Enrich fileBrowserPrivate.onFileTransfersUpdated event to support displaying total number of jobs.

chrome/browser/chromeos/extensions/file_manager/event_router.cc

Index: chrome/browser/chromeos/extensions/file_manager/event_router.cc
diff --git a/chrome/browser/chromeos/extensions/file_manager/event_router.cc b/chrome/browser/chromeos/extensions/file_manager/event_router.cc
index 83e1f144e3411613540a81fde51c93277b7299fb..5b831c6a712087df643ed5cd14a1600b7efb2240 100644
--- a/chrome/browser/chromeos/extensions/file_manager/event_router.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/event_router.cc
@@ -10,6 +10,7 @@
 #include "base/prefs/pref_change_registrar.h"
 #include "base/prefs/pref_service.h"
 #include "base/stl_util.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/values.h"
 #include "chrome/browser/app_mode/app_mode_utils.h"
@@ -61,6 +62,7 @@ namespace file_browser_private = extensions::api::file_browser_private;
 namespace file_manager {
 namespace {
 // Constants for the "transferState" field of onFileTransferUpdated event.
+const char kFileTransferStateAdded[] = "added";
 const char kFileTransferStateStarted[] = "started";
 const char kFileTransferStateInProgress[] = "in_progress";
 const char kFileTransferStateCompleted[] = "completed";
@@ -98,6 +100,7 @@ void JobInfoToTransferStatus(
       IsUploadJob(job_info.job_type) ?
       file_browser_private::TRANSFER_TYPE_UPLOAD :
       file_browser_private::TRANSFER_TYPE_DOWNLOAD;
+  status->num_total_jobs = job_info.num_total_jobs;
   // JavaScript does not have 64-bit integers. Instead we use double, which
   // is in IEEE 754 formant and accurate up to 52-bits in JS, and in practice
   // in C++. Larger values are rounded.
@@ -620,7 +623,10 @@ void EventRouter::OnFileManagerPrefsChanged() {
 
 void EventRouter::OnJobAdded(const drive::JobInfo& job_info) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  OnJobUpdated(job_info);
+  if (!drive::IsActiveFileTransferJobInfo(job_info))
+    return;
+  ScheduleDriveFileTransferEvent(
+      job_info, kFileTransferStateAdded, false /* immediate */);
 }
 
 void EventRouter::OnJobUpdated(const drive::JobInfo& job_info) {
@@ -630,14 +636,13 @@ void EventRouter::OnJobUpdated(const drive::JobInfo& job_info) {
 
   bool is_new_job = (drive_jobs_.find(job_info.job_id) == drive_jobs_.end());
 
+  const std::string status =
+      is_new_job ? kFileTransferStateStarted : kFileTransferStateInProgress;
+
   // Replace with the latest job info.
-  drive_jobs_[job_info.job_id] = DriveJobInfoWithStatus(
-      job_info,
-      is_new_job ? kFileTransferStateStarted : kFileTransferStateInProgress);
+  drive_jobs_[job_info.job_id] = DriveJobInfoWithStatus(job_info, status);
 
-  // Fire event if needed.
-  bool always = is_new_job;
-  SendDriveFileTransferEvent(always);
+  ScheduleDriveFileTransferEvent(job_info, status, false /* immediate */);
 }
 
 void EventRouter::OnJobDone(const drive::JobInfo& job_info,
@@ -646,47 +651,71 @@ void EventRouter::OnJobDone(const drive::JobInfo& job_info,
   if (!drive::IsActiveFileTransferJobInfo(job_info))
     return;
 
-  // Replace with the latest job info.
-  drive_jobs_[job_info.job_id] = DriveJobInfoWithStatus(
-      job_info,
-      error == drive::FILE_ERROR_OK ? kFileTransferStateCompleted
-      : kFileTransferStateFailed);
+  const std::string status = error == drive::FILE_ERROR_OK
+                                 ? kFileTransferStateCompleted
+                                 : kFileTransferStateFailed;
 
-  // Fire event if needed.
-  bool always = true;
-  SendDriveFileTransferEvent(always);
+  ScheduleDriveFileTransferEvent(job_info, status, true /* immediate */);
 
