Changeset 3799 for trunk/gsdl3/src/java/org/greenstone/gsdl3/service/GS2MGRetrieve.java

Timestamp:

2003-03-05T14:00:32+13:00 (21 years ago)

Author:

mdewsnip

Message:

Modified to inherit from GS2Retrieve.java base class. Only implements search engine specific DocumentContentRetrieve service.

File:

• trunk/gsdl3/src/java/org/greenstone/gsdl3/service/GS2MGRetrieve.java (modified) (4 diffs)

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

@@ -19 +19 @@
 package org.greenstone.gsdl3.service;
 
-// greenstone classes
+
+// 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; 
+// XML classes
+import org.w3c.dom.Element;
 
-// general Java classes
+// General Java classes
 import java.io.File;
-import java.util.HashMap;
+
 
 /**
@@ -43 +38 @@
 
 public class GS2MGRetrieve
-    extends ServiceRack {
+    extends GS2Retrieve {
 
-    // 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
+    // Parameters used
     private static final String INDEX_PARAM = "index";
 
-    // elements used in the config file that are specific to this class
+    // 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;
-    
+
     private String default_index_ = null;
 
 
     /** constructor */
-    public GS2MGRetrieve() {
+    public GS2MGRetrieve()
+    {
+    System.out.println("Constructing GS2MGRetrieve...");
     mg_src_ = new MGWrapper();
-    gdbm_src_ = new GDBMWrapper();
     }
+
 
     /** configure this service */
     public boolean configure(Element info)
     {
-    System.out.println("configuring GS2MGRetrieve");
+    // Do specific configuration
+    System.out.println("Configuring GS2MGRetrieve...");
 
-    // get the default index out of <defaultIndex> (buildConfig.xml)
+    // Get the default index out of <defaultIndex> (buildConfig.xml)
     Element def = (Element) GSXML.getChildByTagName(info, DEFAULT_INDEX_ELEM);
     if (def != null) {
@@ -84 +76 @@
     System.out.println("Default index: " + default_index_);
 
-    Element e = null;
-    // these entries should reflect the build config file - some services may not be available depending on how the colleciton was built.
-    // set up short_service_info_ - for now just has name and type
-    e = doc_.createElement(GSXML.SERVICE_ELEM);
-    e.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_RETRIEVE);
-    e.setAttribute(GSXML.NAME_ATT, DOCUMENT_RETRIEVE_SERVICE);
-    short_service_info_.appendChild(e);
-
-    e = doc_.createElement(GSXML.SERVICE_ELEM);
-    e.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_RETRIEVE);
-    e.setAttribute(GSXML.NAME_ATT, METADATA_RETRIEVE_SERVICE);
-    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.
-    e = doc_.createElement(GSXML.SERVICE_ELEM);
-    e.setAttribute(GSXML.TYPE_ATT, GSXML.SERVICE_TYPE_RETRIEVE);
-    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);
-    e.setAttribute(GSXML.NAME_ATT, METADATA_RETRIEVE_SERVICE);
-    service_info_map_.put(METADATA_RETRIEVE_SERVICE, e);
-
-    // 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);
+    // Do generic configuration
+    return super.configure(info);
     }
 
 
-    /** retrieve a document */
-    protected Element processDocumentRetrieve(Element request)
+    /** Retrieve the structure of a document */
+    protected Element processDocumentStructureRetrieve(Element request)
     {
-    // an empty result
+    return super.processDocumentStructureRetrieve(request);
+    }
+
+
+    /** Retrieve metadata associated with a document */
+    protected Element processDocumentMetadataRetrieve(Element request)
+    {
+    return super.processDocumentMetadataRetrieve(request);
+    }
+
+
+    /** Retrieve the content of a document */
+    protected Element processDocumentContentRetrieve(Element request)
+    {
+    // Create a new (empty) result message
     Element result = doc_.createElement(GSXML.RESPONSE_ELEM);
-    String from = GSPath.appendLink(cluster_name_, DOCUMENT_RETRIEVE_SERVICE);
+    String from = GSPath.appendLink(cluster_name_, DOCUMENT_CONTENT_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);
+    result.setAttribute(GSXML.TYPE_ATT, GSXML.REQUEST_TYPE_PROCESS);
+    Element result_content = doc_.createElement(GSXML.CONTENT_ELEM);
+    result.appendChild(result_content);
 
-    // 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();
+    // Get the parameters of the request
+    Element param_list = (Element) GSXML.getChildByTagName(request, GSXML.PARAM_ELEM+GSXML.LIST_MODIFIER);
+    if (param_list == null) {
+        System.err.println("GS2Retrieve, DocumentContentRetrieve Error: missing paramList.\n");
+        return result;  // Return the empty result
     }
 
-    if (param_elem==null || content_elem==null) {
-        System.err.println("GS2MGRetrieve: malformed request sent to DocumentRetrieve service");
-        return result; // empty result
+    String index = default_index_;
+
+    // Process the request parameters
+    Element param = (Element) param_list.getFirstChild();
+    while (param != null) {
+        if (!param.getNodeName().equals(GSXML.PARAM_ELEM)) {
+        System.err.println("Warning: Non-param in paramList (ignored).");
+        }
+        else {
+        //
+        if (param.getAttribute(GSXML.NAME_ATT) == INDEX_PARAM) {
+            index = GSXML.getValue(param);
+            System.out.println("Index: " + index);
+        }
+        }
+
+        param = (Element) param.getNextSibling();
     }
-    
-    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_;
+    // Get the request content
+    Element content = (Element) GSXML.getChildByTagName(request, GSXML.CONTENT_ELEM);
+    if (content == null) {
+        System.err.println("Error: DocumentContentRetrieve request had no content.\n");
+        return result;
     }
-    System.out.println("Index: " + index);
 
-    String basedir = GSFile.collectionBaseDir(site_home_, cluster_name_) + File.separatorChar;  // Needed by MG
+    Element doc_list = doc_.createElement(GSXML.DOCUMENT_ELEM+GSXML.LIST_MODIFIER);
+    result_content.appendChild(doc_list);
+
+    // The location of the MG index and text files
+    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);
@@ -176 +153 @@
     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);
+    // Get the documents
+    String[] doc_ids = GSXML.getDocumentNameList(content);
+    for (int i = 0; i < doc_ids.length; i++) {
+        String doc_id = doc_ids[i];
+        System.out.println("Retrieving content of " + doc_id + "...");
 
-        result_doc.appendChild(new_doc);
+        long doc_num = gdbm_src_.oid2Docnum(doc_id);
+        String doc_content = mg_src_.getDocument(basedir, textdir, doc_num);
+
+        // For now, stick it in a text node - eventually should be parsed as xml??
+        Element doc = GSXML.createDocumentElement(doc_, doc_id);
+        GSXML.addDocText(doc_, doc, doc_content);
+        doc_list.appendChild(doc);
     }
-    return result;
-    }
 
-
-    /** retrieve metadata */
-    protected Element processMetadataRetrieve(Element request)
-    {
-    Element result = doc_.createElement(GSXML.RESPONSE_ELEM);
-    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;
     }