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Once finished our textboxes must work like this:

Wiki MarkupAdministrators that use XMLUI interface will notice that Discovery functionality strongly increases searching and browsing by the use of layered navigation and textbox autocomplete among others. To achieve these goals an Apache Solr search server is deployed in \ [dspace-source\]/dspace/solr to take care of all query-reponse handling.  JSPUI interface use an Apache Lucene Directory (located on  \[dspace\]/search ) to search and browse by, but it leaks of previously mentioned
JSPUI interface use an Apache Lucene Directory (located on [dspace]/search ) to search and browse by, but it leaks of previously mentioned functionalities.

We'll use a servlet class to query a SOLR core to generate JSON responses, this responses will be wired to textboxes with autocomplete functionality. Here is a simple diagram of this dataflow.

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First steps: Preparing JSPUI advanced search page

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First of all we'll add jquery and jquery-ui libraries to advanced search .jsp page. This libraries have the necessary code to implement autocomplete behavior. We can add them on head section of advanced search page \ [dspace-source\]/dspace-jspui/dspace-jspui-webapp/src/main/webapp/search/advanced.jsp, or use a on/off switch approach to attach them as described on [Adding jQuery (or other script library) support on JSPUI|DSpaceKB:Adding jQuery (or other script library) support on JSPUI]. In this manual we'll use second approach because it's the fastest way to disable scriptaculous libraries to avoid colliding with jquery (both use the same notation $ for calling functions ).

Wiki MarkupWe'll edit \ [dspace-source\]/dspace-jspui/dspace-jspui-webapp/src/main/webapp/search/advanced.jsp  \\jsp

Code Block

language	html/xml
title	advanced.jsp
collapse	true

...
<%
 //Add this code on top section
 //Generate JSPUI Solr path url
 String scheme = request.getScheme();             // http
 String serverName = request.getServerName();     //request.getServerName();     // hostname.com
 int serverPort = request.getServerPort();        // 80
 String parentContextPath = "";                   //Change this value if dspace not installed on html root folder
 String contextPath = "/jspui";
 String servletPath = "/searchJSON";
 // Reconstruct original requesting URL
 StringBuffer url =  new StringBuffer();
 url.append(scheme).append("://").append(serverName);
 if (serverPort != 80)
 url.append(":").append(serverPort);
 url.append(parentContextPath).append(contextPath).append(servletPath);
 String solrPath = url.toString();

%>
...

<dspace:layout locbar="nolink" titlekey="jsp.search.advanced.title" scriptaculous="off" jquery="on">
<script type="text/javascript" src="<%=request.getContextPath()%>/static/js/autocomplete.js"></script>
<script type="text/javascript">
window.onload = function() {
   monkeyPatchAutocomplete();
   replaceSAXExpression('<%=solrPath %>', 10,'tfield1', 'tquery1');
   replaceSAXExpression('<%=solrPath %>', 10,'tfield2', 'tquery2');
   replaceSAXExpression('<%=solrPath %>', 10,'tfield3', 'tquery3');
}
</script>
...
<!-- Add id field and onchange event call for every search combobox, add id field on search textbox too-->
<select name="field1" id="tfield1" onchange="JavaScript:replaceSAXExpression('<%=solrPath%>', 10 ,'tfield1', 'tquery1');">
<input type="text" name="query1" id="tquery1" value="<%=StringEscapeUtils.escapeHtml(query1)%>" size="30" />
...
<select name="field2" id="tfield2" onchange="JavaScript:replaceSAXExpression('<%=solrPath%>', 10 ,'tfield2', 'tquery2');">
<input type="text" name="query2" id="tquery2" value="<%=StringEscapeUtils.escapeHtml(query2)%>" size="30"/>
...
<select name="field3" id="tfield3" onchange="JavaScript:replaceSAXExpression('<%=solrPath%>', 10 ,'tfield3', 'tquery3');">
<input type="text" name="query3" id="tquery3" value="<%=StringEscapeUtils.escapeHtml(query3)%>" size="30"/>

