Class PreconditionFailedError
- Namespace
- Trellis
- Assembly
- Trellis.Results.dll
Represents a precondition failure per RFC 9110 §13.1.1.
The server will not perform the request because a condition in the request headers
(e.g., If-Match, If-None-Match) evaluated to false.
Maps to HTTP 412 Precondition Failed.
public sealed class PreconditionFailedError : Error, IEquatable<Error>- Inheritance
-
PreconditionFailedError
- Implements
- Inherited Members
- Extension Methods
Examples
Error.PreconditionFailed("Resource has been modified. Please reload and retry.")
Error.PreconditionFailed("ETag mismatch — expected \"abc123\" but resource has \"def456\"")Remarks
Common scenarios include:
- If-Match ETag mismatch — the resource has been modified since the client last retrieved it
- If-None-Match failure on non-safe methods — the resource already exists
- Optimistic concurrency failure when the client provides a stale ETag
This is distinct from ConflictError (409), which indicates a state-based conflict
without a client-supplied precondition (e.g., duplicate key, FK violation).
PreconditionFailedError specifically signals that a conditional header was present and
the condition was not met.
Constructors
PreconditionFailedError(string, string, string?)
Initializes a new instance of the PreconditionFailedError class.
public PreconditionFailedError(string detail, string code, string? instance = null)