Lazy load chrome.* APIs

chrome/renderer/extensions/dispatcher.cc

Index: chrome/renderer/extensions/dispatcher.cc
diff --git a/chrome/renderer/extensions/dispatcher.cc b/chrome/renderer/extensions/dispatcher.cc
index 94a90d6dd15e027f56171962a0c3e7041b9f7f32..7ac92d89cce73224511cff96a3ffc59a55506314 100644
--- a/chrome/renderer/extensions/dispatcher.cc
+++ b/chrome/renderer/extensions/dispatcher.cc
@@ -8,6 +8,7 @@
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/string_piece.h"
+#include "base/string_split.h"
 #include "chrome/common/child_process_logging.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
@@ -23,6 +24,7 @@
 #include "chrome/renderer/extensions/app_bindings.h"
 #include "chrome/renderer/extensions/app_runtime_custom_bindings.h"
 #include "chrome/renderer/extensions/app_window_custom_bindings.h"
+#include "chrome/renderer/extensions/binding_generating_native_handler.h"
 #include "chrome/renderer/extensions/chrome_v8_context.h"
 #include "chrome/renderer/extensions/chrome_v8_extension.h"
 #include "chrome/renderer/extensions/content_watcher.h"
@@ -38,7 +40,7 @@
 #include "chrome/renderer/extensions/media_galleries_custom_bindings.h"
 #include "chrome/renderer/extensions/miscellaneous_bindings.h"
 #include "chrome/renderer/extensions/module_system.h"
-#include "chrome/renderer/extensions/native_handler.h"
+#include "chrome/renderer/extensions/object_backed_native_handler.h"
 #include "chrome/renderer/extensions/page_actions_custom_bindings.h"
 #include "chrome/renderer/extensions/page_capture_custom_bindings.h"
 #include "chrome/renderer/extensions/request_sender.h"
@@ -89,10 +91,74 @@ static const char kEventDispatchFunction[] = "Event.dispatchEvent";
 static const char kOnUnloadEvent[] = "runtime.onSuspend";
 static const char kOnSuspendCanceledEvent[] = "runtime.onSuspendCanceled";
 
-class ChromeHiddenNativeHandler : public NativeHandler {
+static v8::Handle<v8::Object> GetOrCreateChrome(
+    v8::Handle<v8::Context> context) {
+  v8::Handle<v8::String> chrome_string(v8::String::New("chrome"));
+  v8::Handle<v8::Object> global(context->Global());
+  v8::Handle<v8::Value> chrome(global->Get(chrome_string));
+  if (chrome.IsEmpty() || chrome->IsUndefined()) {
+    v8::Handle<v8::Object> chrome_object(v8::Object::New());
+    global->Set(chrome_string, chrome_object);
+    return chrome_object;
+  }
+  CHECK(chrome->IsObject());
+  return chrome->ToObject();
+}
+
+class SchemaRegistryNativeHandler : public ObjectBackedNativeHandler {
+ public:
+  SchemaRegistryNativeHandler(V8SchemaRegistry* registry, v8::Isolate* isolate)
+      : ObjectBackedNativeHandler(isolate),
+        registry_(registry) {
+    RouteFunction("GetSchema",
+        base::Bind(&SchemaRegistryNativeHandler::GetSchema,
+                   base::Unretained(this)));
+  }
+
+ private:
+  v8::Handle<v8::Value> GetSchema(const v8::Arguments& args) {
+    return registry_->GetSchema(*v8::String::AsciiValue(args[0]));
+  }
+
+  V8SchemaRegistry* registry_;
+};
+
+class V8ContextNativeHandler : public ObjectBackedNativeHandler {
+ public:
+  V8ContextNativeHandler(ChromeV8Context* context, v8::Isolate* isolate)
+      : ObjectBackedNativeHandler(isolate),
+        context_(context) {
+    RouteFunction("GetAvailability",
+        base::Bind(&V8ContextNativeHandler::GetAvailability,
+                   base::Unretained(this)));
+  }
+
+ private:
+  v8::Handle<v8::Value> GetAvailability(const v8::Arguments& args) {
+    if (args.Length() < 1)
+      return v8::Undefined();

[not at google - send to devlin, 2013/02/13 01:45:49]

CHECK?

[cduvall, 2013/02/15 00:40:28]

Done.

