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