components/gcm_driver/gcm_account_mapper.cc - chromium/src - Git at Google

 // Copyright 2014 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 "components/gcm_driver/gcm_account_mapper.h"

 #include <utility>

 #include "base/bind.h"
 #include "base/guid.h"
 #include "base/time/clock.h"
 #include "base/time/default_clock.h"
 #include "components/gcm_driver/gcm_driver_desktop.h"
 #include "google_apis/gcm/engine/gcm_store.h"

 namespace gcm {

 namespace {

 const char kGCMAccountMapperSenderId[] = "745476177629";
 const char kGCMAccountMapperSendTo[] = "google.com";
 const int kGCMAddMappingMessageTTL = 30 * 60;  // 0.5 hours in seconds.
 const int kGCMRemoveMappingMessageTTL = 24 * 60 * 60;  // 1 day in seconds.
 const int kGCMUpdateIntervalHours = 24;
 // Because adding an account mapping dependents on a fresh OAuth2 token, we
 // allow the update to happen earlier than update due time, if it is within
 // the early start time to take advantage of that token.
 const int kGCMUpdateEarlyStartHours = 6;
 const char kRegistrationIdMessgaeKey[] = "id";
 const char kTokenMessageKey[] = "t";
 const char kAccountMessageKey[] = "a";
 const char kRemoveAccountKey[] = "r";
 const char kRemoveAccountValue[] = "1";
 // Use to handle send to Gaia ID scenario:
 const char kGCMSendToGaiaIdAppIdKey[] = "gcmb";


 std::string GenerateMessageID() {
   return base::GenerateGUID();
 }

 }  // namespace

 const char kGCMAccountMapperAppId[] = "com.google.android.gms";

 GCMAccountMapper::GCMAccountMapper(GCMDriver* gcm_driver)
     : gcm_driver_(gcm_driver),
       clock_(base::DefaultClock::GetInstance()),
       initialized_(false),
       weak_ptr_factory_(this) {}

 GCMAccountMapper::~GCMAccountMapper() {
 }

 void GCMAccountMapper::Initialize(const AccountMappings& account_mappings,
                                   const DispatchMessageCallback& callback) {
   DCHECK(!initialized_);
   initialized_ = true;
   accounts_ = account_mappings;
   dispatch_message_callback_ = callback;
   GetRegistration();
 }

 void GCMAccountMapper::SetAccountTokens(
     const std::vector<GCMClient::AccountTokenInfo>& account_tokens) {
   DVLOG(1) << "GCMAccountMapper::SetAccountTokens called with "
            << account_tokens.size() << " accounts.";

   // If account mapper is not ready to handle tasks yet, save the latest
   // account tokens and return.
   if (!IsReady()) {
     pending_account_tokens_ = account_tokens;
     // If mapper is initialized, but still does not have registration ID,
     // maybe the registration gave up. Retrying in case.
     if (initialized_ && gcm_driver_->IsStarted())
       GetRegistration();
     return;
   }

   // Start from removing the old tokens, from all of the known accounts.
   for (AccountMappings::iterator iter = accounts_.begin();
        iter != accounts_.end();
        ++iter) {
     iter->access_token.clear();
   }

   // Update the internal collection of mappings with the new tokens.
   for (std::vector<GCMClient::AccountTokenInfo>::const_iterator token_iter =
            account_tokens.begin();
        token_iter != account_tokens.end();
        ++token_iter) {
     AccountMapping* account_mapping =
         FindMappingByAccountId(token_iter->account_id);
     if (!account_mapping) {
       AccountMapping new_mapping;
       new_mapping.status = AccountMapping::NEW;
       new_mapping.account_id = token_iter->account_id;
       new_mapping.access_token = token_iter->access_token;
       new_mapping.email = token_iter->email;
       accounts_.push_back(new_mapping);
     } else {
       // Since we got a token for an account, drop the remove message and treat
       // it as mapped.
       if (account_mapping->status == AccountMapping::REMOVING) {
         account_mapping->status = AccountMapping::MAPPED;
         account_mapping->status_change_timestamp = base::Time();
         account_mapping->last_message_id.clear();
       }

       account_mapping->email = token_iter->email;
       account_mapping->access_token = token_iter->access_token;
     }
   }

