Amplify

Introduction

Amplify is a JavaScript-based development framework with libraries, UI components, and a standard CLI interface for building and deploying web and mobile applications. With Amplify, developers can build and host static websites, single-page applications, and full-stack serverless web applications using an abstraction layer over popular AWS services like DynamoDB, Cognito, AppSync, Lambda, S3, and more.

LocalStack allows you to use the Amplify APIs to build and test their Amplify applications locally. The supported APIs are available on our API coverage page, which provides information on the extent of Amplify’s integration with LocalStack.

Amplify LocalStack Plugin

Amplify LocalStack Plugin allows the amplify CLI tool to create resources on your local machine instead of AWS. It achieves this by redirecting any requests to AWS to a LocalStack container running locally on your machine.

Installation

To install the Amplify LocalStack Plugin, install the amplify-localstack package from the npm registry and add the plugin to your Amplify setup:

$ npm install -g amplify-localstack
$ amplify plugin add amplify-localstack

Configuration

You can configure the following environment variables to customize LocalStack’s behaviour:

• EDGE_PORT: The port number under which the LocalStack edge service is accessible. The default value is 4566.
• LOCALSTACK_HOSTNAME: It specifies the target host under which the LocalStack edge service is accessible. The default value is localhost.localstack.cloud.
• LOCALSTACK_ENDPOINT: It allows you to set a custom endpoint directly. If set, it overrides the values set for EDGE_PORT and LOCALSTACK_HOSTNAME. The default value is https://localhost.localstack.cloud:4566.

Usage

After installing the plugin, you can deploy your resources to LocalStack using the amplify init or amplify push commands. The console will prompt you to select whether to deploy to LocalStack or AWS.

You can also add the parameter --use-localstack true to your commands to avoid being prompted and automatically use LocalStack. Here is an example:

$ amplify init --use-localstack true
$ amplify add api
$ amplify push --use-localstack true