content/browser/accessibility/accessibility_ui.cc

   1 // Copyright (c) 2013 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 "content/browser/accessibility/accessibility_ui.h"
   6
   7 #include "base/bind.h"
   8 #include "base/bind_helpers.h"
   9 #include "base/json/json_writer.h"
  10 #include "base/strings/string_number_conversions.h"
  11 #include "base/strings/utf_string_conversions.h"
  12 #include "base/values.h"
  13 #include "content/browser/accessibility/accessibility_tree_formatter.h"
  14 #include "content/browser/accessibility/browser_accessibility_manager.h"
  15 #include "content/browser/accessibility/browser_accessibility_state_impl.h"
  16 #include "content/browser/renderer_host/render_widget_host_impl.h"
  17 #include "content/common/view_message_enums.h"
  18 #include "content/port/browser/render_widget_host_view_port.h"
  19 #include "content/public/browser/browser_thread.h"
  20 #include "content/public/browser/favicon_status.h"
  21 #include "content/public/browser/navigation_entry.h"
  22 #include "content/public/browser/render_process_host.h"
  23 #include "content/public/browser/render_view_host.h"
  24 #include "content/public/browser/render_widget_host.h"
  25 #include "content/public/browser/render_widget_host_iterator.h"
  26 #include "content/public/browser/web_contents.h"
  27 #include "content/public/browser/web_ui_data_source.h"
  28 #include "content/public/common/url_constants.h"
  29 #include "grit/content_resources.h"
  30 #include "net/base/escape.h"
  31
  32 static const char kDataFile[] = "targets-data.json";
  33
  34 static const char kProcessIdField[]  = "processId";
  35 static const char kRouteIdField[]  = "routeId";
  36 static const char kUrlField[]  = "url";
  37 static const char kNameField[]  = "name";
  38 static const char kFaviconUrlField[] = "favicon_url";
  39 static const char kPidField[]  = "pid";
  40 static const char kAccessibilityModeField[] = "a11y_mode";
  41
  42 namespace content {
  43
  44 namespace {
  45
  46 base::DictionaryValue* BuildTargetDescriptor(
  47     const GURL& url,
  48     const std::string& name,
  49     const GURL& favicon_url,
  50     int process_id,
  51     int route_id,
  52     AccessibilityMode accessibility_mode,
  53     base::ProcessHandle handle = base::kNullProcessHandle) {
  54   base::DictionaryValue* target_data = new base::DictionaryValue();
  55   target_data->SetInteger(kProcessIdField, process_id);
  56   target_data->SetInteger(kRouteIdField, route_id);
  57   target_data->SetString(kUrlField, url.spec());
  58   target_data->SetString(kNameField, net::EscapeForHTML(name));
  59   target_data->SetInteger(kPidField, base::GetProcId(handle));
  60   target_data->SetString(kFaviconUrlField, favicon_url.spec());
  61   target_data->SetInteger(kAccessibilityModeField,
  62                           accessibility_mode);
  63   return target_data;
  64 }
  65
  66 base::DictionaryValue* BuildTargetDescriptor(RenderViewHost* rvh) {
  67   WebContents* web_contents = WebContents::FromRenderViewHost(rvh);
  68   std::string title;
  69   RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(rvh);
  70   AccessibilityMode accessibility_mode = rwhi->accessibility_mode();
  71
  72   GURL url;
  73   GURL favicon_url;
  74   if (web_contents) {
  75     // TODO(nasko): Fix the following code to use a consistent set of data
  76     // across the URL, title, and favicon.
