Twig is a powerful and flexible templating engine for PHP, commonly used in Symfony but also in other PHP projects. It helps separate logic from presentation and offers many useful features for frontend development.
{{ }}
)Twig uses double curly braces to output variables:
<p>Hello, {{ name }}!</p>
→ If name = "Max"
, the output will be:
"Hello, Max!"
{% %}
)Twig supports if-else statements, loops, and other control structures.
{% if user.isAdmin %}
<p>Welcome, Admin!</p>
{% else %}
<p>Welcome, User!</p>
{% endif %}
Loops (for
)
<ul>
{% for user in users %}
<li>{{ user.name }}</li>
{% endfor %}
</ul>
Twig supports "Base Layouts", similar to Laravel's Blade.
base.html.twig
)<!DOCTYPE html>
<html>
<head>
<title>{% block title %}My Page{% endblock %}</title>
</head>
<body>
<header>{% block header %}Default Header{% endblock %}</header>
<main>{% block content %}{% endblock %}</main>
</body>
</html>
Child Template (page.html.twig
)
{% extends 'base.html.twig' %}
{% block title %}Homepage{% endblock %}
{% block content %}
<p>Welcome to my website!</p>
{% endblock %}
→ The blocks override the default content from the base template.
You can include reusable components like a navbar or footer:
{% include 'partials/navbar.html.twig' %}
Twig provides many filters to format content:
Filter | Beispiel | Ausgabe |
---|---|---|
upper |
`{{ "text" | upper }}` |
lower |
`{{ "TEXT" | lower }}` |
length |
`{{ "Hallo" | length }}` |
date |
`{{ "now" | date("d.m.Y") }}` |
Twig automatically escapes HTML to prevent XSS attacks:
{{ "<script>alert('XSS');</script>" }}
→ Outputs: <script>alert('XSS');</script>
To output raw HTML, use |raw
:
{{ "<strong>Bold</strong>"|raw }}
The View is the presentation layer in the MVC architecture. It is responsible for displaying data from the Model in a user-friendly format.
✅ Displaying Data: Shows information from the Model (e.g., a list of blog posts).
✅ Reacting to User Interactions: Accepts user input and sends it to the Controller.
✅ Formatting & Layout: Structures content using HTML, CSS, or templating engines (e.g., Laravel Blade or Twig).
✅ Avoiding Business Logic: Contains only presentation logic, not data processing.
<!-- resources/views/blog/index.blade.php -->
@extends('layouts.app')
@section('content')
<h1>Blog Posts</h1>
@foreach ($posts as $post)
<div>
<h2>{{ $post->title }}</h2>
<p>{{ $post->content }}</p>
</div>
@endforeach
@endsection
🔹 @foreach
: Loops through the list of blog posts and displays them.
🔹 {{ $post->title }}
: Outputs the title of the blog post.
✔ The View is responsible for presentation but does not process data.
✔ It ensures a clear separation between logic and display.
✔ Using templates or frontend technologies (e.g., Vue.js, React), the View can be dynamically rendered.
The Model is the data and logic layer in the MVC architecture. It manages the application's data and ensures that it is correctly stored, retrieved, and processed.
✅ Data Management: Stores and handles data, often in a database.
✅ Business Logic: Contains rules and calculations (e.g., discount calculation for orders).
✅ Data Validation: Checks if input is correct (e.g., if an email address is valid).
✅ Database Communication: Performs CRUD operations (Create, Read, Update, Delete).
class BlogPost extends Model {
protected $fillable = ['title', 'content']; // Erlaubte Felder für Massenverarbeitung
// Beziehung: Ein Blogpost gehört zu einem Benutzer
public function user() {
return $this->belongsTo(User::class);
}
}
🔹 fillable
: Specifies which fields can be saved.
🔹 belongsTo(User::class)
: Indicates that each blog post belongs to a user.
✔ The Model handles all data and business logic of the application.
✔ It ensures a clear separation between data and presentation.
✔ Changes to the data structure only need to be made in the Model, not throughout the entire application.
A Controller is a key component in the Model-View-Controller (MVC) architecture. It acts as an intermediary between the user interface (View) and the business logic or data (Model).
Handling User Input
Processing the Request
Interacting with the Model
Updating the View
Suppose a user wants to create a new blog post:
class BlogController extends Controller {
public function store(Request $request) {
// Validierung der Benutzereingabe
$request->validate([
'title' => 'required|max:255',
'content' => 'required',
]);
// Neues Blog-Post-Model erstellen und speichern
BlogPost::create([
'title' => $request->input('title'),
'content' => $request->input('content'),
]);
// Weiterleitung zur Blog-Übersicht
return redirect()->route('blog.index')->with('success', 'Post erstellt!');
}
}
✔ A controller manages the flow of an application and separates business logic from presentation.
