Refactor: Extract "InitProxyResolver" to "ProxyScriptDecider".

net/proxy/init_proxy_resolver.cc

Index: net/proxy/init_proxy_resolver.cc
===================================================================
--- net/proxy/init_proxy_resolver.cc	(revision 114271)
+++ net/proxy/init_proxy_resolver.cc	(working copy)
@@ -1,382 +0,0 @@
-// Copyright (c) 2011 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 "net/proxy/init_proxy_resolver.h"
-
-#include "base/compiler_specific.h"
-#include "base/format_macros.h"
-#include "base/logging.h"
-#include "base/string_util.h"
-#include "net/base/net_log.h"
-#include "net/base/net_errors.h"
-#include "net/proxy/dhcp_proxy_script_fetcher.h"
-#include "net/proxy/dhcp_proxy_script_fetcher_factory.h"
-#include "net/proxy/proxy_config.h"
-#include "net/proxy/proxy_resolver.h"
-#include "net/proxy/proxy_script_fetcher.h"
-
-namespace net {
-
-// This is the hard-coded location used by the DNS portion of web proxy
-// auto-discovery.
-//
-// Note that we not use DNS devolution to find the WPAD host, since that could
-// be dangerous should our top level domain registry  become out of date.
-//
-// Instead we directly resolve "wpad", and let the operating system apply the
-// DNS suffix search paths. This is the same approach taken by Firefox, and
-// compatibility hasn't been an issue.
-//
-// For more details, also check out this comment:
-// http://code.google.com/p/chromium/issues/detail?id=18575#c20
-static const char kWpadUrl[] = "http://wpad/wpad.dat";
-
-InitProxyResolver::InitProxyResolver(
-    ProxyResolver* resolver,
-    ProxyScriptFetcher* proxy_script_fetcher,
-    DhcpProxyScriptFetcher* dhcp_proxy_script_fetcher,
-    NetLog* net_log)
-    : resolver_(resolver),
-      proxy_script_fetcher_(proxy_script_fetcher),
-      dhcp_proxy_script_fetcher_(dhcp_proxy_script_fetcher),
-      ALLOW_THIS_IN_INITIALIZER_LIST(io_callback_(
-          this, &InitProxyResolver::OnIOCompletion)),
-      user_callback_(NULL),
-      current_pac_source_index_(0u),
-      pac_mandatory_(false),
-      next_state_(STATE_NONE),
-      net_log_(BoundNetLog::Make(
-          net_log, NetLog::SOURCE_INIT_PROXY_RESOLVER)),
-      effective_config_(NULL) {
-}
-
-InitProxyResolver::~InitProxyResolver() {
-  if (next_state_ != STATE_NONE)
-    Cancel();
-}
-
-int InitProxyResolver::Init(const ProxyConfig& config,
-                            const base::TimeDelta wait_delay,
-                            ProxyConfig* effective_config,
-                            OldCompletionCallback* callback) {
-  DCHECK_EQ(STATE_NONE, next_state_);
-  DCHECK(callback);
-  DCHECK(config.HasAutomaticSettings());
-
-  net_log_.BeginEvent(NetLog::TYPE_INIT_PROXY_RESOLVER, NULL);
-
-  // Save the |wait_delay| as a non-negative value.
-  wait_delay_ = wait_delay;
-  if (wait_delay_ < base::TimeDelta())
-    wait_delay_ = base::TimeDelta();
-
-  effective_config_ = effective_config;
-
-  pac_mandatory_ = config.pac_mandatory();
-
-  pac_sources_ = BuildPacSourcesFallbackList(config);
-  DCHECK(!pac_sources_.empty());
-
-  next_state_ = STATE_WAIT;
-
-  int rv = DoLoop(OK);
-  if (rv == ERR_IO_PENDING)
-    user_callback_ = callback;
-  else
-    DidCompleteInit();
-
-  return rv;
-}
-
-// Initialize the fallback rules.
-// (1) WPAD (DHCP).
-// (2) WPAD (DNS).
-// (3) Custom PAC URL.
