sync: move internal_api components used by chrome/browser into internal_api/public

sync/internal_api/sync_manager.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 SYNC_INTERNAL_API_SYNC_MANAGER_H_
-#define SYNC_INTERNAL_API_SYNC_MANAGER_H_
-
-#include <string>
-#include <vector>
-
-#include "base/basictypes.h"
-#include "base/callback_forward.h"
-#include "base/file_path.h"
-#include "base/memory/ref_counted.h"
-#include "base/task_runner.h"
-#include "base/threading/thread_checker.h"
-#include "base/time.h"
-#include "sync/internal_api/change_record.h"
-#include "sync/internal_api/configure_reason.h"
-#include "sync/internal_api/public/engine/model_safe_worker.h"
-#include "sync/internal_api/public/engine/sync_status.h"
-#include "sync/internal_api/public/syncable/model_type.h"
-#include "sync/protocol/sync_protocol_error.h"
-#include "sync/util/report_unrecoverable_error_function.h"
-#include "sync/util/unrecoverable_error_handler.h"
-#include "sync/util/weak_handle.h"
-
-namespace browser_sync {
-struct ConfigurationParams;
-class Encryptor;
-struct Experiments;
-class ExtensionsActivityMonitor;
-class JsBackend;
-class JsEventHandler;
-class SyncScheduler;
-
-namespace sessions {
-class SyncSessionSnapshot;
-}  // namespace sessions
-}  // namespace browser_sync
-
-namespace sync_notifier {
-class SyncNotifier;
-}  // namespace sync_notifier
-
-namespace sync_pb {
-class EncryptedData;
-}  // namespace sync_pb
-
-namespace sync_api {
-
-class BaseTransaction;
-class HttpPostProviderFactory;
-struct UserShare;
-
-// Used by SyncManager::OnConnectionStatusChange().
-enum ConnectionStatus {
-  CONNECTION_OK,
-  CONNECTION_AUTH_ERROR,
-  CONNECTION_SERVER_ERROR
-};
-
-// Reasons due to which browser_sync::Cryptographer might require a passphrase.
-enum PassphraseRequiredReason {
-  REASON_PASSPHRASE_NOT_REQUIRED = 0,  // Initial value.
-  REASON_ENCRYPTION = 1,               // The cryptographer requires a
-                                       // passphrase for its first attempt at
-                                       // encryption. Happens only during
-                                       // migration or upgrade.
-  REASON_DECRYPTION = 2,               // The cryptographer requires a
-                                       // passphrase for its first attempt at
-                                       // decryption.
-};
-
-
-// Contains everything needed to talk to and identify a user account.
-struct SyncCredentials {
-  std::string email;
-  std::string sync_token;
-};
-
-// SyncManager encapsulates syncable::Directory and serves as the parent of all
-// other objects in the sync API.  If multiple threads interact with the same
-// local sync repository (i.e. the same sqlite database), they should share a
-// single SyncManager instance.  The caller should typically create one
-// SyncManager for the lifetime of a user session.
-//
-// Unless stated otherwise, all methods of SyncManager should be called on the
-// same thread.
-class SyncManager {
- public:
-  // SyncInternal contains the implementation of SyncManager, while abstracting
-  // internal types from clients of the interface.
-  class SyncInternal;
-
-  // An interface the embedding application implements to be notified
-  // on change events.  Note that these methods may be called on *any*
-  // thread.
-  class ChangeDelegate {
-   public:
-    // Notify the delegate that changes have been applied to the sync model.
-    //
-    // This will be invoked on the same thread as on which ApplyChanges was
-    // called. |changes| is an array of size |change_count|, and contains the
-    // ID of each individual item that was changed. |changes| exists only for
-    // the duration of the call. If items of multiple data types change at
-    // the same time, this method is invoked once per data type and |changes|
-    // is restricted to items of the ModelType indicated by |model_type|.
-    // Because the observer is passed a |trans|, the observer can assume a
-    // read lock on the sync model that will be released after the function
-    // returns.
