| // Copyright 2015 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_LOADER_ASYNC_REVALIDATION_MANAGER_H_ |
| #define CONTENT_BROWSER_LOADER_ASYNC_REVALIDATION_MANAGER_H_ |
| |
| #include <map> |
| #include <string> |
| |
| #include "base/macros.h" |
| #include "base/memory/scoped_ptr.h" |
| |
| class GURL; |
| struct ResourceHostMsg_Request; |
| |
| namespace net { |
| class URLRequest; |
| class HttpCache; |
| } |
| |
| namespace content { |
| |
| class AsyncRevalidationDriver; |
| class ResourceContext; |
| class ResourceScheduler; |
| |
| // One instance of this class manages all active AsyncRevalidationDriver objects |
| // for all profiles. It is created by and owned by |
| // ResourceDispatcherHostImpl. It also implements the creation of a new |
| // net::URLRequest and AsyncRevalidationDriver from an existing net::URLRequest |
| // that has had the stale-while-revalidate algorithm applied to it. |
| class AsyncRevalidationManager { |
| public: |
| AsyncRevalidationManager(); |
| ~AsyncRevalidationManager(); |
| |
| // Starts an async revalidation by copying |for_request|. |scheduler| must |
| // remain valid until this object is destroyed. |
| void BeginAsyncRevalidation(const net::URLRequest& for_request, |
| ResourceScheduler* scheduler); |
| |
| // Cancel all pending async revalidations that use ResourceContext. |
| void CancelAsyncRevalidationsForResourceContext( |
| ResourceContext* resource_context); |
| |
| static bool QualifiesForAsyncRevalidation( |
| const ResourceHostMsg_Request& request); |
| |
| private: |
| // The key of the map of pending async revalidations. This key has a distinct |
| // value for every in-progress async revalidation. It is used to avoid |
| // duplicate async revalidations, and also to cancel affected async |
| // revalidations when a ResourceContext is removed. |
| // |
| // Request headers are intentionally not included in the key for simplicity, |
| // as they usually don't affect caching. |
| // |
| // TODO(ricea): Behave correctly in cases where the request headers do make a |
| // difference. crbug.com/567721 |
| struct AsyncRevalidationKey { |
| AsyncRevalidationKey(const ResourceContext* resource_context, |
| const net::HttpCache* http_cache, |
| const GURL& url); |
| |
| // Create a prefix key that is used to match all of the |
| // AsyncRevalidationDrivers using |resource_context| in the map. |
| explicit AsyncRevalidationKey(const ResourceContext* resource_context); |
| |
| // The key for a map needs to be copyable. |
| AsyncRevalidationKey(const AsyncRevalidationKey& rhs) = default; |
| ~AsyncRevalidationKey(); |
| |
| // No operator= is generated because the struct members are immutable. |
| |
| // |resource_context| and |http_cache| are never dereferenced; they are only |
| // compared to other values. |
| const ResourceContext* const resource_context; |
| |
| // There are multiple independent HttpCache objects per ResourceContext. |
| const net::HttpCache* const http_cache; |
| |
| // Derived from the url via net::HttpUtil::SpecForRequest(). |
| const std::string url_key; |
| |
| struct LessThan { |
| bool operator()(const AsyncRevalidationKey& lhs, |
| const AsyncRevalidationKey& rhs) const; |
| }; |
| }; |
| |
| using AsyncRevalidationMap = std::map<AsyncRevalidationKey, |
| scoped_ptr<AsyncRevalidationDriver>, |
| AsyncRevalidationKey::LessThan>; |
| |
| void OnAsyncRevalidationComplete(AsyncRevalidationMap::iterator it); |
| |
| // Map of AsyncRevalidationDriver instances that are currently in-flight: |
| // either waiting to be scheduled or active on the network. |
| AsyncRevalidationMap in_progress_; |
| |
| DISALLOW_COPY_AND_ASSIGN(AsyncRevalidationManager); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_BROWSER_LOADER_ASYNC_REVALIDATION_MANAGER_H_ |