   // Decide what to do with each account (either start mapping, or start
   // removing).
   for (AccountMappings::iterator mappings_iter = accounts_.begin();
        mappings_iter != accounts_.end();
        ++mappings_iter) {
     if (mappings_iter->access_token.empty()) {
       // Send a remove message if the account was not previously being removed,
       // or it doesn't have a pending message, or the pending message is
       // already expired, but OnSendError event was lost.
       if (mappings_iter->status != AccountMapping::REMOVING ||
           mappings_iter->last_message_id.empty() ||
           IsLastStatusChangeOlderThanTTL(*mappings_iter)) {
         SendRemoveMappingMessage(*mappings_iter);
       }
     } else {
       // A message is sent for all of the mappings considered NEW, or mappings
       // that are ADDING, but have expired message (OnSendError event lost), or
       // for those mapped accounts that can be refreshed.
       if (mappings_iter->status == AccountMapping::NEW ||
           (mappings_iter->status == AccountMapping::ADDING &&
            IsLastStatusChangeOlderThanTTL(*mappings_iter)) ||
           (mappings_iter->status == AccountMapping::MAPPED &&
            CanTriggerUpdate(mappings_iter->status_change_timestamp))) {
         mappings_iter->last_message_id.clear();
         SendAddMappingMessage(*mappings_iter);
       }
     }
   }
 }

 void GCMAccountMapper::ShutdownHandler() {
   initialized_ = false;
   accounts_.clear();
   registration_id_.clear();
   dispatch_message_callback_.Reset();
 }

 void GCMAccountMapper::OnStoreReset() {
   // TODO(crbug.com/661660): Tell server to remove the mapping. But can't use
   // upstream GCM send for that since the store got reset.
   ShutdownHandler();
 }

 void GCMAccountMapper::OnMessage(const std::string& app_id,
                                  const IncomingMessage& message) {
   DCHECK_EQ(app_id, kGCMAccountMapperAppId);
   // TODO(fgorski): Report Send to Gaia ID failures using UMA.

   if (dispatch_message_callback_.is_null()) {
     DVLOG(1) << "dispatch_message_callback_ missing in GCMAccountMapper";
     return;
   }

   MessageData::const_iterator it = message.data.find(kGCMSendToGaiaIdAppIdKey);
   if (it == message.data.end()) {
     DVLOG(1) << "Send to Gaia ID failure: Embedded app ID missing.";
     return;
   }

   std::string embedded_app_id = it->second;
   if (embedded_app_id.empty()) {
     DVLOG(1) << "Send to Gaia ID failure: Embedded app ID is empty.";
     return;
   }

   // Ensuring the message does not carry the embedded app ID.
   IncomingMessage new_message = message;
   new_message.data.erase(new_message.data.find(kGCMSendToGaiaIdAppIdKey));
   dispatch_message_callback_.Run(embedded_app_id, new_message);
 }

 void GCMAccountMapper::OnMessagesDeleted(const std::string& app_id) {
   // Account message does not expect messages right now.
 }

 void GCMAccountMapper::OnSendError(
     const std::string& app_id,
     const GCMClient::SendErrorDetails& send_error_details) {
   DCHECK_EQ(app_id, kGCMAccountMapperAppId);

   AccountMappings::iterator account_mapping_it =
       FindMappingByMessageId(send_error_details.message_id);

   if (account_mapping_it == accounts_.end())
     return;

   if (send_error_details.result != GCMClient::TTL_EXCEEDED) {
     DVLOG(1) << "Send error result different than TTL EXCEEDED: "
              << send_error_details.result << ". "
              << "Postponing the retry until a new batch of tokens arrives.";
     return;
   }

   if (account_mapping_it->status == AccountMapping::REMOVING) {
     // Another message to remove mapping can be sent immediately, because TTL
     // for those is one day. No need to back off.
     SendRemoveMappingMessage(*account_mapping_it);
   } else {
     if (account_mapping_it->status == AccountMapping::ADDING) {
       // There is no mapping established, so we can remove the entry.
       // Getting a fresh token will trigger a new attempt.
       gcm_driver_->RemoveAccountMapping(account_mapping_it->account_id);
       accounts_.erase(account_mapping_it);
     } else {
       // Account is already MAPPED, we have to wait for another token.
       account_mapping_it->last_message_id.clear();
       gcm_driver_->UpdateAccountMapping(*account_mapping_it);
     }
   }
 }

 void GCMAccountMapper::OnSendAcknowledged(const std::string& app_id,
                                           const std::string& message_id) {
   DCHECK_EQ(app_id, kGCMAccountMapperAppId);
   AccountMappings::iterator account_mapping_it =
       FindMappingByMessageId(message_id);

