[Sync] Move //components/sync_driver to //components/sync/driver.

components/sync_driver/sync_service.h

-// Copyright 2015 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 COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_H_
-#define COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_H_
-
-#include <memory>
-#include <string>
-
-#include "base/callback.h"
-#include "base/location.h"
-#include "base/macros.h"
-#include "base/memory/weak_ptr.h"
-#include "base/time/time.h"
-#include "components/sync/base/model_type.h"
-#include "components/sync/core/connection_status.h"
-#include "components/sync_driver/data_type_encryption_handler.h"
-#include "components/sync_driver/sync_service_observer.h"
-#include "google_apis/gaia/google_service_auth_error.h"
-
-class GoogleServiceAuthError;
-
-namespace browser_sync {
-class ProtocolEventObserver;
-}
-
-namespace syncer {
-
-class BaseTransaction;
-class JsController;
-class TypeDebugInfoObserver;
-struct SyncStatus;
-struct UserShare;
-
-namespace sessions {
-class SyncSessionSnapshot;
-}  // namespace sessions
-
-}  // namespace syncer
-
-namespace sync_driver {
-
-class DataTypeController;
-class LocalDeviceInfoProvider;
-class OpenTabsUIDelegate;
-class SyncClient;
-
-// UIs that need to prevent Sync startup should hold an instance of this class
-// until the user has finished modifying sync settings. This is not an inner
-// class of SyncService to enable forward declarations.
-class SyncSetupInProgressHandle {
- public:
-  // UIs should not construct this directly, but instead call
-  // SyncService::GetSetupInProgress().
-  explicit SyncSetupInProgressHandle(base::Closure on_destroy);
-
-  ~SyncSetupInProgressHandle();
-
- private:
-  base::Closure on_destroy_;
-};
-
-class SyncService : public DataTypeEncryptionHandler {
- public:
-  // Used to specify the kind of passphrase with which sync data is encrypted.
-  enum PassphraseType {
-    IMPLICIT,  // The user did not provide a custom passphrase for encryption.
-               // We implicitly use the GAIA password in such cases.
-    EXPLICIT,  // The user selected the "use custom passphrase" radio button
-               // during sync setup and provided a passphrase.
-  };
-
-  // Passed as an argument to RequestStop to control whether or not the sync
-  // backend should clear its data directory when it shuts down. See
-  // RequestStop for more information.
-  enum SyncStopDataFate {
-    KEEP_DATA,
-    CLEAR_DATA,
-  };
-
-  // Status of sync server connection, sync token and token request.
-  struct SyncTokenStatus {
-    SyncTokenStatus();
-
-    // Sync server connection status reported by sync backend.
-    base::Time connection_status_update_time;
-    syncer::ConnectionStatus connection_status;
-
-    // Times when OAuth2 access token is requested and received.
-    base::Time token_request_time;
-    base::Time token_receive_time;
-
-    // Error returned by OAuth2TokenService for token request and time when
-    // next request is scheduled.
-    GoogleServiceAuthError last_get_token_error;
-    base::Time next_token_request_time;
-  };
-
-  ~SyncService() override {}
-
-  // Whether sync is enabled by user or not. This does not necessarily mean
-  // that sync is currently running (due to delayed startup, unrecoverable
-  // errors, or shutdown). See IsSyncActive below for checking whether sync
-  // is actually running.
-  virtual bool IsFirstSetupComplete() const = 0;
-
-  // Whether sync is allowed to start. Command line flags, platform-level
-  // overrides, and account-level overrides are examples of reasons this
-  // might be false.
-  virtual bool IsSyncAllowed() const = 0;
-
-  // Returns true if sync is fully initialized and active. This implies that
-  // an initial configuration has successfully completed, although there may
-  // be datatype specific, auth, or other transient errors. To see which
-  // datetypes are actually syncing, see GetActiveTypes() below.
-  virtual bool IsSyncActive() const = 0;
-
-  // Triggers a GetUpdates call for the specified |types|, pulling any new data
-  // from the sync server.
-  virtual void TriggerRefresh(const syncer::ModelTypeSet& types) = 0;
-
-  // Get the set of current active data types (those chosen or configured by
-  // the user which have not also encountered a runtime error).
-  // Note that if the Sync engine is in the middle of a configuration, this
-  // will the the empty set. Once the configuration completes the set will
-  // be updated.
-  virtual syncer::ModelTypeSet GetActiveDataTypes() const = 0;
-
-  // Returns the SyncClient instance associated with this service.
-  virtual SyncClient* GetSyncClient() const = 0;
-
-  // Adds/removes an observer. SyncService does not take ownership of the
-  // observer.
-  virtual void AddObserver(SyncServiceObserver* observer) = 0;
-  virtual void RemoveObserver(SyncServiceObserver* observer) = 0;
-
-  // Returns true if |observer| has already been added as an observer.
