Add an observer interface for DriveScheduler.

chrome/browser/chromeos/drive/drive_job_list_interface.h

Index: chrome/browser/chromeos/drive/drive_job_list_interface.h
diff --git a/chrome/browser/chromeos/drive/drive_job_list_interface.h b/chrome/browser/chromeos/drive/drive_job_list_interface.h
new file mode 100644
index 0000000000000000000000000000000000000000..5f0e7a874677a7092a8da4be0fd62070d67d895a
--- /dev/null
+++ b/chrome/browser/chromeos/drive/drive_job_list_interface.h
@@ -0,0 +1,109 @@
+// Copyright 2013 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_DRIVE_DRIVE_JOB_LIST_INTERFACE_H_
+#define CHROME_BROWSER_CHROMEOS_DRIVE_DRIVE_JOB_LIST_INTERFACE_H_
+
+#include "base/basictypes.h"
+#include "base/files/file_path.h"
+
+namespace drive {
+
+// Enum representing the type of job.
+enum JobType {
+  TYPE_GET_ABOUT_RESOURCE,
+  TYPE_GET_ACCOUNT_METADATA,
+  TYPE_GET_APP_LIST,
+  TYPE_GET_ALL_RESOURCE_LIST,
+  TYPE_GET_RESOURCE_LIST_IN_DIRECTORY,
+  TYPE_SEARCH,
+  TYPE_GET_CHANGE_LIST,
+  TYPE_CONTINUE_GET_RESOURCE_LIST,
+  TYPE_GET_RESOURCE_ENTRY,
+  TYPE_DELETE_RESOURCE,
+  TYPE_COPY_HOSTED_DOCUMENT,
+  TYPE_RENAME_RESOURCE,
+  TYPE_ADD_RESOURCE_TO_DIRECTORY,
+  TYPE_REMOVE_RESOURCE_FROM_DIRECTORY,
+  TYPE_ADD_NEW_DIRECTORY,
+  TYPE_DOWNLOAD_FILE,
+  TYPE_UPLOAD_NEW_FILE,
+  TYPE_UPLOAD_EXISTING_FILE,
+};
+
+// Current state of the job.
+enum JobState {
+  // The job is queued, but not yet executed.
+  STATE_NONE,
+
+  // The job is in the process of being handled.
+  STATE_RUNNING,
+
+  // The job failed, but has been re-added to the queue.
+  STATE_RETRY,
+};
+
+// Unique ID assigned to each job.
+typedef int32 JobID;
+
+// Information about a specific job that is visible to other systems.
+struct JobInfo {
+  explicit JobInfo(JobType in_job_type)
+      : job_type(in_job_type),
+        job_id(-1),
+        completed_bytes(0),
+        total_bytes(0),
+        state(STATE_NONE) {
+  }
+
+  // Type of the job.
+  JobType job_type;
+
+  // Id of the job, which can be used to query or modify it.
+  JobID job_id;
+
+  // Number of bytes completed, if applicable.
+  int completed_bytes;

[satorux1, 2013/04/17 00:11:29]

maybe num_completed_bytes

[kinaba, 2013/04/17 00:51:42]

Done. Along the way changed the type to int64.

+
+  // Total bytes of this operation, if applicable.
+  int total_bytes;

[satorux1, 2013/04/17 00:11:29]

add num_ ?

[kinaba, 2013/04/17 00:51:42]

Done.

+
+  // Drive path of the file that this job acts on.
+  base::FilePath file_path;
+
+  // Current state of the operation.
+  JobState state;
+};
+
+// The interface for observing DriveJobListInterface.
+class DriveJobListObserver {

[tfarina, 2013/04/16 14:07:28]

does this needs a protected virtual destructor?

[satorux1, 2013/04/17 00:11:29]

Let's drop 'Drive' prefix

[kinaba, 2013/04/17 00:51:42]

Done.

[kinaba, 2013/04/17 00:51:42]

Done. Thanks.

+ public:
+  // Called when a new job id added.
+  virtual void OnJobAdded(const JobInfo& job_info) = 0;
+
+  // Called when a job id finished.
+  virtual void OnJobDone(const JobInfo& job_info) = 0;
+
+  // Called when a job status is updated.
+  virtual void OnJobUpdated(const JobInfo& job_info) = 0;

[satorux1, 2013/04/17 00:11:29]

Not sure if all of these should be pure virtual. Are observers always interested
in all of the events? 

[kinaba, 2013/04/17 00:51:42]

Not sure but there may be a case that some of them are not needed.
Changed to empty body.

+};
+
+// The interface to expose the list of issued Drive jobs.
+class DriveJobListInterface {

[satorux1, 2013/04/17 00:11:29]

Ditto. Drop 'Drive'. Please change the file names too.

[kinaba, 2013/04/17 00:51:42]

Done.

+ public:
+  virtual ~DriveJobListInterface() {}
+
+  // Returns the list of jobs currently managed by the scheduler.
+  virtual std::vector<JobInfo> GetJobInfoList() = 0;
+
+  // Adds an observer.
+  virtual void AddObserver(DriveJobListObserver* observer) = 0;
+
+  // Removes an observer.
+  virtual void RemoveObserver(DriveJobListObserver* observer) = 0;
+};
+
+}  // namespace drive
+
+#endif  // CHROME_BROWSER_CHROMEOS_DRIVE_DRIVE_JOB_LIST_INTERFACE_H_