Errors and Error Handling

When a Firestore in Datastore mode request is successful, the API will return an HTTP 200 OK status code along with the requested data in the body of the response.

When a request fails, the Datastore API will return an HTTP 4xx or 5xx status code that generically identifies the failure as well as a response that provides more specific information about the error(s) that caused the failure.

The rest of this page describes the structure of an error, enumerates specific error codes, and recommends how to handle them.

The following is the structure of an error response for a JSON request:

{
  "error": {
    "code": "integer",
    "message": "string",
    "status": "string"
  }
}

The response object contains a single field error whose value contains the following elements:

Here's an example of an error response for a JSON request:

{
  "error": {
    "code": 400,
    "message": "Key path is incomplete: [Person: null]",
    "status": "INVALID_ARGUMENT"
  }
}

If a request made with a content type of application/x-protobuf results in an error, it will return a serialized google.rpc.Status message as the payload.

Error Codes

The recommended way to classify errors is inspect the value of the canonical error code (google.rpc.Code). In JSON errors, this code appears in the status field. In application/x-protobuf errors, it's in the code field.