Mastering AWS Amplify CLI: A Comprehensive Guide with Hands-On Examples

AWS Amplify is a powerful set of tools and services designed to help developers build full-stack applications quickly. The Amplify CLI is the backbone of this framework, enabling developers to configure and manage cloud resources efficiently.

In this guide, we’ll deep dive into each Amplify CLI command, understanding how they work with hands-on examples.

1. Introduction to Amplify CLI

Amplify CLI is a command-line tool that interacts with AWS services, helping developers initialize, configure, and manage Amplify projects. It is essential for setting up authentication, APIs, hosting, and other backend functionalities.

2. Installing & Setting Up Amplify CLI

Before using Amplify CLI, install it globally using npm:

npm install -g @aws-amplify/cli

After installation, configure AWS credentials:

amplify configure

This command sets up Amplify with your AWS account.

3. Core Commands Overview

Below are the most frequently used Amplify CLI commands:

4. Detailed Explanation of Each Command

a. amplify init – Initialize a Project

This command sets up your Amplify project within your directory.

amplify init

• It prompts you for a project name and environment (dev/staging/prod).

• Allows you to choose a backend provider.

b. amplify add auth – Authentication Setup

To add authentication using AWS Cognito:

amplify add auth

You will get options like user sign-in, multi-factor authentication (MFA), and more.

c. amplify add api – API Integration

Add an API to your project:

amplify add api

• Choose between GraphQL and REST APIs.

• Configure permissions for accessing the API.

d. amplify push – Deploy Changes

Once you’ve made changes to your project, deploy them to AWS using:

amplify push

It uploads and provisions cloud resources.

5. Examples & Hands-On Walkthrough

Example 1: Building an Authentication System

1. Initialize a project: amplify init

2. Add authentication: amplify add auth

3. Deploy your authentication setup: amplify push

4. Integrate Amplify’s authentication module into your React project:

import { Auth } from 'aws-amplify';

const signIn = async () => {
  try {
    const user = await Auth.signIn('username', 'password');
    console.log('Logged in:', user);
  } catch (error) {
    console.error('Error signing in', error);
  }
};

Example 2: Setting Up a GraphQL API

1. Initialize a project: amplify init

2. Add a GraphQL API: amplify add api

3. Define your schema inside schema.graphql:

type Todo @model {
  id: ID!
  name: String!
  description: String
}

4. Push the API: amplify push

5. Use AWS AppSync to make GraphQL queries.

6. Common Troubleshooting & Best Practices

• Use amplify status to check the state of your backend resources before pushing updates.

• Always test configurations locally before deploying.

• Use amplify remove <feature> if you need to delete services like authentication or API from the project.

Here’s a more extensive list of AWS Amplify CLI commands for easy reference:

Of course! Here are hands-on examples for each Amplify CLI command listed earlier. 🚀

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1. amplify init – Initialize an Amplify Project

This command initializes a new Amplify project in your directory.

amplify init

Steps:

• Enter project name.

• Choose your framework (React, Angular, Vue, etc.).

• Select a backend environment (dev/staging/prod).

• Connect to AWS account.

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2. amplify configure – Configure AWS Credentials

Set up AWS credentials for Amplify.

amplify configure

Steps:

• Opens AWS Console to create access keys.

• Set up a default AWS profile.

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3. amplify add auth – Add Authentication

Adds authentication using AWS Cognito.

amplify add auth

Example:
Enable email and password authentication:

? Do you want to use default authentication settings? Yes
? Allow unauthenticated users? No
? Multi-factor authentication? Optional

After pushing changes (amplify push), integrate authentication in React:

import { Auth } from 'aws-amplify';

async function signUp(username, password, email) {
  try {
    await Auth.signUp({
      username,
      password,
      attributes: { email },
    });
    console.log('User signed up successfully!');
  } catch (error) {
    console.error('Sign-up error:', error);
  }
}

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4. amplify add api – Create an API

Adds a GraphQL or REST API to your project.

amplify add api

Example:
Set up a GraphQL API:

type Todo @model {
  id: ID!
  name: String!
  description: String
}

Query example using Amplify API module:

import { API, graphqlOperation } from 'aws-amplify';
import { listTodos } from './graphql/queries';

async function fetchTodos() {
  try {
    const todoData = await API.graphql(graphqlOperation(listTodos));
    console.log(todoData);
  } catch (error) {
    console.error('Error fetching todos:', error);
  }
}

