web_ui_mojo_context_state.cc revision c5cede9ae108bb15f6b7a8aea21c7e1fefa2834c 
1// Copyright 2014 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/renderer/web_ui_mojo_context_state.h"
6
7#include "base/bind.h"
8#include "base/stl_util.h"
9#include "content/public/renderer/resource_fetcher.h"
10#include "content/renderer/web_ui_runner.h"
11#include "gin/converter.h"
12#include "gin/modules/module_registry.h"
13#include "gin/per_context_data.h"
14#include "gin/public/context_holder.h"
15#include "gin/try_catch.h"
16#include "mojo/bindings/js/core.h"
17#include "mojo/bindings/js/handle.h"
18#include "mojo/bindings/js/support.h"
19#include "third_party/WebKit/public/platform/WebURLResponse.h"
20#include "third_party/WebKit/public/web/WebFrame.h"
21#include "third_party/WebKit/public/web/WebScriptSource.h"
22
23using v8::Context;
24using v8::HandleScope;
25using v8::Isolate;
26using v8::Object;
27using v8::ObjectTemplate;
28using v8::Script;
29
30namespace content {
31
32namespace {
33
34// All modules have this prefixed to them when downloading.
35// TODO(sky): move this into some common place.
36const char kModulePrefix[] = "chrome://mojo/";
37
38void RunMain(base::WeakPtr<gin::Runner> runner,
39             mojo::ScopedMessagePipeHandle* handle,
40             v8::Handle<v8::Value> module) {
41  v8::Isolate* isolate = runner->GetContextHolder()->isolate();
42  v8::Handle<v8::Function> start;
43  CHECK(gin::ConvertFromV8(isolate, module, &start));
44  v8::Handle<v8::Value> args[] = {
45      gin::ConvertToV8(isolate, mojo::Handle(handle->release().value())) };
46  runner->Call(start, runner->global(), 1, args);
47}
48
49}  // namespace
50
51// WebUIMojo -------------------------------------------------------------------
52
53WebUIMojoContextState::WebUIMojoContextState(blink::WebFrame* frame,
54                                             v8::Handle<v8::Context> context)
55    : frame_(frame),
56      module_added_(false) {
57  gin::PerContextData* context_data = gin::PerContextData::From(context);
58  gin::ContextHolder* context_holder = context_data->context_holder();
59  runner_.reset(new WebUIRunner(frame_, context_holder));
60  gin::Runner::Scope scoper(runner_.get());
61  gin::ModuleRegistry::From(context)->AddObserver(this);
62  runner_->RegisterBuiltinModules();
63  gin::ModuleRegistry::InstallGlobals(context->GetIsolate(), context->Global());
64  // Warning |frame| may be destroyed.
65  // TODO(sky): add test for this.
66}
67
68WebUIMojoContextState::~WebUIMojoContextState() {
69  gin::Runner::Scope scoper(runner_.get());
70  gin::ModuleRegistry::From(
71      runner_->GetContextHolder()->context())->RemoveObserver(this);
72}
73
74void WebUIMojoContextState::SetHandle(mojo::ScopedMessagePipeHandle handle) {
75  gin::ContextHolder* context_holder = runner_->GetContextHolder();
76  mojo::ScopedMessagePipeHandle* passed_handle =
77      new mojo::ScopedMessagePipeHandle(handle.Pass());
78  gin::ModuleRegistry::From(context_holder->context())->LoadModule(
79      context_holder->isolate(),
80      "main",
81      base::Bind(RunMain, runner_->GetWeakPtr(), base::Owned(passed_handle)));
82}
83
84void WebUIMojoContextState::FetchModules(const std::vector<std::string>& ids) {
85  gin::Runner::Scope scoper(runner_.get());
86  gin::ContextHolder* context_holder = runner_->GetContextHolder();
87  gin::ModuleRegistry* registry = gin::ModuleRegistry::From(
88      context_holder->context());
89  for (size_t i = 0; i < ids.size(); ++i) {
90    if (fetched_modules_.find(ids[i]) == fetched_modules_.end() &&
91        registry->available_modules().count(ids[i]) == 0) {
92      FetchModule(ids[i]);
93    }
94  }
95}
96
97void WebUIMojoContextState::FetchModule(const std::string& id) {
98  const GURL url(kModulePrefix + id);
99  // TODO(sky): better error checks here?
100  DCHECK(url.is_valid() && !url.is_empty());
101  DCHECK(fetched_modules_.find(id) == fetched_modules_.end());
102  fetched_modules_.insert(id);
103  ResourceFetcher* fetcher = ResourceFetcher::Create(url);
104  module_fetchers_.push_back(fetcher);
105  fetcher->Start(frame_, blink::WebURLRequest::TargetIsScript,
106                 base::Bind(&WebUIMojoContextState::OnFetchModuleComplete,
107                            base::Unretained(this), fetcher));
108}
109
110void WebUIMojoContextState::OnFetchModuleComplete(
111    ResourceFetcher* fetcher,
112    const blink::WebURLResponse& response,
113    const std::string& data) {
114  DCHECK_EQ(kModulePrefix,
115      response.url().string().utf8().substr(0, arraysize(kModulePrefix) - 1));
116  const std::string module =
117      response.url().string().utf8().substr(arraysize(kModulePrefix) - 1);
118  // We can't delete fetch right now as the arguments to this function come from
119  // it and are used below. Instead use a scope_ptr to cleanup.
120  scoped_ptr<ResourceFetcher> deleter(fetcher);
121  module_fetchers_.weak_erase(
122      std::find(module_fetchers_.begin(), module_fetchers_.end(), fetcher));
123  if (data.empty()) {
124    NOTREACHED();
125    return;  // TODO(sky): log something?
126  }
127
128  runner_->Run(data, module);
129}
130
131void WebUIMojoContextState::OnDidAddPendingModule(
132    const std::string& id,
133    const std::vector<std::string>& dependencies) {
134  FetchModules(dependencies);
135
136  gin::ContextHolder* context_holder = runner_->GetContextHolder();
137  gin::ModuleRegistry* registry = gin::ModuleRegistry::From(
138      context_holder->context());
139  registry->AttemptToLoadMoreModules(context_holder->isolate());
140}
141
142}  // namespace content
143