web_ui_mojo_context_state.cc revision a1401311d1ab56c4ed0a474bd38c108f75cb0cd9 
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/support.h"
18#include "third_party/WebKit/public/platform/WebURLResponse.h"
19#include "third_party/WebKit/public/web/WebFrame.h"
20#include "third_party/WebKit/public/web/WebScriptSource.h"
21
22using v8::Context;
23using v8::HandleScope;
24using v8::Isolate;
25using v8::Object;
26using v8::ObjectTemplate;
27using v8::Script;
28
29namespace content {
30
31namespace {
32
33// All modules have this prefixed to them when downloading.
34// TODO(sky): move this into some common place.
35const char kModulePrefix[] = "chrome://mojo/";
36
37void RunMain(base::WeakPtr<gin::Runner> runner,
38             mojo::ScopedHandle* handle,
39             v8::Handle<v8::Value> module) {
40  v8::Isolate* isolate = runner->GetContextHolder()->isolate();
41  v8::Handle<v8::Function> start;
42  CHECK(gin::ConvertFromV8(isolate, module, &start));
43  v8::Handle<v8::Value> args[] = {
44      gin::ConvertToV8(isolate, handle->release().value()) };
45  runner->Call(start, runner->global(), 1, args);
46}
47
48}  // namespace
49
50// WebUIMojo -------------------------------------------------------------------
51
52WebUIMojoContextState::WebUIMojoContextState(blink::WebFrame* frame,
53                                             v8::Handle<v8::Context> context)
54    : frame_(frame),
55      module_added_(false) {
56  gin::PerContextData* context_data = gin::PerContextData::From(context);
57  gin::ContextHolder* context_holder = context_data->context_holder();
58  runner_.reset(new WebUIRunner(frame_, context_holder));
59  gin::Runner::Scope scoper(runner_.get());
60  gin::ModuleRegistry::From(context)->AddObserver(this);
61  runner_->RegisterBuiltinModules();
62  gin::ModuleRegistry::InstallGlobals(context->GetIsolate(), context->Global());
63  // Warning |frame| may be destroyed.
64  // TODO(sky): add test for this.
65}
66
67WebUIMojoContextState::~WebUIMojoContextState() {
68  gin::Runner::Scope scoper(runner_.get());
69  gin::ModuleRegistry::From(
70      runner_->GetContextHolder()->context())->RemoveObserver(this);
71}
72
73void WebUIMojoContextState::SetHandle(mojo::ScopedHandle handle) {
74  gin::ContextHolder* context_holder = runner_->GetContextHolder();
75  mojo::ScopedHandle* passed_handle = new mojo::ScopedHandle(handle.Pass());
76  gin::ModuleRegistry::From(context_holder->context())->LoadModule(
77      context_holder->isolate(),
78      "main",
79      base::Bind(RunMain, runner_->GetWeakPtr(), base::Owned(passed_handle)));
80}
81
82void WebUIMojoContextState::FetchModules(const std::vector<std::string>& ids) {
83  gin::Runner::Scope scoper(runner_.get());
84  gin::ContextHolder* context_holder = runner_->GetContextHolder();
85  gin::ModuleRegistry* registry = gin::ModuleRegistry::From(
86      context_holder->context());
87  for (size_t i = 0; i < ids.size(); ++i) {
88    if (fetched_modules_.find(ids[i]) == fetched_modules_.end() &&
89        registry->available_modules().count(ids[i]) == 0) {
90      FetchModule(ids[i]);
91    }
92  }
93}
94
95void WebUIMojoContextState::FetchModule(const std::string& id) {
96  const GURL url(kModulePrefix + id);
97  // TODO(sky): better error checks here?
98  DCHECK(url.is_valid() && !url.is_empty());
99  DCHECK(fetched_modules_.find(id) == fetched_modules_.end());
100  fetched_modules_.insert(id);
101  ResourceFetcher* fetcher = ResourceFetcher::Create(url);
102  module_fetchers_.push_back(fetcher);
103  fetcher->Start(frame_, blink::WebURLRequest::TargetIsScript,
104                 base::Bind(&WebUIMojoContextState::OnFetchModuleComplete,
105                            base::Unretained(this), fetcher));
106}
107
108void WebUIMojoContextState::OnFetchModuleComplete(
109    ResourceFetcher* fetcher,
110    const blink::WebURLResponse& response,
111    const std::string& data) {
112  DCHECK_EQ(kModulePrefix,
113      response.url().string().utf8().substr(0, arraysize(kModulePrefix) - 1));
114  const std::string module =
115      response.url().string().utf8().substr(arraysize(kModulePrefix));
116  // We can't delete fetch right now as the arguments to this function come from
117  // it and are used below. Instead use a scope_ptr to cleanup.
118  scoped_ptr<ResourceFetcher> deleter(fetcher);
119  module_fetchers_.weak_erase(
120      std::find(module_fetchers_.begin(), module_fetchers_.end(), fetcher));
121  if (data.empty()) {
122    NOTREACHED();
123    return;  // TODO(sky): log something?
124  }
125
126  runner_->Run(data, module);
127}
128
129void WebUIMojoContextState::OnDidAddPendingModule(
130    const std::string& id,
131    const std::vector<std::string>& dependencies) {
132  FetchModules(dependencies);
133
134  gin::ContextHolder* context_holder = runner_->GetContextHolder();
135  gin::ModuleRegistry* registry = gin::ModuleRegistry::From(
136      context_holder->context());
137  registry->AttemptToLoadMoreModules(context_holder->isolate());
138}
139
140}  // namespace content
141