Changeset 3754

Timestamp:

2003-02-21T11:47:07+13:00 (21 years ago)

Author:

mdewsnip

Message:

Alpha version of service for document retrieval using MG.

File:

• trunk/gsdl3/src/java/org/greenstone/gsdl3/service/GS2MGRetrieve.java (modified) (5 diffs)

trunk/gsdl3/src/java/org/greenstone/gsdl3/service/GS2MGRetrieve.java

@@ -19 +19 @@
 package org.greenstone.gsdl3.service;
 
+// greenstone classes
+import org.greenstone.mg.*;
+import org.greenstone.gdbm.*;
 import org.greenstone.gsdl3.util.*;
 
+// xml classes
+import org.w3c.dom.CDATASection;
 import org.w3c.dom.Document; 
+import org.w3c.dom.Element; 
 import org.w3c.dom.Node; 
+import org.w3c.dom.NodeList; 
 import org.w3c.dom.Text; 
-import org.w3c.dom.Element; 
-import org.w3c.dom.NodeList; 
+
+// general Java classes
+import java.io.File;
+import java.util.HashMap;
+
 /**
  *
@@ -36 +46 @@
 
     // the services on offer
+    // these strings must match what is found in the properties file
     private static final String DOCUMENT_RETRIEVE_SERVICE = "DocumentRetrieve";
     private static final String METADATA_RETRIEVE_SERVICE = "MetadataRetrieve";
+
+    // params used
+    private static final String INDEX_PARAM = "index";
+
+    // elements used in the config file that are specific to this class
+    private static final String DEFAULT_INDEX_ELEM = "defaultIndex";
+
+    private MGWrapper mg_src_ = null;
+    private GDBMWrapper gdbm_src_ = null;
     
-
-    /** creates a display element containing all the text strings needed to display the service page, in the language specified */
-    protected Element createServiceDisplay(String service, String lang) {
-    Element display = doc_.createElement(GSXML.DISPLAY_ELEM);
-    display.appendChild(GSXML.createTextElement(doc_, GSXML.DISPLAY_NAME_ELEM,  getTextString(service+".name", lang)));
-    display.appendChild(GSXML.createTextElement(doc_,  GSXML.DISPLAY_SUBMIT_ELEM, getTextString(service+".submit", lang)));
-
-    Element param;
-
-    return display;
-    
-    }
-
+    private String default_index_ = null;
+
+
+    /** constructor */
+    public GS2MGRetrieve() {
+    mg_src_ = new MGWrapper();
+    gdbm_src_ = new GDBMWrapper();
+    }
 
     /** configure this service */
-    public boolean configure(Element info) {
-
+    public boolean configure(Element info)
+    {
     System.out.println("configuring GS2MGRetrieve");
+
+    // get the default index out of <defaultIndex> (buildConfig.xml)
+    Element def = (Element) GSXML.getChildByTagName(info, DEFAULT_INDEX_ELEM);
+    if (def != null) {
+        default_index_ = def.getAttribute(GSXML.NAME_ATT);
+    }
+    if (default_index_ == null || default_index_.equals("")) {
+        System.err.println("Error: default index not specified!");
+        return false;
+    }
+    System.out.println("Default index: " + default_index_);
 
     Element e = null;
@@ -71 +97 @@
     short_service_info_.appendChild(e);
 
-
     // set up service_info_map_ - for now, just has the same elements as above
     // should have full details about each service incl params lists etc.
@@ -78 +103 @@
     e.setAttribute(GSXML.NAME_ATT, DOCUMENT_RETRIEVE_SERVICE);
     service_info_map_.put(DOCUMENT_RETRIEVE_SERVICE, e);
-    
+
     e = doc_.createElement(GSXML.SERVICE_ELEM);
     e.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_RETRIEVE);
@@ -84 +109 @@
     service_info_map_.put(METADATA_RETRIEVE_SERVICE, e);
 
