handle db errors the same way as other backend requests

pylib/anki/rsbackend.py

@@ -233,7 +233,13 @@ class RustBackend(RustBackendGenerated):
         return self._db_command(dict(kind="rollback"))
 
     def _db_command(self, input: Dict[str, Any]) -> Any:
-        return from_json_bytes(self._backend.db_command(to_json_bytes(input)))
+        try:
+            return from_json_bytes(self._backend.db_command(to_json_bytes(input)))
+        except Exception as e:
+            err_bytes = bytes(e.args[0])
+        err = pb.BackendError()
+        err.ParseFromString(err_bytes)
+        raise proto_exception_to_native(err)
 
     def translate(self, key: TRValue, **kwargs: Union[str, int, float]) -> str:
         return self.translate_string(translate_string_in(key, **kwargs))
@@ -254,7 +260,7 @@ class RustBackend(RustBackendGenerated):
             return self._backend.command(method, input_bytes)
         except Exception as e:
             err_bytes = bytes(e.args[0])
-            err = pb.BackendError()
+        err = pb.BackendError()
         err.ParseFromString(err_bytes)
         raise proto_exception_to_native(err)
 

rslib/src/backend/mod.rs

@@ -1528,6 +1528,15 @@ impl Backend {
     pub fn db_command(&self, input: &[u8]) -> Result<Vec<u8>> {
         self.with_col(|col| db_command_bytes(&col.storage, input))
     }
+
+    pub fn run_db_command_bytes(&self, input: &[u8]) -> std::result::Result<Vec<u8>, Vec<u8>> {
+        self.db_command(input).map_err(|err| {
+            let backend_err = anki_error_to_proto_error(err, &self.i18n);
+            let mut bytes = Vec::new();
+            backend_err.encode(&mut bytes).unwrap();
+            bytes
+        })
+    }
 }
 
 fn to_nids(ids: Vec<i64>) -> Vec<NoteID> {

rspy/src/lib.rs

@@ -16,7 +16,6 @@ struct Backend {
     backend: RustBackend,
 }
 
-create_exception!(ankirspy, DBError, Exception);
 create_exception!(ankirspy, BackendError, Exception);
 
 #[pyfunction]
@@ -140,12 +139,14 @@ impl Backend {
         .map_err(|err_bytes| BackendError::py_err(err_bytes))
     }
 
+    /// This takes and returns JSON, due to Python's slow protobuf
+    /// encoding/decoding.
     fn db_command(&mut self, py: Python, input: &PyBytes) -> PyResult<PyObject> {
         let in_bytes = input.as_bytes();
         let out_res = py.allow_threads(move || {
             self.backend
-                .db_command(in_bytes)
-                .map_err(|e| DBError::py_err(e.localized_description(&self.backend.i18n())))
+                .run_db_command_bytes(in_bytes)
+                .map_err(|err_bytes| BackendError::py_err(err_bytes))
         });
         let out_bytes = out_res?;
         let out_obj = PyBytes::new(py, &out_bytes);