+
+    std::string api_name = *v8::String::AsciiValue(args[0]->ToString());
+    v8::Handle<v8::Object> ret = v8::Object::New();
+    const std::set<std::string>& available_apis =
+        context_->GetAvailableExtensionAPIs();
+
+    if (available_apis.find(api_name) == available_apis.end()) {
+      ret->Set(v8::String::New("is_available"), v8::Boolean::New(false));
+      ret->Set(v8::String::New("message"), v8::String::New("SORRY!"));
+    } else {
+      ret->Set(v8::String::New("is_available"), v8::Boolean::New(true));
+    }

[not at google - send to devlin, 2013/02/13 01:45:49]

Heh - ok so let's add a GetAvailability method to ChromeV8Context, which returns
a Feature::Availability. Until everything is converted to Features we'll just
need to make up some generic error message (not as generic as "SORRY", but
something). Then when we convert to using a Feature for checking API
availability it will start working.

[cduvall, 2013/02/15 00:40:28]

Done.

+    return ret;
+  }
+
+  ChromeV8Context* context_;
+};
+
+class ChromeHiddenNativeHandler : public ObjectBackedNativeHandler {
  public:
   explicit ChromeHiddenNativeHandler(v8::Isolate* isolate)
-      : NativeHandler(isolate) {
+      : ObjectBackedNativeHandler(isolate) {
     RouteFunction("GetChromeHidden",
         base::Bind(&ChromeHiddenNativeHandler::GetChromeHidden,
                    base::Unretained(this)));
@@ -103,10 +169,23 @@ class ChromeHiddenNativeHandler : public NativeHandler {
   }
 };
 
-class PrintNativeHandler : public NativeHandler {
+class ChromeNativeHandler : public ObjectBackedNativeHandler {
+ public:
+  explicit ChromeNativeHandler(v8::Isolate* isolate)
+      : ObjectBackedNativeHandler(isolate) {
+    RouteFunction("GetChrome",
+        base::Bind(&ChromeNativeHandler::GetChrome, base::Unretained(this)));
+  }
+
+  v8::Handle<v8::Value> GetChrome(const v8::Arguments& args) {
+    return GetOrCreateChrome(v8::Context::GetCurrent());
+  }
+};
+
+class PrintNativeHandler : public ObjectBackedNativeHandler {
  public:
   explicit PrintNativeHandler(v8::Isolate* isolate)
-      : NativeHandler(isolate) {
+      : ObjectBackedNativeHandler(isolate) {
     RouteFunction("Print",
         base::Bind(&PrintNativeHandler::Print,
                    base::Unretained(this)));
@@ -238,10 +317,10 @@ class ProcessInfoNativeHandler : public ChromeV8Extension {
   bool send_request_disabled_;
 };
 
-class LoggingNativeHandler : public NativeHandler {
+class LoggingNativeHandler : public ObjectBackedNativeHandler {
  public:
   explicit LoggingNativeHandler(v8::Isolate* isolate)
-      : NativeHandler(isolate) {
+      : ObjectBackedNativeHandler(isolate) {
     RouteFunction("DCHECK",
         base::Bind(&LoggingNativeHandler::Dcheck,
                    base::Unretained(this)));
@@ -302,20 +381,6 @@ void InstallWebstoreBindings(ModuleSystem* module_system,
                               "chromeHiddenWebstore");
 }
 
-static v8::Handle<v8::Object> GetOrCreateChrome(
-    v8::Handle<v8::Context> context) {
-  v8::Handle<v8::String> chrome_string(v8::String::New("chrome"));
-  v8::Handle<v8::Object> global(context->Global());
-  v8::Handle<v8::Value> chrome(global->Get(chrome_string));
-  if (chrome.IsEmpty() || chrome->IsUndefined()) {
-    v8::Handle<v8::Object> chrome_object(v8::Object::New());
-    global->Set(chrome_string, chrome_object);
-    return chrome_object;
-  }
-  CHECK(chrome->IsObject());
-  return chrome->ToObject();
-}
-
 }  // namespace
 
 Dispatcher::Dispatcher()
@@ -560,6 +625,68 @@ bool Dispatcher::AllowScriptExtension(WebFrame* frame,
   return true;
 }
 
+v8::Handle<v8::Object> Dispatcher::GetOrCreateObject(
+    v8::Handle<v8::Object> object,
+    const std::string& field) {
+  v8::Handle<v8::String> key = v8::String::New(field.c_str());
+  // This little dance is for APIs that may be unavailable but have available
+  // children. For example, chrome.app can be unavailable, while
+  // chrome.app.runtime is available. The lazy getter for chrome.app must be
+  // deleted, so that there isn't an error when accessing chrome.app.runtime.
+  if (object->Has(key)) {
+    v8::Handle<v8::Object> existing =
+        v8::Handle<v8::Object>::Cast(object->Get(key));
+    if (!existing->IsUndefined())

[not at google - send to devlin, 2013/02/13 01:45:49]

koz@ can't remember which of the many existence checks you need here,
existing.IsEmpty()? existing->IsNull()?

