sync: Remove SyncManager::TestingMode in favour of InternalComponentsFactory.

sync/engine/sync_scheduler.h

Index: sync/engine/sync_scheduler.h
diff --git a/sync/engine/sync_scheduler.h b/sync/engine/sync_scheduler.h
index 0ca2f5db5a14be3d236213750e9489eda6a919f6..423516bf77ce50f112abc8fc4dea7557175f2980 100644
--- a/sync/engine/sync_scheduler.h
+++ b/sync/engine/sync_scheduler.h
@@ -10,21 +10,10 @@
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
-#include "base/gtest_prod_util.h"
-#include "base/memory/linked_ptr.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/memory/weak_ptr.h"
-#include "base/observer_list.h"
 #include "base/time.h"
-#include "base/timer.h"
-#include "sync/engine/net/server_connection_manager.h"
 #include "sync/engine/nudge_source.h"
-#include "sync/engine/syncer.h"
 #include "sync/internal_api/public/base/model_type_payload_map.h"
-#include "sync/internal_api/public/engine/polling_constants.h"
-#include "sync/internal_api/public/util/weak_handle.h"
 #include "sync/sessions/sync_session.h"
-#include "sync/sessions/sync_session_context.h"
 
 class MessageLoop;
 
@@ -78,25 +67,20 @@ class SyncScheduler : public sessions::SyncSession::Delegate {
   // All methods of SyncScheduler must be called on the same thread
   // (except for RequestEarlyExit()).
 
-  // |name| is a display string to identify the syncer thread.  Takes
-  // |ownership of |syncer|.
-  SyncScheduler(const std::string& name,
-                sessions::SyncSessionContext* context, Syncer* syncer);
-
-  // Calls Stop().
+  SyncScheduler();
   virtual ~SyncScheduler();
 
   // Start the scheduler with the given mode.  If the scheduler is
   // already started, switch to the given mode, although some
   // scheduled tasks from the old mode may still run.
-  virtual void Start(Mode mode);
+  virtual void Start(Mode mode) = 0;
 
   // Schedules the configuration task specified by |params|. Returns true if
   // the configuration task executed immediately, false if it had to be
   // scheduled for a later attempt. |params.ready_task| is invoked whenever the
   // configuration task executes.
   // Note: must already be in CONFIGURATION mode.
-  virtual bool ScheduleConfiguration(const ConfigurationParams& params);
+  virtual bool ScheduleConfiguration(const ConfigurationParams& params) = 0;
 
   // Request that any running syncer task stop as soon as possible and
   // cancel all scheduled tasks. This function can be called from any thread,
@@ -104,326 +88,30 @@ class SyncScheduler : public sessions::SyncSession::Delegate {
   // allow preempting ongoing sync cycles.
   // Invokes |callback| from the sync loop once syncer is idle and all tasks
   // are cancelled.
-  void RequestStop(const base::Closure& callback);
+  virtual void RequestStop(const base::Closure& callback) = 0;
 
   // The meat and potatoes. Both of these methods will post a delayed task
   // to attempt the actual nudge (see ScheduleNudgeImpl).
-  void ScheduleNudgeAsync(const base::TimeDelta& delay, NudgeSource source,
-                          syncer::ModelTypeSet types,
-                          const tracked_objects::Location& nudge_location);
-  void ScheduleNudgeWithPayloadsAsync(
+  virtual void ScheduleNudgeAsync(
+      const base::TimeDelta& delay,
+      NudgeSource source,
+      syncer::ModelTypeSet types,
+      const tracked_objects::Location& nudge_location) = 0;
+  virtual void ScheduleNudgeWithPayloadsAsync(
       const base::TimeDelta& delay, NudgeSource source,
       const syncer::ModelTypePayloadMap& types_with_payloads,
-      const tracked_objects::Location& nudge_location);
-
-  void CleanupDisabledTypes();
+      const tracked_objects::Location& nudge_location) = 0;
 
   // Change status of notifications in the SyncSessionContext.
-  void set_notifications_enabled(bool notifications_enabled);
+  virtual void SetNotificationsEnabled(bool notifications_enabled) = 0;
 
