contacts: Add contacts::ContactDatabase.

chrome/browser/chromeos/contacts/contact_database.h

+// Copyright (c) 2012 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_CONTACTS_CONTACT_DATABASE_H_
+#define CHROME_BROWSER_CHROMEOS_CONTACTS_CONTACT_DATABASE_H_
+
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/compiler_specific.h"
+#include "base/file_path.h"
+#include "base/memory/ref_counted.h"

[satorux1, 2012/07/31 07:26:30]

is this needed?

[Daniel Erat, 2012/07/31 16:44:12]

Yes, for scoped_refptr. :-)

[satorux1, 2012/07/31 17:34:26]

oh you are right. It's used for the task runner.

I was wary of making classes ref counted (my professor willchan taught me not to
do it in most cases), and checked that ContactDatabase* weren't ref counted. :)

+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+
+namespace base {
+class SequencedTaskRunner;
+}
+
+namespace leveldb {
+class DB;
+}
+
+namespace contacts {
+
+class Contact;
+typedef std::vector<const Contact*> ContactPointers;
+
+// Interface for classes providing persistent storage of Contact objects.
+class ContactDatabaseInterface {
+ public:
+  typedef base::Callback<void(bool success)> InitCallback;
+  typedef base::Callback<void(bool success)> SaveCallback;
+  typedef base::Callback<void(bool success, scoped_ptr<ScopedVector<Contact> >)>
+      LoadCallback;
+
+  ContactDatabaseInterface() {}
+
+  // Asynchronously destroys the object after all in-progress file operations
+  // have completed.
+  virtual void DestroyOnUIThread() {}
+
+  // Asynchronously initializes the object.  |callback| will be invoked on the
+  // UI thread when complete.
+  virtual void Init(const FilePath& database_dir, InitCallback callback) = 0;
+
+  // Asynchronously saves |contacts| to the database.  If |is_full_update| is
+  // true, all existing contacts in the database not present in |contacts| will
+  // be removed.  |callback| will be invoked on the UI thread when complete.
+  // The caller must not make changes to the underlying passed-in Contact
+  // objects until the callback has been invoked.
+  virtual void SaveContacts(scoped_ptr<ContactPointers> contacts,
+                            bool is_full_update,
+                            SaveCallback callback) = 0;
+
+  // Asynchronously loads all contacts from the database and invokes |callback|
+  // when complete.
+  virtual void LoadContacts(LoadCallback callback) = 0;
+
+ protected:
+  virtual ~ContactDatabaseInterface() {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ContactDatabaseInterface);
+};
+
+class ContactDatabase : public ContactDatabaseInterface {
+ public:
+  ContactDatabase();
+
+  // ContactDatabaseInterface implementation.
+  virtual void DestroyOnUIThread() OVERRIDE;
+  virtual void Init(const FilePath& database_dir,
+                    InitCallback callback) OVERRIDE;
+  virtual void SaveContacts(scoped_ptr<ContactPointers> contacts,
+                            bool is_full_update,
+                            SaveCallback callback) OVERRIDE;
+  virtual void LoadContacts(LoadCallback callback) OVERRIDE;
+
+ protected:
+  virtual ~ContactDatabase();
+
+ private:
+  // Are we currently being run by |task_runner_|?
+  bool IsRunByTaskRunner() const;
+
+  // Deletes |this|.
+  void DestroyFromTaskRunner();
+
+  // Initializes the database in |database_dir| and posts |callback| on the UI
+  // thread with the result.
+  void InitFromTaskRunner(const FilePath& database_dir, InitCallback callback);
+
+  // Helper method called by InitFromTaskRunner().  Returns true on success.
+  bool InitInternal(const FilePath& database_dir);
+
+  // Saves |contacts| to disk and invokes |callback| on the UI thread when
+  // complete.
+  void SaveContactsFromTaskRunner(scoped_ptr<ContactPointers> contacts,
+                                  bool is_full_update,
+                                  SaveCallback callback);
+
+  // Loads contacts from disk and passes them to |callback| on the UI thread
+  // when complete.
+  void LoadContactsFromTaskRunner(LoadCallback callback);
+
+  // Helper method called by LoadContactsFromTaskRunner().  Returns true on
+  // success.
+  bool LoadContactsInternal(ScopedVector<Contact>* contacts);
+
+  // Used to run blocking tasks in-order.
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+
+  scoped_ptr<leveldb::DB> db_;
+
+  DISALLOW_COPY_AND_ASSIGN(ContactDatabase);
+};
+
+}  // namespace contacts
+
+#endif  // CHROME_BROWSER_CHROMEOS_CONTACTS_CONTACT_DATABASE_H_