Adding Navigation Throttles to DevTools

content/browser/devtools/page_navigation_throttle.cc

Index: content/browser/devtools/page_navigation_throttle.cc
diff --git a/content/browser/devtools/page_navigation_throttle.cc b/content/browser/devtools/page_navigation_throttle.cc
new file mode 100644
index 0000000000000000000000000000000000000000..728e08235ede1b2777988b2d2a08af52954cec8d
--- /dev/null
+++ b/content/browser/devtools/page_navigation_throttle.cc
@@ -0,0 +1,73 @@
+// Copyright 2016 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 "content/browser/devtools/page_navigation_throttle.h"
+
+#include "base/strings/stringprintf.h"
+#include "content/browser/devtools/protocol/page_handler.h"
+#include "content/public/browser/navigation_handle.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/web_contents.h"
+
+namespace content {
+namespace devtools {
+
+PageNavigationThrottle::PageNavigationThrottle(
+    base::WeakPtr<page::PageHandler> page_handler,
+    int navigation_id,
+    content::NavigationHandle* navigation_handle)
+    : content::NavigationThrottle(navigation_handle),
+      navigation_id_(navigation_id),
+      page_handler_(page_handler),
+      response_pending_(false) {}
+
+PageNavigationThrottle::~PageNavigationThrottle() {
+  if (page_handler_)
+    page_handler_->OnPageNavigationThrottleDisposed(navigation_id_);
+}
+
+NavigationThrottle::ThrottleCheckResult
+PageNavigationThrottle::WillStartRequest() {
+  if (!page_handler_)
+    return ThrottleCheckResult::PROCEED;
+  response_pending_ = true;

[nasko, 2016/07/13 22:37:34]

nit: This boolean seems to indicate that the navigation is deferred. Can we just
name it to be closer to its meaning?

[alex clarke (OOO till 29th), 2016/07/14 16:06:04]

Done.

+  page_handler_->NavigationRequested(this);
+  return ThrottleCheckResult::DEFER;
+}
+
+NavigationThrottle::ThrottleCheckResult
+PageNavigationThrottle::WillRedirectRequest() {
+  if (!page_handler_)
+    return ThrottleCheckResult::PROCEED;
+  response_pending_ = true;
+  page_handler_->NavigationRequested(this);
+  return ThrottleCheckResult::DEFER;
+}
+
+void PageNavigationThrottle::AlwaysProceed() {
+  // Makes WillStartRequest and WillRedirectRequest always return
+  // ThrottleCheckResult::PROCEED.
+  page_handler_.reset();
+
+  if (response_pending_)
+    Resume();
+}
+
+void PageNavigationThrottle::Resume() {
+  if (!response_pending_)
+    return;
+  navigation_handle()->Resume();
+  response_pending_ = false;
+}
+
+void PageNavigationThrottle::CancelDeferredNavigation(
+    NavigationThrottle::ThrottleCheckResult result) {
+  if (!response_pending_)
+    return;
+  navigation_handle()->CancelDeferredNavigation(result);
+  response_pending_ = false;
+}
+
+}  // namespace devtools
+}  // namespace content