Update AttachmentServiceImpl to retry attachment uploads.

sync/internal_api/attachments/task_queue_unittest.cc

+// Copyright 2014 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 "sync/internal_api/public/attachments/task_queue.h"
+
+#include <vector>
+
+#include "base/bind.h"
+#include "base/memory/weak_ptr.h"
+#include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
+#include "base/timer/mock_timer.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using base::TimeDelta;
+
+namespace syncer {
+
+namespace {
+
+const TimeDelta kZero;
+
+}  // namespace
+
+class TaskQueueTest : public testing::Test {
+ protected:
+  TaskQueueTest() : weak_ptr_factory_(this) {
+    queue_.reset(new TaskQueue<int>(
+        base::Bind(&TaskQueueTest::Process, weak_ptr_factory_.GetWeakPtr()),
+        TimeDelta::FromMinutes(1),
+        TimeDelta::FromMinutes(8)));
+  }
+
+  void RunLoop() {
+    base::RunLoop run_loop;
+    run_loop.RunUntilIdle();
+  }
+
+  void Process(const int& task) { dispatched_.push_back(task); }
+
+  base::MessageLoop message_loop_;
+  scoped_ptr<TaskQueue<int> > queue_;
+  std::vector<int> dispatched_;
+  base::WeakPtrFactory<TaskQueueTest> weak_ptr_factory_;
+};
+
+// See that at most one task is dispatched at a time.
+TEST_F(TaskQueueTest, AddToQueue_NoConcurrentTasks) {
+  queue_->AddToQueue(1);
+  queue_->AddToQueue(2);
+  RunLoop();
+
+  // Only one has been dispatched.
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(1, dispatched_.front());
+  RunLoop();
+
+  // Still only one.
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(1, dispatched_.front());
+  dispatched_.clear();
+  queue_->MarkAsSucceeded(1);
+  RunLoop();
+
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(2, dispatched_.front());
+  dispatched_.clear();
+  queue_->MarkAsSucceeded(2);
+  RunLoop();
+
+  ASSERT_TRUE(dispatched_.empty());
+}
+
+// See that that the queue ignores duplicate adds.
+TEST_F(TaskQueueTest, AddToQueue_NoDuplicates) {
+  queue_->AddToQueue(1);
+  queue_->AddToQueue(1);
+  queue_->AddToQueue(2);
+  queue_->AddToQueue(1);
+  ASSERT_TRUE(dispatched_.empty());
+  RunLoop();
+
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(1, dispatched_.front());
+  dispatched_.clear();
+  queue_->MarkAsSucceeded(1);
+  RunLoop();
+
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(2, dispatched_.front());
+  dispatched_.clear();
+  queue_->MarkAsSucceeded(2);
+  RunLoop();
+
+  ASSERT_TRUE(dispatched_.empty());
+}
+
+// See that Retry works as expected.
+TEST_F(TaskQueueTest, Retry) {
+  scoped_ptr<base::MockTimer> timer_to_pass(new base::MockTimer(false, false));
+  base::MockTimer* mock_timer = timer_to_pass.get();
+  queue_->SetTimerForTest(timer_to_pass.PassAs<base::Timer>());
+
+  // 1st attempt.
+  queue_->AddToQueue(1);
+  ASSERT_TRUE(mock_timer->IsRunning());
+  ASSERT_EQ(TimeDelta(), mock_timer->GetCurrentDelay());
+  TimeDelta last_delay = mock_timer->GetCurrentDelay();
+  mock_timer->Fire();
+  RunLoop();
+
+  // 2nd attempt.
+  ASSERT_FALSE(mock_timer->IsRunning());
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(1, dispatched_.front());
+  dispatched_.clear();
+  queue_->Retry(1);
+  ASSERT_TRUE(mock_timer->IsRunning());
+  EXPECT_GT(mock_timer->GetCurrentDelay(), last_delay);
+  EXPECT_LE(mock_timer->GetCurrentDelay(), TimeDelta::FromMinutes(1));
+  last_delay = mock_timer->GetCurrentDelay();
+  mock_timer->Fire();
+  RunLoop();
+
+  // 3rd attempt.
+  ASSERT_FALSE(mock_timer->IsRunning());
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(1, dispatched_.front());
+  dispatched_.clear();
+  queue_->Retry(1);
+  ASSERT_TRUE(mock_timer->IsRunning());
+  EXPECT_GT(mock_timer->GetCurrentDelay(), last_delay);
+  last_delay = mock_timer->GetCurrentDelay();
+  mock_timer->Fire();
+  RunLoop();
+
+  // Give up.
+  ASSERT_FALSE(mock_timer->IsRunning());
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(1, dispatched_.front());
+  dispatched_.clear();
+  queue_->Cancel(1);
+  ASSERT_FALSE(mock_timer->IsRunning());
+
+  // Try a different task.  See the timer remains unchanged because the previous
+  // task was marked as failed.
+  ASSERT_TRUE(dispatched_.empty());
+  queue_->AddToQueue(2);
+  ASSERT_TRUE(mock_timer->IsRunning());
+  EXPECT_GE(last_delay, mock_timer->GetCurrentDelay());
+  last_delay = mock_timer->GetCurrentDelay();
+  mock_timer->Fire();
+  RunLoop();
+
+  // Mark this one as succeeding, which will clear the backoff delay.
+  ASSERT_FALSE(mock_timer->IsRunning());
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(2, dispatched_.front());
+  dispatched_.clear();
+  queue_->MarkAsSucceeded(2);
+  ASSERT_FALSE(mock_timer->IsRunning());
+
+  // Add one last task and see that it's dispatched without delay because the
+  // previous one succeeded.
+  ASSERT_TRUE(dispatched_.empty());
+  queue_->AddToQueue(3);
+  ASSERT_TRUE(mock_timer->IsRunning());
+  EXPECT_LT(mock_timer->GetCurrentDelay(), last_delay);
+  last_delay = mock_timer->GetCurrentDelay();
+  mock_timer->Fire();
+  RunLoop();
+
+  // Clean up.
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(3, dispatched_.front());
+  dispatched_.clear();
+  queue_->MarkAsSucceeded(3);
+  ASSERT_FALSE(mock_timer->IsRunning());
+}
+
+// See that a task marked as canceled is not retried.
+TEST_F(TaskQueueTest, Cancel_NoRetry) {
+  queue_->AddToQueue(1);
+  RunLoop();
+
+  ASSERT_EQ(1U, dispatched_.size());
+  EXPECT_EQ(1, dispatched_.front());
+  dispatched_.clear();
+  queue_->Cancel(1);
+  RunLoop();
+
+  ASSERT_TRUE(dispatched_.empty());
+}
+
+}  // namespace syncer