-    //
-    // The SyncManager constructs |changes| in the following guaranteed order:
-    //
-    // 1. Deletions, from leaves up to parents.
-    // 2. Updates to existing items with synced parents & predecessors.
-    // 3. New items with synced parents & predecessors.
-    // 4. Items with parents & predecessors in |changes|.
-    // 5. Repeat #4 until all items are in |changes|.
-    //
-    // Thus, an implementation of OnChangesApplied should be able to
-    // process the change records in the order without having to worry about
-    // forward dependencies.  But since deletions come before reparent
-    // operations, a delete may temporarily orphan a node that is
-    // updated later in the list.
-    virtual void OnChangesApplied(
-        syncable::ModelType model_type,
-        const BaseTransaction* trans,
-        const ImmutableChangeRecordList& changes) = 0;
-
-    // OnChangesComplete gets called when the TransactionComplete event is
-    // posted (after OnChangesApplied finishes), after the transaction lock
-    // and the change channel mutex are released.
-    //
-    // The purpose of this function is to support processors that require
-    // split-transactions changes. For example, if a model processor wants to
-    // perform blocking I/O due to a change, it should calculate the changes
-    // while holding the transaction lock (from within OnChangesApplied), buffer
-    // those changes, let the transaction fall out of scope, and then commit
-    // those changes from within OnChangesComplete (postponing the blocking
-    // I/O to when it no longer holds any lock).
-    virtual void OnChangesComplete(syncable::ModelType model_type) = 0;
-
-   protected:
-    virtual ~ChangeDelegate();
-  };
-
-  // Like ChangeDelegate, except called only on the sync thread and
-  // not while a transaction is held.  For objects that want to know
-  // when changes happen, but don't need to process them.
-  class ChangeObserver {
-   public:
-    // Ids referred to in |changes| may or may not be in the write
-    // transaction specified by |write_transaction_id|.  If they're
-    // not, that means that the node didn't actually change, but we
-    // marked them as changed for some other reason (e.g., siblings of
-    // re-ordered nodes).
-    //
-    // TODO(sync, long-term): Ideally, ChangeDelegate/Observer would
-    // be passed a transformed version of EntryKernelMutation instead
-    // of a transaction that would have to be used to look up the
-    // changed nodes.  That is, ChangeDelegate::OnChangesApplied()
-    // would still be called under the transaction, but all the needed
-    // data will be passed down.
-    //
-    // Even more ideally, we would have sync semantics such that we'd
-    // be able to apply changes without being under a transaction.
-    // But that's a ways off...
-    virtual void OnChangesApplied(
-        syncable::ModelType model_type,
-        int64 write_transaction_id,
-        const ImmutableChangeRecordList& changes) = 0;
-
-    virtual void OnChangesComplete(syncable::ModelType model_type) = 0;
-
-   protected:
-    virtual ~ChangeObserver();
-  };
-
-  // An interface the embedding application implements to receive
-  // notifications from the SyncManager.  Register an observer via
-  // SyncManager::AddObserver.  All methods are called only on the
-  // sync thread.
-  class Observer {
-   public:
-    // A round-trip sync-cycle took place and the syncer has resolved any
-    // conflicts that may have arisen.
-    virtual void OnSyncCycleCompleted(
-        const browser_sync::sessions::SyncSessionSnapshot& snapshot) = 0;
-
-    // Called when the status of the connection to the sync server has
-    // changed.
-    virtual void OnConnectionStatusChange(ConnectionStatus status) = 0;
-
-    // Called when a new auth token is provided by the sync server.
-    virtual void OnUpdatedToken(const std::string& token) = 0;
-
-    // Called when user interaction is required to obtain a valid passphrase.
-    // - If the passphrase is required for encryption, |reason| will be
-    //   REASON_ENCRYPTION.
-    // - If the passphrase is required for the decryption of data that has
-    //   already been encrypted, |reason| will be REASON_DECRYPTION.
