Refactoring of the Proxy service

src/main/java/net/sourceforge/plantuml/servlet/ProxyServlet.java

@@ -0,0 +1,120 @@
+/* ========================================================================
+ * PlantUML : a free UML diagram generator
+ * ========================================================================
+ *
+ * Project Info:  http://plantuml.sourceforge.net
+ * 
+ * This file is part of PlantUML.
+ *
+ * PlantUML is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * PlantUML distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+ * USA.
+ */
+package net.sourceforge.plantuml.servlet;
+
+import java.io.IOException;
+import java.net.URL;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import javax.servlet.RequestDispatcher;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import HTTPClient.CookieModule;
+import HTTPClient.HTTPConnection;
+import HTTPClient.HTTPResponse;
+import HTTPClient.ModuleException;
+import HTTPClient.ParseException;
+
+import net.sourceforge.plantuml.FileFormat;
+import net.sourceforge.plantuml.FileFormatOption;
+import net.sourceforge.plantuml.SourceStringReader;
+
+/* 
+ * Proxy servlet of the webapp.
+ * This servlet retrieves the diagram source of a web resource (web html page)
+ * and renders it.
+ */
+@SuppressWarnings("serial")
+public class ProxyServlet extends HttpServlet {
+
+    private static final Pattern proxyPattern = Pattern.compile("/\\w+/proxy/((\\d+)/)?((\\w+)/)?(http://.*)");
+    private String format;
+    
+    @Override
+    public void doGet(HttpServletRequest request, HttpServletResponse response)
+            throws IOException, ServletException {
+
+        final String uri = request.getRequestURI();
+
+        Matcher proxyMatcher = proxyPattern.matcher(uri);
+        if (proxyMatcher.matches()) {
+            String num = proxyMatcher.group(2); // Optional number of the diagram source
+            format = proxyMatcher.group(4); // Expected format of the generated diagram
+            String sourceURL = proxyMatcher.group(5);
+            handleImageProxy(response, num, sourceURL);
+        } else {
+            request.setAttribute("net.sourceforge.plantuml.servlet.decoded", "ERROR Invalid proxy syntax : " + uri);
+            request.removeAttribute("net.sourceforge.plantuml.servlet.encoded");
+
+            // forward to index.jsp
+            RequestDispatcher dispatcher = request.getRequestDispatcher("/index.jsp");
+            dispatcher.forward(request, response);
+        }
+    }
+    
+    private void handleImageProxy(HttpServletResponse response, String num, String source) throws IOException {
+        SourceStringReader reader = new SourceStringReader(getSource(source));
+        int n = num == null ? 0 : Integer.parseInt(num);
+        
+        reader.generateImage(response.getOutputStream(), n, new FileFormatOption(getOutputFormat()));
+    }
+
+    private String getSource( String uri) throws IOException {
+        CookieModule.setCookiePolicyHandler(null);
+
+        final Pattern p = Pattern.compile("http://[^/]+(/?.*)");
+        final Matcher m = p.matcher(uri);
+        if (m.find() == false) {
+            throw new IOException(uri);
+        }
+        final URL url = new URL(uri);
+        final HTTPConnection httpConnection = new HTTPConnection(url);
+        try {
+            final HTTPResponse resp = httpConnection.Get(m.group(1));
+            return resp.getText();
+        } catch (ModuleException e) {
+            throw new IOException(e.toString());
+        } catch (ParseException e) {
+            throw new IOException(e.toString());
+        }
+    }
+
+    private FileFormat getOutputFormat() {
+        if (format==null) {
+            return FileFormat.PNG;
+        }
+        if (format.equals("svg")) {
+            return FileFormat.SVG;
+        }
+        if (format.equals("txt")) {
+            return FileFormat.ATXT;
+        }
+        return FileFormat.PNG;
+    }    
+
+}

src/main/java/net/sourceforge/plantuml/servlet/package.html

@@ -3,10 +3,10 @@
 <p>This package is in charge of the JEE PlantUml Server.</p>
 <p>there are 2 kind of servlets in this package :<br>
 - Interactive servlets : Welcome, PlantUmlServlet that are in charge of the web pages dedicated to human users.<br>
-- Service servlets : ImgServlet, SvgServlet that only produce a diagram as output.<br>
+- Service servlets : ImgServlet, SvgServlet, AsciiServlet, ProxyServlet that only produce a diagram as output.<br>
 <br>
 Structure of the service part of the PlantUmlServer: <br>
-<img src="http://www.plantuml.com/plantuml/img/XP3DJiCm48JlaV8EUmnIymPSAg723KJ40pZsDbd9ZbtlEX8gl3laXv2q_1mz-dPcF2qP17H1Ni6Xgp5odhLhJLfljjgHq0wIgbcYqWBQAcPuSVQEL1ELgp3sf17EUGOGKcr9G-_9WF7tACM3I1WGY_ACfuGi44yxsCWSVCS8aSFDOB94pMwLHEeQQ50gdwB6uaj9aRO71x9uyD4f6UZ79279z2u-mVSycyhFpPVWiVg5MFnSSRVEE8xfusSPEpCxVDTpTafT-gqiuVQjBAzdpBFhPKVogMlcor-HglyNsRCc-WFovUKE7m00" />
+<img src="http://www.plantuml.com/plantuml/img/XP11ReCm44NtFiKiYHHkq4sbAEskLL4EOCm4HhAnCnwZHcdltb0eXIHjbdoU_d-UXYe4T46EuD2Lo54ryqWQNosYFQ4z9xgCmje86AjZX9sp6z8rQrSWTsGGJWeWfDAIWSvJ1PL_GicUHK9FM9GtF2IC0dnOmoAEmRSHWMDOdJkceR6i4AQsXXgby8aDPZz9ObhmMxAuzUoqzF1Baf1a-CvMwbCDtgFqDDfRNsJPRRlrV63VBty_Cs9RZGM_PixsYvFPh0yUFlBy-dh_iA_ituzZegxFFZ1jVOSekdl4OpH4VpC-lxoJcflT-Fy5" />
 </p>
 </body>
 </html>

src/main/webapp/WEB-INF/web.xml

@@ -27,6 +27,10 @@
 		<servlet-name>asciiservlet</servlet-name>
 		<servlet-class>net.sourceforge.plantuml.servlet.AsciiServlet</servlet-class>
 	</servlet>
+    <servlet>
+        <servlet-name>proxyservlet</servlet-name>
+        <servlet-class>net.sourceforge.plantuml.servlet.ProxyServlet</servlet-class>
+    </servlet>
 	<!-- Patterns of the servlet -->
 	<servlet-mapping>
 		<servlet-name>welcome</servlet-name>
@@ -57,7 +61,7 @@
 		<url-pattern>/start/*</url-pattern>
 	</servlet-mapping>
 	<servlet-mapping>
-		<servlet-name>plantumlservlet</servlet-name>
+		<servlet-name>proxyservlet</servlet-name>
 		<url-pattern>/proxy/*</url-pattern>
 	</servlet-mapping>
 	<error-page>