Web Development

XML CDATA Complete Guide: How to Handle Special Characters in XML

Master XML CDATA sections with practical examples. Learn when to use CDATA vs escaping, security best practices, and real-world applications for JavaScript, CSS, and HTML embedding. Understanding XML CDATA: Essential Guide to Handling Special Characters What is CDATA and Why It Matters CDATA (Character Data) creates safe zones in XML where special characters like <, >, and & can appear without escaping. It tells XML parsers: “Don’t interpret this text as markup!” ...

Understanding Preflight OPTIONS Requests: The CORS Gatekeeper

Browsers enforce the same-origin policy to prevent malicious cross-site requests. Preflight acts as a “handshake” before sensitive requests, asking: “Server, are you cool with this?” 🔥 Triggers for Preflight: Non-simple HTTP methods (PUT, DELETE, PATCH) Custom headers (e.g., X-API-Token) “Advanced” Content-Types (e.g., application/json) Credentialed requests (with cookies/auth) ✅ Simple requests (GET/POST with basic headers) skip preflight! 🔁 How Preflight Works: A 2-Step Dance sequenceDiagram Browser->>Server: OPTIONS Request (Preflight) Note left of Browser: Headers sent: 📍 Origin 📍 Access-Control-Request-Method 📍 Access-Control-Request-Headers alt Server Allows Server-->>Browser: 200 OK + CORS Headers Note right of Server: Headers returned: ✅ Access-Control-Allow-Origin ✅ Access-Control-Allow-Methods ✅ Access-Control-Allow-Headers Browser->>Server: Actual Request (e.g., DELETE) else Server Denies Server-->>Browser: CORS Error Blocked! end ⚙️ Server-Side Setup Essentials Handle OPTIONS requests correctly: ...

SQL Injection Attacks: Complete Guide to Prevention and Defense

SQL injection remains one of the most dangerous web application vulnerabilities, responsible for 33% of all web breaches in 2023. This comprehensive guide explains how these attacks work, their real-world impact, and effective defense strategies for developers and security professionals. 1. Understanding SQL Injection Attacks 1.1 What is SQL Injection? SQL injection occurs when attackers exploit improper input sanitization to inject malicious SQL code into database queries. This vulnerability allows attackers to: ...