Web MIDI: implement permission infobar

chrome/browser/media/chrome_midi_permission_context.cc

+// Copyright 2013 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/browser/media/chrome_midi_permission_context.h"
+
+#include "base/prefs/pref_service.h"
+#include "chrome/browser/chrome_notification_types.h"
+#include "chrome/browser/content_settings/host_content_settings_map.h"
+#include "chrome/browser/content_settings/permission_request_id.h"
+#include "chrome/browser/content_settings/tab_specific_content_settings.h"
+#include "chrome/browser/infobars/infobar_service.h"
+#include "chrome/browser/media/midi_permission_infobar_delegate.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/tab_contents/tab_util.h"
+#include "chrome/common/pref_names.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/notification_source.h"
+#include "content/public/browser/web_contents.h"
+
+ChromeMIDIPermissionContext::ChromeMIDIPermissionContext(Profile* profile)
+    : profile_(profile),
+      shutting_down_(false) {
+}
+
+ChromeMIDIPermissionContext::~ChromeMIDIPermissionContext() {
+  DCHECK(!permission_queue_controller_.get());

[Bernhard Bauer, 2013/07/31 15:35:39]

You can leave out the .get(); scoped_ptr has an implicit conversion to bool.

[Takashi Toyoshima, 2013/08/01 07:43:09]

Done.

+}
+
+void ChromeMIDIPermissionContext::RequestMIDISysExPermission(
+    int render_process_id,
+    int render_view_id,
+    const GURL& requesting_frame,
+    const content::BrowserContext::MIDISysExPermissionCallback& callback) {
+  if (!content::BrowserThread::CurrentlyOn(content::BrowserThread::UI)) {

[Bernhard Bauer, 2013/07/31 15:35:39]

I'm not a big fan of this construct. The calling code should know whether it's
on the UI thread or not, so it could call the right method which DCHECKs that.

Hmm, isn't this always called on the UI thread anyway?

[Takashi Toyoshima, 2013/08/01 07:43:09]

No. This function is always called from *IO* thread though the content API, and
here changed to UI thread.

[Bernhard Bauer, 2013/08/01 08:21:27]

Uhh... Isn't this called from
(OffTheRecord)ProfileImpl::RequestMIDISysExPermission()? BrowserContext lives on
the UI thread, so you'd either need to jump to the UI thread beforehand, or pass
the object to the IO thread. I can't find code calling
BrowserContext::RequestMIDISysExPermission() in codesearch, is that in a pending
CL somewhere? I'd be interested in finding out where you get the BrowserContext
pointer from.

(As an aside, this is why I'm not in favor of these catch-all thread hops: If
you document your assumptions with DCHECKs, you find out when they're not the
case :) ).

[Takashi Toyoshima, 2013/08/01 09:29:45]

The caller code is introduced in this change.
Please see the diff of profile_impl.cc and off_the_record_profile_impl.cc.

[Bernhard Bauer, 2013/08/01 11:14:02]

Yes, but who calls BrowserContext::RequestMIDISysExPermission() (which is the
method overridden in ProfileImpl and OffTheRecordProfileImpl)?

+    content::BrowserThread::PostTask(
+        content::BrowserThread::UI, FROM_HERE,
+        base::Bind(&ChromeMIDIPermissionContext::RequestMIDISysExPermission,
+                   this,
+                   render_process_id,
+                   render_view_id,
+                   requesting_frame,
+                   callback));
+    return;
+  }
+
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  if (shutting_down_)
+    return;
+
+  // TODO(toyoshim): Support Extension's manifest declared permission.
+  // http://crbug.com/266338 .
+
+  content::WebContents* web_contents =
+    tab_util::GetWebContentsByID(render_process_id, render_view_id);
+
+  // The page doesn't exist any more.
+  if (!web_contents)
+    return;
+
+  const PermissionRequestID id(render_process_id, render_view_id, 0);
+
+  GURL embedder = web_contents->GetURL();
+  if (!requesting_frame.is_valid() || !embedder.is_valid()) {
+    LOG(WARNING) << "Attempt to use MIDI sysex from an invalid URL: "
+                 << requesting_frame << "," << embedder
+                 << " (Web MIDI is not supported in popups)";
+    PermissionDecided(id, requesting_frame, embedder, callback, false);
+    return;
+  }
+
+  DecidePermission(id, requesting_frame, embedder, callback);
+}
+
+void ChromeMIDIPermissionContext::DecidePermission(
+    const PermissionRequestID& id,
+    const GURL& requesting_frame,
+    const GURL& embedder,
+    const content::BrowserContext::MIDISysExPermissionCallback& callback) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+
+  ContentSetting content_setting =
+      profile_->GetHostContentSettingsMap()->GetContentSetting(
+          requesting_frame,
+          embedder,
+          CONTENT_SETTINGS_TYPE_MIDI_SYSEX,
+          std::string());
+  switch (content_setting) {
+    case CONTENT_SETTING_BLOCK:
+      PermissionDecided(id, requesting_frame, embedder, callback, false);
+      break;
+    case CONTENT_SETTING_ALLOW:
+      PermissionDecided(id, requesting_frame, embedder, callback, true);
+      break;
+    default:
+      QueueController()->CreateInfoBarRequest(
+          id, requesting_frame, embedder, base::Bind(
+              &ChromeMIDIPermissionContext::NotifyPermissionSet,
+              base::Unretained(this), id, requesting_frame, callback));
+  }
+}
+
+void ChromeMIDIPermissionContext::ShutdownOnUIThread() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  permission_queue_controller_.reset();
+  shutting_down_ = true;
+}
+
+void ChromeMIDIPermissionContext::PermissionDecided(
+    const PermissionRequestID& id,
+    const GURL& requesting_frame,
+    const GURL& embedder,
+    const content::BrowserContext::MIDISysExPermissionCallback& callback,
+    bool allowed) {
+  NotifyPermissionSet(id, requesting_frame, callback, allowed);
+}
+
+void ChromeMIDIPermissionContext::NotifyPermissionSet(
+    const PermissionRequestID& id,
+    const GURL& requesting_frame,
+    const content::BrowserContext::MIDISysExPermissionCallback& callback,
+    bool allowed) {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+
+  TabSpecificContentSettings* content_settings =
+      TabSpecificContentSettings::Get(id.render_process_id(),
+                                      id.render_view_id());
+  if (content_settings) {
+    if (allowed)
+      content_settings->OnMIDISysExAccessed(requesting_frame);
+    else
+      content_settings->OnMIDISysExAccessBlocked(requesting_frame);
+  }
+
+  callback.Run(allowed);
+}
+
+PermissionQueueController*
+    ChromeMIDIPermissionContext::QueueController() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  DCHECK(!shutting_down_);
+  if (!permission_queue_controller_)
+    permission_queue_controller_.reset(CreateQueueController());
+  return permission_queue_controller_.get();
+}
+
+PermissionQueueController*
+    ChromeMIDIPermissionContext::CreateQueueController() {
+  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  return new PermissionQueueController(profile(),
+                                       CONTENT_SETTINGS_TYPE_MIDI_SYSEX);
+}