  77     url = web_contents->GetURL();
  78     title = base::UTF16ToUTF8(web_contents->GetTitle());
  79     NavigationController& controller = web_contents->GetController();
  80     NavigationEntry* entry = controller.GetVisibleEntry();
  81     if (entry != NULL && entry->GetURL().is_valid())
  82       favicon_url = entry->GetFavicon().url;
  83   }
  84
  85   return BuildTargetDescriptor(url,
  86                                title,
  87                                favicon_url,
  88                                rvh->GetProcess()->GetID(),
  89                                rvh->GetRoutingID(),
  90                                accessibility_mode);
  91 }
  92
  93 void SendTargetsData(
  94     const WebUIDataSource::GotDataCallback& callback) {
  95   scoped_ptr<base::ListValue> rvh_list(new base::ListValue());
  96
  97   scoped_ptr<RenderWidgetHostIterator> widgets(
  98       RenderWidgetHost::GetRenderWidgetHosts());
  99   while (RenderWidgetHost* widget = widgets->GetNextHost()) {
 100     // Ignore processes that don't have a connection, such as crashed tabs.
 101     if (!widget->GetProcess()->HasConnection())
 102       continue;
 103     if (!widget->IsRenderView())
 104         continue;
 105
 106     RenderViewHost* rvh = RenderViewHost::From(widget);
 107     rvh_list->Append(BuildTargetDescriptor(rvh));
 108   }
 109
 110   scoped_ptr<base::DictionaryValue> data(new base::DictionaryValue());
 111   data->Set("list", rvh_list.release());
 112   scoped_ptr<base::FundamentalValue> a11y_mode(new base::FundamentalValue(
 113       BrowserAccessibilityStateImpl::GetInstance()->accessibility_mode()));
 114   data->Set("global_a11y_mode", a11y_mode.release());
 115
 116   std::string json_string;
 117   base::JSONWriter::Write(data.get(), &json_string);
 118
 119   callback.Run(base::RefCountedString::TakeString(&json_string));
 120 }
 121
 122 bool HandleRequestCallback(
 123     const std::string& path,
 124     const WebUIDataSource::GotDataCallback& callback) {
 125   if (path != kDataFile)
 126     return false;
 127
 128   SendTargetsData(callback);
 129   return true;
 130 }
 131
 132 }  // namespace
 133
 134 AccessibilityUI::AccessibilityUI(WebUI* web_ui)
 135   : WebUIController(web_ui) {
 136   // Set up the chrome://accessibility source.
 137   WebUIDataSource* html_source =
 138       WebUIDataSource::Create(kChromeUIAccessibilityHost);
 139   html_source->SetUseJsonJSFormatV2();
 140
 141   web_ui->RegisterMessageCallback(
 142       "toggleAccessibility",
 143       base::Bind(&AccessibilityUI::ToggleAccessibility,
 144                base::Unretained(this)));
 145   web_ui->RegisterMessageCallback(
 146       "toggleGlobalAccessibility",
 147       base::Bind(&AccessibilityUI::ToggleGlobalAccessibility,
 148                base::Unretained(this)));
 149   web_ui->RegisterMessageCallback(
 150       "requestAccessibilityTree",
 151       base::Bind(&AccessibilityUI::RequestAccessibilityTree,
 152                  base::Unretained(this)));
 153
 154   // Add required resources.
