[ABANDONED] [WIP] Refactor SafeBrowsingResourceThrottle in preparation for WebSocket

components/safe_browsing/resource_throttle.h

Index: components/safe_browsing/resource_throttle.h
diff --git a/components/safe_browsing/resource_throttle.h b/components/safe_browsing/resource_throttle.h
new file mode 100644
index 0000000000000000000000000000000000000000..7e32c521fb9600fd3d2e8e8cc2dcb263d47507cd
--- /dev/null
+++ b/components/safe_browsing/resource_throttle.h
@@ -0,0 +1,101 @@
+// Copyright (c) 2017 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.
+
+#ifndef COMPONENTS_SAFE_BROWSING_RESOURCE_THROTTLE_H_
+#define COMPONENTS_SAFE_BROWSING_RESOURCE_THROTTLE_H_
+
+#include <memory>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "components/safe_browsing/request_checker.h"
+#include "content/public/browser/resource_throttle.h"
+#include "content/public/common/resource_type.h"
+
+namespace net {
+class URLRequest;
+}
+
+namespace security_interstitials {
+struct UnsafeResource;
+}
+
+namespace safe_browsing {
+
+class BaseUIManager;
+class SafeBrowsingDatabaseManager;
+
+// ResourceThrottle checks that URLs are "safe" before
+// navigating to them. To be considered "safe", a URL must not appear in the
+// malware/phishing blacklists (see SafeBrowsingService for details).
+//
+// Note that the safe browsing check takes at most kCheckUrlTimeoutMs
+// milliseconds. If it takes longer than this, then the system defaults to
+// treating the URL as safe.
+//
+// If the URL is classified as dangerous, a warning page is thrown up and
+// the request remains suspended.  If the user clicks "proceed" on warning
+// page, we resume the request.
+//
+// Note: The ResourceThrottle interface is called in this order:
+// WillStartRequest once, WillRedirectRequest zero or more times, and then
+// WillProcessReponse once.
+class ResourceThrottle final : public content::ResourceThrottle,
+                               public RequestChecker::Delegate {
+ public:
+  class Delegate {
+   public:
+    Delegate() {}
+    virtual ~Delegate() {}
+    virtual void MaybeDestroyPrerenderContents(
+        const net::URLRequest* request) = 0;
+    virtual void StartDisplayingBlockingPage(
+        const security_interstitials::UnsafeResource& resource,
+        scoped_refptr<BaseUIManager> ui_manager,
+        base::OnceClosure cancel_on_io_thread) = 0;
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Delegate);
+  };
+
+  ResourceThrottle(const net::URLRequest* request,
+                   content::ResourceType resource_type,
+                   scoped_refptr<SafeBrowsingDatabaseManager> database_manager,
+                   scoped_refptr<BaseUIManager> ui_manager,
+                   std::unique_ptr<Delegate> delegate);
+
+  ~ResourceThrottle() final;
+
+  // content::ResourceThrottle implementation (called on IO thread):
+  void WillStartRequest(bool* defer) final;
+  void WillRedirectRequest(const net::RedirectInfo& redirect_info,
+                           bool* defer) final;
+  void WillProcessResponse(bool* defer) final;
+  bool MustProcessResponseBeforeReadingBody() final;
+
+  const char* GetNameForLogging() const final;
+
+  // RequestChecker::Delegate implementation.
+  void MaybeDestroyPrerenderContents(const net::URLRequest* request) final;
+  RequestChecker::Delegate::WebContentsGetter GetWebContentsGetterForRequest(
+      const net::URLRequest* request) const final;
+  void StartDisplayingBlockingPage(
+      const security_interstitials::UnsafeResource& resource,
+      scoped_refptr<BaseUIManager> ui_manager) final;
+  void CancelResourceLoad() final;
+  void ResumeResourceRequest() final;
+
+ private:
+  RequestChecker request_checker_;
+  std::unique_ptr<Delegate> delegate_;
+  base::WeakPtrFactory<ResourceThrottle> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ResourceThrottle);
+};
+
+}  // namespace safe_browsing
+
+#endif  // COMPONENTS_SAFE_BROWSING_RESOURCE_THROTTLE_H_