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API Design cors critical

CORS Patterns

Configure Cross-Origin Resource Sharing correctly for secure API access.

Difficulty
intermediate
Read time
1 min read
Version
v1.0.0
Confidence
established
Last updated

Quick Reference

CORS: Never use Access-Control-Allow-Origin: * with credentials. Whitelist specific origins. Handle preflight (OPTIONS) requests. Set appropriate Access-Control-Max-Age. Include only needed headers in Access-Control-Expose-Headers. Validate Origin header server-side.

Use When

  • Cross-origin API requests
  • Frontend on different domain
  • Third-party integrations
  • Microservices

Skip When

  • Same-origin requests
  • Server-to-server calls
  • Mobile native apps

CORS Patterns

Configure Cross-Origin Resource Sharing correctly for secure API access.

Tags

cors security api headers preflight

Discussion