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* Copyright 2012 Google Inc.
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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* http://www.apache.org/licenses/LICENSE-2.0
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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// Author: mmohabey@google.com (Megha Mohabey)
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#ifndef NET_INSTAWEB_REWRITER_PUBLIC_DETERMINISTIC_JS_FILTER_H_
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#define NET_INSTAWEB_REWRITER_PUBLIC_DETERMINISTIC_JS_FILTER_H_
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#include "net/instaweb/htmlparse/public/empty_html_filter.h"
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#include "net/instaweb/util/public/basictypes.h"
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namespace net_instaweb {
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// Injects javascript at the beginning of the head tag to make it deterministic.
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// The JS redefines functions like Math.random and Date. This filter is useful
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// for testing and measurement but does not provide any latency gains. A head
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// element is added if it is not already present in the html.
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class DeterministicJsFilter : public EmptyHtmlFilter {
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explicit DeterministicJsFilter(RewriteDriver* driver);
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virtual ~DeterministicJsFilter();
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virtual void StartDocument();
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virtual void StartElement(HtmlElement* element);
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virtual const char* Name() const { return "DeterministicJs"; }
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RewriteDriver* driver_;
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DISALLOW_COPY_AND_ASSIGN(DeterministicJsFilter);
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} // namespace net_instaweb
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#endif // NET_INSTAWEB_REWRITER_PUBLIC_DETERMINISTIC_JS_FILTER_H_