 155   html_source->SetJsonPath("strings.js");
 156   html_source->AddResourcePath("accessibility.css", IDR_ACCESSIBILITY_CSS);
 157   html_source->AddResourcePath("accessibility.js", IDR_ACCESSIBILITY_JS);
 158   html_source->SetDefaultResource(IDR_ACCESSIBILITY_HTML);
 159   html_source->SetRequestFilter(base::Bind(&HandleRequestCallback));
 160
 161   BrowserContext* browser_context =
 162     web_ui->GetWebContents()->GetBrowserContext();
 163   WebUIDataSource::Add(browser_context, html_source);
 164 }
 165
 166 AccessibilityUI::~AccessibilityUI() {
 167 }
 168
 169 void AccessibilityUI::ToggleAccessibility(const base::ListValue* args) {
 170   std::string process_id_str;
 171   std::string route_id_str;
 172   int process_id;
 173   int route_id;
 174   CHECK(args->GetSize() == 2);
 175   CHECK(args->GetString(0, &process_id_str));
 176   CHECK(args->GetString(1, &route_id_str));
 177   CHECK(base::StringToInt(process_id_str,
 178                           &process_id));
 179   CHECK(base::StringToInt(route_id_str, &route_id));
 180
 181   RenderViewHost* rvh = RenderViewHost::FromID(process_id, route_id);
 182   if (!rvh)
 183     return;
 184   RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(rvh);
 185   if (!rwhi)
 186     return;
 187   AccessibilityMode mode = rwhi->accessibility_mode();
 188   if (mode == AccessibilityModeOff)
 189     rwhi->SetAccessibilityMode(AccessibilityModeComplete);
 190   else
 191     rwhi->SetAccessibilityMode(AccessibilityModeOff);
 192 }
 193
 194 void AccessibilityUI::ToggleGlobalAccessibility(const base::ListValue* args) {
 195   BrowserAccessibilityStateImpl* state =
 196       BrowserAccessibilityStateImpl::GetInstance();
 197   AccessibilityMode mode = state->accessibility_mode();
 198   AccessibilityMode new_mode = (mode == AccessibilityModeOff
 199                                 ? AccessibilityModeComplete
 200                                 : AccessibilityModeOff);
 201   state->SetAccessibilityMode(new_mode);
 202 }
 203
 204 void AccessibilityUI::RequestAccessibilityTree(const base::ListValue* args) {
 205   std::string process_id_str;
 206   std::string route_id_str;
 207   int process_id;
 208   int route_id;
 209   CHECK(args->GetSize() == 2);
 210   CHECK(args->GetString(0, &process_id_str));
 211   CHECK(args->GetString(1, &route_id_str));
 212   CHECK(base::StringToInt(process_id_str, &process_id));
 213   CHECK(base::StringToInt(route_id_str, &route_id));
 214
 215   RenderViewHost* rvh = RenderViewHost::FromID(process_id, route_id);
 216   if (!rvh) {
 217     scoped_ptr<base::DictionaryValue> result(new base::DictionaryValue());
 218     result->SetInteger(kProcessIdField, process_id);
 219     result->SetInteger(kRouteIdField, route_id);
 220     result->Set("error", new base::StringValue("Renderer no longer exists."));
 221     web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 222     return;
 223   }
 224
 225   scoped_ptr<base::DictionaryValue> result(BuildTargetDescriptor(rvh));
 226   RenderWidgetHostViewPort* host_view = static_cast<RenderWidgetHostViewPort*>(
 227       WebContents::FromRenderViewHost(rvh)->GetRenderWidgetHostView());
 228   if (!host_view) {
 229     result->Set("error",
 230                 new base::StringValue("Could not get accessibility tree."));
 231     web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 232     return;
 233   }
 234   scoped_ptr<AccessibilityTreeFormatter> formatter(
 235       AccessibilityTreeFormatter::Create(rvh));
 236   base::string16 accessibility_contents_utf16;
 237   BrowserAccessibilityManager* manager =
 238       host_view->GetBrowserAccessibilityManager();
 239   if (!manager) {
 240     result->Set("error",
 241                 new base::StringValue("Could not get accessibility tree."));
 242     web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 243     return;
 244   }
 245   std::vector<AccessibilityTreeFormatter::Filter> filters;
 246   filters.push_back(AccessibilityTreeFormatter::Filter(
 247       base::ASCIIToUTF16("*"),
 248       AccessibilityTreeFormatter::Filter::ALLOW));
 249   formatter->SetFilters(filters);
 250   formatter->FormatAccessibilityTree(&accessibility_contents_utf16);
 251
 252   result->Set("tree",
 253               new base::StringValue(
 254                   base::UTF16ToUTF8(accessibility_contents_utf16)));
 255   web_ui()->CallJavascriptFunction("accessibility.showTree", *(result.get()));
 256 }
 257
 258 }  // namespace content