go data_error ai_generated true

rpc error: code = FailedPrecondition desc = resource version mismatch: expected 42, got 41

ID: go/grpc-failed-precondition

Also available as: JSON · Markdown · 中文
80%Fix Rate
83%Confidence
0Evidence
2024-12-02First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
1.x active — — —

Root Cause

The server rejected the operation because a precondition on the resource state was not met — typically optimistic concurrency control where the client's version/etag is stale relative to the current server state.

generic

中文

服务器拒绝了操作，因为资源状态的前置条件未满足——通常是乐观并发控制，客户端携带的版本/etag 相对于服务器当前状态已过时。

Workarounds

  1. 88% success 
    Re-fetch the latest resource, apply the mutation to the fresh copy, and retry with the new version:

for i := 0; i < 5; i++ {
    cur, err := client.Get(ctx, &pb.GetReq{Id: id})
    if err != nil { return err }
    cur.Data = newData
    _, err = client.Update(ctx, &pb.UpdateReq{Id: id, Data: newData, Version: cur.Version})
    if status.Code(err) != codes.FailedPrecondition { return err }
}
  2. 80% success 
    Use an ETag/If-Match style conditional request and surface a conflict to the caller when it persists:

if status.Code(err) == codes.FailedPrecondition {
    return ErrConflict // let the caller resolve
}

Dead Ends

Common approaches that don't work:

  1. 90% fail

    The version is still stale; the server rejects every identical attempt with the same FailedPrecondition.

  2. 70% fail

    Removing the precondition bypasses concurrency control and risks last-writer-wins data loss.