@polarity-dev/lambda-local-runner

Lambda Local Runner

This project provides a local environment to run and test AWS Lambda functions using Node.js.

Usage

npm install -g @polarity-dev/lambda-local-runner
echo '{ "my-function": "/path/to/function.js" }' > lambda.json
lambda-local --config lambda.json

Build from source

TL;DR

npm install
cp lambda-sample.json lambda.json
npm run dev a

Requirements

• Node.js

Setup Instructions

• Install Dependencies. Run the following command to install necessary dependencies:

  npm install
  

• Create Lambda Mapping Settings. Copy the sample Lambda configuration file:

  cp lambda-sample.json lambda.json
  

  Then, fill in the details for the Lambda function you intend to manage.

Running the Server

To start the local Lambda server, execute:

npm run dev

Once the server is running, you can invoke your local Lambda functions by using localhost:6789 as the endpoint. Below is an example of how to call a Lambda function using the AWS SDK for JavaScript:

import { LambdaClient, InvokeCommand } from "@aws-sdk/client-lambda"

const lambdaClient = new LambdaClient({
    region: "eu-west-1",
    endpoint: "http://localhost:6789",
})

lambdaClient.send(
    new InvokeCommand({
        FunctionName: "my-function",
        Payload: JSON.stringify({ hello: "world" })
    })
)
.then(console.log)
.catch(console.log)

Testing

Lambda Functions

A minimal example of a JavaScript Lambda function can be found in tests/my-function/index.js

Invoking Lambda Functions

A minimal example of a JavaScript Lambda invoking can be found in tests/invoke-test.ts. To test run the following command:

npm run test:invoke