gRPC 5 NOT_FOUND vs 9 FAILED_PRECONDITION
Both gRPC 5 (NOT_FOUND) and 9 (FAILED_PRECONDITION) belong to the gRPC Status Codes category. 5 indicates that some requested entity was not found. For example, a file or directory that the RPC was supposed to operate on does not exist. Meanwhile, 9 means 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.
설명
Some requested entity was not found. For example, a file or directory that the RPC was supposed to operate on does not exist.
이 코드를 보게 되는 경우
The resource referenced in the request doesn't exist — such as looking up a user by ID that has been deleted or never created.
해결 방법
Verify the resource identifier is correct. Ensure the resource was created before accessing it, or handle the not-found case gracefully in your client.
설명
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.
이 코드를 보게 되는 경우
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.
해결 방법
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.
주요 차이점
gRPC 5: Some requested entity was not found. For example, a file or directory that the RPC was supposed to operate on does not exist.
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.
You encounter 5 when the resource referenced in the request doesn't exist — such as looking up a user by ID that has been deleted or never created.
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.
언제 어떤 것을 사용할지
For 5 (NOT_FOUND): Verify the resource identifier is correct. Ensure the resource was created before accessing it, or handle the not-found case gracefully in your client. 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.