Adding javascript functions

Wiki MarkupIt's time to create a javascript library file that will contain a pair of functions.  First one will patch autocomplete default behavior and will bold every part of result text that match our typed words. Second one will replace SAX expression used in autocomplete textbox everytime we change select value (we must search by other index). It will reside in \[dspace-source\ First one will patch autocomplete default behavior and will bold every part of result text that match our typed words. Second one will replace SAX expression used in autocomplete textbox everytime we change select value (we must search by other index). It will reside in [dspace-source]/dspace-jspui/dspace-jspui-webapp/src/main/webapp/static/js/autocomplete.js

Code Block

language	javascript
title	autocomplete.js
linenumbers	true
collapse	true

/**
 * Functions used on advanced search page
 */
function monkeyPatchAutocomplete() {
    // don't really need this, but in case I did, I could store it and chain
    var oldFn = $.ui.autocomplete.prototype._renderItem;

    $.ui.autocomplete.prototype._renderItem = function( ul, item){
    	var term = this.term.split(' ').join('|');
    	var re = new RegExp("(" + term + ")", "gi") ;
    	var t = item.label.replace(re,"<b>$1</b>");
    	return $( "<li></li>" )
    	.data( "item.autocomplete", item )
    	.append( "<a>" + t + "</a>" )
    	.appendTo( ul );
    };

}

function replaceSAXExpression(baseUrl , limit ,fieldName, fieldText){
	var field = $('#'+ fieldName).val();
	$('#' + fieldText).val('');
	$('#' + fieldText).autocomplete({
		source: function( request, response ) {
			$.ajax({
				url: baseUrl +"/terms?terms=true&terms.limit=" + limit + "&terms.sort=count&terms.regex.flag=case_insensitive&terms.fl=" + field + "&terms.regex=.*" + request.term + ".*&wt=json",
				dataType: "json",
				data: {
					style: "full",
					maxRows: 5,
					name_startsWith: request.term,
				},
				success: function( data ) {
 					response( $.map( data.terms[field], function( item ) {
						if(!$.isNumeric(item)){
							return{
    							label: item,
    							value: "\"" + item + "\"",
         					}
         				}else {
         					return null;
         				}
         			}
				));}
			});
		},
		minLength: 1,
		select: function( event, ui ) {

		},
		open: function() {
			$( this ).removeClass( "ui-corner-all" ).addClass( "ui-corner-top" );
		},
		close: function() {
			$( this ).removeClass( "ui-corner-top" ).addClass( "ui-corner-all" );
		}
	});
}

Creating a new SOLR core

Wiki MarkupNow we must create a new SOLR core inside \ [dspace-source\]/solr directory. To do so we'll use one of the existing cores and copy it's structure with this command:

Code Block

bash$ cp -R [dspace-source]/dspace/solr/search [dspace-source]/dspace/solr/searchJSPUI
bash$ mkdir [dspace-source]/dspace/solr/searchJSPUI/data
bash$ mkdir [dspace-source]/dspace/solr/searchJSPUI/data/index

Wiki MarkupEdit \ [dspace-source\]/dspace/solr/solr.xml and add one extra line with our new search core.

Code Block

<cores adminPath="/admin/cores">
 <core name="search" instanceDir="search" />
 <core name="statistics" instanceDir="statistics" />
 <core name="searchJSPUI" instanceDir="searchJSPUI" />  <!-- Add this line-->
</cores>

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Overwrite new solr core configuration file \ [dspace-source\]/dspace/solr/searchJSPUI/conf/schema.xml with this file [^schemaschema.xml] to handle lucene indexes generated by JSPUI.

If no modification to search indexes has been done on dspace.cfg file this configuration file will be enough.

Note

If we have added new search fields we must add them to schema.xml file in order to be accessible by SOLR and allow autocomplete funcionality. Example in schema.xml:

Code Block
<field name="publisher" type="text" indexed="true" stored="true" /> <!-- field must have the same name value as we defined in search index in dspace.cfg -->

Wiki MarkupThen we'll edit \ [dspace-source\]/dspace/config/dspace.cfg and modify default JSPUI search index folder:

Code Block
# Where to put search index files search.dir = ${dspace.dir}/solr/searchJSPUI/data/index

...

