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// Copyright (c) 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 "google_apis/gcm/engine/connection_factory_impl.h"
#include "base/message_loop/message_loop.h"
#include "google_apis/gcm/engine/connection_handler_impl.h"
#include "google_apis/gcm/protocol/mcs.pb.h"
#include "net/base/net_errors.h"
#include "net/http/http_network_session.h"
#include "net/http/http_request_headers.h"
#include "net/proxy/proxy_info.h"
#include "net/socket/client_socket_handle.h"
#include "net/socket/client_socket_pool_manager.h"
#include "net/ssl/ssl_config_service.h"
namespace gcm {
namespace {
// The amount of time a Socket read should wait before timing out.
const int kReadTimeoutMs = 30000; // 30 seconds.
// Backoff policy.
const net::BackoffEntry::Policy kConnectionBackoffPolicy = {
// Number of initial errors (in sequence) to ignore before applying
// exponential back-off rules.
0,
// Initial delay for exponential back-off in ms.
10000, // 10 seconds.
// Factor by which the waiting time will be multiplied.
2,
// Fuzzing percentage. ex: 10% will spread requests randomly
// between 90%-100% of the calculated time.
0.2, // 20%.
// Maximum amount of time we are willing to delay our request in ms.
1000 * 3600 * 4, // 4 hours.
// Time to keep an entry from being discarded even when it
// has no significant state, -1 to never discard.
-1,
// Don't use initial delay unless the last request was an error.
false,
};
} // namespace
ConnectionFactoryImpl::ConnectionFactoryImpl(
const GURL& mcs_endpoint,
scoped_refptr<net::HttpNetworkSession> network_session,
net::NetLog* net_log)
: mcs_endpoint_(mcs_endpoint),
network_session_(network_session),
net_log_(net_log),
weak_ptr_factory_(this) {
}
ConnectionFactoryImpl::~ConnectionFactoryImpl() {
}
void ConnectionFactoryImpl::Initialize(
const BuildLoginRequestCallback& request_builder,
const ConnectionHandler::ProtoReceivedCallback& read_callback,
const ConnectionHandler::ProtoSentCallback& write_callback) {
DCHECK(!connection_handler_);
backoff_entry_ = CreateBackoffEntry(&kConnectionBackoffPolicy);
request_builder_ = request_builder;
net::NetworkChangeNotifier::AddIPAddressObserver(this);
net::NetworkChangeNotifier::AddConnectionTypeObserver(this);
connection_handler_.reset(
new ConnectionHandlerImpl(
base::TimeDelta::FromMilliseconds(kReadTimeoutMs),
read_callback,
write_callback,
base::Bind(&ConnectionFactoryImpl::ConnectionHandlerCallback,
weak_ptr_factory_.GetWeakPtr())));
}
ConnectionHandler* ConnectionFactoryImpl::GetConnectionHandler() const {
return connection_handler_.get();
}
void ConnectionFactoryImpl::Connect() {
DCHECK(connection_handler_);
DCHECK(!IsEndpointReachable());
if (backoff_entry_->ShouldRejectRequest()) {
DVLOG(1) << "Delaying MCS endpoint connection for "
<< backoff_entry_->GetTimeUntilRelease().InMilliseconds()
<< " milliseconds.";
base::MessageLoop::current()->PostDelayedTask(
FROM_HERE,
base::Bind(&ConnectionFactoryImpl::Connect,
weak_ptr_factory_.GetWeakPtr()),
NextRetryAttempt() - base::TimeTicks::Now());
return;
}
DVLOG(1) << "Attempting connection to MCS endpoint.";
ConnectImpl();
}
bool ConnectionFactoryImpl::IsEndpointReachable() const {
return connection_handler_ && connection_handler_->CanSendMessage();
}
base::TimeTicks ConnectionFactoryImpl::NextRetryAttempt() const {
if (!backoff_entry_)
return base::TimeTicks();
return backoff_entry_->GetReleaseTime();
}
void ConnectionFactoryImpl::OnConnectionTypeChanged(
net::NetworkChangeNotifier::ConnectionType type) {
if (type == net::NetworkChangeNotifier::CONNECTION_NONE)
return;
// TODO(zea): implement different backoff/retry policies based on connection
// type.
DVLOG(1) << "Connection type changed to " << type << ", resetting backoff.";
backoff_entry_->Reset();
// Connect(..) should be retrying with backoff already if a connection is
// necessary, so no need to call again.
}
void ConnectionFactoryImpl::OnIPAddressChanged() {
DVLOG(1) << "IP Address changed, resetting backoff.";
backoff_entry_->Reset();
// Connect(..) should be retrying with backoff already if a connection is
// necessary, so no need to call again.
}
void ConnectionFactoryImpl::ConnectImpl() {
DCHECK(!IsEndpointReachable());
// TODO(zea): resolve proxies.
net::ProxyInfo proxy_info;
proxy_info.UseDirect();
net::SSLConfig ssl_config;
network_session_->ssl_config_service()->GetSSLConfig(&ssl_config);
int status = net::InitSocketHandleForTlsConnect(
net::HostPortPair::FromURL(mcs_endpoint_),
network_session_.get(),
proxy_info,
ssl_config,
ssl_config,
net::kPrivacyModeDisabled,
net::BoundNetLog::Make(net_log_, net::NetLog::SOURCE_SOCKET),
&socket_handle_,
base::Bind(&ConnectionFactoryImpl::OnConnectDone,
weak_ptr_factory_.GetWeakPtr()));
if (status != net::ERR_IO_PENDING)
OnConnectDone(status);
}
void ConnectionFactoryImpl::InitHandler() {
// May be null in tests.
mcs_proto::LoginRequest login_request;
if (!request_builder_.is_null()) {
request_builder_.Run(&login_request);
DCHECK(login_request.IsInitialized());
}
connection_handler_->Init(login_request, socket_handle_.PassSocket());
}
scoped_ptr<net::BackoffEntry> ConnectionFactoryImpl::CreateBackoffEntry(
const net::BackoffEntry::Policy* const policy) {
return scoped_ptr<net::BackoffEntry>(new net::BackoffEntry(policy));
}
void ConnectionFactoryImpl::OnConnectDone(int result) {
if (result != net::OK) {
LOG(ERROR) << "Failed to connect to MCS endpoint with error " << result;
backoff_entry_->InformOfRequest(false);
Connect();
return;
}
DVLOG(1) << "MCS endpoint connection success.";
// Reset the backoff.
backoff_entry_->Reset();
InitHandler();
}
void ConnectionFactoryImpl::ConnectionHandlerCallback(int result) {
// TODO(zea): Consider how to handle errors that may require some sort of
// user intervention (login page, etc.).
LOG(ERROR) << "Connection reset with error " << result;
backoff_entry_->InformOfRequest(false);
Connect();
}
} // namespace gcm
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