-    // - If the passphrase is required because decryption failed, and a new
-    //   passphrase is required, |reason| will be REASON_SET_PASSPHRASE_FAILED.
-    //
-    // |pending_keys| is a copy of the cryptographer's pending keys, that may be
-    // cached by the frontend for subsequent use by the UI.
-    virtual void OnPassphraseRequired(
-        PassphraseRequiredReason reason,
-        const sync_pb::EncryptedData& pending_keys) = 0;
-
-    // Called when the passphrase provided by the user has been accepted and is
-    // now used to encrypt sync data.
-    virtual void OnPassphraseAccepted() = 0;
-
-    // |bootstrap_token| is an opaque base64 encoded representation of the key
-    // generated by the current passphrase, and is provided to the observer for
-    // persistence purposes and use in a future initialization of sync (e.g.
-    // after restart). The boostrap token will always be derived from the most
-    // recent GAIA password (for accounts with implicit passphrases), even if
-    // the data is still encrypted with an older GAIA password. For accounts
-    // with explicit passphrases, it will be the most recently seen custom
-    // passphrase.
-    virtual void OnBootstrapTokenUpdated(
-        const std::string& bootstrap_token) = 0;
-
-    // Called when initialization is complete to the point that SyncManager can
-    // process changes. This does not necessarily mean authentication succeeded
-    // or that the SyncManager is online.
-    // IMPORTANT: Creating any type of transaction before receiving this
-    // notification is illegal!
-    // WARNING: Calling methods on the SyncManager before receiving this
-    // message, unless otherwise specified, produces undefined behavior.
-    //
-    // |js_backend| is what about:sync interacts with.  It can emit
-    // the following events:
-
-    /**
-     * @param {{ enabled: boolean }} details A dictionary containing:
-     *     - enabled: whether or not notifications are enabled.
-     */
-    // function onNotificationStateChange(details);
-
-    /**
-     * @param {{ changedTypes: Array.<string> }} details A dictionary
-     *     containing:
-     *     - changedTypes: a list of types (as strings) for which there
-             are new updates.
-     */
-    // function onIncomingNotification(details);
-
-    // Also, it responds to the following messages (all other messages
-    // are ignored):
-
-    /**
-     * Gets the current notification state.
-     *
-     * @param {function(boolean)} callback Called with whether or not
-     *     notifications are enabled.
-     */
-    // function getNotificationState(callback);
-
-    /**
-     * Gets details about the root node.
-     *
-     * @param {function(!Object)} callback Called with details about the
-     *     root node.
-     */
-    // TODO(akalin): Change this to getRootNodeId or eliminate it
-    // entirely.
-    // function getRootNodeDetails(callback);
-
-    /**
-     * Gets summary information for a list of ids.
-     *
-     * @param {Array.<string>} idList List of 64-bit ids in decimal
-     *     string form.
-     * @param {Array.<{id: string, title: string, isFolder: boolean}>}
-     * callback Called with summaries for the nodes in idList that
-     *     exist.
-     */
-    // function getNodeSummariesById(idList, callback);
-
-    /**
-     * Gets detailed information for a list of ids.
-     *
-     * @param {Array.<string>} idList List of 64-bit ids in decimal
-     *     string form.
-     * @param {Array.<!Object>} callback Called with detailed
-     *     information for the nodes in idList that exist.
-     */
-    // function getNodeDetailsById(idList, callback);
-
-    /**
-     * Gets child ids for a given id.
-     *
-     * @param {string} id 64-bit id in decimal string form of the parent
-     *     node.
-     * @param {Array.<string>} callback Called with the (possibly empty)
-     *     list of child ids.
-     */
-    // function getChildNodeIds(id);
-
-    virtual void OnInitializationComplete(
-        const browser_sync::WeakHandle<browser_sync::JsBackend>&
-            js_backend, bool success) = 0;
-
-    // We are no longer permitted to communicate with the server. Sync should
-    // be disabled and state cleaned up at once.  This can happen for a number
-    // of reasons, e.g. swapping from a test instance to production, or a
-    // global stop syncing operation has wiped the store.
