Implement protocol XML list servlet, include default parameter set for VNC.

guacamole/src/main/java/net/sourceforge/guacamole/net/basic/crud/protocols/List.java

@@ -0,0 +1,222 @@
+package net.sourceforge.guacamole.net.basic.crud.protocols;
+
+/*
+ *  Guacamole - Clientless Remote Desktop
+ *  Copyright (C) 2010  Michael Jumper
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is 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 Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import java.io.BufferedInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import javax.xml.stream.XMLOutputFactory;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamWriter;
+import net.sourceforge.guacamole.GuacamoleException;
+import net.sourceforge.guacamole.GuacamoleServerException;
+import net.sourceforge.guacamole.net.auth.UserContext;
+import net.sourceforge.guacamole.net.basic.AuthenticatingHttpServlet;
+import net.sourceforge.guacamole.net.basic.ProtocolInfo;
+import net.sourceforge.guacamole.net.basic.ProtocolParameter;
+import net.sourceforge.guacamole.net.basic.ProtocolParameterOption;
+import net.sourceforge.guacamole.net.basic.xml.DocumentHandler;
+import net.sourceforge.guacamole.net.basic.xml.protocol.ProtocolTagHandler;
+import org.xml.sax.InputSource;
+import org.xml.sax.SAXException;
+import org.xml.sax.XMLReader;
+import org.xml.sax.helpers.XMLReaderFactory;
+
+/**
+ * Simple HttpServlet which outputs XML containing a list of all visible
+ * protocols.
+ *
+ * @author Michael Jumper
+ */
+public class List extends AuthenticatingHttpServlet {
+
+    /**
+     * Parses the given XML file, returning the parsed ProtocolInfo.
+     * 
+     * @param input An input stream containing XML describing the parameters
+     *              associated with a protocol supported by Guacamole.
+     * @return A new ProtocolInfo object which contains the parameters described
+     *         by the XML file parsed.
+     * @throws GuacamoleException If an error occurs while parsing the XML file.
+     */
+    private ProtocolInfo getProtocol(InputStream input)
+            throws GuacamoleException {
+
+        // Parse document
+        try {
+
+            // Get handler for root element
+            ProtocolTagHandler protocolTagHandler =
+                    new ProtocolTagHandler();
+
+            // Set up document handler
+            DocumentHandler contentHandler = new DocumentHandler(
+                    "protocol", protocolTagHandler);
+
+            // Set up XML parser
+            XMLReader parser = XMLReaderFactory.createXMLReader();
+            parser.setContentHandler(contentHandler);
+
+            // Read and parse file
+            InputStream xml = new BufferedInputStream(input);
+            parser.parse(new InputSource(xml));
+            xml.close();
+
+            // Return parsed protocol
+            return protocolTagHandler.asProtocolInfo();
+
+        }
+        catch (IOException e) {
+            throw new GuacamoleException("Error reading basic user mapping file.", e);
+        }
+        catch (SAXException e) {
+            throw new GuacamoleException("Error parsing basic user mapping XML.", e);
+        }
+
+    }
+
+    /**
+     * Given an XML stream and a fully-populated ProtocolInfo object, writes
+     * out the corresponding protocol XML describing all available parameters.
+     * 
+     * @param xml The XMLStreamWriter to use to write the XML.
+     * @param protocol The ProtocolInfo object to read parameters and protocol
+     *                 information from.
+     * @throws XMLStreamException If an error occurs while writing the XML.
+     */
+    private void writeProtocol(XMLStreamWriter xml, ProtocolInfo protocol)
+            throws XMLStreamException {
+
+        // Write protocol 
+        xml.writeStartElement("protocol");
+        xml.writeAttribute("name", protocol.getName());
+        xml.writeAttribute("title", protocol.getTitle());
+
+        // Write parameters
+        for (ProtocolParameter param : protocol.getParameters()) {
+
+            // Write param tag
+            xml.writeStartElement("param");
+            xml.writeAttribute("name", param.getName());
+            xml.writeAttribute("title", param.getTitle());
+
+            // Write type
+            switch (param.getType()) {
+
+                // Text parameter
+                case TEXT:
+                    xml.writeAttribute("type", "text");
+                    break;
+
+                // Password parameter
+                case PASSWORD:
+                    xml.writeAttribute("type", "password");
+                    break;
+
+                // Numeric parameter
+                case NUMERIC:
+                    xml.writeAttribute("type", "numeric");
+                    break;
+
+                // Boolean parameter
+                case BOOLEAN:
+                    xml.writeAttribute("type", "boolean");
+                    break;
+
+                // Enumerated parameter
+                case ENUM:
+                    xml.writeAttribute("type", "enum");
+                    break;
+
+                // If unknown, fail explicitly
+                default:
+                    throw new UnsupportedOperationException(
+                        "Parameter type not supported: " + param.getType());
+                    
+            }
+            
+            // Write options
+            for (ProtocolParameterOption option : param.getOptions()) {
+                xml.writeStartElement("option");
+                xml.writeAttribute("value", option.getValue());
+                xml.writeCharacters(option.getTitle());
+                xml.writeEndElement();
+            }
+
+            // End parameter
+            xml.writeEndElement();
+            
+        }
+        
+        // End protocol 
+        xml.writeEndElement();
+
+    }
+    
+    @Override
+    protected void authenticatedService(
+            UserContext context,
+            HttpServletRequest request, HttpServletResponse response)
+    throws GuacamoleException {
+
+        // Do not cache
+        response.setHeader("Cache-Control", "no-cache");
+
+        // Write actual XML
+        try {
+
+            // Write XML content type
+            response.setHeader("Content-Type", "text/xml");
+
+            XMLOutputFactory outputFactory = XMLOutputFactory.newInstance();
+            XMLStreamWriter xml = outputFactory.createXMLStreamWriter(response.getWriter());
+
+            // Begin document
+            xml.writeStartDocument();
+            xml.writeStartElement("protocols");
+
+            // Read from classpath
+            InputStream stream = List.class.getResourceAsStream(
+                    "/net/sourceforge/guacamole/net/protocols/vnc.xml");
+            if (stream == null)
+                throw new IOException("Could not read VNC XML.");
+
+            // Parse and write protocol
+            ProtocolInfo protocol = getProtocol(stream);
+            writeProtocol(xml, protocol);
+           
+            // End document
+            xml.writeEndElement();
+            xml.writeEndDocument();
+
+        }
+        catch (XMLStreamException e) {
+            throw new GuacamoleServerException(
+                    "Unable to write protocol list XML.", e);
+        }
+        catch (IOException e) {
+            throw new GuacamoleServerException(
+                    "I/O error writing protocol list XML.", e);
+        }
+
+    }
+
+}

