Wiki Article · Cinematic

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Overview

Copyright (c) A|iens. All rights reserved. — Quick Facts

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Property: Detail

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Concept Name: Preflight Request

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Also Known As: CORS Preflight, OPTIONS Preflight,…

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Category: Web Communication / HTTP Protocol

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Infobox

📚 | Property | Detail | |---|---| | Concept Name | Preflight Request | | Also Known As |…

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Same-Origin Policy — Background

💡 Same-Origin Policy (SOP) web security ka sabse fundamental rule hai. Yeh rule kehta hai…

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CORS — The Mechanism Behind Preflight

🎯 CORS (Cross-Origin Resource Sharing) ek HTTP-header-based mechanism hai jo server ko…

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When Does Preflight Trigger

⭐ Har cross-origin request preflight nahi trigger karti. Browser pehle check karta hai ke…

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Preflight Request Flow — Visual

🔑 Neeche ka Mermaid sequence diagram preflight request ka complete flow dikhata hai:…

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Preflight Request and Response Headers

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Access-Control-Allow-Origin: * aur…

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Access-Control-Allow-Methods me…

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Missing headers = preflight fail.…

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Preflight Response Caching

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Chrome: Maximum cache ~2 hours…

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Firefox: Maximum ~24 hours (86400…

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Safari: Behavior vary karta hai,…

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Simple Requests — No Preflight Needed

🚀 Simple requests directly server ko jaati hain bina preflight ke. Browser sirf response me…

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Common Preflight Scenarios

📚 Scenario 1: SPA calling REST API Frontend https://app.com se backend…

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Server-Side CORS Configuration

💡 Server ko preflight requests handle karne ke liye OPTIONS method properly respond karna…

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Preflight Failures and Debugging

🎯 | Failure Type | Error Message (Console) | Cause | Fix | |---|---|---|---| | Missing…

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Performance Optimization

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Frontend server (Nginx/Apache) par…

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Ab browser ke liye sab requests…

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CORS completely eliminated — koi…

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Security Considerations

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Preflight CSRF protection ka…

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CSRF tokens, SameSite cookies, aur…

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Cookies aur auth headers…

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Server ko…

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Historical Context and Evolution

✨ | Year | Event | Significance | |---|---|---| | 1995 | Netscape introduces Same-Origin…

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Preflight in Modern Frameworks and APIs

🌟 Modern web frameworks me CORS/preflight handling ab significantly simplified ho chuka hai…

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Common Mistakes

🚀 1. CORS error ko server error samajhna: CORS error browser-side enforcement hai. Server…

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Best Practices

📚 1. Specific origins whitelist karo: Production me * avoid karo. Server me allowed origins…

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Glossary

💡 | Term | Definition | |---|---| | Preflight Request | Browser dwara automatic OPTIONS…

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Disclaimer

🎯 Yeh article educational purposes ke liye hai aur Aliens Wiki HIEN collection ka hissa…

Diagram

Visual Flow

📊 Diagram visualization — details in narration

Quiz — Question 1

Quick Quiz

Quiz — Question 2

Complete! 🎉

Aliens Wiki · HIEN · Cinematic Knowledge

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