   DVLOG(1) << "OnSendAcknowledged with message ID: " << message_id;

   if (account_mapping_it == accounts_.end())
     return;

   // Here is where we advance a status of a mapping and persist or remove.
   if (account_mapping_it->status == AccountMapping::REMOVING) {
     // Message removing the account has been confirmed by the GCM, we can remove
     // all the information related to the account (from memory and store).
     gcm_driver_->RemoveAccountMapping(account_mapping_it->account_id);
     accounts_.erase(account_mapping_it);
   } else {
     // Mapping status is ADDING only when it is a first time mapping.
     DCHECK(account_mapping_it->status == AccountMapping::ADDING ||
            account_mapping_it->status == AccountMapping::MAPPED);

     // Account is marked as mapped with the current time.
     account_mapping_it->status = AccountMapping::MAPPED;
     account_mapping_it->status_change_timestamp = clock_->Now();
     // There is no pending message for the account.
     account_mapping_it->last_message_id.clear();

     gcm_driver_->UpdateAccountMapping(*account_mapping_it);
   }
 }

 bool GCMAccountMapper::CanHandle(const std::string& app_id) const {
   return app_id.compare(kGCMAccountMapperAppId) == 0;
 }

 bool GCMAccountMapper::IsReady() {
   return initialized_ && gcm_driver_->IsStarted() && !registration_id_.empty();
 }

 void GCMAccountMapper::SendAddMappingMessage(AccountMapping& account_mapping) {
   CreateAndSendMessage(account_mapping);
 }

 void GCMAccountMapper::SendRemoveMappingMessage(
     AccountMapping& account_mapping) {
   // We want to persist an account that is being removed as quickly as possible
   // as well as clean up the last message information.
   if (account_mapping.status != AccountMapping::REMOVING) {
     account_mapping.status = AccountMapping::REMOVING;
     account_mapping.status_change_timestamp = clock_->Now();
   }

   account_mapping.last_message_id.clear();

   gcm_driver_->UpdateAccountMapping(account_mapping);

   CreateAndSendMessage(account_mapping);
 }

 void GCMAccountMapper::CreateAndSendMessage(
     const AccountMapping& account_mapping) {
   OutgoingMessage outgoing_message;
   outgoing_message.id = GenerateMessageID();
   outgoing_message.data[kRegistrationIdMessgaeKey] = registration_id_;
   outgoing_message.data[kAccountMessageKey] = account_mapping.email;

   if (account_mapping.status == AccountMapping::REMOVING) {
     outgoing_message.time_to_live = kGCMRemoveMappingMessageTTL;
     outgoing_message.data[kRemoveAccountKey] = kRemoveAccountValue;
   } else {
     outgoing_message.data[kTokenMessageKey] = account_mapping.access_token;
     outgoing_message.time_to_live = kGCMAddMappingMessageTTL;
   }

   gcm_driver_->Send(kGCMAccountMapperAppId,
                     kGCMAccountMapperSendTo,
                     outgoing_message,
                     base::Bind(&GCMAccountMapper::OnSendFinished,
                                weak_ptr_factory_.GetWeakPtr(),
                                account_mapping.account_id));
 }

 void GCMAccountMapper::OnSendFinished(const std::string& account_id,
                                       const std::string& message_id,
                                       GCMClient::Result result) {
   // TODO(fgorski): Add another attempt, in case the QUEUE is not full.
   if (result != GCMClient::SUCCESS)
     return;

   AccountMapping* account_mapping = FindMappingByAccountId(account_id);
   DCHECK(account_mapping);