-  base::TimeDelta sessions_commit_delay() const;
-
-  // DDOS avoidance function.  Calculates how long we should wait before trying
-  // again after a failed sync attempt, where the last delay was |base_delay|.
-  // TODO(tim): Look at URLRequestThrottlerEntryInterface.
-  static base::TimeDelta GetRecommendedDelay(const base::TimeDelta& base_delay);
+  virtual base::TimeDelta GetSessionsCommitDelay() const = 0;
 
   // Called when credentials are updated by the user.
-  void OnCredentialsUpdated();
+  virtual void OnCredentialsUpdated() = 0;
 
   // Called when the network layer detects a connection status change.
-  void OnConnectionStatusChange();
-
-  // SyncSession::Delegate implementation.
-  virtual void OnSilencedUntil(
-      const base::TimeTicks& silenced_until) OVERRIDE;
-  virtual bool IsSyncingCurrentlySilenced() OVERRIDE;
-  virtual void OnReceivedShortPollIntervalUpdate(
-      const base::TimeDelta& new_interval) OVERRIDE;
-  virtual void OnReceivedLongPollIntervalUpdate(
-      const base::TimeDelta& new_interval) OVERRIDE;
-  virtual void OnReceivedSessionsCommitDelay(
-      const base::TimeDelta& new_delay) OVERRIDE;
-  virtual void OnShouldStopSyncingPermanently() OVERRIDE;
-  virtual void OnSyncProtocolError(
-      const sessions::SyncSessionSnapshot& snapshot) OVERRIDE;
-
- private:
-  enum JobProcessDecision {
-    // Indicates we should continue with the current job.
-    CONTINUE,
-    // Indicates that we should save it to be processed later.
-    SAVE,
-    // Indicates we should drop this job.
-    DROP,
-  };
-
-  struct SyncSessionJob {
-    // An enum used to describe jobs for scheduling purposes.
-    enum SyncSessionJobPurpose {
-      // Uninitialized state, should never be hit in practice.
-      UNKNOWN = -1,
-      // Our poll timer schedules POLL jobs periodically based on a server
-      // assigned poll interval.
-      POLL,
-      // A nudge task can come from a variety of components needing to force
-      // a sync.  The source is inferable from |session.source()|.
-      NUDGE,
-      // Typically used for fetching updates for a subset of the enabled types
-      // during initial sync or reconfiguration.  We don't run all steps of
-      // the sync cycle for these (e.g. CleanupDisabledTypes is skipped).
-      CONFIGURATION,
-      // The user disabled some types and we have to clean up the data
-      // for those.
-      CLEANUP_DISABLED_TYPES,
-    };
-    SyncSessionJob();
-    SyncSessionJob(SyncSessionJobPurpose purpose, base::TimeTicks start,
-        linked_ptr<sessions::SyncSession> session, bool is_canary_job,
-        const ConfigurationParams& config_params,
-        const tracked_objects::Location& nudge_location);
-    ~SyncSessionJob();
-    static const char* GetPurposeString(SyncSessionJobPurpose purpose);
-
-    SyncSessionJobPurpose purpose;
-    base::TimeTicks scheduled_start;
-    linked_ptr<sessions::SyncSession> session;
-    bool is_canary_job;
-    ConfigurationParams config_params;
-
-    // This is the location the job came from.  Used for debugging.
-    // In case of multiple nudges getting coalesced this stores the
-    // first location that came in.
-    tracked_objects::Location from_here;
-  };
-  friend class SyncSchedulerTest;
-  friend class SyncSchedulerWhiteboxTest;
-  friend class SyncerTest;
-
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest,
-      DropNudgeWhileExponentialBackOff);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest, SaveNudge);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest,
-                           SaveNudgeWhileTypeThrottled);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest, ContinueNudge);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest, DropPoll);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest, ContinuePoll);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest, ContinueConfiguration);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest,
-                           SaveConfigurationWhileThrottled);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest,
