Angular and AWS Amplify: Building Serverless Apps

This tutorial will guide you through the process of building serverless apps using Angular and AWS Amplify. We will start by setting up the development environment, then move on to building the frontend and backend of our application. Finally, we will learn how to deploy and test our app. By the end of this tutorial, you will have a clear understanding of how to leverage the power of Angular and AWS Amplify to build serverless applications.

Introduction

What is Angular?

Angular is a popular JavaScript framework for building web applications. It provides a structured way to build dynamic, single-page applications by using components, modules, and services. Angular follows the Model-View-Controller (MVC) architectural pattern and offers a wide range of features such as data binding, dependency injection, and routing.

What is AWS Amplify?

AWS Amplify is a set of libraries, tools, and services provided by Amazon Web Services (AWS) that simplifies the process of building cloud-based applications. It offers features such as authentication, storage, and GraphQL APIs, allowing developers to focus on building their applications rather than managing the underlying infrastructure.

Why build serverless apps?

Serverless architecture allows developers to build and run applications without worrying about the underlying infrastructure. With serverless, you don't have to manage servers, scale your application, or worry about security patches. AWS Amplify provides a serverless backend infrastructure, making it easy to build scalable and secure applications.

Setting up the Development Environment

To get started with Angular and AWS Amplify, we need to set up our development environment. Follow the steps below to install the required tools and configure AWS Amplify.

Installing Angular CLI

Angular CLI is a command-line interface tool that helps with creating, building, and testing Angular applications. To install Angular CLI, open your terminal and run the following command:

npm install -g @angular/cli

This will install Angular CLI globally on your machine.

Creating a new Angular project

Now that Angular CLI is installed, let's create a new Angular project. Open your terminal and navigate to the directory where you want to create your project. Run the following command to create a new Angular project:

ng new my-app

This will create a new directory called my-app with a basic Angular project structure.

Installing AWS Amplify CLI

Next, we need to install the AWS Amplify CLI, which is a command-line tool for configuring and managing AWS Amplify resources. Run the following command to install the AWS Amplify CLI:

npm install -g @aws-amplify/cli

This will install the AWS Amplify CLI globally on your machine.

Configuring AWS Amplify

With the AWS Amplify CLI installed, we can now configure it to work with our AWS account. Run the following command to configure AWS Amplify:

amplify configure

Follow the prompts to sign in to your AWS account and configure the AWS Amplify CLI.

Building the Frontend

Now that our development environment is set up, let's start building the frontend of our application using Angular.

Creating components

Angular uses components to build the user interface of an application. Components are reusable and independent units of code that encapsulate the HTML, CSS, and TypeScript code required to render a part of the user interface. Run the following command to create a new component:

ng generate component my-component

This will create a new directory called my-component with the necessary files for the component.

Implementing routing

Routing allows us to navigate between different views in our application. To implement routing in our Angular app, we need to define routes and configure the router module. Open the app-routing.module.ts file and add the following code:

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { MyComponentComponent } from './my-component/my-component.component';

const routes: Routes = [
  { path: '', component: MyComponentComponent }
];

@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})
export class AppRoutingModule { }

This code defines a route for our MyComponentComponent and sets it as the default route. Now, open the app.component.html file and add the following code:

<router-outlet></router-outlet>

This code tells Angular to render the component associated with the current route.

Integrating with AWS Amplify

To integrate our Angular app with AWS Amplify, we need to install the AWS Amplify libraries and configure them. Run the following command to install the AWS Amplify libraries:

npm install aws-amplify @aws-amplify/ui-angular

Now, open the main.ts file and add the following code:

import { enableProdMode } from '@angular/core';
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app/app.module';
import { environment } from './environments/environment';
import Amplify from 'aws-amplify';
import awsconfig from './aws-exports';

Amplify.configure(awsconfig);

if (environment.production) {
  enableProdMode();
}

platformBrowserDynamic().bootstrapModule(AppModule)
  .catch(err => console.error(err));

This code configures AWS Amplify with the settings defined in the aws-exports.js file.