Creating SearchJSONServlet.java

Wiki MarkupNow we'll create the servlet responsible of reading autocomplete petitions and reponse with solr JSON structures. We could ommit this intermediate class but solr it's blocked from external querys due to security concerns, so this inner class will act as a bridge from client browser querys and internal solr server.
We'll create \ [dspace-source\]/dspace-jspui/dspace-jspui-api/src/main/java/org/dspace/app/webui/servlet/SearchJSONServlet.java class and then will fill it's content with this code:

Code Block

language	java
title	SearchJSONServlet.java
linenumbers	true
collapse	true

package org.dspace.app.webui.servlet;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.transform.stream.StreamResult;

import org.apache.log4j.Logger;
import org.dspace.authorize.AuthorizeException;
import org.dspace.core.Context;

public class SearchJSONServlet extends DSpaceServlet
{
 private static final long serialVersionUID = 1L;
 /** log4j category */
 private static Logger log = Logger.getLogger(SearchJSONServlet.class);

 /**
 * Create an DSpaceServlet Servlet
 */
 public SearchJSONServlet()
 {
 super();
 }

 protected void doDSPost(Context context, HttpServletRequest request,
 HttpServletResponse response) throws ServletException, IOException,
 SQLException, AuthorizeException
 {
 doDSGet(context, request, response);
 }

 protected void doDSGet(Context context, HttpServletRequest request,
 HttpServletResponse response) throws ServletException, IOException,
 SQLException, AuthorizeException
 {
 String pathString = request.getPathInfo();
 String queryString = request.getQueryString();

 //Build localhost solr query path
 String scheme = request.getScheme();             // http
 String serverName = "127.0.0.1";                 // Solr can only be accessed from localhost
 int serverPort = request.getServerPort();        // 80

 String contextPath = "/solr";
 String servletPath = "/searchJSPUI";
 String parentContextPath = "";                  //Change this value if your dspace installation is not on base web server directory
 StringBuffer url =  new StringBuffer();
 url.append(scheme).append("://").append(serverName);
 if (serverPort != 80)
 url.append(":").append(serverPort);
 url.append(parentContextPath).append(contextPath).append(servletPath);
 url.append(pathString + "?");
 url.append(queryString);
 String solrPath = url.toString();

 //Get response from solr server and send it as servlet reponse
 StringBuilder jsonResponse = new StringBuilder();
 URL sorlURL = new URL(solrPath);
 URLConnection solrConnection = sorlURL.openConnection();
 BufferedReader in = new BufferedReader(new InputStreamReader(solrConnection.getInputStream()));
 String inputLine;
 while ((inputLine = in.readLine()) != null)
 jsonResponse.append(inputLine + "\n");
 in.close();
 StreamResult result = new StreamResult(response.getOutputStream());
 response.setHeader("Content-Length", String.valueOf(jsonResponse.length()));
 response.getOutputStream().flush();

 byte[] buf = jsonResponse.toString().getBytes();
 response.setContentLength(buf.length);
 ServletOutputStream servletOut = response.getOutputStream();
 servletOut.write(buf);
 }
}

This code captures input query string and builds a conformant SOLR query string that is send to SOLR server, it's reponse it's directly returned via result variable to reponse output stream.

Wiki MarkupNow we'll link our new servlet with it's appropriate url, to do so we we'll add this lines in \lines in [dspace-source\]/dspace-jspui/dspace-jspui-webapp/src/main/webapp/WEB-INF/web.xml

Code Block

language	html/xml
title	web.xml
collapse	true

<servlet>
        <servlet-name>searchJSON</servlet-name>
        <servlet-class>org.dspace.app.webui.servlet.SearchJSONServlet</servlet-class>
</servlet>
<servlet-mapping>
        <servlet-name>searchJSON</servlet-name>
        <url-pattern>/searchJSON/*</url-pattern>
</servlet-mapping>

...

Verify that running dspace.cfg contains this configuration line:
Code Block
search.dir = ${dspace.dir}/solr/searchJSPUI/data/index
Wiki Markup
run an index rebuild to populate \ [dspace\]/solr/searchJSPUI/data/index folder with current search indexes (recommended) or copy them directly from \ [dspace\]/search

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Versions Compared

Old Version 29

New Version 30

Key

First steps: Preparing JSPUI advanced search page

Adding javascript functions

Creating a new SOLR core

Creating SearchJSONServlet.java