001package org.apache.turbine.services.jsp; 002 003 004/* 005 * Licensed to the Apache Software Foundation (ASF) under one 006 * or more contributor license agreements. See the NOTICE file 007 * distributed with this work for additional information 008 * regarding copyright ownership. The ASF licenses this file 009 * to you under the Apache License, Version 2.0 (the 010 * "License"); you may not use this file except in compliance 011 * with the License. You may obtain a copy of the License at 012 * 013 * http://www.apache.org/licenses/LICENSE-2.0 014 * 015 * Unless required by applicable law or agreed to in writing, 016 * software distributed under the License is distributed on an 017 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 018 * KIND, either express or implied. See the License for the 019 * specific language governing permissions and limitations 020 * under the License. 021 */ 022 023 024import java.io.File; 025import java.io.IOException; 026import java.util.Arrays; 027 028import javax.servlet.RequestDispatcher; 029import javax.servlet.http.HttpServletRequest; 030 031import org.apache.commons.configuration2.Configuration; 032import org.apache.commons.lang3.StringUtils; 033import org.apache.logging.log4j.LogManager; 034import org.apache.logging.log4j.Logger; 035import org.apache.turbine.Turbine; 036import org.apache.turbine.pipeline.PipelineData; 037import org.apache.turbine.services.InitializationException; 038import org.apache.turbine.services.pull.ApplicationTool; 039import org.apache.turbine.services.pull.tools.TemplateLink; 040import org.apache.turbine.services.template.BaseTemplateEngineService; 041import org.apache.turbine.util.RunData; 042import org.apache.turbine.util.TurbineException; 043 044/** 045 * This is a Service that can process JSP templates from within a Turbine 046 * screen. 047 * 048 * @author <a href="mailto:john.mcnally@clearink.com">John D. McNally</a> 049 * @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a> 050 * @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a> 051 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a> 052 */ 053public class TurbineJspService 054 extends BaseTemplateEngineService 055 implements JspService 056{ 057 /** The base path[s] prepended to filenames given in arguments */ 058 private String[] templatePaths; 059 060 /** The relative path[s] prepended to filenames */ 061 private String[] relativeTemplatePaths; 062 063 /** The buffer size for the output stream. */ 064 private int bufferSize; 065 066 /** Logging */ 067 private static Logger log = LogManager.getLogger(TurbineJspService.class); 068 069 /** 070 * Load all configured components and initialize them. This is 071 * a zero parameter variant which queries the Turbine Servlet 072 * for its config. 073 * 074 * @throws InitializationException Something went wrong in the init 075 * stage 076 */ 077 @Override 078 public void init() 079 throws InitializationException 080 { 081 try 082 { 083 initJsp(); 084 registerConfiguration(JspService.JSP_EXTENSION); 085 setInit(true); 086 } 087 catch (Exception e) 088 { 089 throw new InitializationException( 090 "TurbineJspService failed to initialize", e); 091 } 092 } 093 094 /** 095 * Adds some convenience objects to the request. For example an instance 096 * of TemplateLink which can be used to generate links to other templates. 097 * 098 * @param pipelineData the Turbine PipelineData object 099 */ 100 @Override 101 public void addDefaultObjects(PipelineData pipelineData) 102 { 103 HttpServletRequest req = pipelineData.get(Turbine.class, HttpServletRequest.class); 104 105 // 106 // This is a place where an Application Pull Tool is used 107 // in a regular Java Context. We have no Pull Service with the 108 // Jsp Paging stuff, but we can run our Application Tool by Hand: 109 // 110 ApplicationTool templateLink = new TemplateLink(); 111 templateLink.init(pipelineData); 112 113 req.setAttribute(LINK, templateLink); 114 req.setAttribute(PIPELINE_DATA, pipelineData); 115 } 116 117 /** 118 * Returns the default buffer size of the JspService 119 * 120 * @return The default buffer size. 121 */ 122 @Override 123 public int getDefaultBufferSize() 124 { 125 return bufferSize; 126 } 127 128 /** 129 * executes the JSP given by templateName. 130 * 131 * @param pipelineData A PipelineData Object 132 * @param templateName The template to execute 133 * @param isForward whether to perform a forward or include. 134 * 135 * @throws TurbineException If a problem occurred while executing the JSP 136 */ 137 @Override 138 public void handleRequest(PipelineData pipelineData, String templateName, boolean isForward) 139 throws TurbineException 140 { 141 if(!