-InitProxyResolver::PacSourceList InitProxyResolver::BuildPacSourcesFallbackList(
-    const ProxyConfig& config) const {
-  PacSourceList pac_sources;
-  if (config.auto_detect()) {
-    pac_sources.push_back(PacSource(PacSource::WPAD_DHCP, GURL()));
-    pac_sources.push_back(PacSource(PacSource::WPAD_DNS, GURL()));
-  }
-  if (config.has_pac_url())
-    pac_sources.push_back(PacSource(PacSource::CUSTOM, config.pac_url()));
-  return pac_sources;
-}
-
-void InitProxyResolver::OnIOCompletion(int result) {
-  DCHECK_NE(STATE_NONE, next_state_);
-  int rv = DoLoop(result);
-  if (rv != ERR_IO_PENDING) {
-    DidCompleteInit();
-    DoCallback(rv);
-  }
-}
-
-int InitProxyResolver::DoLoop(int result) {
-  DCHECK_NE(next_state_, STATE_NONE);
-  int rv = result;
-  do {
-    State state = next_state_;
-    next_state_ = STATE_NONE;
-    switch (state) {
-      case STATE_WAIT:
-        DCHECK_EQ(OK, rv);
-        rv = DoWait();
-        break;
-      case STATE_WAIT_COMPLETE:
-        rv = DoWaitComplete(rv);
-        break;
-      case STATE_FETCH_PAC_SCRIPT:
-        DCHECK_EQ(OK, rv);
-        rv = DoFetchPacScript();
-        break;
-      case STATE_FETCH_PAC_SCRIPT_COMPLETE:
-        rv = DoFetchPacScriptComplete(rv);
-        break;
-      case STATE_SET_PAC_SCRIPT:
-        DCHECK_EQ(OK, rv);
-        rv = DoSetPacScript();
-        break;
-      case STATE_SET_PAC_SCRIPT_COMPLETE:
-        rv = DoSetPacScriptComplete(rv);
-        break;
-      default:
-        NOTREACHED() << "bad state";
-        rv = ERR_UNEXPECTED;
-        break;
-    }
-  } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
-  return rv;
-}
-
-void InitProxyResolver::DoCallback(int result) {
-  DCHECK_NE(ERR_IO_PENDING, result);
-  DCHECK(user_callback_);
-  user_callback_->Run(result);
-}
-
-int InitProxyResolver::DoWait() {
-  next_state_ = STATE_WAIT_COMPLETE;
-
-  // If no waiting is required, continue on to the next state.
-  if (wait_delay_.ToInternalValue() == 0)
-    return OK;
-
-  // Otherwise wait the specified amount of time.
-  wait_timer_.Start(FROM_HERE, wait_delay_, this,
-                    &InitProxyResolver::OnWaitTimerFired);
-  net_log_.BeginEvent(NetLog::TYPE_INIT_PROXY_RESOLVER_WAIT, NULL);
-  return ERR_IO_PENDING;
-}
-
-int InitProxyResolver::DoWaitComplete(int result) {
-  DCHECK_EQ(OK, result);
-  if (wait_delay_.ToInternalValue() != 0) {
-    net_log_.EndEventWithNetErrorCode(NetLog::TYPE_INIT_PROXY_RESOLVER_WAIT,
-                                      result);
-  }
-  next_state_ = GetStartState();
-  return OK;
-}
-
-int InitProxyResolver::DoFetchPacScript() {
-  DCHECK(resolver_->expects_pac_bytes());
-
-  next_state_ = STATE_FETCH_PAC_SCRIPT_COMPLETE;
-
-  const PacSource& pac_source = current_pac_source();
-
-  GURL effective_pac_url;
-  NetLogStringParameter* log_parameter =
-      CreateNetLogParameterAndDetermineURL(pac_source, &effective_pac_url);
-
-  net_log_.BeginEvent(
-      NetLog::TYPE_INIT_PROXY_RESOLVER_FETCH_PAC_SCRIPT,
-      make_scoped_refptr(log_parameter));
-
-  if (pac_source.type == PacSource::WPAD_DHCP) {
-    if (!dhcp_proxy_script_fetcher_) {
-      net_log_.AddEvent(NetLog::TYPE_INIT_PROXY_RESOLVER_HAS_NO_FETCHER, NULL);
-      return ERR_UNEXPECTED;
-    }
-
-    return dhcp_proxy_script_fetcher_->Fetch(&pac_script_, &io_callback_);
-  }
-
-  if (!proxy_script_fetcher_) {
-    net_log_.AddEvent(NetLog::TYPE_INIT_PROXY_RESOLVER_HAS_NO_FETCHER, NULL);
-    return ERR_UNEXPECTED;
-  }
-
-  return proxy_script_fetcher_->Fetch(
-      effective_pac_url, &pac_script_, &io_callback_);
-}
-
-int InitProxyResolver::DoFetchPacScriptComplete(int result) {
-  DCHECK(resolver_->expects_pac_bytes());
-
-  net_log_.EndEventWithNetErrorCode(
-      NetLog::TYPE_INIT_PROXY_RESOLVER_FETCH_PAC_SCRIPT, result);
-  if (result != OK)
-    return TryToFallbackPacSource(result);
-
-  next_state_ = STATE_SET_PAC_SCRIPT;
-  return result;
-}
-
-int InitProxyResolver::DoSetPacScript() {
-  net_log_.BeginEvent(NetLog::TYPE_INIT_PROXY_RESOLVER_SET_PAC_SCRIPT, NULL);
-
-  const PacSource& pac_source = current_pac_source();
-
-  next_state_ = STATE_SET_PAC_SCRIPT_COMPLETE;
-
-  scoped_refptr<ProxyResolverScriptData> script_data;
-
-  if (resolver_->expects_pac_bytes()) {
-    script_data = ProxyResolverScriptData::FromUTF16(pac_script_);
-  } else {
-    script_data = pac_source.type == PacSource::CUSTOM ?
