Changeset 28852 for main/trunk/greenstone3/src/java/org/greenstone/gsdl3/OAIServer.java

Timestamp:

2014-02-27T11:37:20+13:00 (10 years ago)

Author:

kjdon

Message:

Got rid of this.document. DOM not thread safe, so now we must create a new Document each time we are generating a message. A little bit of tidying up too.

File:

• main/trunk/greenstone3/src/java/org/greenstone/gsdl3/OAIServer.java (modified) (19 diffs)

main/trunk/greenstone3/src/java/org/greenstone/gsdl3/OAIServer.java

@@ -27 +27 @@
 import javax.servlet.ServletConfig;
 import javax.servlet.ServletException;
+import javax.servlet.UnavailableException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
@@ -75 +76 @@
 
     /**
-     * a converter class to parse XML and create Docs This is only used for
-     * generating internal requests passed to MessageRouter. The response
-     * message is generated by parsing an existing xml skeleton file
-     * (web/WEB-INF/oaixml/oaiversion2.xml, for example).
+     * a converter class to parse XML and create Documents for 
+     * XML generation
      */
     protected XMLConverter converter = null;
-    /**
-     * container Document to create XML Nodes (but only request to the oai
-     * receptionist, not response (which is created in OAIXML.java) created by
-     * converter class
-     */
-    protected Document doc = null;
 
     /** A HashSet which contains all the legal verbs. */
@@ -101 +94 @@
     protected String site = "";
 
+  // can be overriddden in OAIConfig.xml
     // do we output the stylesheet processing instruction?
     protected boolean use_oai_stylesheet = true;
@@ -136 +130 @@
             if (remote_site_name == null || remote_site_type == null || remote_site_address == null)
             {
-                System.err.println("initialisation paramters not all set!");
-                System.err.println("if site_name is not set, then you must have remote_site_name, remote_site_type and remote_site_address set");
-                System.exit(1);
+                logger.error("initialisation paramters not all set!");
+                logger.error("if site_name is not set, then you must have remote_site_name, remote_site_type and remote_site_address set");
+                throw new UnavailableException("OAIServer: incorrect servlet parameters");
             }
         }
@@ -150 +144 @@
         // the receptionist -the servlet will talk to this
         this.recept = new OAIReceptionist();
-
+        // the converter - used to get new Documents to generate XML messages
+        this.converter = new XMLConverter();
         // the receptionist uses a MessageRouter or Communicator to send its requests to. We either create a MessageRouter here for the designated site (if site_name set), or we create a Communicator for a remote site. The is given to teh Receptionist, and the servlet never talks to it again.directly.
         if (site_name != null)
@@ -169 +164 @@
                 catch (Exception e)
                 { // cant use this new one, so use normal one
-                    System.err.println("OAIServlet configure exception when trying to use a new MessageRouter " + mr_name + ": " + e.getMessage());
-                    e.printStackTrace();
-                    message_router = new MessageRouter();
+                  logger.error("OAIServlet configure exception when trying to use a new MessageRouter " + mr_name, e);
+                  message_router = new MessageRouter();
                 }
             }
@@ -177 +171 @@
             message_router.setSiteName(site_name);
             // lots of work is done in this step; see MessageRouter.java
-            message_router.configure();
+            if (!message_router.configure()) {
+              throw new UnavailableException("OAIServer: Couldn't configure MessageRouter");
+            }
             this.recept.setSiteName(site_name);
             this.recept.setMessageRouter(message_router);
@@ -187 +183 @@
             Communicator communicator = null;
             // we need to create the XML to configure the communicator
-            Element site_elem = this.doc.createElement(GSXML.SITE_ELEM);
+            Document site_doc = this.converter.newDOM();
+            Element site_elem = site_doc.createElement(GSXML.SITE_ELEM);
             site_elem.setAttribute(GSXML.TYPE_ATT, remote_site_type);
             site_elem.setAttribute(GSXML.NAME_ATT, remote_site_name);
@@ -198 +195 @@
             else
             {
-                System.err.println("OAIServlet.init Error: invalid Communicator type: " + remote_site_type);
-                System.exit(1);
+                logger.error("OAIServlet.init Error: invalid Communicator type: " + remote_site_type);
+                throw new UnavailableException("OAIServer: invalid communicator type");
             }
 
             if (!communicator.configure(site_elem))
             {
-                System.err.println("OAIServlet.init Error: Couldn't configure communicator");
-                System.exit(1);
+                logger.error("OAIServlet.init Error: Couldn't configure communicator");
+                throw new UnavailableException("OAIServer: Couldn't configure communicator");
             }
             this.recept.setSiteName(remote_site_name);
             this.recept.setMessageRouter(communicator);
         }
-        // used for composing internal xml requests, but not xml responses.
-        // the converter may be used to get pretty xml, though.    
-        this.converter = new XMLConverter();
-        this.doc = this.converter.newDOM();
 
