| /* |
| * Copyright 2010 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| // Author: jmarantz@google.com (Joshua Marantz) |
| |
| #ifndef NET_INSTAWEB_REWRITER_PUBLIC_CACHE_EXTENDER_H_ |
| #define NET_INSTAWEB_REWRITER_PUBLIC_CACHE_EXTENDER_H_ |
| |
| #include "net/instaweb/rewriter/public/resource.h" // for ResourcePtr |
| #include "net/instaweb/rewriter/public/resource_slot.h" |
| #include "net/instaweb/rewriter/public/rewrite_filter.h" |
| #include "net/instaweb/rewriter/public/rewrite_options.h" |
| #include "net/instaweb/rewriter/public/rewrite_result.h" |
| #include "net/instaweb/rewriter/public/server_context.h" |
| #include "pagespeed/kernel/base/basictypes.h" |
| #include "pagespeed/kernel/base/string_util.h" |
| |
| namespace net_instaweb { |
| |
| class CachedResult; |
| class HtmlElement; |
| class ResponseHeaders; |
| class RewriteContext; |
| class RewriteDriver; |
| class Statistics; |
| class Variable; |
| |
| // Rewrites resources without changing their content -- just their |
| // URLs and headers. The original intent of this filter was limited |
| // to cache extension. However, its scope has been expanded to include |
| // domain sharding and moving static resources to cookieless domains or |
| // CDNs. |
| // |
| // TODO(jmarantz): rename this class to something more generic, like |
| // RenameUrlFilter or ProxyUrlFilter. |
| class CacheExtender : public RewriteFilter { |
| public: |
| static const char kCacheExtensions[]; |
| static const char kNotCacheable[]; |
| |
| explicit CacheExtender(RewriteDriver* driver); |
| virtual ~CacheExtender(); |
| |
| static void InitStats(Statistics* statistics); |
| |
| virtual void StartDocumentImpl() {} |
| virtual void StartElementImpl(HtmlElement* element); |
| virtual void EndElementImpl(HtmlElement* element) {} |
| |
| virtual const char* Name() const { return "CacheExtender"; } |
| virtual const char* id() const { return RewriteOptions::kCacheExtenderId; } |
| |
| // Creates a nested rewrite for given parent and slot, and returns it. |
| // The result is not registered with the parent. |
| RewriteContext* MakeNestedContext(RewriteContext* parent, |
| const ResourceSlotPtr& slot); |
| |
| protected: |
| virtual bool ComputeOnTheFly() const; |
| virtual RewriteContext* MakeRewriteContext(); |
| |
| private: |
| class Context; |
| friend class Context; |
| |
| RewriteResult RewriteLoadedResource(const ResourcePtr& input_resource, |
| const OutputResourcePtr& output_resource, |
| CachedResult* result); |
| |
| bool ShouldRewriteResource( |
| const ResponseHeaders* headers, int64 now_ms, |
| const ResourcePtr& input_resource, const StringPiece& url, |
| CachedResult* result) const; |
| |
| Variable* extension_count_; |
| Variable* not_cacheable_count_; |
| |
| DISALLOW_COPY_AND_ASSIGN(CacheExtender); |
| }; |
| |
| } // namespace net_instaweb |
| |
| #endif // NET_INSTAWEB_REWRITER_PUBLIC_CACHE_EXTENDER_H_ |