Extract ExtensionRequestSender from SchemaGeneratedBindings.

chrome/renderer/extensions/extension_request_sender.cc

+// Copyright (c) 2012 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 "chrome/renderer/extensions/extension_request_sender.h"
+
+#include "base/values.h"
+#include "chrome/common/extensions/extension_messages.h"
+#include "chrome/renderer/extensions/chrome_v8_context.h"
+#include "chrome/renderer/extensions/chrome_v8_context_set.h"
+#include "chrome/renderer/extensions/extension_dispatcher.h"
+#include "content/public/renderer/render_view.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebSecurityOrigin.h"
+
+// Contains info relevant to a pending API request.
+struct PendingRequest {
+ public :
+  PendingRequest(v8::Persistent<v8::Context> context, const std::string& name,
+                 const std::string& extension_id)
+      : context(context), name(name), extension_id(extension_id) {
+  }
+
+  ~PendingRequest() {
+    context.Dispose();
+  }
+
+  v8::Persistent<v8::Context> context;
+  std::string name;
+  std::string extension_id;
+};
+
+ExtensionRequestSender::ExtensionRequestSender(
+    ExtensionDispatcher* extension_dispatcher,
+    ChromeV8ContextSet* context_set)
+    : extension_dispatcher_(extension_dispatcher),
+      context_set_(context_set) {
+}
+
+ExtensionRequestSender::~ExtensionRequestSender() {
+}
+
+void ExtensionRequestSender::InsertRequest(int request_id,
+                                           PendingRequest* pending_request) {
+  DCHECK(pending_requests.count(request_id) == 0);

[not at google - send to devlin, 2012/03/30 03:14:31]

DCHECK_EQ

[koz (OOO until 15th September), 2012/04/03 00:15:17]

Done.

+  pending_requests_[request_id].reset(pending_request);

[not at google - send to devlin, 2012/03/30 03:14:31]

so much overkill having this in a separate method though, only used in 1 place
and it's a 1-line function.

[koz (OOO until 15th September), 2012/04/03 00:15:17]

Eh, it makes the code a bit more readable, I think. No messing around with
linked_ptrs or iterators.

+}
+
+PendingRequest* ExtensionRequestSender::GetPendingRequest(int request_id) {
+  PendingRequestMap::iterator i = pending_requests_.find(request_id);
+  if (i == pending_requests_.end()) {
+    return NULL;
+  }
+  return i->second.get();
+}
+
+void ExtensionRequestSender::RemoveRequest(int request_id) {
+  PendingRequest* request = GetPendingRequest(request_id);
+  if (!request)
+    return;
+  pending_requests_.erase(request_id);
+}
+
+void ExtensionRequestSender::StartRequest(
+    const std::string& name,
+    int request_id,
+    bool has_callback,
+    bool for_io_thread,
+    base::ListValue* value_args) {
+  ChromeV8Context* current_context = context_set_->GetCurrent();
+  if (!current_context)
+    return;
+
+  // Get the current RenderView so that we can send a routed IPC message from
+  // the correct source.
+  content::RenderView* renderview = current_context->GetRenderView();
+  if (!renderview)
+    return;
+
+  const std::set<std::string>& function_names =
+      extension_dispatcher_->function_names();
+  if (function_names.find(name) == function_names.end()) {
+    NOTREACHED() << "Unexpected function " << name <<
+        ". Did you remember to register it with ExtensionFunctionRegistry?";
+    return;
+  }
+
+  if (!extension_dispatcher_->CheckCurrentContextAccessToExtensionAPI(name))
+    return;

[not at google - send to devlin, 2012/03/30 03:14:31]

this one is a bit funny, the JS side of things should now have enough
permissions checking so that this never happens. I think. I wouldn't trust it
enough to not have this check though, or to make it a CHECK. Maybe a TODO to
make it into a CHECK?

[koz (OOO until 15th September), 2012/04/03 00:15:17]

Done.

+
+  GURL source_url;
+  WebKit::WebSecurityOrigin source_origin;
+  WebKit::WebFrame* webframe = current_context->web_frame();
+  if (webframe) {
+    source_url = webframe->document().url();
+    source_origin = webframe->document().securityOrigin();
+  }
+
+  v8::Persistent<v8::Context> v8_context =
+      v8::Persistent<v8::Context>::New(v8::Context::GetCurrent());
+  DCHECK(!v8_context.IsEmpty());
+  InsertRequest(request_id, new PendingRequest(
+      v8_context, name, current_context->extension_id()));
+
+  ExtensionHostMsg_Request_Params params;
+  params.name = name;
+  params.arguments.Swap(value_args);
+  params.extension_id = current_context->extension_id();
+  params.source_url = source_url;
+  params.source_origin = source_origin.toString();
+  params.request_id = request_id;
+  params.has_callback = has_callback;
+  params.user_gesture =
+      webframe ? webframe->isProcessingUserGesture() : false;
+  if (for_io_thread) {
+    renderview->Send(new ExtensionHostMsg_RequestForIOThread(
+        renderview->GetRoutingID(), params));
+  } else {
+    renderview->Send(new ExtensionHostMsg_Request(
+        renderview->GetRoutingID(), params));
+  }
+}
+
+void ExtensionRequestSender::HandleResponse(int request_id,
+                                            bool success,
+                                            const std::string& response,
+                                            const std::string& error) {
+  PendingRequest* request = GetPendingRequest(request_id);

[not at google - send to devlin, 2012/03/30 03:14:31]

Could this be RemovePendingRequest and not have GetPendingRequest()? Seems like
all we ever want to do is remove it if it's there.

Related comment, the thing on line 139 worries me, if the frame "went away" do
we want to leak these request objects? Confused...

[koz (OOO until 15th September), 2012/04/03 00:15:17]

Done.

+  if (!request) {
+    // This should not be able to happen since we only remove requests when they
+    // are handled.
+    LOG(ERROR) << "Could not find specified request id: " << request_id;
+    return;
+  }
+
+  ChromeV8Context* v8_context = context_set_->GetByV8Context(request->context);
+  if (!v8_context)
+    return;  // The frame went away.
+
+  v8::HandleScope handle_scope;
+  v8::Handle<v8::Value> argv[5];
+  argv[0] = v8::Integer::New(request_id);
+  argv[1] = v8::String::New(request->name.c_str());
+  argv[2] = v8::Boolean::New(success);
+  argv[3] = v8::String::New(response.c_str());
+  argv[4] = v8::String::New(error.c_str());
+
+  v8::Handle<v8::Value> retval;
+  CHECK(v8_context->CallChromeHiddenMethod("handleResponse",
+                                           arraysize(argv),
+                                           argv,
+                                           &retval));
+  // In debug, the js will validate the callback parameters and return a
+  // string if a validation error has occured.
+#ifndef NDEBUG
+  if (!retval.IsEmpty() && !retval->IsUndefined()) {
+    std::string error = *v8::String::AsciiValue(retval);
+    DCHECK(false) << error;
+  }
+#endif
+
+  RemoveRequest(request_id);
+}