   // If we are dealing with account with status NEW, it is the first time
   // mapping, and we should mark it as ADDING.
   if (account_mapping->status == AccountMapping::NEW) {
     account_mapping->status = AccountMapping::ADDING;
     account_mapping->status_change_timestamp = clock_->Now();
   }

   account_mapping->last_message_id = message_id;

   gcm_driver_->UpdateAccountMapping(*account_mapping);
 }

 void GCMAccountMapper::GetRegistration() {
   DCHECK(registration_id_.empty());
   std::vector<std::string> sender_ids;
   sender_ids.push_back(kGCMAccountMapperSenderId);
   gcm_driver_->Register(kGCMAccountMapperAppId,
                         sender_ids,
                         base::Bind(&GCMAccountMapper::OnRegisterFinished,
                                    weak_ptr_factory_.GetWeakPtr()));
 }

 void GCMAccountMapper::OnRegisterFinished(const std::string& registration_id,
                                           GCMClient::Result result) {
   if (result == GCMClient::SUCCESS)
     registration_id_ = registration_id;

   if (IsReady()) {
     if (!pending_account_tokens_.empty()) {
       SetAccountTokens(pending_account_tokens_);
       pending_account_tokens_.clear();
     }
   }
 }

 bool GCMAccountMapper::CanTriggerUpdate(
     const base::Time& last_update_time) const {
   return last_update_time +
              base::TimeDelta::FromHours(kGCMUpdateIntervalHours -
                                         kGCMUpdateEarlyStartHours) <
          clock_->Now();
 }

 bool GCMAccountMapper::IsLastStatusChangeOlderThanTTL(
     const AccountMapping& account_mapping) const {
   int ttl_seconds = account_mapping.status == AccountMapping::REMOVING ?
       kGCMRemoveMappingMessageTTL : kGCMAddMappingMessageTTL;
   return account_mapping.status_change_timestamp +
       base::TimeDelta::FromSeconds(ttl_seconds) < clock_->Now();
 }

 AccountMapping* GCMAccountMapper::FindMappingByAccountId(
     const std::string& account_id) {
   for (AccountMappings::iterator iter = accounts_.begin();
        iter != accounts_.end();
        ++iter) {
     if (iter->account_id == account_id)
       return &*iter;
   }

   return nullptr;
 }

 GCMAccountMapper::AccountMappings::iterator
 GCMAccountMapper::FindMappingByMessageId(const std::string& message_id) {
   for (std::vector<AccountMapping>::iterator iter = accounts_.begin();
        iter != accounts_.end();
        ++iter) {
     if (iter->last_message_id == message_id)
       return iter;
   }

   return accounts_.end();
 }

 void GCMAccountMapper::SetClockForTesting(base::Clock* clock) {
   clock_ = clock;
 }

 }  // namespace gcm
	// Copyright 2014 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 "components/gcm_driver/gcm_account_mapper.h"

	#include <utility>

	#include "base/bind.h"
	#include "base/guid.h"
	#include "base/time/clock.h"
	#include "base/time/default_clock.h"
	#include "components/gcm_driver/gcm_driver_desktop.h"
	#include "google_apis/gcm/engine/gcm_store.h"

	namespace gcm {

	namespace {

	const char kGCMAccountMapperSenderId[] = "745476177629";
	const char kGCMAccountMapperSendTo[] = "google.com";
	const int kGCMAddMappingMessageTTL = 30 * 60; // 0.5 hours in seconds.
	const int kGCMRemoveMappingMessageTTL = 24 * 60 * 60; // 1 day in seconds.
	const int kGCMUpdateIntervalHours = 24;
	// Because adding an account mapping dependents on a fresh OAuth2 token, we
	// allow the update to happen earlier than update due time, if it is within
	// the early start time to take advantage of that token.
	const int kGCMUpdateEarlyStartHours = 6;
	const char kRegistrationIdMessgaeKey[] = "id";
	const char kTokenMessageKey[] = "t";
	const char kAccountMessageKey[] = "a";
	const char kRemoveAccountKey[] = "r";
	const char kRemoveAccountValue[] = "1";
	// Use to handle send to Gaia ID scenario:
	const char kGCMSendToGaiaIdAppIdKey[] = "gcmb";


	std::string GenerateMessageID() {
	return base::GenerateGUID();
	}

	} // namespace

	const char kGCMAccountMapperAppId[] = "com.google.android.gms";

	GCMAccountMapper::GCMAccountMapper(GCMDriver* gcm_driver)
	: gcm_driver_(gcm_driver),
	clock_(base::DefaultClock::GetInstance()),
	initialized_(false),
	weak_ptr_factory_(this) {}

