components/plugins/renderer/loadable_plugin_placeholder.cc

   1 // Copyright 2015 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 #include "components/plugins/renderer/loadable_plugin_placeholder.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/command_line.h"
  10 #include "base/json/string_escape.h"
  11 #include "base/strings/string_piece.h"
  12 #include "base/strings/utf_string_conversions.h"
  13 #include "base/values.h"
  14 #include "content/public/child/v8_value_converter.h"
  15 #include "content/public/common/content_switches.h"
  16 #include "content/public/renderer/render_frame.h"
  17 #include "content/public/renderer/render_thread.h"
  18 #include "gin/handle.h"
  19 #include "gin/object_template_builder.h"
  20 #include "third_party/WebKit/public/web/WebDOMMessageEvent.h"
  21 #include "third_party/WebKit/public/web/WebDocument.h"
  22 #include "third_party/WebKit/public/web/WebElement.h"
  23 #include "third_party/WebKit/public/web/WebInputEvent.h"
  24 #include "third_party/WebKit/public/web/WebKit.h"
  25 #include "third_party/WebKit/public/web/WebLocalFrame.h"
  26 #include "third_party/WebKit/public/web/WebPluginContainer.h"
  27 #include "third_party/WebKit/public/web/WebScriptSource.h"
  28 #include "third_party/WebKit/public/web/WebSerializedScriptValue.h"
  29 #include "third_party/WebKit/public/web/WebView.h"
  30
  31 using base::UserMetricsAction;
  32 using content::PluginInstanceThrottler;
  33 using content::RenderThread;
  34
  35 namespace plugins {
  36
  37 void LoadablePluginPlaceholder::BlockForPowerSaverPoster() {
  38   DCHECK(!is_blocked_for_power_saver_poster_);
  39   is_blocked_for_power_saver_poster_ = true;
  40
  41   render_frame()->RegisterPeripheralPlugin(
  42       GURL(GetPluginParams().url).GetOrigin(),
  43       base::Bind(&LoadablePluginPlaceholder::MarkPluginEssential,
  44                  weak_factory_.GetWeakPtr(),
  45                  PluginInstanceThrottler::UNTHROTTLE_METHOD_BY_WHITELIST));
  46 }
  47
  48 void LoadablePluginPlaceholder::SetPremadePlugin(
  49     content::PluginInstanceThrottler* throttler) {
  50   DCHECK(throttler);
  51   DCHECK(!premade_throttler_);
  52   premade_throttler_ = throttler;
  53 }
  54
  55 LoadablePluginPlaceholder::LoadablePluginPlaceholder(
  56     content::RenderFrame* render_frame,
  57     blink::WebLocalFrame* frame,
  58     const blink::WebPluginParams& params,
  59     const std::string& html_data)
  60     : PluginPlaceholder(render_frame, frame, params, html_data),
  61       is_blocked_for_background_tab_(false),
  62       is_blocked_for_prerendering_(false),
  63       is_blocked_for_power_saver_poster_(false),
  64       power_saver_enabled_(false),
  65       premade_throttler_(nullptr),
  66       allow_loading_(true),
  67       finished_loading_(false),
  68       weak_factory_(this) {
  69 }
  70
  71 LoadablePluginPlaceholder::~LoadablePluginPlaceholder() {
  72 }
  73
  74 void LoadablePluginPlaceholder::MarkPluginEssential(
  75     PluginInstanceThrottler::PowerSaverUnthrottleMethod method) {
  76   if (!power_saver_enabled_)
  77     return;
  78
  79   power_saver_enabled_ = false;
  80
  81   if (premade_throttler_)
  82     premade_throttler_->MarkPluginEssential(method);
  83   else
  84     PluginInstanceThrottler::RecordUnthrottleMethodMetric(method);
  85
  86   if (is_blocked_for_power_saver_poster_) {
  87     is_blocked_for_power_saver_poster_ = false;
  88     if (!LoadingBlocked())
  89       LoadPlugin();
  90   }
  91 }
  92
  93 gin::ObjectTemplateBuilder LoadablePluginPlaceholder::GetObjectTemplateBuilder(
  94     v8::Isolate* isolate) {
  95   return PluginPlaceholder::GetObjectTemplateBuilder(isolate)
  96       .SetMethod("load", &LoadablePluginPlaceholder::LoadCallback)
  97       .SetMethod("didFinishLoading",
  98                  &LoadablePluginPlaceholder::DidFinishLoadingCallback);
  99 }
 100
 101 void LoadablePluginPlaceholder::ReplacePlugin(blink::WebPlugin* new_plugin) {
 102   CHECK(plugin());
 103   if (!new_plugin)
 104     return;
 105   blink::WebPluginContainer* container = plugin()->container();
 106   // Set the new plugin on the container before initializing it.
