添加<setBuffering enabled="true|false" /> valve，可以在pipeline中开关buffering…

…，以简化screen代码。

CHANGES_SINCE_3.1.0.txt

@@ -68,3 +68,4 @@
     有些测试代码需要实现ServletContext接口，但是由于servlet3和2版本对于该接口的API不同，导致无法用一套代码同时兼容servlet3和2。用动态生成类工具就可以解决这个问题。
 * 改进request context服务，使之在async模式被启动时，不会提交response。当async线程重新取得控制时，可以重新取得原来的request context。
 * 改进<renderTemplate> valve，当buffering关闭时，只不过不显示layout，而不会报错。
+* 添加<setBuffering enabled="true|false" /> valve，可以在pipeline中开关buffering，以简化screen代码。

webx/turbine/src/main/java/com/alibaba/citrus/turbine/pipeline/valve/SetBufferingValve.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2002-2012 Alibaba Group Holding Limited.
+ * All rights reserved.
+ *
+ * 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.
+ */
+
+package com.alibaba.citrus.turbine.pipeline.valve;
+
+import static com.alibaba.citrus.springext.util.SpringExtUtil.*;
+
+import com.alibaba.citrus.service.pipeline.PipelineContext;
+import com.alibaba.citrus.service.pipeline.support.AbstractValve;
+import com.alibaba.citrus.service.pipeline.support.AbstractValveDefinitionParser;
+import com.alibaba.citrus.service.requestcontext.buffered.BufferedRequestContext;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.support.BeanDefinitionBuilder;
+import org.springframework.beans.factory.xml.ParserContext;
+import org.w3c.dom.Element;
+
+/**
+ * 开关buffering。
+ *
+ * @author Michael Zhou
+ */
+public class SetBufferingValve extends AbstractValve {
+    private Logger log = LoggerFactory.getLogger(getClass());
+    private boolean enabled;
+
+    @Autowired
+    private BufferedRequestContext brc;
+
+    public void setEnabled(boolean enabled) {
+        this.enabled = enabled;
+    }
+
+    @Override
+    public void invoke(PipelineContext pipelineContext) throws Exception {
+        try {
+            brc.setBuffering(enabled);
+        } catch (IllegalStateException e) {
+            log.warn("Unable to setBuffering({}): {}", enabled, e.getMessage());
+        }
+    }
+
+    public static class DefinitionParser extends AbstractValveDefinitionParser<SetBufferingValve> {
+        @Override
+        protected void doParse(Element element, ParserContext parserContext, BeanDefinitionBuilder builder) {
+            attributesToProperties(element, builder, "enabled");
+        }
+    }
+}

webx/turbine/src/main/resources/META-INF/services-pipeline-valves.bean-definition-parsers

@@ -8,6 +8,7 @@ analyzeURL=com.alibaba.citrus.turbine.pipeline.valve.AnalyzeURLValve$DefinitionP
 checkCsrfToken=com.alibaba.citrus.turbine.pipeline.valve.CheckCsrfTokenValve$DefinitionParser
 getResource=com.alibaba.citrus.turbine.pipeline.valve.GetResourceValve$DefinitionParser
 
+setBuffering=com.alibaba.citrus.turbine.pipeline.valve.SetBufferingValve$DefinitionParser
 performAction=com.alibaba.citrus.turbine.pipeline.valve.PerformActionValve$DefinitionParser
 performTemplateScreen=com.alibaba.citrus.turbine.pipeline.valve.PerformTemplateScreenValve$DefinitionParser
 performScreen=com.alibaba.citrus.turbine.pipeline.valve.PerformScreenValve$DefinitionParser

webx/turbine/src/main/resources/META-INF/services/pipeline/valves/setBuffering.xsd