	GCMAccountMapper::~GCMAccountMapper() {
	}

	void GCMAccountMapper::Initialize(const AccountMappings& account_mappings,
	const DispatchMessageCallback& callback) {
	DCHECK(!initialized_);
	initialized_ = true;
	accounts_ = account_mappings;
	dispatch_message_callback_ = callback;
	GetRegistration();
	}

	void GCMAccountMapper::SetAccountTokens(
	const std::vector<GCMClient::AccountTokenInfo>& account_tokens) {
	DVLOG(1) << "GCMAccountMapper::SetAccountTokens called with "
	<< account_tokens.size() << " accounts.";

	// If account mapper is not ready to handle tasks yet, save the latest
	// account tokens and return.
	if (!IsReady()) {
	pending_account_tokens_ = account_tokens;
	// If mapper is initialized, but still does not have registration ID,
	// maybe the registration gave up. Retrying in case.
	if (initialized_ && gcm_driver_->IsStarted())
	GetRegistration();
	return;
	}

	// Start from removing the old tokens, from all of the known accounts.
	for (AccountMappings::iterator iter = accounts_.begin();
	iter != accounts_.end();
	++iter) {
	iter->access_token.clear();
	}

	// Update the internal collection of mappings with the new tokens.
	for (std::vector<GCMClient::AccountTokenInfo>::const_iterator token_iter =
	account_tokens.begin();
	token_iter != account_tokens.end();
	++token_iter) {
	AccountMapping* account_mapping =
	FindMappingByAccountId(token_iter->account_id);
	if (!account_mapping) {
	AccountMapping new_mapping;
	new_mapping.status = AccountMapping::NEW;
	new_mapping.account_id = token_iter->account_id;
	new_mapping.access_token = token_iter->access_token;
	new_mapping.email = token_iter->email;
	accounts_.push_back(new_mapping);
	} else {
	// Since we got a token for an account, drop the remove message and treat
	// it as mapped.
	if (account_mapping->status == AccountMapping::REMOVING) {
	account_mapping->status = AccountMapping::MAPPED;
	account_mapping->status_change_timestamp = base::Time();
	account_mapping->last_message_id.clear();
	}

	account_mapping->email = token_iter->email;
	account_mapping->access_token = token_iter->access_token;
	}
	}

	// Decide what to do with each account (either start mapping, or start
	// removing).
	for (AccountMappings::iterator mappings_iter = accounts_.begin();
	mappings_iter != accounts_.end();
	++mappings_iter) {
	if (mappings_iter->access_token.empty()) {
	// Send a remove message if the account was not previously being removed,
	// or it doesn't have a pending message, or the pending message is
	// already expired, but OnSendError event was lost.
	if (mappings_iter->status != AccountMapping::REMOVING \|\|
	mappings_iter->last_message_id.empty() \|\|
	IsLastStatusChangeOlderThanTTL(*mappings_iter)) {
	SendRemoveMappingMessage(*mappings_iter);
	}
	} else {
	// A message is sent for all of the mappings considered NEW, or mappings
	// that are ADDING, but have expired message (OnSendError event lost), or
	// for those mapped accounts that can be refreshed.
	if (mappings_iter->status == AccountMapping::NEW \|\|
	(mappings_iter->status == AccountMapping::ADDING &&
	IsLastStatusChangeOlderThanTTL(*mappings_iter)) \|\|
	(mappings_iter->status == AccountMapping::MAPPED &&
	CanTriggerUpdate(mappings_iter->status_change_timestamp))) {
	mappings_iter->last_message_id.clear();
	SendAddMappingMessage(*mappings_iter);
	}
	}
	}
	}

	void GCMAccountMapper::ShutdownHandler() {
	initialized_ = false;
	accounts_.clear();
	registration_id_.clear();
	dispatch_message_callback_.Reset();
	}

	void GCMAccountMapper::OnStoreReset() {
	// TODO(crbug.com/661660): Tell server to remove the mapping. But can't use
	// upstream GCM send for that since the store got reset.
	ShutdownHandler();
	}

	void GCMAccountMapper::OnMessage(const std::string& app_id,
	const IncomingMessage& message) {
	DCHECK_EQ(app_id, kGCMAccountMapperAppId);
	// TODO(fgorski): Report Send to Gaia ID failures using UMA.

	if (dispatch_message_callback_.is_null()) {
	DVLOG(1) << "dispatch_message_callback_ missing in GCMAccountMapper";
	return;
	}