   // Forget about the job.
   drive_jobs_.erase(job_info.job_id);
 }
 
-void EventRouter::SendDriveFileTransferEvent(bool always) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+void EventRouter::ScheduleDriveFileTransferEvent(const drive::JobInfo& job_info,
+                                                 const std::string& status,
+                                                 bool immediate) {
+  // Update next send time.
+  base::Time now = base::Time::Now();
+  if (immediate) {
+    next_send_time_ = now;
+  } else if (!drive_job_info_with_status_) {
+    next_send_time_ =

[hirono, 2014/09/01 07:29:01]

Please add comment why we need to delay the events.

[iseki, 2014/09/01 09:26:39]

Done.

+        std::max(now + base::TimeDelta::FromMilliseconds(100), next_send_time_);

[hirono, 2014/09/01 07:29:01]

Please turn the number into constant.
note: We don't have constants of non-primitive types. So we need to define int
constant and pass it to the base::TimeDelta::FromMilliseconds here.

[iseki, 2014/09/01 09:26:39]

Done.

+  }
+
+  // Update the latest event.
+  drive_job_info_with_status_.reset(
+      new DriveJobInfoWithStatus(job_info, status));
+
+  // Schedule event.
+  if (next_send_time_ < now) {
+    SendDriveFileTransferEvent();
+  } else {
+    base::TimeDelta delta = next_send_time_ - now;

[hirono, 2014/09/01 07:29:01]

const

[iseki, 2014/09/01 09:26:39]

Done.

+    base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+        FROM_HERE,
+        base::Bind(&EventRouter::SendDriveFileTransferEvent,
+                   weak_factory_.GetWeakPtr()),
+        delta);
+  }
+}
 
-  // When |always| flag is not set, we don't send the event until certain
-  // amount of time passes after the previous one. This is to avoid
-  // flooding the IPC between extensions by many onFileTransferUpdated events.
-  if (!ShouldSendProgressEvent(always, &last_file_transfer_event_))
+void EventRouter::SendDriveFileTransferEvent() {
+  base::Time now = base::Time::Now();
+  if (now < next_send_time_ || !drive_job_info_with_status_)
     return;
 
-  // Convert the current |drive_jobs_| to IDL type.
+  // Convert the drive_job_info_with_status_ to IDL type.
   std::vector<linked_ptr<file_browser_private::FileTransferStatus> >
       status_list;
-  for (std::map<drive::JobID, DriveJobInfoWithStatus>::iterator
-           iter = drive_jobs_.begin(); iter != drive_jobs_.end(); ++iter) {
-    linked_ptr<file_browser_private::FileTransferStatus> status(
-        new file_browser_private::FileTransferStatus());
-    JobInfoToTransferStatus(profile_,
-                            kFileManagerAppId,
-                            iter->second.status,
-                            iter->second.job_info,
-                            status.get());
-    status_list.push_back(status);
-  }
+
+  linked_ptr<file_browser_private::FileTransferStatus> status(
+      new file_browser_private::FileTransferStatus());
+  JobInfoToTransferStatus(profile_,
+                          kFileManagerAppId,
+                          drive_job_info_with_status_->status,
+                          drive_job_info_with_status_->job_info,
+                          status.get());
+  status_list.push_back(status);
+
+  drive_job_info_with_status_.reset();
+
   BroadcastEvent(
       profile_,
       file_browser_private::OnFileTransfersUpdated::kEventName,
       file_browser_private::OnFileTransfersUpdated::Create(status_list));
+
+  next_send_time_ = now + base::TimeDelta::FromMilliseconds(500);

[hirono, 2014/09/01 07:29:01]

ditto: Please add comment why we need to delay the event. (Maybe readers cannot
find out why the number of milliseconds is different from #673.
ditto: turn it into constant.

[iseki, 2014/09/01 09:26:39]

Done.

[iseki, 2014/09/01 09:26:39]

Done.

 }
 
 void EventRouter::OnDirectoryChanged(const base::FilePath& drive_path) {