-                           SaveNudgeWhileThrottled);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest,
-                           ContinueCanaryJobConfig);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerWhiteboxTest,
-      ContinueNudgeWhileExponentialBackOff);
-  FRIEND_TEST_ALL_PREFIXES(SyncSchedulerTest, TransientPollFailure);
-
-  // A component used to get time delays associated with exponential backoff.
-  // Encapsulated into a class to facilitate testing.
-  class DelayProvider {
-   public:
-    DelayProvider();
-    virtual base::TimeDelta GetDelay(const base::TimeDelta& last_delay);
-    virtual ~DelayProvider();
-   private:
-    DISALLOW_COPY_AND_ASSIGN(DelayProvider);
-  };
-
-  struct WaitInterval {
-    enum Mode {
-      // Uninitialized state, should not be set in practice.
-      UNKNOWN = -1,
-      // A wait interval whose duration has been affected by exponential
-      // backoff.
-      // EXPONENTIAL_BACKOFF intervals are nudge-rate limited to 1 per interval.
-      EXPONENTIAL_BACKOFF,
-      // A server-initiated throttled interval.  We do not allow any syncing
-      // during such an interval.
-      THROTTLED,
-    };
-    WaitInterval();
-    ~WaitInterval();
-    WaitInterval(Mode mode, base::TimeDelta length);
-
-    static const char* GetModeString(Mode mode);
-
-    Mode mode;
-
-    // This bool is set to true if we have observed a nudge during this
-    // interval and mode == EXPONENTIAL_BACKOFF.
-    bool had_nudge;
-    base::TimeDelta length;
-    base::OneShotTimer<SyncScheduler> timer;
-
-    // Configure jobs are saved only when backing off or throttling. So we
-    // expose the pointer here.
-    scoped_ptr<SyncSessionJob> pending_configure_job;
-  };
-
-  static const char* GetModeString(Mode mode);
-
-  static const char* GetDecisionString(JobProcessDecision decision);
-
-  // Assign |start| and |end| to appropriate SyncerStep values for the
-  // specified |purpose|.
-  static void SetSyncerStepsForPurpose(
-      SyncSessionJob::SyncSessionJobPurpose purpose,
-      SyncerStep* start, SyncerStep* end);
-
-  // Helpers that log before posting to |sync_loop_|.  These will only post
-  // the task in between calls to Start/Stop.
-  void PostTask(const tracked_objects::Location& from_here,
-                const char* name,
-                const base::Closure& task);
-  void PostDelayedTask(const tracked_objects::Location& from_here,
-                       const char* name,
-                       const base::Closure& task,
-                       base::TimeDelta delay);
-
-  // Helper to assemble a job and post a delayed task to sync.
-  void ScheduleSyncSessionJob(const SyncSessionJob& job);
-
-  // Invoke the Syncer to perform a sync.
-  void DoSyncSessionJob(const SyncSessionJob& job);
-
-  // Called after the Syncer has performed the sync represented by |job|, to
-  // reset our state.
-  void FinishSyncSessionJob(const SyncSessionJob& job);
-
-  // Record important state that might be needed in future syncs, such as which
-  // data types may require cleanup.
-  void UpdateCarryoverSessionState(const SyncSessionJob& old_job);
-
-  // Helper to FinishSyncSessionJob to schedule the next sync operation.
-  void ScheduleNextSync(const SyncSessionJob& old_job);
-
-  // Helper to configure polling intervals. Used by Start and ScheduleNextSync.
-  void AdjustPolling(const SyncSessionJob* old_job);
-
-  // Helper to restart waiting with |wait_interval_|'s timer.
-  void RestartWaiting();
-
-  // Helper to ScheduleNextSync in case of consecutive sync errors.
-  void HandleContinuationError(const SyncSessionJob& old_job);
-
-  // Determines if it is legal to run |job| by checking current
-  // operational mode, backoff or throttling, freshness
-  // (so we don't make redundant syncs), and connection.
-  bool ShouldRunJob(const SyncSessionJob& job);
-
-  // Decide whether we should CONTINUE, SAVE or DROP the job.
-  JobProcessDecision DecideOnJob(const SyncSessionJob& job);
-
-  // Decide on whether to CONTINUE, SAVE or DROP the job when we are in
-  // backoff mode.