Or is this check because lazy fields are set to undefined? Is there a stronger
check that would work here, like, module_system->HasLazyThingy(object, key) (the
implementation of which could use something like this check, or something
smarter).

I guess it's just a bit subtle for me.

[koz (OOO until 15th September), 2013/02/14 06:21:13]

Just existing.IsEmpty() to make sure the handle is valid, otherwise
dereferencing it will fail. V8 casts return empty handles if they fail.

[cduvall, 2013/02/15 00:40:28]

Done.

+      return existing;
+    else
+      object->Delete(key);
+  }
+
+  v8::Handle<v8::Object> new_object = v8::Object::New();
+  object->Set(key, new_object);
+  return new_object;
+}
+
+void Dispatcher::RegisterSchemaGeneratedBindings(
+    ModuleSystem* module_system,
+    ChromeV8Context* context,
+    v8::Handle<v8::Context> v8_context) {
+  std::set<std::string> apis =
+      ExtensionAPI::GetSharedInstance()->GetAllAPINames();
+  for (std::set<std::string>::iterator it = apis.begin();
+       it != apis.end(); ++it) {
+    const std::string& api_name = *it;
+
+    std::vector<std::string> split;
+    base::SplitString(api_name, '.', &split);
+
+    v8::Handle<v8::Object> bind_object = GetOrCreateChrome(v8_context);
+    for (size_t i = 0; i < split.size() - 1; ++i)
+      bind_object = GetOrCreateObject(bind_object, split[i]);
+
+    if (lazy_bindings_map_.find(api_name) != lazy_bindings_map_.end()) {
+      InstallBindings(module_system, v8_context, api_name);
+    } else if (!source_map_.Contains(api_name)) {
+      module_system->RegisterNativeHandler(
+          api_name,
+          scoped_ptr<NativeHandler>(new BindingGeneratingNativeHandler(
+              module_system,
+              v8_schema_registry(),
+              api_name,
+              "binding")));
+      module_system->SetNativeLazyField(bind_object,
+                                        split.back(),
+                                        api_name,
+                                        "binding");
+    } else {
+      module_system->SetLazyField(bind_object,
+                                  split.back(),
+                                  api_name,
+                                  "binding");
+    }
+  }
+}
+
 void Dispatcher::RegisterNativeHandlers(ModuleSystem* module_system,
                                         ChromeV8Context* context) {
   module_system->RegisterNativeHandler("event_bindings",
@@ -624,10 +751,8 @@ void Dispatcher::PopulateSourceMap() {
   source_map_.RegisterSource("event_bindings", IDR_EVENT_BINDINGS_JS);
   source_map_.RegisterSource("miscellaneous_bindings",
       IDR_MISCELLANEOUS_BINDINGS_JS);
-  source_map_.RegisterSource("schema_generated_bindings",
-      IDR_SCHEMA_GENERATED_BINDINGS_JS);
   source_map_.RegisterSource("json_schema", IDR_JSON_SCHEMA_JS);
-  source_map_.RegisterSource("apitest", IDR_EXTENSION_APITEST_JS);
+  source_map_.RegisterSource("test", IDR_EXTENSION_APITEST_JS);
 
   // Libraries.
   source_map_.RegisterSource("contentWatcher", IDR_CONTENT_WATCHER_JS);
@@ -691,10 +816,11 @@ void Dispatcher::PopulateSourceMap() {
   source_map_.RegisterSource("webRequestInternal",
                              IDR_WEB_REQUEST_INTERNAL_CUSTOM_BINDINGS_JS);
   source_map_.RegisterSource("webstore", IDR_WEBSTORE_CUSTOM_BINDINGS_JS);
+  source_map_.RegisterSource("binding", IDR_BINDING_JS);
 
