Implementation of the "Redirect URLs to Packaged Apps" feature.

chrome/browser/extensions/platform_app_redirector.cc

Index: chrome/browser/extensions/platform_app_redirector.cc
diff --git a/chrome/browser/extensions/platform_app_redirector.cc b/chrome/browser/extensions/platform_app_redirector.cc
new file mode 100644
index 0000000000000000000000000000000000000000..769c50c5d86efe57cb4f79a5ce36beb3567019bb
--- /dev/null
+++ b/chrome/browser/extensions/platform_app_redirector.cc
@@ -0,0 +1,78 @@
+// Copyright (c) 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/extensions/platform_app_redirector.h"
+
+#include "base/logging.h"
+#include "chrome/browser/extensions/api/app_runtime/app_runtime_api.h"
+#include "chrome/browser/extensions/extension_service.h"
+#include "chrome/browser/extensions/extension_system.h"
+#include "chrome/browser/extensions/platform_app_launcher.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/extensions/api/url_handlers/url_handlers_parser.h"
+#include "chrome/common/extensions/extension_set.h"
+#include "content/public/browser/notification_details.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_source.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/url_handling_notifications.h"
+#include "googleurl/src/gurl.h"
+
+namespace extensions {
+
+PlatformAppRedirector::PlatformAppRedirector(Profile* profile)
+    : profile_(profile),
+      extensions_(extensions::ExtensionSystem::Get(profile)->
+                    extension_service()->extensions()) {
+  registrar_.Add(this, content::NOTIFICATION_HANDLE_URL_IN_BROWSER,
+                 content::NotificationService::AllBrowserContextsAndSources());

[not at google - send to devlin, 2013/08/29 17:35:56]

All profiles? really? If you register this only for |profile| then you don't
need that check below.

(but keep incognito mode in mind)

[sergeygs, 2013/08/30 00:39:44]

Done. Great catch.

+}
+
+bool PlatformAppRedirector::MaybeLaunchPlatformAppWithUrl(
+    const GURL& url,
+    const GURL& referrer_url) const {
+  for (ExtensionSet::const_iterator it = extensions_->begin();
+       it != extensions_->end(); ++it) {
+    const extensions::UrlHandlerInfo* handler =
+        UrlHandlers::FindMatchingUrlHandler(*it, url);
+    if (handler) {
+      extensions::LaunchPlatformAppWithUrl(
+          profile_, *it, handler->id, url, referrer_url);
+      return true;
+    }
+  }
+  return false;
+}
+
+void PlatformAppRedirector::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  switch (type) {
+    case content::NOTIFICATION_HANDLE_URL_IN_BROWSER: {

[not at google - send to devlin, 2013/08/29 17:35:56]

It would be really nice if you could not use a notification for this but instead
an Observer interface of some sort.

[sergeygs, 2013/08/30 00:39:44]

It seemed really hard to connect the two communicating entities together with an
Observer at the time (now less so, but still). I've added a TODO to follow-up on
this. This currently works fine, and the only difficulty is that it's harder to
find who talks to who, and there is that blind type-casting on the receiving
end.

[not at google - send to devlin, 2013/08/30 17:07:58]

So this class can't implement URL filter or something?

(I have no idea how this stuff is supposed to work)

[sergeygs, 2013/09/02 07:36:21]

This completely goes away in the 2nd round of smaller CLs (will check in very
soon), and indeed, the entire notifications and BrowserMessageFilter business
disappears, after talking to jam@ and implementing a routed IPC instead of a
control one (which indirectly necessitated all of the above).

+      // Limit app launching to the originating profile only.
+      if (profile_ !=
+          Profile::FromBrowserContext(
+              content::Source<content::RenderProcessHost>(source).ptr()->
+                GetBrowserContext())) {
+        break;
+      }
+      // Attempt to launch the app.
+      content::ForwardUrlToBrowserDetails* launch =
+          content::Details<content::ForwardUrlToBrowserDetails>(details).ptr();
+      const bool launched =
+          MaybeLaunchPlatformAppWithUrl(launch->url, launch->referrer_url);
+      // The issuer of this notification must that a handling app
+      // exists before sending this notification.
+      DCHECK(launched);
+      break;
+    }
+
+    default:
+      NOTREACHED() << "Unexpected notification type.";

[not at google - send to devlin, 2013/08/29 17:35:56]

just DCHECK(type == content::NOTIFICATION_HANDLE_URL_IN_BROWSER) at the start
and not worry about the switch at all.

[sergeygs, 2013/08/30 00:39:44]

The way it is now is a common pattern around the code, and it's more easily
extendable (if some other notification is to be handled here in future).

+  }
+}
+
+}  // namespace extensions