-    virtual void OnStopSyncingPermanently() = 0;
-
-    // After a request to clear server data, these callbacks are invoked to
-    // indicate success or failure.
-    virtual void OnClearServerDataSucceeded() = 0;
-    virtual void OnClearServerDataFailed() = 0;
-
-    // Called when the set of encrypted types or the encrypt
-    // everything flag has been changed.  Note that encryption isn't
-    // complete until the OnEncryptionComplete() notification has been
-    // sent (see below).
-    //
-    // |encrypted_types| will always be a superset of
-    // Cryptographer::SensitiveTypes().  If |encrypt_everything| is
-    // true, |encrypted_types| will be the set of all known types.
-    //
-    // Until this function is called, observers can assume that the
-    // set of encrypted types is Cryptographer::SensitiveTypes() and
-    // that the encrypt everything flag is false.
-    //
-    // Called from within a transaction.
-    virtual void OnEncryptedTypesChanged(
-        syncable::ModelTypeSet encrypted_types,
-        bool encrypt_everything) = 0;
-
-    // Called after we finish encrypting the current set of encrypted
-    // types.
-    //
-    // Called from within a transaction.
-    virtual void OnEncryptionComplete() = 0;
-
-    virtual void OnActionableError(
-        const browser_sync::SyncProtocolError& sync_protocol_error) = 0;
-
-   protected:
-    virtual ~Observer();
-  };
-
-  enum TestingMode {
-    NON_TEST,
-    TEST_ON_DISK,
-    TEST_IN_MEMORY,
-  };
-
-  // Create an uninitialized SyncManager.  Callers must Init() before using.
-  explicit SyncManager(const std::string& name);
-  virtual ~SyncManager();
-
-  // Initialize the sync manager.  |database_location| specifies the path of
-  // the directory in which to locate a sqlite repository storing the syncer
-  // backend state. Initialization will open the database, or create it if it
-  // does not already exist. Returns false on failure.
-  // |event_handler| is the JsEventHandler used to propagate events to
-  // chrome://sync-internals.  |event_handler| may be uninitialized.
-  // |sync_server_and_path| and |sync_server_port| represent the Chrome sync
-  // server to use, and |use_ssl| specifies whether to communicate securely;
-  // the default is false.
-  // |blocking_task_runner| is a TaskRunner to be used for tasks that
-  // may block on disk I/O.
-  // |post_factory| will be owned internally and used to create
-  // instances of an HttpPostProvider.
-  // |model_safe_worker| ownership is given to the SyncManager.
-  // |user_agent| is a 7-bit ASCII string suitable for use as the User-Agent
-  // HTTP header. Used internally when collecting stats to classify clients.
-  // |sync_notifier| is owned and used to listen for notifications.
-  // |report_unrecoverable_error_function| may be NULL.
-  bool Init(const FilePath& database_location,
-            const browser_sync::WeakHandle<browser_sync::JsEventHandler>&
-                event_handler,
-            const std::string& sync_server_and_path,
-            int sync_server_port,
-            bool use_ssl,
-            const scoped_refptr<base::TaskRunner>& blocking_task_runner,
-            HttpPostProviderFactory* post_factory,
-            const browser_sync::ModelSafeRoutingInfo& model_safe_routing_info,
-            const std::vector<browser_sync::ModelSafeWorker*>& workers,
-            browser_sync::ExtensionsActivityMonitor*
-                extensions_activity_monitor,
-            ChangeDelegate* change_delegate,
-            const std::string& user_agent,
-            const SyncCredentials& credentials,
-            sync_notifier::SyncNotifier* sync_notifier,
-            const std::string& restored_key_for_bootstrapping,
-            TestingMode testing_mode,
-            browser_sync::Encryptor* encryptor,
-            browser_sync::UnrecoverableErrorHandler*
-                unrecoverable_error_handler,
-            browser_sync::ReportUnrecoverableErrorFunction
-                report_unrecoverable_error_function);
-
-  // Throw an unrecoverable error from a transaction (mostly used for
-  // testing).