	MessageData::const_iterator it = message.data.find(kGCMSendToGaiaIdAppIdKey);
	if (it == message.data.end()) {
	DVLOG(1) << "Send to Gaia ID failure: Embedded app ID missing.";
	return;
	}

	std::string embedded_app_id = it->second;
	if (embedded_app_id.empty()) {
	DVLOG(1) << "Send to Gaia ID failure: Embedded app ID is empty.";
	return;
	}

	// Ensuring the message does not carry the embedded app ID.
	IncomingMessage new_message = message;
	new_message.data.erase(new_message.data.find(kGCMSendToGaiaIdAppIdKey));
	dispatch_message_callback_.Run(embedded_app_id, new_message);
	}

	void GCMAccountMapper::OnMessagesDeleted(const std::string& app_id) {
	// Account message does not expect messages right now.
	}

	void GCMAccountMapper::OnSendError(
	const std::string& app_id,
	const GCMClient::SendErrorDetails& send_error_details) {
	DCHECK_EQ(app_id, kGCMAccountMapperAppId);

	AccountMappings::iterator account_mapping_it =
	FindMappingByMessageId(send_error_details.message_id);

	if (account_mapping_it == accounts_.end())
	return;

	if (send_error_details.result != GCMClient::TTL_EXCEEDED) {
	DVLOG(1) << "Send error result different than TTL EXCEEDED: "
	<< send_error_details.result << ". "
	<< "Postponing the retry until a new batch of tokens arrives.";
	return;
	}

	if (account_mapping_it->status == AccountMapping::REMOVING) {
	// Another message to remove mapping can be sent immediately, because TTL
	// for those is one day. No need to back off.
	SendRemoveMappingMessage(*account_mapping_it);
	} else {
	if (account_mapping_it->status == AccountMapping::ADDING) {
	// There is no mapping established, so we can remove the entry.
	// Getting a fresh token will trigger a new attempt.
	gcm_driver_->RemoveAccountMapping(account_mapping_it->account_id);
	accounts_.erase(account_mapping_it);
	} else {
	// Account is already MAPPED, we have to wait for another token.
	account_mapping_it->last_message_id.clear();
	gcm_driver_->UpdateAccountMapping(*account_mapping_it);
	}
	}
	}

	void GCMAccountMapper::OnSendAcknowledged(const std::string& app_id,
	const std::string& message_id) {
	DCHECK_EQ(app_id, kGCMAccountMapperAppId);
	AccountMappings::iterator account_mapping_it =
	FindMappingByMessageId(message_id);

	DVLOG(1) << "OnSendAcknowledged with message ID: " << message_id;

	if (account_mapping_it == accounts_.end())
	return;

	// Here is where we advance a status of a mapping and persist or remove.
	if (account_mapping_it->status == AccountMapping::REMOVING) {
	// Message removing the account has been confirmed by the GCM, we can remove
	// all the information related to the account (from memory and store).
	gcm_driver_->RemoveAccountMapping(account_mapping_it->account_id);
	accounts_.erase(account_mapping_it);
	} else {
	// Mapping status is ADDING only when it is a first time mapping.
	DCHECK(account_mapping_it->status == AccountMapping::ADDING \|\|
	account_mapping_it->status == AccountMapping::MAPPED);

	// Account is marked as mapped with the current time.
	account_mapping_it->status = AccountMapping::MAPPED;
	account_mapping_it->status_change_timestamp = clock_->Now();
	// There is no pending message for the account.
	account_mapping_it->last_message_id.clear();

	gcm_driver_->UpdateAccountMapping(*account_mapping_it);
	}
	}

	bool GCMAccountMapper::CanHandle(const std::string& app_id) const {
	return app_id.compare(kGCMAccountMapperAppId) == 0;
	}

	bool GCMAccountMapper::IsReady() {
	return initialized_ && gcm_driver_->IsStarted() && !registration_id_.empty();
	}

	void GCMAccountMapper::SendAddMappingMessage(AccountMapping& account_mapping) {
	CreateAndSendMessage(account_mapping);
	}

	void GCMAccountMapper::SendRemoveMappingMessage(
	AccountMapping& account_mapping) {
	// We want to persist an account that is being removed as quickly as possible
	// as well as clean up the last message information.
	if (account_mapping.status != AccountMapping::REMOVING) {
	account_mapping.status = AccountMapping::REMOVING;
	account_mapping.status_change_timestamp = clock_->Now();
	}

	account_mapping.last_message_id.clear();

	gcm_driver_->UpdateAccountMapping(account_mapping);