Building the Backend

With the frontend of our application built, let's move on to building the backend using AWS Amplify.

Defining serverless functions

Serverless functions are small pieces of code that run in the cloud and respond to events. They can be used to perform tasks such as processing data, sending emails, or interacting with external services. To define a serverless function, create a new directory called functions in the root of your project. Inside the functions directory, create a new file called myFunction.js and add the following code:

exports.handler = async (event) => {
  // Your code here
};

This code defines a basic serverless function.

Setting up API endpoints

To set up API endpoints for our serverless functions, open the amplify/backend/api/myapi/schema.graphql file and add the following code:

type Query {
  getMyData: String!
}

type Mutation {
  createMyData(data: String!): String!
}

This code defines a getMyData query and a createMyData mutation.

Managing data with AWS Amplify

AWS Amplify provides a powerful data management feature called Amplify DataStore. It allows us to store, retrieve, and query data in the cloud. To use Amplify DataStore, open the app.module.ts file and add the following code:

import Amplify from 'aws-amplify';
import awsconfig from '../aws-exports';
import { DataStore } from '@aws-amplify/datastore';
import { MyData } from './models';

Amplify.configure(awsconfig);
DataStore.configure(awsconfig);

DataStore.start();

DataStore.observe(MyData).subscribe(() => {
  // DataStore changes
});

This code configures Amplify DataStore and sets up a subscription to observe changes in the MyData model.

Deploying the Application

Now that our application is built, let's deploy it to AWS Amplify.

Building the production bundle

Before we can deploy our app, we need to build the production bundle. Run the following command to build the production bundle:

ng build --prod

This will create a dist directory with the production-ready files.

Configuring AWS Amplify hosting

To configure AWS Amplify hosting, open the amplify.yml file and add the following code:

version: 1
frontend:
  phases:
    preBuild:
      commands:
        - npm ci
    build:
      commands:
        - ng build --prod
  artifacts:
    baseDirectory: dist/my-app
    files:
      - '**/*'
  cache:
    paths:
      - node_modules/**/*

This code configures the build and deployment process for our app.

Deploying the app

To deploy our app to AWS Amplify, run the following command:

amplify publish

This will deploy our app to the configured AWS Amplify environment.

Testing and Debugging

Testing and debugging are crucial parts of the development process. Let's explore how to test and debug our Angular and AWS Amplify app.

Unit testing Angular components

Angular provides a built-in testing framework called @angular/cli to help with unit testing. To test an Angular component, create a new file called my-component.component.spec.ts and add the following code:

import { ComponentFixture, TestBed } from '@angular/core/testing';
import { MyComponentComponent } from './my-component.component';

describe('MyComponentComponent', () => {
  let component: MyComponentComponent;
  let fixture: ComponentFixture<MyComponentComponent>;

  beforeEach(async () => {
    await TestBed.configureTestingModule({
      declarations: [ MyComponentComponent ]
    })
    .compileComponents();
  });

  beforeEach(() => {
    fixture = TestBed.createComponent(MyComponentComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });

  it('should create', () => {
    expect(component).toBeTruthy();
  });
});

This code sets up a basic unit test for our MyComponentComponent.

Testing serverless functions

To test serverless functions, we can use the AWS Amplify CLI's mock command. Run the following command to start mocking the serverless functions:

amplify mock function myFunction

This will start a local server that emulates the serverless function.

Debugging serverless apps

To debug serverless apps, we can use the AWS Amplify CLI's logs command. Run the following command to view the logs of our serverless functions:

amplify logs

This will display the logs generated by our serverless functions.

Conclusion

In this tutorial, we have learned how to build serverless apps using Angular and AWS Amplify. We started by setting up the development environment, then moved on to building the frontend and backend of our application. Finally, we learned how to deploy and test our app. By leveraging the power of Angular and AWS Amplify, we can easily build scalable and secure serverless applications.