-  void ThrowUnrecoverableError();
-
-  // Returns the set of types for which we have stored some sync data.
-  syncable::ModelTypeSet InitialSyncEndedTypes();
-
-  // Update tokens that we're using in Sync. Email must stay the same.
-  void UpdateCredentials(const SyncCredentials& credentials);
-
-  // Called when the user disables or enables a sync type.
-  void UpdateEnabledTypes(const syncable::ModelTypeSet& enabled_types);
-
-  // Put the syncer in normal mode ready to perform nudges and polls.
-  void StartSyncingNormally(
-      const browser_sync::ModelSafeRoutingInfo& routing_info);
-
-  // Attempts to re-encrypt encrypted data types using the passphrase provided.
-  // Notifies observers of the result of the operation via OnPassphraseAccepted
-  // or OnPassphraseRequired, updates the nigori node, and does re-encryption as
-  // appropriate. If an explicit password has been set previously, we drop
-  // subsequent requests to set a passphrase. If the cryptographer has pending
-  // keys, and a new implicit passphrase is provided, we try decrypting the
-  // pending keys with it, and if that fails, we cache the passphrase for
-  // re-encryption once the pending keys are decrypted.
-  void SetEncryptionPassphrase(const std::string& passphrase, bool is_explicit);
-
-  // Provides a passphrase for decrypting the user's existing sync data.
-  // Notifies observers of the result of the operation via OnPassphraseAccepted
-  // or OnPassphraseRequired, updates the nigori node, and does re-encryption as
-  // appropriate if there is a previously cached encryption passphrase. It is an
-  // error to call this when we don't have pending keys.
-  void SetDecryptionPassphrase(const std::string& passphrase);
-
-  // Request a clearing of all data on the server
-  void RequestClearServerData();
-
-  // Switches the mode of operation to CONFIGURATION_MODE and performs
-  // any configuration tasks needed as determined by the params. Once complete,
-  // syncer will remain in CONFIGURATION_MODE until StartSyncingNormally is
-  // called.
-  // |ready_task| is invoked when the configuration completes.
-  // |retry_task| is invoked if the configuration job could not immediately
-  //              execute. |ready_task| will still be called when it eventually
-  //              does finish.
-  void ConfigureSyncer(
-      ConfigureReason reason,
-      const syncable::ModelTypeSet& types_to_config,
-      const browser_sync::ModelSafeRoutingInfo& new_routing_info,
-      const base::Closure& ready_task,
-      const base::Closure& retry_task);
-
-  // Adds a listener to be notified of sync events.
-  // NOTE: It is OK (in fact, it's probably a good idea) to call this before
-  // having received OnInitializationCompleted.
-  void AddObserver(Observer* observer);
-
-  // Remove the given observer.  Make sure to call this if the
-  // Observer is being destroyed so the SyncManager doesn't
-  // potentially dereference garbage.
-  void RemoveObserver(Observer* observer);
-
-  // Status-related getter.  May be called on any thread.
-  SyncStatus GetDetailedStatus() const;
-
-  // Whether or not the Nigori node is encrypted using an explicit passphrase.
-  // May be called on any thread.
-  bool IsUsingExplicitPassphrase();
-
-  // Call periodically from a database-safe thread to persist recent changes
-  // to the syncapi model.
-  void SaveChanges();
-
-  // Initiates shutdown of various components in the sync engine.  Must be
-  // called from the main thread to allow preempting ongoing tasks on the sync
-  // loop (that may be blocked on I/O).  The semantics of |callback| are the
-  // same as with StartConfigurationMode. If provided and a scheduler / sync
-  // loop exists, it will be invoked from the sync loop by the scheduler to
-  // notify that all work has been flushed + cancelled, and it is idle.
-  // If no scheduler exists, the callback is run immediately (from the loop
-  // this was created on, which is the sync loop), as sync is effectively
-  // stopped.
