Basic implementation of the Sync C++ fake server

sync/test/fake_server/fake_server.cc

+// Copyright 2013 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.
+
+#include "sync/test/fake_server/fake_server.h"
+
+#include <limits>
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/strings/string_number_conversions.h"
+#include "sync/internal_api/public/base/model_type.h"
+#include "sync/protocol/sync.pb.h"
+
+using std::string;
+
+// The parent tag for childen of the root node.
+static const char kRootParentTag[] = "0";
+
+namespace syncer {
+namespace {
+
+// A filter used during GetUpdates calls to determine what information to
+// send back to the client. There is a 1:1 correspondence between any given
+// GetUpdates call and an UpdateSieve instance.
+class UpdateSieve {
+ public:
+  ~UpdateSieve() { }
+
+  // Factory method for creating an UpdateSieve.
+  static scoped_ptr<UpdateSieve> Create(
+      const sync_pb::GetUpdatesMessage& get_updates_message);
+
+  // Sets the progress markers in |get_updates_response| given the progress
+  // markers from the original GetUpdatesMessage and |new_version| (the latest
+  // version in the entries sent back).
+  void UpdateProgressMarkers(
+      int64 new_version,
+      sync_pb::GetUpdatesResponse* get_updates_response) const {
+    ModelTypeToVersionMap::const_iterator it;
+    for (it = request_from_version_.begin(); it != request_from_version_.end();
+         ++it) {
+      sync_pb::DataTypeProgressMarker* new_marker =
+          get_updates_response->add_new_progress_marker();
+      new_marker->set_data_type_id(
+          GetSpecificsFieldNumberFromModelType(it->first));
+
+      int64 version = std::max(new_version, it->second);
+      new_marker->set_token(base::Int64ToString(version));
+    }
+  }
+
+  // Determines whether the server should send |entity| to the client based
+  // on its type and version.
+  bool ClientWantsItem(const sync_pb::SyncEntity& entity) const {
+    ModelTypeToVersionMap::const_iterator it =
+        request_from_version_.find(GetModelType(entity));
+
+    return it == request_from_version_.end() ?
+        false : it->second < entity.version();
+  }
+
+  // Returns the mininum version seen across all types.
+  int64 GetMinVersion() const {
+    return min_version_;
+  }
+
+  // Returns the data type IDs of types being synced for the first time.
+  std::vector<ModelType> GetFirstTimeTypes() const {
+    std::vector<ModelType> types;
+
+    ModelTypeToVersionMap::const_iterator it;
+    for (it = request_from_version_.begin(); it != request_from_version_.end();
+         ++it) {
+      if (it->second == 0)
+        types.push_back(it->first);
+    }
+
+    return types;
+  }
+
+ private:
+  typedef std::map<ModelType, int64> ModelTypeToVersionMap;
+
+  // Creates an UpdateSieve.
+  UpdateSieve(const ModelTypeToVersionMap request_from_version,
+              const int64 min_version)
+      : request_from_version_(request_from_version),
+        min_version_(min_version) { }
+
+  // Maps data type IDs to the latest version seen for that type.
+  const ModelTypeToVersionMap request_from_version_;
+
+  // The minimum version seen among all data types.
+  const int min_version_;
+};
+
+scoped_ptr<UpdateSieve> UpdateSieve::Create(
+    const sync_pb::GetUpdatesMessage& get_updates_message) {
+  DCHECK_GT(get_updates_message.from_progress_marker_size(), 0);
+
+  UpdateSieve::ModelTypeToVersionMap request_from_version;
+  int64 min_version = std::numeric_limits<int64>::max();
+  for (int i = 0; i < get_updates_message.from_progress_marker_size(); i++) {
+    sync_pb::DataTypeProgressMarker marker =
+        get_updates_message.from_progress_marker(i);
+
+    int64 version;
+    if (!marker.has_token() || marker.token().empty()) {
+      // Initialize the version on the first request for this type.