 107   container->setPlugin(new_plugin);
 108   // Save the element in case the plugin is removed from the page during
 109   // initialization.
 110   blink::WebElement element = container->element();
 111   bool plugin_needs_initialization =
 112       !premade_throttler_ || new_plugin != premade_throttler_->GetWebPlugin();
 113   if (plugin_needs_initialization && !new_plugin->initialize(container)) {
 114     // We couldn't initialize the new plugin. Restore the old one and abort.
 115     container->setPlugin(plugin());
 116     return;
 117   }
 118
 119   // The plugin has been removed from the page. Destroy the old plugin. We
 120   // will be destroyed as soon as V8 garbage collects us.
 121   if (!element.pluginContainer()) {
 122     plugin()->destroy();
 123     return;
 124   }
 125
 126   // During initialization, the new plugin might have replaced itself in turn
 127   // with another plugin. Make sure not to use the passed in |new_plugin| after
 128   // this point.
 129   new_plugin = container->plugin();
 130
 131   plugin()->RestoreTitleText();
 132   container->invalidate();
 133   container->reportGeometry();
 134   plugin()->ReplayReceivedData(new_plugin);
 135   plugin()->destroy();
 136 }
 137
 138 void LoadablePluginPlaceholder::SetMessage(const base::string16& message) {
 139   message_ = message;
 140   if (finished_loading_)
 141     UpdateMessage();
 142 }
 143
 144 void LoadablePluginPlaceholder::UpdateMessage() {
 145   if (!plugin())
 146     return;
 147   std::string script =
 148       "window.setMessage(" + base::GetQuotedJSONString(message_) + ")";
 149   plugin()->web_view()->mainFrame()->executeScript(
 150       blink::WebScriptSource(base::UTF8ToUTF16(script)));
 151 }
 152
 153 void LoadablePluginPlaceholder::PluginDestroyed() {
 154   if (power_saver_enabled_) {
 155     if (premade_throttler_) {
 156       // Since the premade plugin has been detached from the container, it will
 157       // not be automatically destroyed along with the page.
 158       premade_throttler_->GetWebPlugin()->destroy();
 159       premade_throttler_ = nullptr;
 160     } else if (is_blocked_for_power_saver_poster_) {
 161       // Record the NEVER unthrottle count only if there is no throttler.
 162       PluginInstanceThrottler::RecordUnthrottleMethodMetric(
 163           PluginInstanceThrottler::UNTHROTTLE_METHOD_NEVER);
 164     }
 165
 166     // Prevent processing subsequent calls to MarkPluginEssential.
 167     power_saver_enabled_ = false;
 168   }
 169
 170   PluginPlaceholder::PluginDestroyed();
 171 }
 172
 173 v8::Local<v8::Object> LoadablePluginPlaceholder::GetV8ScriptableObject(
 174     v8::Isolate* isolate) const {
 175   // Pass through JavaScript access to the underlying throttled plugin.
 176   if (premade_throttler_ && premade_throttler_->GetWebPlugin()) {
 177     return premade_throttler_->GetWebPlugin()->v8ScriptableObject(isolate);
 178   }
 179   return v8::Local<v8::Object>();
 180 }
 181
 182 void LoadablePluginPlaceholder::WasShown() {
 183   if (is_blocked_for_background_tab_) {
 184     is_blocked_for_background_tab_ = false;
 185     if (!LoadingBlocked())
 186       LoadPlugin();
 187   }
 188 }
 189
 190 void LoadablePluginPlaceholder::OnLoadBlockedPlugins(
 191     const std::string& identifier) {
 192   if (!identifier.empty() && identifier != identifier_)
 193     return;
 194
 195   RenderThread::Get()->RecordAction(UserMetricsAction("Plugin_Load_UI"));
 196   LoadPlugin();
 197 }
 198
 199 void LoadablePluginPlaceholder::OnSetIsPrerendering(bool is_prerendering) {
 200   // Prerendering can only be enabled prior to a RenderView's first navigation,
 201   // so no BlockedPlugin should see the notification that enables prerendering.