-  virtual bool HasObserver(const SyncServiceObserver* observer) const = 0;
-
-  // ---------------------------------------------------------------------------
-  // TODO(sync): The methods below were pulled from ProfileSyncService, and
-  // should be evaluated to see if they should stay.
-
-  // Called when a datatype (SyncableService) has a need for sync to start
-  // ASAP, presumably because a local change event has occurred but we're
-  // still in deferred start mode, meaning the SyncableService hasn't been
-  // told to MergeDataAndStartSyncing yet.
-  virtual void OnDataTypeRequestsSyncStartup(syncer::ModelType type) = 0;
-
-  // Returns true if sync is allowed, requested, and the user is logged in.
-  // (being logged in does not mean that tokens are available - tokens may
-  // be missing because they have not loaded yet, or because they were deleted
-  // due to http://crbug.com/121755).
-  virtual bool CanSyncStart() const = 0;
-
-  // Stops sync at the user's request. |data_fate| controls whether the sync
-  // backend should clear its data directory when it shuts down. Generally
-  // KEEP_DATA is used when the user just stops sync, and CLEAR_DATA is used
-  // when they sign out of the profile entirely.
-  virtual void RequestStop(SyncStopDataFate data_fate) = 0;
-
-  // The user requests that sync start. This only actually starts sync if
-  // IsSyncAllowed is true and the user is signed in. Once sync starts,
-  // other things such as IsFirstSetupComplete being false can still prevent
-  // it from moving into the "active" state.
-  virtual void RequestStart() = 0;
-
-  // Returns the set of types which are preferred for enabling. This is a
-  // superset of the active types (see GetActiveDataTypes()).
-  virtual syncer::ModelTypeSet GetPreferredDataTypes() const = 0;
-
-  // Called when a user chooses which data types to sync. |sync_everything|
-  // represents whether they chose the "keep everything synced" option; if
-  // true, |chosen_types| will be ignored and all data types will be synced.
-  // |sync_everything| means "sync all current and future data types."
-  // |chosen_types| must be a subset of syncer::UserSelectableTypes().
-  virtual void OnUserChoseDatatypes(bool sync_everything,
-                                    syncer::ModelTypeSet chosen_types) = 0;
-
-  // Called whe Sync has been setup by the user and can be started.
-  virtual void SetFirstSetupComplete() = 0;
-
-  // Returns true if initial sync setup is in progress (does not return true
-  // if the user is customizing sync after already completing setup once).
-  // SyncService uses this to determine if it's OK to start syncing, or if the
-  // user is still setting up the initial sync configuration.
-  virtual bool IsFirstSetupInProgress() const = 0;
-
-  // Called by the UI to notify the SyncService that UI is visible so it will
-  // not start syncing. This tells sync whether it's safe to start downloading
-  // data types yet (we don't start syncing until after sync setup is complete).
-  // The UI calls this and holds onto the instance for as long as any part of
-  // the signin wizard is displayed (even just the login UI).
-  // When the last outstanding handle is deleted, this kicks off the sync engine
-  // to ensure that data download starts. In this case,
-  // |ReconfigureDatatypeManager| will get triggered.
-  virtual std::unique_ptr<SyncSetupInProgressHandle>
-  GetSetupInProgressHandle() = 0;
-
-  // Used by tests.
-  virtual bool IsSetupInProgress() const = 0;
-
-  // Whether the data types active for the current mode have finished
-  // configuration.
-  virtual bool ConfigurationDone() const = 0;
-
-  virtual const GoogleServiceAuthError& GetAuthError() const = 0;
-  virtual bool HasUnrecoverableError() const = 0;
-
-  // Returns true if the SyncBackendHost has told us it's ready to accept
-  // changes. This should only be used for sync's internal configuration logic
-  // (such as deciding when to prompt for an encryption passphrase).
-  virtual bool IsBackendInitialized() const = 0;
-
-  // Return the active OpenTabsUIDelegate. If sessions is not enabled or not
-  // currently syncing, returns nullptr.
-  virtual OpenTabsUIDelegate* GetOpenTabsUIDelegate() = 0;
-
-  // Returns true if OnPassphraseRequired has been called for decryption and
-  // we have an encrypted data type enabled.
-  virtual bool IsPassphraseRequiredForDecryption() const = 0;
-
-  // Returns the time the current explicit passphrase (if any), was set.
-  // If no secondary passphrase is in use, or no time is available, returns an
-  // unset base::Time.
-  virtual base::Time GetExplicitPassphraseTime() const = 0;
-
-  // Returns true if a secondary (explicit) passphrase is being used. It is not
-  // legal to call this method before the backend is initialized.
-  virtual bool IsUsingSecondaryPassphrase() const = 0;
-
-  // Turns on encryption for all data. Callers must call OnUserChoseDatatypes()
-  // after calling this to force the encryption to occur.
-  virtual void EnableEncryptEverything() = 0;
-
-  // Returns true if we are currently set to encrypt all the sync data.