-  JobProcessDecision DecideWhileInWaitInterval(const SyncSessionJob& job);
-
-  // Saves the job for future execution. Note: It drops all the poll jobs.
-  void SaveJob(const SyncSessionJob& job);
-
-  // Coalesces the current job with the pending nudge.
-  void InitOrCoalescePendingJob(const SyncSessionJob& job);
-
-  // 'Impl' here refers to real implementation of public functions, running on
-  // |thread_|.
-  void StopImpl(const base::Closure& callback);
-  void ScheduleNudgeImpl(
-      const base::TimeDelta& delay,
-      sync_pb::GetUpdatesCallerInfo::GetUpdatesSource source,
-      const syncer::ModelTypePayloadMap& types_with_payloads,
-      bool is_canary_job, const tracked_objects::Location& nudge_location);
-
-  // Returns true if the client is currently in exponential backoff.
-  bool IsBackingOff() const;
-
-  // Helper to signal all listeners registered with |session_context_|.
-  void Notify(SyncEngineEvent::EventCause cause);
-
-  // Callback to change backoff state.
-  void DoCanaryJob();
-  void Unthrottle();
-
-  // Executes the pending job. Called whenever an event occurs that may
-  // change conditions permitting a job to run. Like when network connection is
-  // re-established, mode changes etc.
-  void DoPendingJobIfPossible(bool is_canary_job);
-
-  // Called when the root cause of the current connection error is fixed.
-  void OnServerConnectionErrorFixed();
-
-  // The pointer is owned by the caller.
-  syncer::sessions::SyncSession* CreateSyncSession(
-      const syncer::sessions::SyncSourceInfo& info);
-
-  // Creates a session for a poll and performs the sync.
-  void PollTimerCallback();
-
-  // Used to update |connection_code_|, see below.
-  void UpdateServerConnectionManagerStatus(
-      HttpResponse::ServerConnectionCode code);
-
-  // Called once the first time thread_ is started to broadcast an initial
-  // session snapshot containing data like initial_sync_ended.  Important when
-  // the client starts up and does not need to perform an initial sync.
-  void SendInitialSnapshot();
-
-  virtual void OnActionableError(const sessions::SyncSessionSnapshot& snapshot);
-
-  base::WeakPtrFactory<SyncScheduler> weak_ptr_factory_;
-
-  // A second factory specially for weak_handle_this_, to allow the handle
-  // to be const and alleviate threading concerns.
-  base::WeakPtrFactory<SyncScheduler> weak_ptr_factory_for_weak_handle_;
-
-  // For certain methods that need to worry about X-thread posting.
-  const WeakHandle<SyncScheduler> weak_handle_this_;
-
-  // Used for logging.
-  const std::string name_;
-
-  // The message loop this object is on.  Almost all methods have to
-  // be called on this thread.
-  MessageLoop* const sync_loop_;
-
-  // Set in Start(), unset in Stop().
-  bool started_;
-
-  // Modifiable versions of kDefaultLongPollIntervalSeconds which can be
-  // updated by the server.
-  base::TimeDelta syncer_short_poll_interval_seconds_;
-  base::TimeDelta syncer_long_poll_interval_seconds_;
-
-  // Server-tweakable sessions commit delay.
-  base::TimeDelta sessions_commit_delay_;
-
-  // Periodic timer for polling.  See AdjustPolling.
-  base::RepeatingTimer<SyncScheduler> poll_timer_;
-
-  // The mode of operation.
-  Mode mode_;
-
-  // TODO(tim): Bug 26339. This needs to track more than just time I think,
-  // since the nudges could be for different types. Current impl doesn't care.
-  base::TimeTicks last_sync_session_end_time_;
-
-  // The latest connection code we got while trying to connect.
-  HttpResponse::ServerConnectionCode connection_code_;
-
-  // Tracks in-flight nudges so we can coalesce.
-  scoped_ptr<SyncSessionJob> pending_nudge_;
-
-  // Current wait state.  Null if we're not in backoff and not throttled.
-  scoped_ptr<WaitInterval> wait_interval_;
-
-  scoped_ptr<DelayProvider> delay_provider_;
-
-  // Invoked to run through the sync cycle.
-  scoped_ptr<Syncer> syncer_;
-
-  sessions::SyncSessionContext *session_context_;
-
-  DISALLOW_COPY_AND_ASSIGN(SyncScheduler);
+  virtual void OnConnectionStatusChange() = 0;
 };
 
 }  // namespace syncer