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Header category

Conditional Requests & Concurrency

Headers that make a request conditional on the state of a resource — the difference between a safe update and a lost one.

13 headers
368 provider declarations
HeaderProvidersStatus
ETag 125 permanent regulated
If-None-Match 76 permanent
If-Match 76 permanent regulated
If-Modified-Since 52 permanent
Last-Modified 29 permanent
If-Unmodified-Since 10 permanent
Schedule-Tag permanent
OData-Isolation permanent
Isolation provisional
If-Schedule-Tag-Match permanent
If-Range permanent
If permanent
Set-Txn permanent

All categories

Authentication Authorization & Scope Caching Conditional Requests & Concurrency Content Negotiation Representation Metadata Connection & Transport CORS Security Policy Privacy & Consent Rate Limiting & Quota Tracing & Correlation Idempotency & Reliability Versioning & Lifecycle Integrity & Signing Async & Long-Running Cost & Metering Agent & Bot Identity