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
+            xmlns:springext="http://www.alibaba.com/schema/springext/base" elementFormDefault="qualified">
+
+    <xsd:import namespace="http://www.springframework.org/schema/beans"
+                schemaLocation="http://localhost:8080/schema/www.springframework.org/schema/beans/spring-beans.xsd" />
+
+    <xsd:import namespace="http://www.alibaba.com/schema/springext/base"
+                schemaLocation="http://localhost:8080/schema/www.alibaba.com/schema/springext/springext-base.xsd" />
+
+    <xsd:element name="setBuffering" type="SetBufferingValveType">
+        <xsd:annotation>
+            <xsd:documentation><![CDATA[
+    开关buffering。
+            ]]></xsd:documentation>
+        </xsd:annotation>
+    </xsd:element>
+
+    <xsd:complexType name="SetBufferingValveType">
+        <xsd:attribute name="enabled" type="springext:booleanOrPlaceholder" default="true" />
+    </xsd:complexType>
+
+</xsd:schema>

webx/turbine/src/test/config/WEB-INF/webx-app1.xml

@@ -34,6 +34,18 @@
         <valves:valve class="com.alibaba.citrus.turbine.pipeline.valve.CheckCsrfTokenValveTests$CheckCsrfManually" />
     </services:pipeline>
 
+    <services:pipeline id="setBuffering_default">
+        <valves:setBuffering />
+    </services:pipeline>
+
+    <services:pipeline id="setBuffering_enabled">
+        <valves:setBuffering enabled="true" />
+    </services:pipeline>
+
+    <services:pipeline id="setBuffering_disabled">
+        <valves:setBuffering enabled="false" />
+    </services:pipeline>
+
     <services:pipeline id="performActionValveTests">
         <valves:analyzeURL actionParam="action" />
         <valves:performAction />

webx/turbine/src/test/java/com/alibaba/citrus/turbine/pipeline/valve/SetBufferingValveTests.java

@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2002-2012 Alibaba Group Holding Limited.
+ * All rights reserved.
+ *
+ * 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.
+ */
+
+package com.alibaba.citrus.turbine.pipeline.valve;
+
+import static com.alibaba.citrus.service.requestcontext.util.RequestContextUtil.*;
+import static org.junit.Assert.*;
+
+import com.alibaba.citrus.service.pipeline.impl.PipelineImpl;
+import com.alibaba.citrus.service.requestcontext.buffered.BufferedRequestContext;
+import org.junit.Test;
+
+public class SetBufferingValveTests extends AbstractValveTests {
+    private BufferedRequestContext brc;
+
+    private void initPipeline(String id) {
+        pipeline = (PipelineImpl) factory.getBean(id);
+        assertNotNull(pipeline);
+    }
+
+    @Test
+    public void setBuffering_default() throws Exception {
+        assertBufferingEnabled("setBuffering_default");
+    }
+
+    @Test
+    public void setBuffering_enabled() throws Exception {
+        assertBufferingEnabled("setBuffering_enabled");
+    }
+
+    private void assertBufferingEnabled(String id) throws Exception {
+        initPipeline(id);
+
+        getInvocationContext("http://localhost/app1/myscreen");
+        initRequestContext();
+
+        brc = findRequestContext(newRequest, BufferedRequestContext.class);
+        brc.setBuffering(false);
+        assertEquals(false, brc.isBuffering());
+
+        pipeline.newInvocation().invoke();
+        assertEquals(true, brc.isBuffering());
+    }
+
+    @Test
+    public void setBuffering_disabled() throws Exception {
+        initPipeline("setBuffering_disabled");
+
+        getInvocationContext("http://localhost/app1/myscreen");
+        initRequestContext();
+
+        brc = findRequestContext(newRequest, BufferedRequestContext.class);
+        assertEquals(true, brc.isBuffering());
+
+        pipeline.newInvocation().invoke();
+        assertEquals(false, brc.isBuffering());
+    }
+
+    @Test
+    public void setBuffering_illegalState() throws Exception {
+        initPipeline("setBuffering_disabled");
+
+        getInvocationContext("http://localhost/app1/myscreen");
+        initRequestContext();
+
+        brc = findRequestContext(newRequest, BufferedRequestContext.class);
+        assertEquals(true, brc.isBuffering());
+
+        newResponse.getWriter();
+
+        pipeline.newInvocation().invoke();
+        assertEquals(true, brc.isBuffering()); // unchanged
+    }
+}