guacamole/src/main/java/net/sourceforge/guacamole/net/basic/crud/protocols/package-info.java

@@ -0,0 +1,6 @@
+
+/**
+ * Servlets dedicated to CRUD operations related to protocols.
+ */
+package net.sourceforge.guacamole.net.basic.crud.protocols;
+

guacamole/src/main/resources/net/sourceforge/guacamole/net/protocols/vnc.xml

@@ -0,0 +1,13 @@
+<protocol name="vnc" title="VNC">
+
+    <param name="hostname"    type="text"    title="Hostname"/>
+    <param name="port"        type="numeric" title="Port"/>
+    <param name="read-only"   type="boolean" title="Read-only"/>
+    <param name="color-depth" type="text"    title="Color depth">
+        <option value="8">256 color</option>
+        <option value="16">Low color (16-bit)</option>
+        <option value="24">True color (24-bit)</option>
+        <option value="32">True color (32-bit)</option>
+    </param>
+
+</protocol>

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

@@ -154,6 +154,17 @@
         <url-pattern>/permissions</url-pattern>
     </servlet-mapping>
 
+    <!-- Protocol List Servlet -->
+    <servlet>
+        <description>Protocol list servlet.</description>
+        <servlet-name>Protocols</servlet-name>
+        <servlet-class>net.sourceforge.guacamole.net.basic.crud.protocols.List</servlet-class>
+    </servlet>
+    <servlet-mapping>
+        <servlet-name>Protocols</servlet-name>
+        <url-pattern>/protocols</url-pattern>
+    </servlet-mapping>
+
     <!-- Guacamole Tunnel Servlet -->
     <servlet>
         <description>Tunnel servlet.</description>