// httpTemplate.java // ------------------------------------- // (C) by Michael Peter Christen; mc@anomic.de // first published on http://www.anomic.de // Frankfurt, Germany, 2004 // last major change: 16.01.2005 // // extended for multi- and alternatives-templates by Alexander Schier // // 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 notice above. A re-distribution must contain // the intact and unchanged copyright notice. // Contributions and changes to the program code must be marked as such. package de.anomic.http; import java.io.BufferedReader; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.io.PushbackInputStream; import java.util.Hashtable; import de.anomic.server.serverFileUtils; import de.anomic.server.logging.serverLog; /** * A template engine, which substitutes patterns in strings
* * The template engine supports four types of templates:
*
    *
  1. Normal templates: the template will be replaced by a string.
  2. *
  3. Multi templates: the template will be used more than one time.
    * i.e. for lists
  4. *
  5. 3. Alternatives: the program chooses one of multiple alternatives.
  6. *
  7. Includes: another file with templates will be included.
  8. *
* * All these templates can be used recursivly.

* HTML-Example
*

 * <html><head></head><body>
 * #{times}#
 * Good #(daytime)#morning::evening#(/daytime)#, #[name]#!(#[num]#. Greeting)<br>
 * #{/times}#
 * </body></html>
 * 
*

* The corresponding Hashtable to use this Template:
* Java Example
*

 * Hashtable pattern;
 * pattern.put("times", 10); //10 greetings
 * for(int i=0;i<=9;i++){
 * 	pattern.put("times_"+i+"_daytime", 1); //index: 1, second Entry, evening
 * 	pattern.put("times_"+i+"_name", "John Connor");
 * 	pattern.put("times_"+i+"_num", (i+1));
 * }
 * 
*

* Recursion
* If you use recursive templates, the templates will be used from * the external to the internal templates. * In our Example, the Template in #{times}##{/times}# will be repeated ten times.
* Then the inner Templates will be applied. *

* The inner templates have a prefix, so they may have the same name as a template on another level, * or templates which are in another recursive template.
* The Prefixes: *

