yacy_search_server/htroot/ViewFile.java

//ViewFile.java
//-----------------------
//part of YaCy
//(C) by Michael Peter Christen; mc@anomic.de
//first published on http://www.anomic.de
//Frankfurt, Germany, 2004

//last major change: 12.07.2004

//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.

//you must compile this file with
//javac -classpath .:../Classes Status.java
//if the shell's current path is HTROOT

import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.util.Enumeration;

import de.anomic.data.wikiCode;
import de.anomic.http.httpHeader;
import de.anomic.http.httpc;
import de.anomic.net.URL;
import de.anomic.plasma.plasmaCrawlLURLEntry;
import de.anomic.plasma.plasmaHTCache;
import de.anomic.plasma.plasmaParserDocument;
import de.anomic.plasma.plasmaSwitchboard;
import de.anomic.plasma.cache.IResourceInfo;
import de.anomic.plasma.crawler.plasmaCrawlerException;
import de.anomic.plasma.parser.ParserException;
import de.anomic.server.serverFileUtils;
import de.anomic.server.serverObjects;
import de.anomic.server.serverSwitch;

public class ViewFile {

    public static final int VIEW_MODE_NO_TEXT = 0;
    public static final int VIEW_MODE_AS_PLAIN_TEXT = 1;
    public static final int VIEW_MODE_AS_PARSED_TEXT = 2;
    public static final int VIEW_MODE_AS_PARSED_SENTENCES = 3;
    public static final int VIEW_MODE_AS_IFRAME = 4;

    public static final String[] highlightingColors = new String[] {
        "255,255,100",
        "255,155,155",
        "0,255,0",
        "0,255,255",
        "204,153,0",
        "204,153,255"
    };

    public static serverObjects respond(httpHeader header, serverObjects post, serverSwitch env) {

        serverObjects prop = new serverObjects();
        plasmaSwitchboard sb = (plasmaSwitchboard)env;     

        if (post != null && post.containsKey("words"))
            try {
                prop.put("error_words",URLEncoder.encode((String) post.get("words"), "UTF-8"));
            } catch (UnsupportedEncodingException e1) {
                // ignore this. this should not occure
            }


            // getting the url hash from which the content should be loaded
            String urlHash = post.get("urlHash","");       
            if (urlHash.equals("")) {
                prop.put("error",1);
                prop.put("viewMode",VIEW_MODE_NO_TEXT);
                return prop;
            }

            String viewMode = post.get("viewMode","sentences");

            // getting the urlEntry that belongs to the url hash
            plasmaCrawlLURLEntry urlEntry = null;
            urlEntry = sb.urlPool.loadedURL.load(urlHash, null);
            if (urlEntry == null) {
                prop.put("error",2);
                prop.put("viewMode",VIEW_MODE_NO_TEXT);
                return prop;
            }            

            // gettin the url that belongs to the entry
            URL url = urlEntry.url();
            if (url == null) {
                prop.put("error",3);
                prop.put("viewMode",VIEW_MODE_NO_TEXT);
                return prop;
            }    

            // loading the resource content as byte array
            InputStream resource = null;
            long resourceLength = -1;
            IResourceInfo resInfo = null;
            String resMime = null;
            try {
                // trying to load the resource body
                resource = sb.cacheManager.getResourceContentStream(url);
                resourceLength = sb.cacheManager.getResourceContentLength(url);

                // if the resource body was not cached we try to load it from web
                if (resource == null) {
                    plasmaHTCache.Entry entry = null;
                    try {
                        entry = sb.snippetCache.loadResourceFromWeb(url, 5000, false);
                    } catch (plasmaCrawlerException e) {
                        prop.put("error",4);
                        prop.put("error_errorText",e.getMessage());
                        prop.put("viewMode",VIEW_MODE_NO_TEXT);                        
                        return prop;
                    }

                    if (entry != null) {
                        resInfo = entry.getDocumentInfo();
                        resource = sb.cacheManager.getResourceContentStream(url);
                        resourceLength = sb.cacheManager.getResourceContentLength(url);
                    }

                    if (resource == null) {
                        prop.put("error",4);
                        prop.put("error_errorText","No resource available");
                        prop.put("viewMode",VIEW_MODE_NO_TEXT);
                        return prop;
                    } 
                }

                // try to load resource metadata
                if (resInfo == null) {

                    // try to load the metadata from cache
                    try {
                        resInfo = sb.cacheManager.loadResourceInfo(urlEntry.url());
                    } catch (Exception e) { /* ignore this */}

                    // if the metadata where not cached try to load it from web
                    if (resInfo == null) {
                        String protocol = url.getProtocol();
                        if (!((protocol.equals("http") || protocol.equals("https")))) {
                            prop.put("error",6);
                            prop.put("viewMode",VIEW_MODE_NO_TEXT);
                            return prop;                                
                        }

