Implement a DRIVE_REQUEST_TOO_LARGE backoff.

google_apis/drive/files_list_request_runner.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "google_apis/drive/files_list_request_runner.h"
+
+#include "base/bind.h"
+#include "google_apis/drive/drive_api_error_codes.h"
+#include "google_apis/drive/drive_api_requests.h"
+#include "google_apis/drive/request_sender.h"
+
+namespace google_apis {
+
+FilesListRequestRunner::FilesListRequestRunner(
+    RequestSender* request_sender,
+    const google_apis::DriveApiUrlGenerator& url_generator)
+    : request_sender_(request_sender),
+      url_generator_(url_generator),
+      weak_ptr_factory_(this) {
+}
+
+FilesListRequestRunner::~FilesListRequestRunner() {
+}
+
+CancelCallback FilesListRequestRunner::CreateAndStartWithSizeBackoff(
+    int max_results,
+    const std::string& q,
+    const std::string& fields,
+    const FileListCallback& callback) {
+  base::Closure* const cancel_callback = new base::Closure;
+  drive::FilesListRequest* const request = new drive::FilesListRequest(
+      request_sender_, url_generator_,
+      base::Bind(&FilesListRequestRunner::OnCompleted,
+                 weak_ptr_factory_.GetWeakPtr(), max_results, q, fields,
+                 callback, base::Owned(cancel_callback)));
+  request->set_max_results(max_results);
+  request->set_q(q);
+  request->set_fields(fields);
+  *cancel_callback = request_sender_->StartRequestWithAuthRetry(request);
+
+  // The cancellation callback is owned by the completion callback, so it must
+  // not be used after |callback| is called.
+  return base::Bind(&FilesListRequestRunner::OnCancel,
+                    weak_ptr_factory_.GetWeakPtr(),
+                    base::Unretained(cancel_callback));
+}
+
+void FilesListRequestRunner::OnCancel(base::Closure* cancel_callback) {
+  DCHECK(cancel_callback);
+  DCHECK(!cancel_callback->is_null());
+  cancel_callback->Run();
+}
+
+void FilesListRequestRunner::OnCompleted(int max_results,
+                                         const std::string& q,
+                                         const std::string& fields,
+                                         const FileListCallback& callback,
+                                         CancelCallback* cancel_callback,
+                                         DriveApiErrorCode error,
+                                         scoped_ptr<FileList> entry) {
+  if (!request_completed_callback_for_testing_.is_null())
+    request_completed_callback_for_testing_.Run();
+
+  if (error == google_apis::DRIVE_RESPONSE_TOO_LARGE && max_results > 1) {
+    CreateAndStartWithSizeBackoff(max_results / 2, q, fields, callback);
+    return;
+  }
+
+  callback.Run(error, entry.Pass());
+}
+
+void FilesListRequestRunner::SetRequestCompletedCallbackForTesting(
+    const base::Closure& callback) {
+  request_completed_callback_for_testing_ = callback;
+}
+
+}  // namespace google_apis