yacy_search_server/source/de/anomic/soap/ServerContext.java

package de.anomic.soap;

//ServerContext.java 
//------------------------
//part of YaCy
//(C) by Michael Peter Christen; mc@anomic.de
//first published on http://www.anomic.de
//Frankfurt, Germany, 2005
//
//this file was contributed by Martin Thelian
//last major change: $LastChangedDate$ by $LastChangedBy$
//Revision: $LastChangedRevision$
//
//This program 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 2 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 General Public License for more details.
//
//You should have received a copy of the GNU General Public License
//along with this program; if not, write to the Free Software
//Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
//Using this software in any meaning (reading, learning, copying, compiling,
//running) means that you agree that the Author(s) is (are) not responsible
//for cost, loss of data or any harm that may be caused directly or indirectly
//by usage of this softare or this documentation. The usage of this software
//is on your own risk. The installation and usage (starting/running) of this
//software may allow other people or application to access your computer and
//any attached devices and is highly dependent on the configuration of the
//software which must be done by the user of the software; the author(s) is
//(are) also not responsible for proper configuration and usage of the
//software, even if provoked by documentation provided together with
//the software.
//
//Any changes to this file according to the GPL as documented in the file
//gpl.txt aside this file in the shipment you received can be done to the
//lines that follows this copyright notice here, but changes must not be
//done inside the copyright notive above. A re-distribution must contain
//the intact and unchanged copyright notice.
//Contributions and changes to the program code must be marked as such.

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.lang.reflect.Method;
import java.util.HashMap;

import org.apache.axis.AxisFault;

import de.anomic.http.httpHeader;
import de.anomic.http.httpTemplate;
import de.anomic.server.serverClassLoader;
import de.anomic.server.serverObjects;
import de.anomic.server.serverSwitch;

public class ServerContext {
	
    protected String rootPath;
    protected serverClassLoader provider;
    protected HashMap templates;
    protected serverSwitch switchboard;
	
	
	public ServerContext(String root, serverClassLoader cLoader, HashMap templateMap, serverSwitch switchb) {
        this.rootPath      = root;       
        this.provider      = cLoader;
        this.templates     = templateMap;
        this.switchboard   = switchb;		
	}
	
	public serverClassLoader getProvider() {
		return this.provider;
	}
	
    /**
     * This function is called by the service functions to
     * invoke the desired server-internal method and to generate
     * a output document using one of the available templates.
     * 
     * @param templateName
     * @param args
     * @return the output document
     * @throws AxisFault
     */
    public byte[] writeTemplate(String templateName, serverObjects args, httpHeader requestHeader) throws AxisFault {
        try {
        	// invoke servlet
        	serverObjects tp = invokeServlet(templateName,args,requestHeader);
            
        	// generate output
        	byte[] result = buildServletOutput(templateName, tp);
            return result; 
        } catch (Exception e) {
    		if (e instanceof AxisFault) throw (AxisFault) e;
    		
    		// create a new AxisFault Object
    		throw new AxisFault(e.getMessage());
        }
    }    
    
    public byte[] buildServletOutput(String templateName, serverObjects tp) throws AxisFault {
    	try {
    		File templateFile = getTemplateFile(templateName);
    		
    		// generating the output document
    		ByteArrayOutputStream o = new ByteArrayOutputStream();
    		FileInputStream fis = new FileInputStream(templateFile);
    		httpTemplate.writeTemplate(fis, o, tp, "-UNRESOLVED_PATTERN-".getBytes("UTF-8"));
    		o.close();
    		fis.close();
    		
    		// convert it into a byte array and send it back as result
    		byte[] result = o.toByteArray();            
    		return result; 
    	} catch (Exception e) {
    		if (e instanceof AxisFault) throw (AxisFault) e;
    		
    		// create a new AxisFault Object
    		throw new AxisFault(e.getMessage());
    	}    	
    }
    
    public serverObjects invokeServlet(String templateName, serverObjects args, httpHeader requestHeader) throws AxisFault {
    	try {
    		// getting the template class file
    		File rc = getServletClassFile(templateName);
    		
    		// invoke the desired method
    		serverObjects tp = (serverObjects) rewriteMethod(rc).invoke(null, new Object[] {requestHeader, args, this.switchboard});
    		
    		// testing if a authentication was needed by the invoked method
    		validateAuthentication(tp);
    		
    		// adding all available templates
    		tp.putAll(this.templates);
    		
    		// return result
    		return tp;
    	} catch (Exception e) {
    		if (e instanceof AxisFault) throw (AxisFault) e;
    		
    		e.printStackTrace();
    		
    		// create a new AxisFault Object
    		throw new AxisFault(e.getMessage());
    	}        
    }
    
    public File getTemplateFile(String templateName) {
    	// determining the proper class that should be invoked
    	File file = new File(this.rootPath, templateName);     
    	return file;
    }
    
    public File getServletClassFile(String templateName) {
    	File templateFile = getTemplateFile(templateName);
    	File templateClassFile = getServletClassFile(templateFile);
    	return templateClassFile;
    }
    
    public File getServletClassFile(File templateFile) {    	 
    	File templateClassFile = rewriteClassFile(templateFile);    	
    	return templateClassFile;
    }
    
    /**
     * This method was copied from the {@link httpdFileHandler httpdFileHandler-class}
     * @param template
     * @return the .class-{@link File} belonging to the given template or <code>null</code>
     * if no fitting .class-{@link File} does exist
     */
    protected File rewriteClassFile(File template) {
        try {
            String f = template.getCanonicalPath();
            int p = f.lastIndexOf(".");
            if (p < 0) return null;
            f = f.substring(0, p) + ".class";
            //System.out.println("constructed class path " + f);
            File cf = new File(f);
            if (cf.exists()) return cf;
            return null;
        } catch (IOException e) {
            return null;
        }
    }    
    
    /**
     * This method was copied from the {@link httpdFileHandler httpdFileHandler-class}
     * @param classFile
     * @return the <code>resond({@link httpHeader}, {@link serverObjects}, {@link serverSwitch})</code>
     * {@link Method} of the specified class file or <code>null</code> if this file doesn't contain
     * such a method
     */    
    protected Method rewriteMethod(File classFile) {
        Method m = null;
        // now make a class out of the stream
        try {
            //System.out.println("**DEBUG** loading class file " + classFile);
            Class c = this.provider.loadClass(classFile);
            Class[] params = new Class[] {
                    httpHeader.class,     // Class.forName("de.anomic.http.httpHeader"),
                    serverObjects.class,  // Class.forName("de.anomic.server.serverObjects"),
                    serverSwitch.class }; // Class.forName("de.anomic.server.serverSwitch")};
            m = c.getMethod("respond", params);
        } catch (ClassNotFoundException e) {
            System.out.println("INTERNAL ERROR: class " + classFile + " is missing:" + e.getMessage()); 
        } catch (NoSuchMethodException e) {
            System.out.println("INTERNAL ERROR: method respond not found in class " + classFile + ": " + e.getMessage());
        }
        //System.out.println("found method: " + m.toString());
        return m;
    }
    
    
    /**
     * This function is used to test if an invoked method requires authentication
     * 
     * @param tp the properties returned by a previous method invocation
     * 
     * @throws AxisFault if an authentication was required.
     */
    protected void validateAuthentication(serverObjects tp) throws AxisFault {
        // check if the servlets requests authentification
        if (tp.containsKey("AUTHENTICATE")) {
            throw new AxisFault("log-in required");
        }             
    }      
}