Fix bugs in wrapper around gcloud rewrite

Two things were working incorrectly:
- The objects were not using percent encoding, resulting in an
incorrect uri, and
- the response was incorrectly parsed due to an incorrect decoder

src/storage.ml

@@ -94,7 +94,7 @@ type rewrite_object_response = {
   kind : string;
   total_bytes_rewritten : string; [@key "totalBytesRewritten"]
   object_size : string; [@key "objectSize"]
-  done_ : bool;
+  done_ : bool; [@key "done"]
   rewrite_token : string option; [@key "rewriteToken"] [@default None]
   resource : Yojson.Safe.t option; [@default None]
 }
@@ -111,11 +111,15 @@ let rewrite_object source_bucket source_object destination_bucket
   Lwt.catch
     (fun () ->
       let uri =
+        let source_object = Uri.pct_encode source_object in
+        let destination_object = Uri.pct_encode destination_object in
         Uri.make () ~scheme:"https" ~host:"storage.googleapis.com"
           ~path:
             (Printf.sprintf "storage/v1/b/%s/o/%s/rewriteTo/b/%s/o/%s"
                source_bucket source_object destination_bucket destination_object)
       in
+      print_endline "important check hehre";
+      print_endline (Uri.to_string uri);
       let headers =
         Cohttp.Header.of_list
           [
@@ -130,8 +134,11 @@ let rewrite_object source_bucket source_object destination_bucket
   >>= fun (resp, body) ->
   match Cohttp.Response.status resp with
   | `OK ->
+      print_endline "we ok'd here";
       Error.parse_body_json rewrite_object_response_of_yojson body |> Lwt.return
-  | status_code -> Error.of_response_status_code_and_body status_code body
+  | status_code ->
+      print_endline "we error'd here";
+      Error.of_response_status_code_and_body status_code body
 
 [@@@warning "-39"]