	CreateAndSendMessage(account_mapping);
	}

	void GCMAccountMapper::CreateAndSendMessage(
	const AccountMapping& account_mapping) {
	OutgoingMessage outgoing_message;
	outgoing_message.id = GenerateMessageID();
	outgoing_message.data[kRegistrationIdMessgaeKey] = registration_id_;
	outgoing_message.data[kAccountMessageKey] = account_mapping.email;

	if (account_mapping.status == AccountMapping::REMOVING) {
	outgoing_message.time_to_live = kGCMRemoveMappingMessageTTL;
	outgoing_message.data[kRemoveAccountKey] = kRemoveAccountValue;
	} else {
	outgoing_message.data[kTokenMessageKey] = account_mapping.access_token;
	outgoing_message.time_to_live = kGCMAddMappingMessageTTL;
	}

	gcm_driver_->Send(kGCMAccountMapperAppId,
	kGCMAccountMapperSendTo,
	outgoing_message,
	base::Bind(&GCMAccountMapper::OnSendFinished,
	weak_ptr_factory_.GetWeakPtr(),
	account_mapping.account_id));
	}

	void GCMAccountMapper::OnSendFinished(const std::string& account_id,
	const std::string& message_id,
	GCMClient::Result result) {
	// TODO(fgorski): Add another attempt, in case the QUEUE is not full.
	if (result != GCMClient::SUCCESS)
	return;

	AccountMapping* account_mapping = FindMappingByAccountId(account_id);
	DCHECK(account_mapping);

	// If we are dealing with account with status NEW, it is the first time
	// mapping, and we should mark it as ADDING.
	if (account_mapping->status == AccountMapping::NEW) {
	account_mapping->status = AccountMapping::ADDING;
	account_mapping->status_change_timestamp = clock_->Now();
	}

	account_mapping->last_message_id = message_id;

	gcm_driver_->UpdateAccountMapping(*account_mapping);
	}

	void GCMAccountMapper::GetRegistration() {
	DCHECK(registration_id_.empty());
	std::vector<std::string> sender_ids;
	sender_ids.push_back(kGCMAccountMapperSenderId);
	gcm_driver_->Register(kGCMAccountMapperAppId,
	sender_ids,
	base::Bind(&GCMAccountMapper::OnRegisterFinished,
	weak_ptr_factory_.GetWeakPtr()));
	}

	void GCMAccountMapper::OnRegisterFinished(const std::string& registration_id,
	GCMClient::Result result) {
	if (result == GCMClient::SUCCESS)
	registration_id_ = registration_id;

	if (IsReady()) {
	if (!pending_account_tokens_.empty()) {
	SetAccountTokens(pending_account_tokens_);
	pending_account_tokens_.clear();
	}
	}
	}

	bool GCMAccountMapper::CanTriggerUpdate(
	const base::Time& last_update_time) const {
	return last_update_time +
	base::TimeDelta::FromHours(kGCMUpdateIntervalHours -
	kGCMUpdateEarlyStartHours) <
	clock_->Now();
	}

	bool GCMAccountMapper::IsLastStatusChangeOlderThanTTL(
	const AccountMapping& account_mapping) const {
	int ttl_seconds = account_mapping.status == AccountMapping::REMOVING ?
	kGCMRemoveMappingMessageTTL : kGCMAddMappingMessageTTL;
	return account_mapping.status_change_timestamp +
	base::TimeDelta::FromSeconds(ttl_seconds) < clock_->Now();
	}

	AccountMapping* GCMAccountMapper::FindMappingByAccountId(
	const std::string& account_id) {
	for (AccountMappings::iterator iter = accounts_.begin();
	iter != accounts_.end();
	++iter) {
	if (iter->account_id == account_id)
	return &*iter;
	}

	return nullptr;
	}

	GCMAccountMapper::AccountMappings::iterator
	GCMAccountMapper::FindMappingByMessageId(const std::string& message_id) {
	for (std::vector<AccountMapping>::iterator iter = accounts_.begin();
	iter != accounts_.end();
	++iter) {
	if (iter->last_message_id == message_id)
	return iter;
	}

	return accounts_.end();
	}

	void GCMAccountMapper::SetClockForTesting(base::Clock* clock) {
	clock_ = clock;
	}

	} // namespace gcm