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5. amplify add storage – Add an S3 Storage Bucket

Enables file storage using AWS S3.

amplify add storage

Example:
Upload a file in React:

import { Storage } from 'aws-amplify';

async function uploadFile(file) {
  try {
    await Storage.put(file.name, file, { contentType: file.type });
    console.log('File uploaded successfully!');
  } catch (error) {
    console.error('Upload error:', error);
  }
}

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6. amplify add function – Add a Lambda Function

Creates a Lambda function for backend processing.

amplify add function

Example:
Define your function in index.js:

exports.handler = async (event) => {
  console.log('Event received:', event);
  return { statusCode: 200, body: JSON.stringify('Hello from Lambda!') };
};

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7. amplify add notifications – Enable AWS SNS Notifications

Adds push notifications or SMS alerts.

amplify add notifications

Example:
Send an SMS notification using SNS:

import { Notifications } from 'aws-amplify';

async function sendSMS() {
  try {
    await Notifications.SMS.send({
      phoneNumber: '+911234567890',
      message: 'Welcome to AWS Amplify!',
    });
  } catch (error) {
    console.error('SMS Error:', error);
  }
}

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8. amplify push – Deploy Changes to AWS

Push all local changes to the AWS cloud.

amplify push

This provisions backend resources based on the project configuration.

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9. amplify status – Check Resource Status

Displays the current state of Amplify resources.

amplify status

Example output:

| Category  | Resource | Status  | Provider |
|-----------|---------|---------|----------|
| Auth      | Cognito | Created | AWS      |
| API       | GraphQL | Updated | AWS      |
| Storage   | S3      | Created | AWS      |

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10. amplify hosting configure – Set Up Hosting

Configures Amplify Hosting for your project.

amplify hosting configure

Steps:

• Choose static or dynamic hosting (S3, CloudFront).

• Set deployment method (manual or CI/CD).

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11. amplify delete – Remove an Amplify Project

Deletes an entire Amplify project and associated AWS resources.

amplify delete

⚠️ Warning: Use this with caution, as it cannot be undone.

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In industry settings, developers working with AWS Amplify often rely on certain commands for CI/CD pipelines, multi-environment management, and advanced debugging.

Here are some frequently used commands in enterprise-grade projects:

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1. amplify env list – List All Environments

This command is used to check available environments in your Amplify project.

amplify env list

Example output:

| Env Name | Provider | Status  |
|----------|---------|---------|
| dev      | AWS     | Active  |
| staging  | AWS     | Idle    |
| prod     | AWS     | Active  |

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2. amplify env checkout <env> – Switch Environments

Used to switch between different environments (dev, staging, prod).

amplify env checkout staging

Developers use this when working on multiple teams with separate environments.

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3. amplify override auth – Customize Authentication

This allows custom overrides for Cognito authentication settings.

amplify override auth

For example, modify Cognito attributes in override.ts:

import * as cognito from '@aws-cdk/aws-cognito';

export function override(resources) {
  resources.userPool.passwordPolicy = {
    minLength: 10,
    requireNumbers: true,
    requireUppercase: true,
  };
}

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4. amplify api gql-compile – Compile GraphQL API

Used to verify and compile GraphQL schemas locally before deploying.

amplify api gql-compile

Helps developers catch schema errors before deploying.

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5. amplify mock api – Local API Mocking

Allows local testing for GraphQL or REST APIs before deployment.

amplify mock api

Developers use this command to test API endpoints without interacting with AWS AppSync.

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6. amplify api migrate – Migrate API Versions

Used when upgrading GraphQL APIs with schema changes.

amplify api migrate

Example output:

✔ GraphQL schema changes detected.
✔ Migrating to version v2...
✔ Update successful!

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7. amplify hosting publish – Publish Static Website

Directly deploy frontend assets (React, Angular, Vue) with one command.

amplify hosting publish

Example output:

✔ Website deployed at https://myapp.amplifyapp.com

Popular in production-ready deployments.

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8. amplify function build – Build Lambda Functions

Used to compile & test AWS Lambda functions locally.

amplify function build

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9. amplify console – Open Amplify Console

Opens the AWS Amplify admin dashboard.

amplify console

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10. amplify delete – Cleanup Project

Completely removes all Amplify resources from AWS.

amplify delete

⚠️ Warning: Used rarely, but necessary when shutting down projects.

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