-    return true;
-    }
-  /** retrieve a document */
-    protected Element processDocumentRetrieve(Element request) {
+    // Open GDBM database for querying
+    String gdbm_db_file = GSFile.GDBMDatabaseFile(site_home_, cluster_name_);
+    if (gdbm_src_.openDatabase(gdbm_db_file, GDBMWrapper.READER)) {
+        return true;
+    }
+    else {
+        System.err.println("Error: Could not open gdbm database!");
+        return false;
+    }
+    }
+
+    /** creates a display element containing all the text strings needed to display the service page, in the language specified 
+     * these retrieval services dont get displayed to the users - they are only used internally by the actions. so this returns an empty display element*/
+    protected Element createServiceDisplay(String service, String lang)
+    {
+    return doc_.createElement(GSXML.DISPLAY_ELEM);
+    }
+
+
+    /** retrieve a document */
+    protected Element processDocumentRetrieve(Element request)
+    {
+    // an empty result
     Element result = doc_.createElement(GSXML.RESPONSE_ELEM);
-    result.setAttribute(GSXML.NAME_ATT, DOCUMENT_RETRIEVE_SERVICE);
+    String from = GSPath.appendLink(cluster_name_, DOCUMENT_RETRIEVE_SERVICE);
+    result.setAttribute(GSXML.FROM_ATT, from);
+    result.setAttribute(GSXML.TYPE_ATT, GSXML.REQUEST_TYPE_QUERY);
+    Element result_doc = doc_.createElement(GSXML.CONTENT_ELEM);
+    result.appendChild(result_doc);
+
+    // get param list and content 
+    Element param_elem = null;
+    Element content_elem = null;
+    Node n = request.getFirstChild();
+    while (n != null) {
+        String node_name = n.getNodeName();
+        if (node_name.equals(GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER)) {
+        param_elem = (Element) n;
+        } else if (node_name.equals(GSXML.CONTENT_ELEM)) {
+        content_elem = (Element) n;
+        }
+        n = n.getNextSibling();
+    }
+
+    if (param_elem==null || content_elem==null) {
+        System.err.println("GS2MGRetrieve: malformed request sent to DocumentRetrieve service");
+        return result; // empty result
+    }
     
-    // dummy result
-    Text t = null;
-    t = doc_.createTextNode(DOCUMENT_RETRIEVE_SERVICE+" result... ");
-    result.appendChild(t);
+    HashMap params = GSXML.extractParams(param_elem);
+
+    // get docs from mg
+    String index = (String) params.get(INDEX_PARAM); 
+    if (index == null) { // if it is not present, use the default index
+        index = default_index_;
+    }
+    System.out.println("Index: " + index);
+
+    String basedir = GSFile.collectionBaseDir(site_home_, cluster_name_) + File.separatorChar;  // Needed by MG
+    String textdir = GSFile.collectionTextPath(cluster_name_);
+    String indexpath = GSFile.collectionIndexPath(cluster_name_, index);
+    System.out.println("Base directory: " + basedir);
+    System.out.println("Text directory: " + textdir);
+    System.out.println("Index path: " + indexpath);
+
+    mg_src_.setIndex(indexpath);
+
+    // get the text for each doc in the list
+    String[] ids = GSXML.getDocumentNameList(content_elem);
+    for (int j=0; j<ids.length; j++) {
+        long real_num = gdbm_src_.oid2Docnum(ids[j]);
+        String document = mg_src_.getDocument(basedir, textdir, real_num);
+        System.out.println("(MGRetrieve) Document: " + document);
+        // for now, stick it in a text node - eventually should be parsed as xml??
+        // something funny with the doc - 
+        Element new_doc = GSXML.createDocumentElement(doc_, ids[j]);
+        GSXML.addDocText(doc_, new_doc, document);
+
+        result_doc.appendChild(new_doc);
+    }
     return result;
     }
 
-  /** retrieve metadata */
-    protected Element processMetadataRetrieve(Element request) {
+
+    /** retrieve metadata */
+    protected Element processMetadataRetrieve(Element request)
+    {
     Element result = doc_.createElement(GSXML.RESPONSE_ELEM);
-    result.setAttribute(GSXML.NAME_ATT, METADATA_RETRIEVE_SERVICE);
-    
-    // dummy result
-    Text t = null;
-    t = doc_.createTextNode(METADATA_RETRIEVE_SERVICE+" result... ");
-    result.appendChild(t);
+    String from = GSPath.appendLink(cluster_name_, METADATA_RETRIEVE_SERVICE);
+    result.setAttribute(GSXML.FROM_ATT, from);
+    result.setAttribute(GSXML.TYPE_ATT, GSXML.REQUEST_TYPE_QUERY);
+
+    Element result_content = doc_.createElement(GSXML.CONTENT_ELEM);
+    result.appendChild(result_content);
+    Element document_list = doc_.createElement(GSXML.DOCUMENT_ELEM+GSXML.LIST_MODIFIER);
+    result_content.appendChild(document_list);
+
+    // get the metadata
+        Element content = (Element) request.getElementsByTagName(GSXML.CONTENT_ELEM).item(0);
+    if (content == null) {
+        // error: query had no content!! - should make an error message
+        return result;
+    }
+    String[] metas = GSXML.getMetaNameList(content);
+    String[] ids = GSXML.getDocumentNameList(content);
+    for (int j = 0; j < ids.length; j++) { // for each document
+        Element doc = GSXML.createDocumentElement(doc_, ids[j]);
+        Element list = GSXML.addMetaList(doc_, doc);
+        DBInfo info = gdbm_src_.getInfo(ids[j]);
+        for (int m = 0; m < metas.length; m++) {
+        String value = info.getInfo(metas[m]);
+        GSXML.addMetadata(doc_, list, metas[m], value);
+        }
+        document_list.appendChild(doc);
+    }
     return result;
     }
-
 }