-  virtual bool IsEncryptEverythingEnabled() const = 0;
-
-  // Asynchronously sets the passphrase to |passphrase| for encryption. |type|
-  // specifies whether the passphrase is a custom passphrase or the GAIA
-  // password being reused as a passphrase.
-  // TODO(atwilson): Change this so external callers can only set an EXPLICIT
-  // passphrase with this API.
-  virtual void SetEncryptionPassphrase(const std::string& passphrase,
-                                       PassphraseType type) = 0;
-
-  // Asynchronously decrypts pending keys using |passphrase|. Returns false
-  // immediately if the passphrase could not be used to decrypt a locally cached
-  // copy of encrypted keys; returns true otherwise.
-  virtual bool SetDecryptionPassphrase(const std::string& passphrase)
-      WARN_UNUSED_RESULT = 0;
-
-  // Checks whether the Cryptographer is ready to encrypt and decrypt updates
-  // for sensitive data types. Caller must be holding a
-  // syncapi::BaseTransaction to ensure thread safety.
-  virtual bool IsCryptographerReady(
-      const syncer::BaseTransaction* trans) const = 0;
-
-  // TODO(akalin): This is called mostly by ModelAssociators and
-  // tests.  Figure out how to pass the handle to the ModelAssociators
-  // directly, figure out how to expose this to tests, and remove this
-  // function.
-  virtual syncer::UserShare* GetUserShare() const = 0;
-
-  // Returns DeviceInfo provider for the local device.
-  virtual LocalDeviceInfoProvider* GetLocalDeviceInfoProvider() const = 0;
-
-  // Registers a data type controller with the sync service.  This
-  // makes the data type controller available for use, it does not
-  // enable or activate the synchronization of the data type (see
-  // ActivateDataType).  Takes ownership of the pointer.
-  virtual void RegisterDataTypeController(
-      DataTypeController* data_type_controller) = 0;
-
-  // Called to re-enable a type disabled by DisableDatatype(..). Note, this does
-  // not change the preferred state of a datatype, and is not persisted across
-  // restarts.
-  virtual void ReenableDatatype(syncer::ModelType type) = 0;
-
-  // Return sync token status.
-  virtual SyncTokenStatus GetSyncTokenStatus() const = 0;
-
-  // Get a description of the sync status for displaying in the user interface.
-  virtual std::string QuerySyncStatusSummaryString() = 0;
-
-  // Initializes a struct of status indicators with data from the backend.
-  // Returns false if the backend was not available for querying; in that case
-  // the struct will be filled with default data.
-  virtual bool QueryDetailedSyncStatus(syncer::SyncStatus* result) = 0;
-
-  // Returns a user-friendly string form of last synced time (in minutes).
-  virtual base::string16 GetLastSyncedTimeString() const = 0;
-
-  // Returns a human readable string describing backend initialization state.
-  virtual std::string GetBackendInitializationStateString() const = 0;
-
-  virtual syncer::sessions::SyncSessionSnapshot GetLastSessionSnapshot()
-      const = 0;
-
-  // Returns a ListValue indicating the status of all registered types.
-  //
-  // The format is:
-  // [ {"name": <name>, "value": <value>, "status": <status> }, ... ]
-  // where <name> is a type's name, <value> is a string providing details for
-  // the type's status, and <status> is one of "error", "warning" or "ok"
-  // depending on the type's current status.
-  //
-  // This function is used by about_sync_util.cc to help populate the about:sync
-  // page.  It returns a ListValue rather than a DictionaryValue in part to make
-  // it easier to iterate over its elements when constructing that page.
-  virtual base::Value* GetTypeStatusMap() const = 0;
-
-  virtual const GURL& sync_service_url() const = 0;
-
-  virtual std::string unrecoverable_error_message() const = 0;
-  virtual tracked_objects::Location unrecoverable_error_location() const = 0;
-
-  virtual void AddProtocolEventObserver(
-      browser_sync::ProtocolEventObserver* observer) = 0;
-  virtual void RemoveProtocolEventObserver(
-      browser_sync::ProtocolEventObserver* observer) = 0;
-
-  virtual void AddTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) = 0;
-  virtual void RemoveTypeDebugInfoObserver(
-      syncer::TypeDebugInfoObserver* observer) = 0;
-
-  // Returns a weak pointer to the service's JsController.
-  virtual base::WeakPtr<syncer::JsController> GetJsController() = 0;
-
-  // Asynchronously fetches base::Value representations of all sync nodes and
-  // returns them to the specified callback on this thread.
-  //
-  // These requests can live a long time and return when you least expect it.
-  // For safety, the callback should be bound to some sort of WeakPtr<> or
-  // scoped_refptr<>.
-  virtual void GetAllNodes(
-      const base::Callback<void(std::unique_ptr<base::ListValue>)>&
-          callback) = 0;
-
- protected:
-  SyncService() {}
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(SyncService);
-};
-
-}  // namespace sync_driver
-
-#endif  // COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_H_