* So the Names in the Hashtable are: * * #(alternative)#::#{repeat}##[test]##{/repeat}##(/alternative)#
* would be adressed as "alternative_repeat_"+number+"_test" */ public final class httpTemplate { private static final byte hash = (byte)'#'; private static final byte[] hasha = {hash}; private static final byte lbr = (byte)'['; private static final byte rbr = (byte)']'; private static final byte[] pOpen = {hash, lbr}; private static final byte[] pClose = {rbr, hash}; private static final byte lcbr = (byte)'{'; private static final byte rcbr = (byte)'}'; private static final byte[] mOpen = {hash, lcbr}; private static final byte[] mClose = {rcbr, hash}; private static final byte lrbr = (byte)'('; private static final byte rrbr = (byte)')'; private static final byte[] aOpen = {hash, lrbr}; private static final byte[] aClose = {rrbr, hash}; private static final byte ps = (byte)'%'; private static final byte[] iOpen = {hash, ps}; private static final byte[] iClose = {ps, hash}; /** * transfer until a specified pattern is found; everything but the pattern is transfered so far * the function returns true, if the pattern is found */ private static boolean transferUntil(PushbackInputStream i, OutputStream o, byte[] pattern) throws IOException { int ppos = 0; int b, bb; boolean equal; while ((b = i.read()) > 0) { if ((b & 0xFF) == pattern[0]) { // read the whole pattern equal = true; for (int n = 1; n < pattern.length; n++) { if (((bb = i.read()) & 0xFF) != pattern[n]) { // push back all i.unread(bb); equal = false; for (int nn = n - 1; nn > 0; nn--) i.unread(pattern[nn]); break; } } if (equal) return true; } o.write(b); } return false; } public static void writeTemplate(InputStream in, OutputStream out, Hashtable pattern, byte[] dflt) throws IOException { writeTemplate(in, out, pattern, dflt, ""); } /** * Reads a input stream, and writes the data with replaced templates on a output stream */ public static void writeTemplate(InputStream in, OutputStream out, Hashtable pattern, byte[] dflt, String prefix) throws IOException { PushbackInputStream pis = new PushbackInputStream(in, 100); ByteArrayOutputStream keyStream; String key; String multi_key; boolean consistent; byte[] replacement; int bb; while (transferUntil(pis, out, hasha)) { bb = pis.read(); keyStream = new ByteArrayOutputStream(); if( (bb & 0xFF) == lcbr ){ //multi if( transferUntil(pis, keyStream, mClose) ){ //close tag //multi_key = "_" + keyStream.toString(); //for _Key bb = pis.read(); if( (bb & 0xFF) != 10){ //kill newline pis.unread(bb); } multi_key = keyStream.toString(); //IMPORTANT: no prefix here keyStream = new ByteArrayOutputStream(); //reset stream /* DEBUG - print key + value try{ System.out.println("Key: "+prefix+multi_key+ "; Value: "+pattern.get(prefix+multi_key)); }catch(NullPointerException e){ System.out.println("Key: "+prefix+multi_key); } */ //this needs multi_key without prefix if( transferUntil(pis, keyStream, (new String(mOpen) + "/" + multi_key + new String(mClose)).getBytes()) ){ bb = pis.read(); if((bb & 0xFF) != 10){ //kill newline pis.unread(bb); } multi_key = prefix + multi_key; //OK, now add the prefix String text=keyStream.toString(); //text between #{key}# an #{/key}# int num=0; if(pattern.containsKey(multi_key) && pattern.get(multi_key) != null){ try{ num=(int)Integer.parseInt((String)pattern.get(multi_key)); // Key contains the iteration number as string }catch(NumberFormatException e){ num=0; } //System.out.println(multi_key + ": " + num); //DEBUG }else{ //0 interations - no display //System.out.println("_"+new String(multi_key)+" is null or does not exist"); //DEBUG } //Enumeration enx = pattern.keys(); while (enx.hasMoreElements()) System.out.println("KEY=" + enx.nextElement()); // DEBUG for(int i=0;i < num;i++ ){ PushbackInputStream pis2 = new PushbackInputStream(new ByteArrayInputStream(text.getBytes())); //System.out.println("recursing with text(prefix="+ multi_key + "_" + i + "_" +"):"); //DEBUG //System.out.println(text); writeTemplate(pis2, out, pattern, dflt, multi_key + "_" + i + "_"); }//for }else{//transferUntil serverLog.logSevere("TEMPLATE", "No Close Key found for #{"+multi_key+"}#"); } } }else if( (bb & 0xFF) == lrbr ){ //alternatives int others=0; String text=""; PushbackInputStream pis2; transferUntil(pis, keyStream, aClose); key = keyStream.toString(); //Caution: Key does not contain prefix /* DEBUG - print key + value try{ System.out.println("Key: "+prefix+key+ "; Value: "+pattern.get(prefix+key)); }catch(NullPointerException e){ System.out.println("Key: "+prefix+key); } */ keyStream=new ByteArrayOutputStream(); //clear boolean byName=false; int whichPattern=0; String patternName=""; if(pattern.containsKey(prefix + key) && pattern.get(prefix + key) != null){ String patternId=(String)pattern.get(prefix + key); try{ whichPattern=(int)Integer.parseInt(patternId); //index }catch(NumberFormatException e){ whichPattern=0; byName=true; patternName=patternId; } }else{ //System.out.println("Pattern \""+new String(prefix + key)+"\" is not set"); //DEBUG } int currentPattern=0; boolean found=false; keyStream = new ByteArrayOutputStream(); //reset stream if(byName){ //TODO: better Error Handling transferUntil(pis, keyStream, (new String("%%"+patternName)).getBytes()); if(pis.available()==0){ serverLog.logSevere("TEMPLATE", "No such Template: %%"+patternName); return; } keyStream=new ByteArrayOutputStream(); transferUntil(pis, keyStream, "::".getBytes()); pis2 = new PushbackInputStream(new ByteArrayInputStream(keyStream.toString().getBytes())); writeTemplate(pis2, out, pattern, dflt, prefix + key + "_"); transferUntil(pis, keyStream, (new String("#(/"+key+")#")).getBytes()); if(pis.available()==0){ serverLog.logSevere("TEMPLATE", "No Close Key found for #("+key+")# (by Name)"); } }else{ while(!found){ bb=pis.read(); if( (bb & 0xFF) == hash){ bb=pis.read(); if( (bb & 0xFF) == lrbr){ transferUntil(pis, keyStream, aClose); //reached the end. output last string. if(keyStream.toString().equals("/" + key)){ pis2 = new PushbackInputStream(new ByteArrayInputStream(text.getBytes())); //this maybe the wrong, but its the last writeTemplate(pis2, out, pattern, dflt, prefix + key + "_"); found=true; }else if(others >0 && keyStream.toString().startsWith("/")){ //close nested others--; text += "#("+keyStream.toString()+")#"; }else{ //nested others++; text += "#("+keyStream.toString()+")#"; } keyStream = new ByteArrayOutputStream(); //reset stream continue; }else{ //is not #( pis.unread(bb);//is processed in next loop bb = (hash);//will be added to text this loop //text += "#"; } }else if( (bb & 0xFF) == ':' && others==0){//ignore :: in nested Expressions bb=pis.read(); if( (bb & 0xFF) == ':'){ if(currentPattern == whichPattern){ //found the pattern pis2 = new PushbackInputStream(new ByteArrayInputStream(text.getBytes())); writeTemplate(pis2, out, pattern, dflt, prefix + key + "_"); transferUntil(pis, keyStream, (new String("#(/"+key+")#")).getBytes());//to #(/key)#. found=true; } currentPattern++; text=""; continue; }else{ text += ":"; } } if(!found){ text += (char)bb; if(pis.available()==0){ serverLog.logSevere("TEMPLATE", "No Close Key found for #("+key+")# (by Index)"); found=true; } } }//while }//if(byName) (else branch) }else if( (bb & 0xFF) == lbr ){ //normal if (transferUntil(pis, keyStream, pClose)) { // pattern detected, write replacement key = prefix + keyStream.toString(); replacement = replacePattern(key, pattern, dflt); //replace /* DEBUG try{ System.out.println("Key: "+key+ "; Value: "+pattern.get(key)); }catch(NullPointerException e){ System.out.println("Key: "+key); } */ serverFileUtils.write(replacement, out); } else { // inconsistency, simply finalize this serverFileUtils.copy(pis, out); return; } }else if( (bb & 0xFF) == ps){ //include String include = ""; String line = ""; keyStream = new ByteArrayOutputStream(); //reset stream if(transferUntil(pis, keyStream, iClose)){ String filename = keyStream.toString(); if(filename.startsWith( Character.toString((char)lbr) ) && filename.endsWith( Character.toString((char)rbr) )){ //simple pattern for filename filename= new String(replacePattern( prefix + filename.substring(1, filename.length()-1), pattern, dflt)); } if ((!filename.equals("")) && (!filename.equals(dflt))) { BufferedReader br = null; try{ br = new BufferedReader(new InputStreamReader(new FileInputStream( new File("htroot", filename) ))); //Read the Include while( (line = br.readLine()) != null ){ include+=line+de.anomic.server.serverCore.crlfString; } }catch(IOException e){ //file not found? serverLog.logSevere("FILEHANDLER","Include Error with file: "+filename); } finally { if (br!=null) try{br.close(); br=null;}catch(Exception e){} } PushbackInputStream pis2 = new PushbackInputStream(new ByteArrayInputStream(include.getBytes())); writeTemplate(pis2, out, pattern, dflt, prefix); } } }else{ //no match, but a single hash (output # + bb) byte[] tmp=new byte[2]; tmp[0]=hash; tmp[1]=(byte)bb; serverFileUtils.write(tmp, out); } } } public static byte[] replacePattern(String key, Hashtable pattern, byte dflt[]){ byte[] replacement; Object value; if (pattern.containsKey(key)) { value = pattern.get(key); if (value instanceof byte[]) replacement = (byte[]) value; else if (value instanceof String) replacement = ((String) value).getBytes(); else replacement = value.toString().getBytes(); } else { replacement = dflt; } return replacement; } public static void main(String[] args) { // arg1 = test input; arg2 = replacement for pattern 'test'; arg3 = default replacement try { InputStream i = new ByteArrayInputStream(args[0].getBytes()); Hashtable h = new Hashtable(); h.put("test", args[1].getBytes()); writeTemplate(new PushbackInputStream(i, 100), System.out, h, args[2].getBytes()); System.out.flush(); } catch (Exception e) { e.printStackTrace(); } } }