild (https://esbuild.github.io/), so only required code is uploaded (dev dependencies will be ignored).

Installation

npm i lemna -g

Scaffold new Lambda function

lemna init

This will setup a function folder with:

• package.json
• Typescript (+ tsconfig)
• Lambda typings (@types/aws-lambda)
• Basic Lambda handler (src/index.ts)
• Lemna config (lemna.config.json)

Deploying

Create a .env file and place your AWS credentials in it. Then run:

lemna deploy

Use a custom path

lemna deploy my-app/lemna.config.json

Use glob patterns

lemna deploy lambdas/**/lemna.config.json

Use CommonJS module as config

// lemna.config.js
module.exports = {
  entryPoint: "path to .js file",
  function: {
    name: "lambda-function-name",
    runtime: "nodejs14.x",
  },
};

lemna deploy lemna.config.js

Deploy multiple functions

lemna deploy firstconfig.json secondconfig.json [...]

Use in existing project

• Create a lemna.config.json, including at least:

{
  "entryPoint": "path to .js file",
  "function": {
    "name": "lambda-function-name",
    "runtime": "nodejs14.x"
  }
}

List functions

lemna ls --page=0

Print function details

lemna show my-function

Delete function

lemna rm my-function

Debugging/Tracing

Run with LEMNA_LOG_LEVEL=error/warn/info/verbose/debug/silly

LEMNA_LOG_LEVEL=silly lemna deploy

Required AWS policies

Required:

• iam:PassRole
• lambda:CreateFunction
• lambda:UpdateFunctionCode
• lambda:UpdateFunctionConfiguration
• lambda:GetFunction
• lambda:GetFunctionConfiguration

Optional:

• lambda:ListFunctions (for ls command)
• lambda:DeleteFunction (for rm command)