+      version = 0;
+    } else {
+      DCHECK(base::StringToInt64(marker.token(), &version));
+    }
+
+    ModelType model_type = GetModelTypeFromSpecificsFieldNumber(
+        marker.data_type_id());
+    request_from_version[model_type] = version;
+
+    if (version < min_version)
+      min_version = version;
+  }
+
+  return scoped_ptr<UpdateSieve>(
+      new UpdateSieve(request_from_version, min_version));
+}
+
+}  // namespace
+
+FakeServer::FakeServer() : version_(0), birthday_("1234567890") {
+  keystore_keys_.push_back("1111111111111111");
+}
+
+FakeServer::~FakeServer() { }
+
+void FakeServer::CreateDefaultPermanentItems(
+    const std::vector<ModelType>& first_time_types) {
+  for (std::vector<ModelType>::const_iterator it = first_time_types.begin();
+       it != first_time_types.end(); ++it) {
+    if (!ModelTypeSet::All().Has(*it)) {
+      NOTREACHED() << "An unexpected ModelType was encountered.";
+    }
+
+    ModelType model_type = *it;
+    CreateSyncEntity(model_type,
+                     ModelTypeToRootTag(model_type),
+                     ModelTypeToString(model_type),
+                     kRootParentTag);
+
+    if (model_type == BOOKMARKS) {
+      CreateSyncEntity(BOOKMARKS,
+                       "bookmark_bar",
+                       "Bookmark Bar",
+                       ModelTypeToRootTag(BOOKMARKS));
+      CreateSyncEntity(BOOKMARKS,
+                       "other_bookmarks",
+                       "Other Bookmarks",
+                       ModelTypeToRootTag(BOOKMARKS));
+    }
+  }
+
+
+  // TODO(pvalenzuela): Create the mobile bookmarks folder when the fake server
+  // is used by mobile tests.
+}
+
+void FakeServer::CreateSyncEntity(ModelType model_type,
+                                  const std::string& id,
+                                  const std::string& name,
+                                  const std::string& parent_tag) {
+  DCHECK(!id.empty());
+  DCHECK(!name.empty());
+  DCHECK(!parent_tag.empty());
+
+  sync_pb::SyncEntity entity;
+  entity.set_id_string(id);
+  entity.set_non_unique_name(name);
+  entity.set_name(name);
+  entity.set_server_defined_unique_tag(id);
+  entity.set_folder(true);
+  entity.set_deleted(false);
+
+  entity.set_parent_id_string(parent_tag);
+
+  if (parent_tag != kRootParentTag && model_type == BOOKMARKS) {
+    // Use a dummy value here.
+    entity.set_position_in_parent(1337);
+  }
+
+  sync_pb::EntitySpecifics* specifics = entity.mutable_specifics();
+  AddDefaultFieldValue(model_type, specifics);
+
+  SaveEntity(entity);
+}
+
+void FakeServer::SaveEntity(sync_pb::SyncEntity entity) {
+  version_++;
+  entity.set_version(version_);
+  entity.set_sync_timestamp(version_);
+
+  sync_pb::SyncEntity original_entity = entities_[entity.id_string()];
+  entity.set_originator_cache_guid(original_entity.originator_cache_guid());
+  entity.set_originator_client_item_id(
+      original_entity.originator_client_item_id());
+
+  entities_[entity.id_string()] = entity;
+}
+
+int FakeServer::HandleCommand(string request,
+                              int* response_code,
+                              string* response) {
+  sync_pb::ClientToServerMessage message;
+  DCHECK(message.ParseFromString(request));
+
+  sync_pb::ClientToServerResponse response_proto;
+  switch (message.message_contents()) {
+    case sync_pb::ClientToServerMessage::GET_UPDATES:
+      response_proto = HandleGetUpdatesRequest(message);
+      break;
+    case sync_pb::ClientToServerMessage::COMMIT:
+      response_proto = HandleCommitRequest(message);
+      break;
+    default:
+      // Any nonzero int will indicate a failure here. This one happens to
+      // be net::ERR_NOT_IMPLEMENTED.
