[Extensions Bindings] Add a bindings/ subdirectory under renderer

extensions/renderer/api_request_handler.cc

-// Copyright 2016 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 "extensions/renderer/api_request_handler.h"
-
-#include "base/bind.h"
-#include "base/guid.h"
-#include "base/memory/ptr_util.h"
-#include "base/values.h"
-#include "content/public/child/v8_value_converter.h"
-#include "gin/converter.h"
-#include "gin/data_object_builder.h"
-#include "third_party/WebKit/public/web/WebScopedUserGesture.h"
-#include "third_party/WebKit/public/web/WebUserGestureIndicator.h"
-
-namespace extensions {
-
-APIRequestHandler::Request::Request() {}
-APIRequestHandler::Request::~Request() = default;
-
-APIRequestHandler::PendingRequest::PendingRequest(
-    v8::Isolate* isolate,
-    v8::Local<v8::Function> callback,
-    v8::Local<v8::Context> context,
-    const std::vector<v8::Local<v8::Value>>& local_callback_args)
-    : isolate(isolate),
-      context(isolate, context),
-      callback(isolate, callback),
-      user_gesture_token(
-          blink::WebUserGestureIndicator::CurrentUserGestureToken()) {
-  if (!local_callback_args.empty()) {
-    callback_arguments.reserve(local_callback_args.size());
-    for (const auto& arg : local_callback_args)
-      callback_arguments.push_back(v8::Global<v8::Value>(isolate, arg));
-  }
-}
-
-APIRequestHandler::PendingRequest::~PendingRequest() {}
-APIRequestHandler::PendingRequest::PendingRequest(PendingRequest&&) = default;
-APIRequestHandler::PendingRequest& APIRequestHandler::PendingRequest::operator=(
-    PendingRequest&&) = default;
-
-APIRequestHandler::APIRequestHandler(const SendRequestMethod& send_request,
-                                     const CallJSFunction& call_js,
-                                     APILastError last_error)
-    : send_request_(send_request),
-      call_js_(call_js),
-      last_error_(std::move(last_error)) {}
-
-APIRequestHandler::~APIRequestHandler() {}
-
-int APIRequestHandler::StartRequest(v8::Local<v8::Context> context,
-                                    const std::string& method,
-                                    std::unique_ptr<base::ListValue> arguments,
-                                    v8::Local<v8::Function> callback,
-                                    v8::Local<v8::Function> custom_callback,
-                                    binding::RequestThread thread) {
-  auto request = base::MakeUnique<Request>();
-
-  // The request id is primarily used in the renderer to associate an API
-  // request with the associated callback, but it's also used in the browser as
-  // an identifier for the extension function (e.g. by the pageCapture API).
-  // TODO(devlin): We should probably fix this, since the request id is only
-  // unique per-isolate, rather than globally.
-  // TODO(devlin): We could *probably* get away with just using an integer
-  // here, but it's a little less foolproof. How slow is GenerateGUID? Should
-  // we use that instead? It means updating the IPC
-  // (ExtensionHostMsg_Request).
-  // base::UnguessableToken is another good option.
-  int request_id = next_request_id_++;
-  request->request_id = request_id;
-
-  if (!custom_callback.IsEmpty() || !callback.IsEmpty()) {
-    v8::Isolate* isolate = context->GetIsolate();
-    // In the JS bindings, custom callbacks are called with the arguments of
-    // name, the full request object (see below), the original callback, and
-    // the responses from the API. The responses from the API are handled by the
-    // APIRequestHandler, but we need to curry in the other values.
-    std::vector<v8::Local<v8::Value>> callback_args;
-    if (!custom_callback.IsEmpty()) {
-      // TODO(devlin): The |request| object in the JS bindings includes
-      // properties for callback, callbackSchema, args, stack, id, and
-      // customCallback. Of those, it appears that we only use stack, args, and
-      // id (since callback is curried in separately). We may be able to update
-      // bindings to get away from some of those. For now, just pass in an
-      // object with the request id.
-      v8::Local<v8::Object> request =
-          gin::DataObjectBuilder(isolate).Set("id", request_id).Build();
-      v8::Local<v8::Value> callback_to_pass = callback;
-      if (callback_to_pass.IsEmpty())
-        callback_to_pass = v8::Undefined(isolate);
-      callback_args = {gin::StringToSymbol(isolate, method), request,
-                       callback_to_pass};
-      callback = custom_callback;
-    }
-
-    request->has_callback = true;
-    pending_requests_.insert(std::make_pair(
-        request_id, PendingRequest(isolate, callback, context, callback_args)));
-  }
-
-  request->has_user_gesture =
-      blink::WebUserGestureIndicator::IsProcessingUserGestureThreadSafe();
-  request->arguments = std::move(arguments);
-  request->method_name = method;
-  request->thread = thread;
-
-  send_request_.Run(std::move(request), context);
-  return request_id;
-}
-
-void APIRequestHandler::CompleteRequest(int request_id,
-                                        const base::ListValue& response_args,
-                                        const std::string& error) {
-  auto iter = pending_requests_.find(request_id);
-  // The request may have been removed if the context was invalidated before a
-  // response is ready.
-  if (iter == pending_requests_.end())
-    return;
-
-  PendingRequest pending_request = std::move(iter->second);
-  pending_requests_.erase(iter);
-
-  v8::Isolate* isolate = pending_request.isolate;
-  v8::HandleScope handle_scope(isolate);
-  v8::Local<v8::Context> context = pending_request.context.Get(isolate);
-  v8::Context::Scope context_scope(context);
-  std::unique_ptr<content::V8ValueConverter> converter =
-      content::V8ValueConverter::Create();
-  std::vector<v8::Local<v8::Value>> args;
-  args.reserve(response_args.GetSize() +
-               pending_request.callback_arguments.size());
-  for (const auto& arg : pending_request.callback_arguments)
-    args.push_back(arg.Get(isolate));
-  for (const auto& arg : response_args)
-    args.push_back(converter->ToV8Value(&arg, context));
-
-  blink::WebScopedUserGesture user_gesture(pending_request.user_gesture_token);
-  if (!error.empty())
-    last_error_.SetError(context, error);
-
-  // args.size() is converted to int, but args is controlled by chrome and is
-  // never close to std::numeric_limits<int>::max.
-  call_js_.Run(pending_request.callback.Get(isolate), context, args.size(),
-               args.data());
-
-  if (!error.empty())
-    last_error_.ClearError(context, true);
-}
-
-int APIRequestHandler::AddPendingRequest(v8::Local<v8::Context> context,
-                                         v8::Local<v8::Function> callback) {
-  int request_id = next_request_id_++;
-  pending_requests_.emplace(
-      request_id, PendingRequest(context->GetIsolate(), callback, context,
-                                 std::vector<v8::Local<v8::Value>>()));
-  return request_id;
-}
-
-void APIRequestHandler::InvalidateContext(v8::Local<v8::Context> context) {
-  for (auto iter = pending_requests_.begin();
-       iter != pending_requests_.end();) {
-    if (iter->second.context == context)
-      iter = pending_requests_.erase(iter);
-    else
-      ++iter;
-  }
-}
-
-std::set<int> APIRequestHandler::GetPendingRequestIdsForTesting() const {
-  std::set<int> result;
-  for (const auto& pair : pending_requests_)
-    result.insert(pair.first);
-  return result;
-}
-
-}  // namespace extensions