   // Platform app sources that are not API-specific..
   source_map_.RegisterSource("tagWatcher", IDR_TAG_WATCHER_JS);
-  source_map_.RegisterSource("webview", IDR_WEB_VIEW_JS);
+  source_map_.RegisterSource("web_view", IDR_WEB_VIEW_JS);
   source_map_.RegisterSource("denyWebview", IDR_WEB_VIEW_DENY_JS);
   source_map_.RegisterSource("platformApp", IDR_PLATFORM_APP_JS);
   source_map_.RegisterSource("injectAppTitlebar", IDR_INJECT_APP_TITLEBAR_JS);
@@ -760,7 +886,7 @@ void Dispatcher::DidCreateScriptContext(
       new ChromeV8Context(v8_context, frame, extension, context_type);
   v8_context_set_.Add(context);
 
-  scoped_ptr<ModuleSystem> module_system(new ModuleSystem(v8_context,
+  scoped_ptr<ModuleSystem> module_system(new ModuleSystem(context,
                                                           &source_map_));
   // Enable natives in startup.
   ModuleSystem::NativesEnabledScope natives_enabled_scope(module_system.get());
@@ -768,6 +894,8 @@ void Dispatcher::DidCreateScriptContext(
   RegisterNativeHandlers(module_system.get(), context);
 
   v8::Isolate* isolate = v8_context->GetIsolate();
+  module_system->RegisterNativeHandler("chrome",
+      scoped_ptr<NativeHandler>(new ChromeNativeHandler(isolate)));
   module_system->RegisterNativeHandler("chrome_hidden",
       scoped_ptr<NativeHandler>(new ChromeHiddenNativeHandler(isolate)));
   module_system->RegisterNativeHandler("print",
@@ -776,6 +904,11 @@ void Dispatcher::DidCreateScriptContext(
       scoped_ptr<NativeHandler>(new LazyBackgroundPageNativeHandler(this)));
   module_system->RegisterNativeHandler("logging",
       scoped_ptr<NativeHandler>(new LoggingNativeHandler(isolate)));
+  module_system->RegisterNativeHandler("schema_registry",
+      scoped_ptr<NativeHandler>(
+          new SchemaRegistryNativeHandler(v8_schema_registry(), isolate)));
+  module_system->RegisterNativeHandler("v8_context",
+      scoped_ptr<NativeHandler>(new V8ContextNativeHandler(context, isolate)));
 
   int manifest_version = extension ? extension->manifest_version() : 1;
   bool send_request_disabled =
@@ -799,27 +932,25 @@ void Dispatcher::DidCreateScriptContext(
       InstallBindings(module_system.get(), v8_context, "app");
       InstallBindings(module_system.get(), v8_context, "webstore");
       break;
-
     case Feature::BLESSED_EXTENSION_CONTEXT:
     case Feature::UNBLESSED_EXTENSION_CONTEXT:
     case Feature::CONTENT_SCRIPT_CONTEXT: {
-      module_system->Require("miscellaneous_bindings");
-      module_system->Require("schema_generated_bindings");
-      module_system->Require("apitest");
+      if (extension && !extension->is_platform_app())
+        module_system->Require("miscellaneous_bindings");
 
       // TODO(kalman): move this code back out of the switch and execute it
       // regardless of |context_type|. ExtensionAPI knows how to return the
       // correct APIs, however, until it doesn't have a 2MB overhead we can't
       // load it in every process.
-      const std::set<std::string>& apis = context->GetAvailableExtensionAPIs();
-      for (std::set<std::string>::const_iterator i = apis.begin();
-           i != apis.end(); ++i) {
-        InstallBindings(module_system.get(), v8_context, *i);
-      }
-
+      RegisterSchemaGeneratedBindings(module_system.get(),
+                                      context,
+                                      v8_context);
       break;
     }
   }
+  // TODO(cduvall): Hack for loading JSON into chromeHidden (event.js).

[not at google - send to devlin, 2013/02/13 01:45:49]

what JSON?

[cduvall, 2013/02/15 00:40:28]

Clarified the comment.

+  // This is for ExtensionApiTest.Messaging.
+  module_system->Require("event_bindings");
 
   // Inject custom JS into the platform app context.
   if (IsWithinPlatformApp(frame))
@@ -827,7 +958,7 @@ void Dispatcher::DidCreateScriptContext(
 
   if (context_type == Feature::BLESSED_EXTENSION_CONTEXT) {
     bool has_permission = extension->HasAPIPermission(APIPermission::kWebView);
-    module_system->Require(has_permission ? "webview" : "denyWebview");
+    module_system->Require(has_permission ? "web_view" : "denyWebview");
   }
 
   context->set_module_system(module_system.Pass());