-  void StopSyncingForShutdown(const base::Closure& callback);
-
-  // Issue a final SaveChanges, and close sqlite handles.
-  void ShutdownOnSyncThread();
-
-  // May be called from any thread.
-  UserShare* GetUserShare() const;
-
-  // Inform the cryptographer of the most recent passphrase and set of
-  // encrypted types (from nigori node), then ensure all data that
-  // needs encryption is encrypted with the appropriate passphrase.
-  //
-  // May trigger OnPassphraseRequired().  Otherwise, it will trigger
-  // OnEncryptedTypesChanged() if necessary (see comments for
-  // OnEncryptedTypesChanged()), and then OnEncryptionComplete().
-  //
-  // Also updates or adds device information to the nigori node.
-  //
-  // Note: opens a transaction, so must only be called after syncapi
-  // has been initialized.
-  void RefreshNigori(const std::string& chrome_version,
-                     const base::Closure& done_callback);
-
-  // Enable encryption of all sync data. Once enabled, it can never be
-  // disabled without clearing the server data.
-  //
-  // This will trigger OnEncryptedTypesChanged() if necessary (see
-  // comments for OnEncryptedTypesChanged()).  It then may trigger
-  // OnPassphraseRequired(), but otherwise it will trigger
-  // OnEncryptionComplete().
-  void EnableEncryptEverything();
-
-  // Returns true if we are currently encrypting all sync data.  May
-  // be called on any thread.
-  bool EncryptEverythingEnabledForTest() const;
-
-  // Gets the set of encrypted types from the cryptographer
-  // Note: opens a transaction.  May be called from any thread.
-  syncable::ModelTypeSet GetEncryptedDataTypesForTest() const;
-
-  // Reads the nigori node to determine if any experimental features should
-  // be enabled.
-  // Note: opens a transaction.  May be called on any thread.
-  bool ReceivedExperiment(browser_sync::Experiments* experiments) const;
-
-  // Uses a read-only transaction to determine if the directory being synced has
-  // any remaining unsynced items.  May be called on any thread.
-  bool HasUnsyncedItems() const;
-
-  // Functions used for testing.
-
-  void TriggerOnNotificationStateChangeForTest(
-      bool notifications_enabled);
-
-  void TriggerOnIncomingNotificationForTest(
-      syncable::ModelTypeSet model_types);
-
-  static const int kDefaultNudgeDelayMilliseconds;
-  static const int kPreferencesNudgeDelayMilliseconds;
-  static const int kPiggybackNudgeDelay;
-
-  static const FilePath::CharType kSyncDatabaseFilename[];
-
- private:
-  friend class SyncManagerTest;
-  FRIEND_TEST_ALL_PREFIXES(SyncManagerTest, NudgeDelayTest);
-
-  // For unit tests.
-  base::TimeDelta GetNudgeDelayTimeDelta(const syncable::ModelType& model_type);
-
-  // Set the internal scheduler for testing purposes.
-  // TODO(sync): Use dependency injection instead. crbug.com/133061
-  void SetSyncSchedulerForTest(
-      scoped_ptr<browser_sync::SyncScheduler> scheduler);
-
-  base::ThreadChecker thread_checker_;
-
-  // An opaque pointer to the nested private class.
-  SyncInternal* data_;
-
-  DISALLOW_COPY_AND_ASSIGN(SyncManager);
-};
-
-bool InitialSyncEndedForTypes(syncable::ModelTypeSet types, UserShare* share);
-
-syncable::ModelTypeSet GetTypesWithEmptyProgressMarkerToken(
-    syncable::ModelTypeSet types,
-    sync_api::UserShare* share);
-
-const char* ConnectionStatusToString(ConnectionStatus status);
-
-// Returns the string representation of a PassphraseRequiredReason value.
-const char* PassphraseRequiredReasonToString(PassphraseRequiredReason reason);
-
-}  // namespace sync_api
-
-#endif  // SYNC_INTERNAL_API_SYNC_MANAGER_H_