+      return -11;
+  }
+
+  *response_code = 200;
+  *response = response_proto.SerializeAsString();
+  return 0;
+}
+
+bool SyncEntityVersionComparator(const sync_pb::SyncEntity& first,
+                                 const sync_pb::SyncEntity& second) {
+  return first.version() < second.version();
+}
+
+sync_pb::ClientToServerResponse FakeServer::HandleGetUpdatesRequest(
+    const sync_pb::ClientToServerMessage& message) {
+  sync_pb::ClientToServerResponse response;
+  response.set_error_code(sync_pb::SyncEnums::SUCCESS);
+  response.set_store_birthday(birthday_);
+
+  sync_pb::GetUpdatesResponse* get_updates_response =
+      response.mutable_get_updates();
+  // TODO(pvalenzuela): Implement batching instead of sending all information
+  // at once.
+  get_updates_response->set_changes_remaining(0);
+
+  scoped_ptr<UpdateSieve> sieve = UpdateSieve::Create(message.get_updates());
+  CreateDefaultPermanentItems(sieve->GetFirstTimeTypes());
+
+  int64 min_version = sieve->GetMinVersion();
+
+  bool send_encryption_keys_based_on_nigori = false;
+  int64 max_response_version = 0;
+  for (EntityMap::iterator it = entities_.begin(); it != entities_.end();
+       ++it) {
+    sync_pb::SyncEntity entity = it->second;
+    if (entity.version() > min_version && sieve->ClientWantsItem(entity)) {
+      sync_pb::SyncEntity* response_entity =
+          get_updates_response->add_entries();
+      response_entity->CopyFrom(entity);
+      max_response_version = std::max(max_response_version,
+                                      response_entity->version());
+
+      if (response_entity->name() == ModelTypeToString(NIGORI)) {
+        send_encryption_keys_based_on_nigori =
+            response_entity->specifics().nigori().passphrase_type() ==
+                sync_pb::NigoriSpecifics::KEYSTORE_PASSPHRASE;
+      }
+    }
+  }
+
+  if (send_encryption_keys_based_on_nigori ||
+      message.get_updates().need_encryption_key()) {
+    for (std::vector<std::string>::iterator it = keystore_keys_.begin();
+         it != keystore_keys_.end(); ++it) {
+      get_updates_response->add_encryption_keys(*it);
+    }
+  }
+
+  sieve->UpdateProgressMarkers(max_response_version, get_updates_response);
+
+  return response;
+}
+
+sync_pb::SyncEntity FakeServer::CommitEntity(sync_pb::SyncEntity entity,
+                                             string guid) {
+  // TODO(pvalenzuela): Implement this. Right now this method cheats and
+  // doesn't actually commit.
+  return entity;
+}
+
+sync_pb::ClientToServerResponse FakeServer::HandleCommitRequest(
+    const sync_pb::ClientToServerMessage& message) {
+  sync_pb::ClientToServerResponse response;
+  response.set_error_code(sync_pb::SyncEnums::SUCCESS);
+  response.set_store_birthday(birthday_);
+
+  sync_pb::CommitMessage commit = message.commit();
+  string guid = commit.cache_guid();
+
+  sync_pb::CommitResponse* commit_response = response.mutable_commit();
+
+  ::google::protobuf::RepeatedPtrField<sync_pb::SyncEntity>::const_iterator it;
+  for (it = commit.entries().begin(); it != commit.entries().end(); ++it) {
+    sync_pb::CommitResponse_EntryResponse* entry_response =
+        commit_response->add_entryresponse();
+
+    sync_pb::SyncEntity server_entity = CommitEntity(*it, guid);
+
+    entry_response->set_id_string(server_entity.id_string());
+    entry_response->set_response_type(sync_pb::CommitResponse::SUCCESS);
+    entry_response->set_version(it->version() + 1);
+  }
+
+  return response;
+}
+
+}  // namespace syncer