✔ It ensures clean code structure, as each component (Model, View, Controller) has a specific responsibility.
✔ Modern frameworks like Laravel, Django, or ASP.NET often include built-in routing mechanisms that automatically direct requests to the appropriate controllers.
Model-View-Controller (MVC) is a software architecture pattern that divides an application into three main components:
✔ Better maintainability through a clear separation of concerns.
✔ Reusability of components.
✔ Easy testability since logic is separated from the interface.
✔ Flexibility, as different views can be used for the same model.
MVC is widely used in web and desktop applications, including:
The Catalyst Framework is a flexible and powerful web framework for Perl. It enables the development of scalable and maintainable web applications and follows the Model-View-Controller (MVC) design pattern.
✅ MVC Architecture – Clear separation of business logic, presentation, and data management
✅ Flexibility – Supports various templating systems and ORM solutions like DBIx::Class
✅ Extensibility – Many plugins and modules available
✅ Asynchronous Capabilities – Can be integrated with event-driven architectures
✅ REST APIs & WebSockets – Support for modern web technologies
Perl is a powerful, flexible, and versatile programming language, originally designed for text processing and system administration. The name stands for "Practical Extraction and Report Language", though this was a retroactive acronym.
✅ Dynamic & flexible – Perl is not strictly typed and supports multiple programming paradigms.
✅ Strong in text processing – Ideal for regular expressions, data manipulation, and parsing.
✅ Cross-platform – Runs on Windows, Linux, macOS, and more.
✅ Large community & CPAN – The Comprehensive Perl Archive Network (CPAN) offers thousands of ready-to-use modules and extensions.
✅ Use cases – Commonly used for web development (CGI scripts), system administration, network programming, and data analysis.
#!/usr/bin/perl
use strict;
use warnings;
print "Hello, World!\n";
Entity headers are HTTP headers that provide information about the body of a message. They can appear in both requests and responses, describing properties of the content such as type, length, encoding, or last modification date.
1.
Content-Type
Content-Type: application/json; charset=UTF-8
2.
Content-Length
Content-Length: 1024
3.
Content-Encoding
Content-Encoding: gzip
4. Content-Language
Content-Language: de-DE
5. Cache-Location
Content-Location: /files/document.pdf
6. Last-Modified
Last-Modified: Tue, 30 Jan 2025 14:20:00 GMT
7. ETag
ETag: "abc123xyz"
8. Expires
Expires: Fri, 02 Feb 2025 12:00:00 GMT
9. Allow
Allow: GET, POST, HEAD
10. Refresh
(Not standardized but often used)
Refresh: 10; url=https://example.com
These headers help describe the content of an HTTP message, optimize caching strategies, and ensure correct rendering.
Response headers are HTTP headers sent from the server to the client. They contain information about the server’s response, such as status codes, content types, security policies, or caching rules.
1. Server
Server: Apache/2.4.41 (Ubuntu)
2. Date
Date: Wed, 31 Jan 2025 12:34:56 GMT
3. Content-Type
Content-Type: text/html; charset=UTF-8
4. Content-Length
Content-Length: 3456
5. Cache-Control
Cache-Control: max-age=3600, must-revalidate
6. Set-Cookie
Set-Cookie: sessionId=abc123; Path=/; Secure; HttpOnly
7. ETag
ETag: "5d8c72a5f8d9f"
8. Location
Location: https://www.new-url.com/
9. Access-Control-Allow-Origin
Access-Control-Allow-Origin: *
10. Strict-Transport-Security
(HSTS)
Strict-Transport-Security: max-age=31536000; includeSubDomains
Response headers help the client interpret the received response correctly, enforce security measures, and optimize caching strategies.
Request headers are HTTP headers sent by a client (e.g., a web browser or API request) to the server, providing additional information about the request, the client, or the desired content.
1. Host
Host: www.example.com
2. User-Agent
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64)
3. Accept
Accept: text/html, application/json
4. Accept-Language
Accept-Language: de-DE, en-US
5. Accept-Encoding
Accept-Encoding: gzip, deflate, br
6. Referer
Referer: https://www.google.com/
7. Authorization
Authorization: Basic dXNlcm5hbWU6cGFzc3dvcmQ=
8. Cookie
Cookie: sessionId=abc123; theme=dark
9. Content-Type
(for POST/PUT-Anfragen)
Content-Type: application/json
10. Origin
Origin: https://www.example.com
These headers help the server understand the request and respond accordingly by providing details about the client, preferred content, and security aspects.