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PRECONDITION_REQUIRED — PATCH request missing required If-Match header

cyoda-go version 0.8.2

errors.PRECONDITION_REQUIRED

Section titled “errors.PRECONDITION_REQUIRED”

NAME

Section titled “NAME”

PRECONDITION_REQUIRED — a PATCH request was submitted without an If-Match header, which is mandatory for patch operations.

SYNOPSIS

Section titled “SYNOPSIS”

HTTP: 428 Precondition Required. Retryable: no.

DESCRIPTION

Section titled “DESCRIPTION”

PATCH applies a merge patch to the entity’s stored state rather than replacing it wholesale. Because the patch is applied relative to the current stored data, cyoda-go requires the caller to state a precondition explicitly via If-Match. Omitting the header entirely is rejected.

This behaviour is specific to PATCH. A PUT without If-Match is treated as an unconditional replace and is accepted.

Not retryable as-is — the same request without an If-Match header produces the same error.

RECOVERY

Section titled “RECOVERY”

Add an If-Match header to the PATCH request. Two modes are supported:

  • Conditional patch — supply the transactionId obtained from your most recent GET of the entity as the If-Match value. The patch is applied only if the entity has not changed since that read; a 412 ENTITY_MODIFIED is returned if another writer has committed in the meantime.
  • Unconditional patch (last-writer-wins) — supply If-Match: * to explicitly accept that the patch will be applied to whatever the current stored state is, without a version check.

Choose the conditional form when you need to detect concurrent modifications; choose * when you intentionally want last-writer-wins semantics and have already decided the patch is safe to apply regardless of concurrent changes.

SEE ALSO

Section titled “SEE ALSO”
  • errors
  • errors.ENTITY_MODIFIED
  • errors.BAD_REQUEST

See also

Section titled “See also”
  • cyoda help errors — Every error response from the Cyoda REST API carries a structured errorCode in the properties object. Multiple codes may share the same HTTP status. Programmatic handling keys on errorCode, not HTTP status.
  • cyoda help errors ENTITY_MODIFIED — When an entity update request carries an If-Match header, the server requires the supplied transaction ID to equal the entity’s current meta.transactionId. A mismatch means another writer has updated the entity since the caller’s last read. The optimistic-concurrency guard rejects the update rather than silently overwrite.
  • cyoda help errors BAD_REQUEST — Fired when the server cannot parse or structurally process the incoming request. Common triggers include invalid JSON, missing required fields, unsupported format specifiers, or mutually exclusive parameters being set simultaneously.

Raw formats

Section titled “Raw formats”