Lesson 19: Introduction to PHP Frameworks

PHP frameworks streamline development by providing tools, libraries, and best practices to build robust, secure, and scalable applications. This lesson introduces popular PHP frameworks, including Laravel, Symfony, and CodeIgniter, and provides a detailed guide to installing and setting up Laravel.

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19.1 Overview of PHP Frameworks

What is a PHP Framework?

• A PHP framework is a platform that provides a structured way to build PHP applications.
• Benefits:
  • Simplifies repetitive tasks like routing, authentication, and database management.
  • Encourages clean, reusable code.
  • Enhances application security and scalability.

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Popular PHP Frameworks

1. Laravel

• Tagline: “The PHP Framework for Web Artisans.”
• Features:
  • Elegant syntax and expressive ORM (Eloquent).
  • Built-in authentication and authorization.
  • Blade templating engine for views.
  • Easy database migrations.
  • Integrated task scheduling and queue system.
• Use Cases:
  • Ideal for medium to large-scale applications requiring complex features.

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2. Symfony

• Tagline: “A set of reusable PHP components and a framework for web applications.”
• Features:
  • Modular components (e.g., Symfony HTTP Foundation, Security).
  • High performance and flexibility.
  • Advanced configuration options.
  • Used as a foundation for other frameworks like Laravel.
• Use Cases:
  • Suitable for enterprise-level applications with specific requirements.

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3. CodeIgniter

• Tagline: “A powerful PHP framework with a very small footprint.”
• Features:
  • Lightweight and fast.
  • Simple and straightforward.
  • No complex configurations or dependencies.
  • Excellent for building REST APIs and small-scale applications.
• Use Cases:
  • Best for small to medium-sized projects or developers new to frameworks.

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Comparison Table

Feature	Laravel	Symfony	CodeIgniter
Learning Curve	Moderate	Steep	Easy
Scalability	High	Very High	Moderate
Performance	Moderate	High	Very High
Community Support	Large and active	Active	Moderate
Templating Engine	Blade	Twig	Basic PHP

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19.2 Installing and Setting Up Laravel

Step 1: System Requirements

Before installing Laravel, ensure your system meets the following requirements:

• PHP: Version 8.0 or higher.
• Composer: Dependency manager for PHP.
• Database: MySQL, PostgreSQL, SQLite, or SQL Server.

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Step 2: Installing Composer

1. Download and install Composer from getcomposer.org.
2. Verify installation:
   bash

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   composer --version


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Step 3: Installing Laravel

Laravel can be installed in two ways: via the Laravel Installer or Composer.

Method 1: Using Laravel Installer

1. Install the Laravel Installer:
   bash

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   composer global require laravel/installer

2. Create a new Laravel project:
   bash

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   laravel new project-name

3. Navigate to the project directory:
   bash

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   cd project-name


Method 2: Using Composer

1. Run the following command:
   bash

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   composer create-project --prefer-dist laravel/laravel project-name

2. Navigate to the project directory:
   bash

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   cd project-name


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Step 4: Setting Up the Development Environment

1. Environment Configuration:
   • Rename .env.example to .env:
     bash

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     cp .env.example .env

   • Configure database settings in the .env file:
     env

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     DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_PORT=3306
DB_DATABASE=your_database_name
DB_USERNAME=your_database_username
DB_PASSWORD=your_database_password

2. Generate Application Key:
   bash

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   php artisan key:generate

   • This command sets the APP_KEY in the .env file, which is used for encryption.

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Step 5: Running the Application

1. Start the development server:
   bash

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   php artisan serve

2. Open your browser and navigate to:
   text

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   http://localhost:8000


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Step 6: Exploring Laravel Directory Structure

• app/: Contains the core application files (models, controllers, etc.).
• routes/: Contains route definitions (web.php for web routes, api.php for API routes).
• resources/views/: Stores Blade templates for views.
• database/: Contains migration and seed files.
• public/: Entry point for the application (e.g., index.php).

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19.3 Creating a Simple Laravel Application

Example: Task Management Application

Step 1: Set Up the Database

1. Create a database tasks.
2. Update the .env file:
   env

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   DB_DATABASE=tasks


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Step 2: Create a Migration

1. Run the migration command:
   bash

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   php artisan make:migration create_tasks_table

2. Edit the migration file in database/migrations/:
   php

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   public function up()
{
Schema::create('tasks', function (Blueprint $table) {
$table->id();
$table->string('title');
$table->boolean('completed')->default(false);
$table->timestamps();
});
}

3. Run the migration:
   bash

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   php artisan migrate


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Step 3: Create a Model

1. Run the model command:
   bash

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   php artisan make:model Task


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Step 4: Create a Controller

1. Run the controller command:
   bash

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   php artisan make:controller TaskController

2. Add the following methods to TaskController:
   php

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   public function index()
{
$tasks = Task::all();
return view('tasks.index', compact('tasks'));
}public function store(Request $request)
   {
   $task = new Task();
   $task->title = $request->title;
   $task->save();

   return redirect()->back();
   }

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Step 5: Set Up Routes

Edit routes/web.php:

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Step 6: Create a Blade Template

Create a new file resources/views/tasks/index.blade.php:

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Activities and Exercises

1. Explore Laravel Features:
   • Experiment with database migrations, routes, and Blade templates.
2. Build a Simple Application:
   • Create a “Contact Manager” application with CRUD operations for contacts.
3. Experiment with Middleware:
   • Add middleware for authentication or logging requests.

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Assignment

1. Create a “Blog” application with the following features:
   • Display a list of blog posts.
   • Add new posts.
   • Edit and delete existing posts.
2. Explore the official Laravel documentation to learn about:
   • Authentication (php artisan make:auth).
   • Laravel’s built-in queue system.

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Summary

In this lesson, you learned:

1. The benefits and features of Laravel, Symfony, and CodeIgniter.
2. How to install and set up Laravel.
3. How to create a simple Laravel application.

Laravel provides a powerful foundation for building modern PHP applications. Let me know if you’d like to dive deeper into Laravel or other frameworks!