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428
Precondition Required
The origin server requires the request to be conditional.
Common Causes
- •Missing If-Match header
- •Optimistic concurrency required
- •Version control needed
Fix Solutions
Add precondition headers
Include If-Match or If-Unmodified-Since headers.
Code Examples
# Add precondition header
curl -H 'If-Match: "etag-value"' -X PUT https://example.com/resource