[Android WebView] AwContentsClient.shouldCreate window callback part 2.

android_webview/browser/renderer_host/aw_resource_dispatcher_host_delegate.cc

 // Copyright (c) 2012 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 "android_webview/browser/renderer_host/aw_resource_dispatcher_host_delegate.h"
 
 #include "android_webview/browser/aw_login_delegate.h"
 #include "android_webview/browser/aw_contents_io_thread_client.h"
 #include "android_webview/common/url_constants.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "content/components/navigation_interception/intercept_navigation_delegate.h"
+#include "content/public/browser/browser_thread.h"
 #include "content/public/browser/resource_controller.h"
 #include "content/public/browser/resource_dispatcher_host.h"
 #include "content/public/browser/resource_dispatcher_host_login_delegate.h"
 #include "content/public/browser/resource_throttle.h"
 #include "content/public/common/url_constants.h"
 #include "net/base/load_flags.h"
 #include "net/url_request/url_request.h"
 
 using content::InterceptNavigationDelegate;
 
 namespace {
 
 using android_webview::AwContentsIoThreadClient;
+using content::BrowserThread;
 
 base::LazyInstance<android_webview::AwResourceDispatcherHostDelegate>
     g_webview_resource_dispatcher_host_delegate = LAZY_INSTANCE_INITIALIZER;
 
 void SetOnlyAllowLoadFromCache(
     net::URLRequest* request) {
   int load_flags = request->load_flags();
   load_flags &= ~(net::LOAD_BYPASS_CACHE &
                   net::LOAD_VALIDATE_CACHE &
                   net::LOAD_PREFERRING_CACHE);
@@ skipping 16 matching lines @@
     return AwContentsIoThreadClient::FromID(child_id_, route_id_);
   }
 
  private:
   int child_id_;
   int route_id_;
   net::URLRequest* request_;
 };
 
 void MaybeCancelResourceThrottle::WillStartRequest(bool* defer) {
-  // If there is no IO thread client set at this point, use a
-  // restrictive policy. This can happen for blocked popup
-  // windows for example.
-  // TODO(benm): Revert this to a DCHECK when the we support
-  // pop up windows being created in the WebView, as at that
-  // time we should always have an IoThreadClient at this
-  // point (i.e., the one associated with the new popup).
-  if (!GetIoThreadClient()) {
-    controller()->CancelWithError(net::ERR_ACCESS_DENIED);
-    return;
-  }
+  DCHECK(GetIoThreadClient());
 
   // Part of implementation of WebSettings.allowContentAccess.
   if (request_->url().SchemeIs(android_webview::kContentScheme) &&
       GetIoThreadClient()->ShouldBlockContentUrls()) {
     controller()->CancelWithError(net::ERR_ACCESS_DENIED);
     return;
   }
 
   // Part of implementation of WebSettings.allowFileAccess.
   if (request_->url().SchemeIsFile() &&
@@ skipping 10 matching lines @@
 
   if (GetIoThreadClient()->ShouldBlockNetworkLoads()) {
     if (request_->url().SchemeIs(chrome::kFtpScheme)) {
       controller()->CancelWithError(net::ERR_ACCESS_DENIED);
       return;
     }
     SetOnlyAllowLoadFromCache(request_);
   }
 }
 
+class DeferUntilIoThreadClientReadyThrottle
+    : public content::ResourceThrottle,
+      public AwContentsIoThreadClient::ReadyObserver {
+ public:
+  DeferUntilIoThreadClientReadyThrottle(int child_id, int route_id)
+    : child_id_(child_id),
+      route_id_(route_id),
+      resumed_(false) {
+  }
+
+  virtual ~DeferUntilIoThreadClientReadyThrottle() {
+    AwContentsIoThreadClient::RemoveReadyObserver(this);
+  }
+
+  virtual void WillStartRequest(bool* defer) OVERRIDE {
+    MaybeDeferRequest(defer);
+  }
+
+  virtual void WillRedirectRequest(const GURL& new_url, bool* defer) OVERRIDE {
+    MaybeDeferRequest(defer);
+  }
+
+  void MaybeDeferRequest(bool* defer) {
+    if (!AwContentsIoThreadClient::FromID(child_id_, route_id_)) {
+      *defer = true;
+      AwContentsIoThreadClient::AddReadyObserver(this);
+    } else {
+      *defer = false;
+    }
+  }
+
+  void OnIoThreadClientReady(int new_child_id, int new_route_id) {
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+    // If we've now got the IoThreadClient that we were waiting on,
+    // resume the request.
+    if (!resumed_ && new_child_id == child_id_ && new_route_id == route_id_) {

[mkosiba (inactive), 2012/11/16 12:28:32]

it seems like this is a good place to run all of the logic from
MaybeCancelResourceThrottle::WillStartRequest.

I don't have a good name for the resulting class though.

[benm (inactive), 2012/11/16 12:36:31]

IoThreadClientThrottle maybe?

With a class comment saying something along the lines of 
"defers until the IO client is ready, then will potentially cancel the request
depending on the result of client callbacks"?

+      controller()->Resume();
+      resumed_ = true;
+    }
+  }
+
+private:
+  int child_id_;
+  int route_id_;
+  bool resumed_;
+};
+
 }  // namespace
 
 namespace android_webview {
 
 // static
 void AwResourceDispatcherHostDelegate::ResourceDispatcherHostCreated() {
   content::ResourceDispatcherHost::Get()->SetDelegate(
       &g_webview_resource_dispatcher_host_delegate.Get());
 }
 
 AwResourceDispatcherHostDelegate::AwResourceDispatcherHostDelegate()
     : content::ResourceDispatcherHostDelegate() {
 }
 
 AwResourceDispatcherHostDelegate::~AwResourceDispatcherHostDelegate() {
 }
 
 void AwResourceDispatcherHostDelegate::RequestBeginning(
     net::URLRequest* request,
     content::ResourceContext* resource_context,
     appcache::AppCacheService* appcache_service,
     ResourceType::Type resource_type,
     int child_id,
     int route_id,
     bool is_continuation_of_transferred_request,
     ScopedVector<content::ResourceThrottle>* throttles) {
 
+  // If there's no IoClient yet, then we need to defer until there is one.
+  if (!AwContentsIoThreadClient::FromID(child_id, route_id)) {
+    throttles->push_back(new DeferUntilIoThreadClientReadyThrottle(
+        child_id, route_id));
+  }
+
   throttles->push_back(new MaybeCancelResourceThrottle(
       child_id, route_id, request));
 
   if (resource_type == ResourceType::MAIN_FRAME) {
     throttles->push_back(InterceptNavigationDelegate::CreateThrottleFor(
         request));
   }
 }
 
 bool AwResourceDispatcherHostDelegate::AcceptAuthRequest(
@@ skipping 12 matching lines @@
 bool AwResourceDispatcherHostDelegate::HandleExternalProtocol(const GURL& url,
                                                               int child_id,
                                                               int route_id) {
   // The AwURLRequestJobFactory implementation should ensure this method never
   // gets called.
   NOTREACHED();
   return false;
 }
 
 }