(pipelineData instanceof RunData)) 142 { 143 throw new RuntimeException("Can't cast to rundata from pipeline data."); 144 } 145 146 RunData data = (RunData)pipelineData; 147 148 /** template name with relative path */ 149 String relativeTemplateName = getRelativeTemplateName(templateName); 150 151 if (StringUtils.isEmpty(relativeTemplateName)) 152 { 153 throw new TurbineException( 154 "Template " + templateName + " not found in template paths"); 155 } 156 157 // get the RequestDispatcher for the JSP 158 RequestDispatcher dispatcher = data.getServletContext() 159 .getRequestDispatcher(relativeTemplateName); 160 161 try 162 { 163 if (isForward) 164 { 165 // forward the request to the JSP 166 dispatcher.forward(data.getRequest(), data.getResponse()); 167 } 168 else 169 { 170 data.getResponse().getWriter().flush(); 171 // include the JSP 172 dispatcher.include(data.getRequest(), data.getResponse()); 173 } 174 } 175 catch (Exception e) 176 { 177 // Let's try hard to send the error message to the browser, to speed up debugging 178 try 179 { 180 data.getResponse().getWriter().print("Error encountered processing a template: " 181 + templateName); 182 e.printStackTrace(data.getResponse().getWriter()); 183 } 184 catch (IOException ignored) 185 { 186 // ignore 187 } 188 189 // pass the exception to the caller according to the general 190 // contract for templating services in Turbine 191 throw new TurbineException( 192 "Error encountered processing a template: " + templateName, e); 193 } 194 } 195 196 /** 197 * executes the JSP given by templateName. 198 * 199 * @param pipelineData A PipelineData Object 200 * @param templateName The template to execute 201 * 202 * @throws TurbineException If a problem occurred while executing the JSP 203 */ 204 @Override 205 public void handleRequest(PipelineData pipelineData, String templateName) 206 throws TurbineException 207 { 208 handleRequest(pipelineData, templateName, false); 209 } 210 211 /** 212 * This method sets up the template cache. 213 */ 214 private void initJsp() 215 throws Exception 216 { 217 Configuration config = getConfiguration(); 218 219 // Set relative paths from config. 220 // Needed for javax.servlet.RequestDispatcher 221 relativeTemplatePaths = config.getStringArray(TEMPLATE_PATH_KEY); 222 223 // Use Turbine Servlet to translate the template paths. 224 templatePaths = new String [relativeTemplatePaths.length]; 225 for (int i=0; i < relativeTemplatePaths.length; i++) 226 { 227 relativeTemplatePaths[i] = warnAbsolute(relativeTemplatePaths[i]); 228 229 templatePaths[i] = Turbine.getRealPath(relativeTemplatePaths[i]); 230 } 231 232 bufferSize = config.getInt(JspService.BUFFER_SIZE_KEY, 233 JspService.BUFFER_SIZE_DEFAULT); 234 } 235 236 /** 237 * Determine whether a given template is available on the 238 * configured template pathes. 239 * 240 * @param template The name of the requested Template 241 * @return True if the template is available. 242 */ 243 @Override 244 public boolean templateExists(String template) 245 { 246 return Arrays.stream(templatePaths).anyMatch(templatePath -> templateExists(templatePath, template)); 247 } 248 249 /** 250 * Determine whether a given template exists on the supplied 251 * template path. This service ATM only supports file based 252 * templates so it simply checks for file existence. 253 * 254 * @param path The absolute (file system) template path 255 * @param template The name of the requested Template 256 * @return True if the template is available. 257 */ 258 private boolean templateExists(String path, String template) 259 { 260 return new File(path, template).exists(); 261 } 262 263 /** 264 * Searches for a template in the default.template path[s] and 265 * returns the template name with a relative path which is 266 * required by <a href="http://java.sun.com/products/servlet/2.3/javadoc/javax/servlet/ServletContext.html#getRequestDispatcher(java.lang.String)"> 267 * javax.servlet.RequestDispatcher</a> 268 * 269 * @param template the name of the template 270 * @return String 271 */ 272 @Override 273 public String getRelativeTemplateName(String template) 274 { 275 String relativeTemplate = warnAbsolute(template); 276 277 // Find which template path the template is in 278 // We have a 1:1 match between relative and absolute 279 // pathes so we can use the index for translation. 280 for (int i = 0; i < templatePaths.length; i++) 281 { 282 if (templateExists(templatePaths[i], relativeTemplate)) 283 { 284 return relativeTemplatePaths[i] + "/" + relativeTemplate; 285 } 286 } 287 return null; 288 } 289 290 /** 291 * Warn if a template name or path starts with "/". 292 * 293 * @param template The template to test 294 * @return The template name with a leading / stripped off 295 */ 296 private String warnAbsolute(String template) 297 { 298 if (template.startsWith("/")) 299 { 300 log.warn("Template {} has a leading /, which is wrong!", template); 301 return template.substring(1); 302 } 303 return template; 304 } 305}