         // Read in OAIConfig.xml (residing web/WEB-INF/classes/) and 
-        //use it to configure the receptionist. The init() is also called in which
-        //the resumption token file is read in and all expired tokens cleared.
+        //use it to configure the receptionist. 
         Element oai_config = OAIXML.getOAIConfigXML();
         if (oai_config == null)
         {
             logger.error("Fail to parse oai config file OAIConfig.xml.");
-            return;
+            throw new UnavailableException("OAIServer: Couldn't parse OAIConfig.xml");
         }
         // pass it to the receptionist
-        this.recept.configure(oai_config);
-
+        if (!this.recept.configure(oai_config)) {
+          logger.error("Couldn't configure receptionist");
+          throw new UnavailableException("OAIServer: Couldn't configure receptionist"); 
+        }
         // also, we have something we want to get from here - useOAIStylesheet
         this.configure(oai_config);
+        // Initialise the resumption tokens
+        OAIResumptionToken.init();
+
     }//end of init()
 
@@ -331 +328 @@
     {
         logUsageInfo(request);
-        //out.println("url="+request.getRequestURL());// /oaiserver    
-        //out.println("query="+request.getQueryString());// is /greenstone3
 
         // oai always requires the content type be text/xml
@@ -355 +350 @@
         String[] pairs = (query == null) ? null : query.split("&");//split into key/value pairs
         String verb = getVerb(query);
-        Element xml_response = OAIXML.createBasicResponse(verb, pairs);
+        Document response_doc = this.converter.newDOM();
+        Element xml_response = OAIXML.createBasicResponse(response_doc, verb, pairs);
         Element verb_elem = null;
 
@@ -363 +359 @@
             {
                 logger.error(OAIXML.BAD_VERB + ": " + query);
-                verb_elem = OAIXML.createErrorElement(OAIXML.BAD_VERB, OAIXML.ILLEGAL_OAI_VERB);
+                verb_elem = OAIXML.createErrorElement(response_doc, OAIXML.BAD_VERB, OAIXML.ILLEGAL_OAI_VERB);
             }
             else
@@ -369 +365 @@
                 //must be something else other than bad verbs caused an error, so bad argument
                 logger.error(OAIXML.BAD_ARGUMENT + ": " + query);
-                verb_elem = OAIXML.createErrorElement(OAIXML.BAD_ARGUMENT, "");
+                verb_elem = OAIXML.createErrorElement(response_doc, OAIXML.BAD_ARGUMENT, "");
             }
             xml_response.appendChild(verb_elem);
@@ -384 +380 @@
         // The query is valid, we can now
         // compose the request message to the receptionist
-        Element xml_message = this.doc.createElement(GSXML.MESSAGE_ELEM);
-        Element xml_request = this.doc.createElement(GSXML.REQUEST_ELEM);
+        Document request_doc = this.converter.newDOM();
+        Element xml_message = request_doc.createElement(GSXML.MESSAGE_ELEM);
+        Element xml_request = request_doc.createElement(GSXML.REQUEST_ELEM);
         // The type attribute is set to be 'oaiService' from OAIServer to OAIReceptionist.
         //xml_request.setAttribute(GSXML.TYPE_ATT, OAIXML.OAI_SERVICE);
@@ -399 +396 @@
         {
             logger.info("xml_result is null");
-            verb_elem = OAIXML.createErrorElement("Internal error", "");
+            verb_elem = OAIXML.createErrorElement(response_doc, "Internal error", "");
             xml_response.appendChild(verb_elem);
         }
@@ -410 +407 @@
              * is optional! </resumptionToken> </verb> </response> </message>
              */
-            Node res = GSXML.getChildByTagName(xml_result, OAIXML.RESPONSE);
+            Node res = GSXML.getChildByTagName(xml_result, GSXML.RESPONSE_ELEM);
             if (res == null)
             {
                 logger.info("response element in xml_result is null");
-                verb_elem = OAIXML.createErrorElement("Internal error", "");
+                verb_elem = OAIXML.createErrorElement(response_doc, "Internal error", "");
             }
             else
@@ -421 +418 @@
             }
 
-            if (OAIXML.oai_version.equals(OAIXML.OAI_VERSION2) || verb_elem.getTagName().equals(OAIXML.ERROR))
-            {
-                xml_response.appendChild(xml_response.getOwnerDocument().importNode(verb_elem, true));
+            if ( verb_elem.getTagName().equals(OAIXML.ERROR))
+            {
+              xml_response.appendChild(response_doc.importNode(verb_elem, true));
+            }
+            else if (OAIXML.oai_version.equals(OAIXML.OAI_VERSION2)) {
+              xml_response.appendChild(response_doc.importNode(verb_elem, true));
             }
             else
@@ -442 +442 @@
     public void addParams(Element request, String[] pairs)
     {
+      Document doc = request.getOwnerDocument();
         // no params apart from the verb
         if (pairs == null || pairs.length < 2)
@@ -456 +457 @@
             if (index != -1)
             { //just a double check
-                Element param = this.doc.createElement(OAIXML.PARAM);
-                param.setAttribute(OAIXML.NAME, pairs[i].substring(0, index));
-                param.setAttribute(OAIXML.VALUE, OAIXML.oaiDecode(pairs[i].substring(index + 1)));
-                request.appendChild(param);
+              Element param = GSXML.createParameter(doc, pairs[i].substring(0, index), OAIXML.oaiDecode(pairs[i].substring(index + 1)));
+              request.appendChild(param);
             }
         }