| // 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. |
| |
| #ifndef CONTENT_PUBLIC_BROWSER_RESOURCE_THROTTLE_H_ |
| #define CONTENT_PUBLIC_BROWSER_RESOURCE_THROTTLE_H_ |
| |
| #include "content/common/content_export.h" |
| |
| namespace net { |
| struct RedirectInfo; |
| } |
| |
| namespace content { |
| |
| class AsyncRevalidationDriver; |
| class ResourceController; |
| class ThrottlingResourceHandler; |
| |
| // A ResourceThrottle gets notified at various points during the process of |
| // loading a resource. At each stage, it has the opportunity to defer the |
| // resource load. The ResourceController interface may be used to resume a |
| // deferred resource load, or it may be used to cancel a resource load at any |
| // time. |
| class CONTENT_EXPORT ResourceThrottle { |
| public: |
| // An interface to get notified when the throttle implementation considers |
| // it's ready to resume the deferred resource load. The throttle |
| // implementation may also tell the delegate to cancel the resource loading. |
| class CONTENT_EXPORT Delegate { |
| public: |
| // Cancels the resource load. |
| virtual void Cancel() = 0; |
| // Cancels the resource load with the specified error code. |
| virtual void CancelWithError(int error_code) = 0; |
| // Tells the delegate to resume the deferred resource load. |
| virtual void Resume() = 0; |
| |
| protected: |
| virtual ~Delegate() {} |
| }; |
| |
| virtual ~ResourceThrottle() {} |
| |
| // Called before the resource request is started. |
| virtual void WillStartRequest(bool* defer) {} |
| |
| // Called when the request was redirected. |redirect_info| contains the |
| // redirect responses's HTTP status code and some information about the new |
| // request that will be sent if the redirect is followed, including the new |
| // URL and new method. |
| virtual void WillRedirectRequest(const net::RedirectInfo& redirect_info, |
| bool* defer) {} |
| |
| // Called when the response headers and meta data are available. |
| virtual void WillProcessResponse(bool* defer) {} |
| |
| // Returns the name of the throttle, as a UTF-8 C-string, for logging |
| // purposes. nullptr is not allowed. Caller does *not* take ownership of the |
| // returned string. |
| virtual const char* GetNameForLogging() = 0; |
| |
| // Whether this ResourceThrottle needs to execute WillProcessResponse before |
| // any part of the response body is read. Normally this is false. This should |
| // be set to true if the ResourceThrottle wants to ensure that no part of the |
| // response body will be cached if the request is canceled in |
| // WillProcessResponse. |
| virtual bool MustProcessResponseBeforeReadingBody(); |
| |
| void set_delegate_for_testing(Delegate* delegate) { delegate_ = delegate; } |
| |
| protected: |
| ResourceThrottle() : delegate_(nullptr) {} |
| |
| // Helper methods for subclasses. When these methods are called, methods with |
| // the same name on |delegate_| are called. |
| void Cancel(); |
| void CancelWithError(int error_code); |
| void Resume(); |
| |
| private: |
| friend class AsyncRevalidationDriver; |
| friend class ThrottlingResourceHandler; |
| |
| void set_delegate(Delegate* delegate) { delegate_ = delegate; } |
| |
| Delegate* delegate_; |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_PUBLIC_BROWSER_RESOURCE_THROTTLE_H_ |