                        httpHeader responseHeader = httpc.whead(url,url.getHost(),5000,null,null,sb.remoteProxyConfig);
                        if (responseHeader == null) {
                            prop.put("error",4);
                            prop.put("error_errorText","Unable to load resource metadata.");
                            prop.put("viewMode",VIEW_MODE_NO_TEXT);
                            return prop;
                        } 
                        try {
                            resInfo = sb.cacheManager.getResourceInfoFactory().buildResourceInfoObj(url, responseHeader);
                        } catch (Exception e) {
                            prop.put("error",4);
                            prop.put("error_errorText",e.getMessage());
                            prop.put("viewMode",VIEW_MODE_NO_TEXT);
                            return prop;
                        }
                        resMime = responseHeader.mime();
                    }
                } else {
                    resMime = resInfo.getMimeType();
                }
            } catch (IOException e) {
                if (resource != null) try { resource.close(); } catch (Exception ex) {/* ignore this */}
                prop.put("error",4);
                prop.put("error_errorText",e.getMessage());
                prop.put("viewMode",VIEW_MODE_NO_TEXT);
                return prop; 
            } 
            
            if (viewMode.equals("plain")) {
                
                // TODO: how to handle very large files here ?
                String content;
                try {
                    content = new String(serverFileUtils.read(resource),"UTF-8");
                } catch (Exception e) {
                    prop.put("error",4);
                    prop.put("error_errorText",e.getMessage());
                    prop.put("viewMode",VIEW_MODE_NO_TEXT);
                    return prop;                     
                } finally {
                    if (resource != null) try { resource.close(); } catch (Exception e) {/* ignore this */}
                }
                
                content = content.replaceAll("<","&lt;")
                .replaceAll(">","&gt;")
                .replaceAll("\"","&quot;")
                .replaceAll("\n","<br>")
                .replaceAll("\t","&nbsp;&nbsp;&nbsp;&nbsp;");

                prop.put("error",0);
                prop.put("viewMode",VIEW_MODE_AS_PLAIN_TEXT);
                prop.put("viewMode_plainText",content); 
            } else if (viewMode.equals("iframe")) {
                prop.put("viewMode",VIEW_MODE_AS_IFRAME);
                prop.put("viewMode_url",url.toString());                
            } else if (viewMode.equals("parsed") || viewMode.equals("sentences")) {
                // parsing the resource content
                plasmaParserDocument document = null;
                try {
                    document = sb.snippetCache.parseDocument(url, resourceLength, resource,resInfo);
                    if (document == null) {
                        prop.put("error",5);
                        prop.put("error_errorText","Unknown error");
                        prop.put("viewMode",VIEW_MODE_NO_TEXT);
                        return prop;                
                    }
                } catch (ParserException e) {
                    prop.put("error",5);
                    prop.put("error_errorText",e.getMessage());
                    prop.put("viewMode",VIEW_MODE_NO_TEXT);
                    return prop;     
                } finally {
                    if (resource != null) try { resource.close(); } catch (Exception e) {/* ignore this */}
                }
                
                resMime = document.getMimeType();

                if (viewMode.equals("parsed")) {
                    String content = new String(document.getTextBytes());
                    content = wikiCode.replaceHTML(content); //added by Marc Nause
                    content = content.replaceAll("\n","<br>")
                    .replaceAll("\t","&nbsp;&nbsp;&nbsp;&nbsp;");

                    prop.put("viewMode",VIEW_MODE_AS_PARSED_TEXT);
                    prop.put("viewMode_parsedText",content);
                } else {
                    prop.put("viewMode",VIEW_MODE_AS_PARSED_SENTENCES);
                    final Enumeration sentences = document.getSentences(null); // FIXME: apply correct charset

                    boolean dark = true;
                    int i = 0;
                    if (sentences != null) while (sentences.hasMoreElements()) {
                        String currentSentence = wikiCode.replaceHTML((String) sentences.nextElement());

                        // Search word highlighting
                        String words = post.get("words",null);
                        if (words != null) {
                            try {
                                words = URLDecoder.decode(words,"UTF-8");
                            } catch (UnsupportedEncodingException e) {}

                            String[] wordArray = words.substring(1,words.length()-1).split(",");
                            for (int j=0; j < wordArray.length; j++) {
                                String currentWord = wordArray[j].trim(); 
                                currentSentence = currentSentence.replaceAll(currentWord,
                                        "<b style=\"color: black; background-color: rgb(" + highlightingColors[j%6] + ");\">" + currentWord + "</b>");
                            }
                        }

                        prop.put("viewMode_sentences_" + i + "_nr",Integer.toString(i+1)); 
                        prop.put("viewMode_sentences_" + i + "_text",currentSentence);   
                        prop.put("viewMode_sentences_" + i + "_dark",((dark) ? 1 : 0) ); dark=!dark;
                        i++;
                    }
                    prop.put("viewMode_sentences", i);

                } 
                if (document != null) document.close();
            }
            prop.put("error",0);
            prop.put("error_url",url.toString());                
            prop.put("error_hash",urlHash);
            prop.put("error_wordCount",Integer.toString(urlEntry.wordCount()));
            prop.put("error_desc",urlEntry.descr());
            prop.put("error_size",urlEntry.size());
            prop.put("error_mimeType",resMime);

            return prop;
    }

}