sync/engine/syncer_proto_util.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef SYNC_ENGINE_SYNCER_PROTO_UTIL_H_
   6 #define SYNC_ENGINE_SYNCER_PROTO_UTIL_H_
   7
   8 #include <string>
   9
  10 #include "base/gtest_prod_util.h"
  11 #include "base/time.h"
  12 #include "sync/internal_api/public/base/model_type.h"
  13 #include "sync/internal_api/public/util/syncer_error.h"
  14 #include "sync/sessions/sync_session.h"
  15 #include "sync/syncable/blob.h"
  16
  17 namespace sync_pb {
  18 class ClientToServerMessage;
  19 class ClientToServerResponse;
  20 class CommitResponse_EntryResponse;
  21 class EntitySpecifics;
  22 class SyncEntity;
  23 }
  24
  25 namespace syncer {
  26
  27 class ThrottledDataTypeTracker;
  28 class ServerConnectionManager;
  29
  30 namespace sessions {
  31 class SyncProtocolError;
  32 class SyncSessionContext;
  33 }
  34
  35 namespace syncable {
  36 class Directory;
  37 class Entry;
  38 }
  39
  40 class SyncerProtoUtil {
  41  public:
  42   // Posts the given message and fills the buffer with the returned value.
  43   // Returns true on success.  Also handles store birthday verification: will
  44   // produce a SyncError if the birthday is incorrect.
  45   // NOTE: This will add all fields that must be sent on every request, which
  46   // includes store birthday, protocol version, client chips, api keys, etc.
  47   static SyncerError PostClientToServerMessage(
  48       sync_pb::ClientToServerMessage* msg,
  49       sync_pb::ClientToServerResponse* response,
  50       sessions::SyncSession* session);
  51
  52   // Compares a syncable Entry to SyncEntity, returns true iff the data is
  53   // identical.
  54   //
  55   // TODO(sync): The places where this function is used are arguable big causes
  56   // of the fragility, because there's a tendency to freak out the moment the
  57   // local and server values diverge. However, this almost always indicates a
  58   // sync bug somewhere earlier in the sync cycle.
  59   static bool Compare(const syncable::Entry& local_entry,
  60                       const sync_pb::SyncEntity& server_entry);
  61
  62   // Utility methods for converting between syncable::Blobs and protobuf byte
  63   // fields.
  64   static void CopyProtoBytesIntoBlob(const std::string& proto_bytes,
  65                                      syncable::Blob* blob);
  66   static bool ProtoBytesEqualsBlob(const std::string& proto_bytes,
  67                                    const syncable::Blob& blob);
  68   static void CopyBlobIntoProtoBytes(const syncable::Blob& blob,
  69                                      std::string* proto_bytes);
  70
  71   // Extract the name field from a sync entity.
  72   static const std::string& NameFromSyncEntity(
  73       const sync_pb::SyncEntity& entry);
  74
  75   // Extract the name field from a commit entry response.
  76   static const std::string& NameFromCommitEntryResponse(
  77       const sync_pb::CommitResponse_EntryResponse& entry);
  78
  79   // Persist the bag of chips if it is present in the response.
  80   static void PersistBagOfChips(
  81       syncable::Directory* dir,
  82       const sync_pb::ClientToServerResponse& response);
  83
  84   // EntitySpecifics is used as a filter for the GetUpdates message to tell
  85   // the server which datatypes to send back.  This adds a datatype so that
  86   // it's included in the filter.
  87   static void AddToEntitySpecificDatatypesFilter(ModelType datatype,
  88       sync_pb::EntitySpecifics* filter);
  89
  90   // Get a debug string representation of the client to server response.
  91   static std::string ClientToServerResponseDebugString(
  92       const sync_pb::ClientToServerResponse& response);
  93
  94   // Get update contents as a string. Intended for logging, and intended
  95   // to have a smaller footprint than the protobuf's built-in pretty printer.
  96   static std::string SyncEntityDebugString(const sync_pb::SyncEntity& entry);
  97
  98   // Pull the birthday from the dir and put it into the msg.
  99   static void AddRequestBirthday(syncable::Directory* dir,
 100                                  sync_pb::ClientToServerMessage* msg);
 101
 102   // Pull the bag of chips from the dir and put it into the msg.
 103   static void AddBagOfChips(syncable::Directory* dir,
 104                             sync_pb::ClientToServerMessage* msg);
 105
 106
 107   // Set the protocol version field in the outgoing message.
 108   static void SetProtocolVersion(sync_pb::ClientToServerMessage* msg);
 109
 110  private:
 111   SyncerProtoUtil() {}
 112
 113   // Helper functions for PostClientToServerMessage.
 114
 115   // Verifies the store birthday, alerting/resetting as appropriate if there's a
 116   // mismatch. Return false if the syncer should be stuck.
 117   static bool VerifyResponseBirthday(syncable::Directory* dir,
 118       const sync_pb::ClientToServerResponse* response);
 119
 120   // Builds and sends a SyncEngineEvent to begin migration for types (specified
 121   // in notification).
 122   static void HandleMigrationDoneResponse(
 123       const sync_pb::ClientToServerResponse* response,
 124       sessions::SyncSession* session);
 125
 126   // Post the message using the scm, and do some processing on the returned
 127   // headers. Decode the server response.
 128   static bool PostAndProcessHeaders(ServerConnectionManager* scm,
 129                                     sessions::SyncSession* session,
 130                                     const sync_pb::ClientToServerMessage& msg,
 131                                     sync_pb::ClientToServerResponse* response);
 132
 133   static base::TimeDelta GetThrottleDelay(
 134       const sync_pb::ClientToServerResponse& response);
 135
 136   static void HandleThrottleError(
 137       const SyncProtocolError& error,
 138       const base::TimeTicks& throttled_until,
 139       ThrottledDataTypeTracker* tracker,
 140       sessions::SyncSession::Delegate* delegate);
 141
 142   friend class SyncerProtoUtilTest;
 143   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, AddRequestBirthday);
 144   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, PostAndProcessHeaders);
 145   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, VerifyResponseBirthday);
 146   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, HandleThrottlingNoDatatypes);
 147   FRIEND_TEST_ALL_PREFIXES(SyncerProtoUtilTest, HandleThrottlingWithDatatypes);
 148
 149   DISALLOW_COPY_AND_ASSIGN(SyncerProtoUtil);
 150 };
 151
 152 }  // namespace syncer
 153
 154 #endif  // SYNC_ENGINE_SYNCER_PROTO_UTIL_H_