gRPC 9 FAILED_PRECONDITION vs 12 UNIMPLEMENTED
Both gRPC 9 (FAILED_PRECONDITION) and 12 (UNIMPLEMENTED) belong to the gRPC Status Codes category. 9 indicates that the operation was rejected because the system is not in a state required for the operation's execution. For example, deleting a non-empty directory. Meanwhile, 12 means that the operation is not implemented or is not supported/enabled in this service.
描述
The operation was rejected because the system is not in a state required for the operation's execution. For example, deleting a non-empty directory.
何时出现
The request is valid on its own, but the system's current state doesn't allow it — like trying to delete a non-empty directory or update a resource that has been modified concurrently.
如何修复
Bring the system into the required state before retrying. For example, empty the directory first, or re-read the resource to get the latest version before updating.
描述
The operation is not implemented or is not supported/enabled in this service.
何时出现
The client called an RPC method that the server does not implement. This often happens when the client uses a newer proto definition than the server supports.
如何修复
Verify the server version supports the method you're calling. Update the server to implement the missing method, or use an alternative endpoint.
主要区别
gRPC 9: The operation was rejected because the system is not in a state required for the operation's execution. For example, deleting a non-empty directory.
gRPC 12: The operation is not implemented or is not supported/enabled in this service.
You encounter 9 when the request is valid on its own, but the system's current state doesn't allow it — like trying to delete a non-empty directory or update a resource that has been modified concurrently.
You encounter 12 when the client called an RPC method that the server does not implement. This often happens when the client uses a newer proto definition than the server supports.
何时使用哪个
For 9 (FAILED_PRECONDITION): Bring the system into the required state before retrying. For example, empty the directory first, or re-read the resource to get the latest version before updating. For 12 (UNIMPLEMENTED): Verify the server version supports the method you're calling. Update the server to implement the missing method, or use an alternative endpoint.