 202   DCHECK(!is_prerendering);
 203   if (is_blocked_for_prerendering_) {
 204     is_blocked_for_prerendering_ = false;
 205     if (!LoadingBlocked())
 206       LoadPlugin();
 207   }
 208 }
 209
 210 void LoadablePluginPlaceholder::LoadPlugin() {
 211   // This is not strictly necessary but is an important defense in case the
 212   // event propagation changes between "close" vs. "click-to-play".
 213   if (hidden())
 214     return;
 215   if (!plugin())
 216     return;
 217   if (!allow_loading_) {
 218     NOTREACHED();
 219     return;
 220   }
 221
 222   if (premade_throttler_) {
 223     premade_throttler_->SetHiddenForPlaceholder(false /* hidden */);
 224     ReplacePlugin(premade_throttler_->GetWebPlugin());
 225     premade_throttler_ = nullptr;
 226   } else {
 227     ReplacePlugin(CreatePlugin());
 228   }
 229 }
 230
 231 void LoadablePluginPlaceholder::LoadCallback() {
 232   RenderThread::Get()->RecordAction(UserMetricsAction("Plugin_Load_Click"));
 233   // If the user specifically clicks on the plugin content's placeholder,
 234   // disable power saver throttling for this instance.
 235   MarkPluginEssential(PluginInstanceThrottler::UNTHROTTLE_METHOD_BY_CLICK);
 236   LoadPlugin();
 237 }
 238
 239 void LoadablePluginPlaceholder::DidFinishLoadingCallback() {
 240   finished_loading_ = true;
 241   if (message_.length() > 0)
 242     UpdateMessage();
 243
 244   // Wait for the placeholder to finish loading to hide the premade plugin.
 245   // This is necessary to prevent a flicker.
 246   if (premade_throttler_ && power_saver_enabled_)
 247     premade_throttler_->SetHiddenForPlaceholder(true /* hidden */);
 248
 249   // Set an attribute and post an event, so browser tests can wait for the
 250   // placeholder to be ready to receive simulated user input.
 251   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
 252           switches::kEnablePluginPlaceholderTesting)) {
 253     blink::WebElement element = plugin()->container()->element();
 254     element.setAttribute("placeholderLoaded", "true");
 255
 256     scoped_ptr<content::V8ValueConverter> converter(
 257         content::V8ValueConverter::create());
 258     base::StringValue value("placeholderLoaded");
 259     blink::WebSerializedScriptValue message_data =
 260         blink::WebSerializedScriptValue::serialize(converter->ToV8Value(
 261             &value, element.document().frame()->mainWorldScriptContext()));
 262
 263     blink::WebDOMEvent event = element.document().createEvent("MessageEvent");
 264     blink::WebDOMMessageEvent msg_event = event.to<blink::WebDOMMessageEvent>();
 265     msg_event.initMessageEvent("message",     // type
 266                                false,         // canBubble
 267                                false,         // cancelable
 268                                message_data,  // data
 269                                "",            // origin [*]
 270                                NULL,          // source [*]
 271                                "");           // lastEventId
 272     element.dispatchEvent(msg_event);
 273   }
 274 }
 275
 276 void LoadablePluginPlaceholder::SetPluginInfo(
 277     const content::WebPluginInfo& plugin_info) {
 278   plugin_info_ = plugin_info;
 279 }
 280
 281 const content::WebPluginInfo& LoadablePluginPlaceholder::GetPluginInfo() const {
 282   return plugin_info_;
 283 }
 284
 285 void LoadablePluginPlaceholder::SetIdentifier(const std::string& identifier) {
 286   identifier_ = identifier;
 287 }
 288
 289 const std::string& LoadablePluginPlaceholder::GetIdentifier() const {
 290   return identifier_;
 291 }
 292
 293 bool LoadablePluginPlaceholder::LoadingBlocked() const {
 294   DCHECK(allow_loading_);
 295   return is_blocked_for_background_tab_ || is_blocked_for_power_saver_poster_ ||
 296          is_blocked_for_prerendering_;
 297 }
 298
 299 }  // namespace plugins