-        ProxyResolverScriptData::FromURL(pac_source.url) :
-        ProxyResolverScriptData::ForAutoDetect();
-  }
-
-  return resolver_->SetPacScript(script_data, &io_callback_);
-}
-
-int InitProxyResolver::DoSetPacScriptComplete(int result) {
-  net_log_.EndEventWithNetErrorCode(
-      NetLog::TYPE_INIT_PROXY_RESOLVER_SET_PAC_SCRIPT, result);
-  if (result != OK)
-    return TryToFallbackPacSource(result);
-
-  // Let the caller know which automatic setting we ended up initializing the
-  // resolver for (there may have been multiple fallbacks to choose from.)
-  if (effective_config_) {
-    if (current_pac_source().type == PacSource::CUSTOM) {
-      *effective_config_ =
-          ProxyConfig::CreateFromCustomPacURL(current_pac_source().url);
-      effective_config_->set_pac_mandatory(pac_mandatory_);
-    } else {
-      if (resolver_->expects_pac_bytes()) {
-        GURL auto_detected_url;
-
-        switch (current_pac_source().type) {
-          case PacSource::WPAD_DHCP:
-            auto_detected_url = dhcp_proxy_script_fetcher_->GetPacURL();
-            break;
-
-          case PacSource::WPAD_DNS:
-            auto_detected_url = GURL(kWpadUrl);
-            break;
-
-          default:
-            NOTREACHED();
-        }
-
-        *effective_config_ =
-            ProxyConfig::CreateFromCustomPacURL(auto_detected_url);
-      } else {
-        // The resolver does its own resolution so we cannot know the
-        // URL. Just do the best we can and state that the configuration
-        // is to auto-detect proxy settings.
-        *effective_config_ = ProxyConfig::CreateAutoDetect();
-      }
-    }
-  }
-
-  return result;
-}
-
-int InitProxyResolver::TryToFallbackPacSource(int error) {
-  DCHECK_LT(error, 0);
-
-  if (current_pac_source_index_ + 1 >= pac_sources_.size()) {
-    // Nothing left to fall back to.
-    return error;
-  }
-
-  // Advance to next URL in our list.
-  ++current_pac_source_index_;
-
-  net_log_.AddEvent(
-      NetLog::TYPE_INIT_PROXY_RESOLVER_FALLING_BACK_TO_NEXT_PAC_SOURCE, NULL);
-
-  next_state_ = GetStartState();
-
-  return OK;
-}
-
-InitProxyResolver::State InitProxyResolver::GetStartState() const {
-  return resolver_->expects_pac_bytes() ?
-      STATE_FETCH_PAC_SCRIPT : STATE_SET_PAC_SCRIPT;
-}
-
-NetLogStringParameter* InitProxyResolver::CreateNetLogParameterAndDetermineURL(
-    const PacSource& pac_source,
-    GURL* effective_pac_url) {
-  DCHECK(effective_pac_url);
-
-  std::string source_field;
-  switch (pac_source.type) {
-    case PacSource::WPAD_DHCP:
-      source_field = "WPAD DHCP";
-      break;
-    case PacSource::WPAD_DNS:
-      *effective_pac_url = GURL(kWpadUrl);
-      source_field = "WPAD DNS: ";
-      source_field += effective_pac_url->possibly_invalid_spec();
-      break;
-    case PacSource::CUSTOM:
-      *effective_pac_url = pac_source.url;
-      source_field = "Custom PAC URL: ";
-      source_field += effective_pac_url->possibly_invalid_spec();
-      break;
-  }
-  return new NetLogStringParameter("source", source_field);
-}
-
-const InitProxyResolver::PacSource&
-    InitProxyResolver::current_pac_source() const {
-  DCHECK_LT(current_pac_source_index_, pac_sources_.size());
-  return pac_sources_[current_pac_source_index_];
-}
-
-void InitProxyResolver::OnWaitTimerFired() {
-  OnIOCompletion(OK);
-}
-
-void InitProxyResolver::DidCompleteInit() {
-  net_log_.EndEvent(NetLog::TYPE_INIT_PROXY_RESOLVER, NULL);
-}
-
-void InitProxyResolver::Cancel() {
-  DCHECK_NE(STATE_NONE, next_state_);
-
-  net_log_.AddEvent(NetLog::TYPE_CANCELLED, NULL);
-
-  switch (next_state_) {
-    case STATE_WAIT_COMPLETE:
-      wait_timer_.Stop();
-      break;
-    case STATE_FETCH_PAC_SCRIPT_COMPLETE:
-      proxy_script_fetcher_->Cancel();
-      break;
-    case STATE_SET_PAC_SCRIPT_COMPLETE:
-      resolver_->CancelSetPacScript();
-      break;
-    default:
-      NOTREACHED();
-      break;
-  }
-
-  // This is safe to call in any state.
-  if (dhcp_proxy_script_fetcher_)
-    dhcp_proxy_script_fetcher_->Cancel();
-
-  DidCompleteInit();
-}
-
-}  // namespace net