DevTools protocol interception, blocking & modification of requests

content/browser/devtools/devtools_url_request_interceptor.h

+// Copyright 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 CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_URL_REQUEST_INTERCEPTOR_H_
+#define CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_URL_REQUEST_INTERCEPTOR_H_
+
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "content/browser/devtools/protocol/network.h"
+#include "net/url_request/url_request_interceptor.h"
+
+namespace content {
+
+// An interceptor that creates DevToolsURLInterceptorRequestJobs for requests
+// from pages where interception has been enabled via
+// Network.enableFetchInterception.
+class DevToolsURLRequestInterceptor : public net::URLRequestInterceptor {
+ public:
+  DevToolsURLRequestInterceptor();
+  ~DevToolsURLRequestInterceptor() override;
+
+  net::URLRequestJob* MaybeInterceptRequest(
+      net::URLRequest* request,
+      net::NetworkDelegate* network_delegate) const override;
+
+  net::URLRequestJob* MaybeInterceptRedirect(
+      net::URLRequest* request,
+      net::NetworkDelegate* network_delegate,
+      const GURL& location) const override;
+
+  net::URLRequestJob* MaybeInterceptResponse(
+      net::URLRequest* request,
+      net::NetworkDelegate* network_delegate) const override;
+
+  // Ideally this inner class wouldn't exist but the interface methods are
+  // const :(
+  class State {
+   public:
+    State();
+    ~State();
+
+    void RegisterSubRequest(const net::URLRequest* request);
+    void UnregisterSubRequest(const net::URLRequest* request);
+
+    // Returns true if |request| as a currently registered request.
+    bool IsSubRequest(const net::URLRequest* request) const;
+
+    // To make the user's life easier we make sure requests in a redirect chain
+    // all have the same id.
+    void ExpectRequestAfterRedirect(const net::URLRequest* request,
+                                    std::string id);
+
+    std::string GetNewId();
+    std::string GetRedirectChainParentId(const net::URLRequest* request);
+
+    base::WeakPtr<State> GetWeakPtr() { return weak_ptr_factory_.GetWeakPtr(); }
+
+   private:
+    std::unordered_set<const net::URLRequest*> sub_requests_;
+    std::unordered_map<const net::URLRequest*, std::string> expected_redirects_;
+    size_t next_id_;
+    base::WeakPtrFactory<State> weak_ptr_factory_;
+  };
+
+ private:
+  std::unique_ptr<State> state_;
+
+  DISALLOW_COPY_AND_ASSIGN(DevToolsURLRequestInterceptor);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_URL_REQUEST_INTERCEPTOR_H_