Angular-CLI Project Serve Command: A Step-by-Step Guide to Usage and Troubleshooting

The Angular-CLI is a powerful command-line tool that helps developers create, develop, and maintain Angular applications. In this guide, we will focus on the ng serve command, which is used to build and start a local development server for your Angular application. We will cover the usage of this command, its various options, and troubleshooting common issues that you might encounter.

Table of Contents

• Prerequisites
• Serving your Angular Application
• Command Options
• Troubleshooting Common Issues
• FAQ
• Related Links

Prerequisites

Before we proceed, ensure that you have the following installed on your system:

1. Node.js (version 12 or later)
2. Angular CLI (version 8 or later)

To verify that Node.js and Angular CLI are installed correctly, run the following commands in your terminal:

node -v
ng version

These commands should display the installed versions of Node.js and Angular CLI, respectively.

Serving your Angular Application

Step 1: Create a new Angular application

If you have an existing Angular application, skip to Step 2. To create a new Angular application, open your terminal and run the following command:

ng new my-app

Replace my-app with your desired application name. This will create a new directory with the same name and set up the necessary files for your Angular application.

Step 2: Navigate to the application directory

Change to the newly created application directory by running the following command in the terminal:

cd my-app

Replace my-app with your application's name.

Step 3: Serve your application

To serve your Angular application locally, run the following command in the terminal:

ng serve

By default, the application will be served on http://localhost:4200/. Open your browser and navigate to this URL to view your application.

Command Options

The ng serve command comes with several options that you can use to customize its behavior. Some of the most commonly used options are:

• --open or -o: Automatically opens your default web browser and navigates to the application URL.
• --port or -p: Specifies the port number on which the development server will listen. For example, ng serve --port 4500 will serve the application on http://localhost:4500/.
• --prod or --configuration=production: Builds and serves the application using production settings.
• --ssl: Serves the application over HTTPS.

For a complete list of options, refer to the official Angular CLI documentation.

Troubleshooting Common Issues

Here are some common issues that you might encounter while using the ng serve command, along with their solutions:

Issue 1: Port 4200 is already in use

If the default port (4200) is already in use by another application, you will see an error message like this:

Port 4200 is already in use. Use '--port' to specify a different port.

Solution: Use the --port option to specify a different port number, as shown below:

ng serve --port 4500

Issue 2: ng serve command not found

If you see an error message like "command not found" or "ng is not recognized as an internal or external command", it usually means that Angular CLI is not installed correctly or not added to your system's PATH.

Solution: Try reinstalling the Angular CLI by running the following command:

npm install -g @angular/cli

If the issue persists, refer to the Angular CLI installation guide for more help.

FAQ

1. How do I stop the development server?

To stop the development server, press Ctrl + C in the terminal where the server is running.

2. How do I serve my application with a specific base href?

To serve your application with a specific base href, use the --base-href option, as shown below:

ng serve --base-href /my-app/

3. Can I serve multiple Angular applications simultaneously?

Yes, you can serve multiple Angular applications simultaneously by running the ng serve command in separate terminal instances and specifying different port numbers using the --port option.

4. How do I enable Hot Module Replacement (HMR) in my Angular application?

To enable Hot Module Replacement, use the --hmr option, as shown below:

ng serve --hmr

5. How do I view the application in a different browser?

By default, the --open or -o option opens the application in your default web browser. To view the application in a different browser, manually enter the application URL (e.g., http://localhost:4200/) in the desired browser's address bar.

Related Links

• Angular CLI Official Documentation
• Angular Project Setup Guide
• Angular CLI Serve Command Reference
• Hot Module Replacement in Angular

We hope this guide helps you understand the usage and troubleshooting of the Angular-CLI Project Serve Command. If you have any further questions or issues, please refer to the official Angular CLI documentation or reach out to the Angular community.