Adding Session Canceling, DISCOVER_SESSIONS, and DISCOVER_COMMANDS.

src/main/java/mondrian/xmla/XmlaConstants.java

@@ -44,6 +44,8 @@ public interface XmlaConstants {
     public static final String NS_SQL = "urn:schemas-microsoft-com:xml-sql";
     public static final String NS_XMLA_EX =
         "urn:schemas-microsoft-com:xml-analysis:exception";
+    public static final String NS_XMLA_MS_EXTENSIONS =
+        "http://schemas.microsoft.com/analysisservices/2003/engine";
 
     public static final String NS_SOAP_SECEXT =
         "http://schemas.xmlsoap.org/ws/2002/04/secext";

src/main/java/mondrian/xmla/XmlaHandler.java

@@ -693,6 +693,10 @@ private void execute(
         XmlaResponse response)
         throws XmlaException
     {
+        if (request.isCancel()) {
+            cancelSession(request);
+            return;
+        }
         final Map<String, String> properties = request.getProperties();
 
         // Default responseMimeType is SOAP.
@@ -1318,6 +1322,32 @@ static void writeEmptyDatasetXmlSchema(SaxWriter writer, SetType setType) {
         writer.endElement(); // xsd:schema
     }
 
+    private void cancelSession(XmlaRequest request) throws XmlaException {
+        String sessionId = request.getStatement();
+        if (!authorizeSessionCancel(sessionId, request)) {
+            throw new XmlaException(
+                CLIENT_FAULT_FC,
+                CHH_AUTHORIZATION_CODE,
+                CHH_AUTHORIZATION_FAULT_FS,
+                Util.newInternal(
+                    "Unauthorized request to cancel session " + sessionId));
+        }
+        XmlaSessionManager.getInstance().cancelSession(sessionId);
+    }
+
+    protected boolean authorizeSessionCancel(
+        String sessionId,
+        XmlaRequest request)
+    {
+        String[] credentials =
+            XmlaSessionManager.getInstance().getSessionCredentials(sessionId);
+        if (credentials == null || credentials.length == 0 || credentials[0] == null) {
+            return true;
+        }
+        return credentials[0].equals(request.getUsername()) && (
+            credentials[1] == null || credentials[1].equals(request.getPassword()));
+    }
+
     private QueryResult executeDrillThroughQuery(XmlaRequest request)
         throws XmlaException
     {
@@ -1336,16 +1366,19 @@ private QueryResult executeDrillThroughQuery(XmlaRequest request)
         OlapStatement statement = null;
         ResultSet resultSet = null;
         try {
+            String mdx = request.getStatement();
             connection =
                 getConnection(request, Collections.<String, String>emptyMap());
             statement = connection.createStatement();
+            XmlaSessionManager.getInstance().addStatementToSession(
+                request.getSessionId(), statement, mdx);
             final XmlaHandler.XmlaExtra extra = connectionFactory.getExtra();
             final boolean enableRowCount = extra.isTotalCountEnabled();
             final int[] rowCountSlot = enableRowCount ? new int[]{0} : null;
             resultSet =
                 extra.executeDrillthrough(
                     statement,
-                    request.getStatement(),
+                    mdx,
                     advanced,
                     tabFields,
                     rowCountSlot);
@@ -1375,6 +1408,8 @@ private QueryResult executeDrillThroughQuery(XmlaRequest request)
                 }
             }
             if (statement != null) {
+                XmlaSessionManager.getInstance().removeStatementFromSession(
+                    request.getSessionId(), statement);
                 try {
                     statement.close();
                 } catch (SQLException e) {
@@ -1658,6 +1693,8 @@ private QueryResult executeQuery(XmlaRequest request)
             extra.setPreferList(connection);
             try {
                 statement = connection.prepareOlapStatement(mdx);
+                XmlaSessionManager.getInstance().addStatementToSession(
+                    request.getSessionId(), statement, mdx);
             } catch (XmlaException ex) {
                 throw ex;
             } catch (Exception ex) {
@@ -1699,6 +1736,10 @@ private QueryResult executeQuery(XmlaRequest request)
                     ex);
             }
         } finally {
+            if (statement != null) {
+                XmlaSessionManager.getInstance().removeStatementFromSession(
+                    request.getSessionId(), statement);
+            }
             if (!success) {
                 if (cellSet != null) {
                     try {

src/main/java/mondrian/xmla/XmlaRequest.java

@@ -59,6 +59,11 @@ public interface XmlaRequest {
      */
     boolean isDrillThrough();
 
+    /**
+     * Indicate whether EXECUTE method is a session cancel.
+     */
+    boolean isCancel();
+
     /**
      * The username to use to open the underlying olap4j connection.
      * Can be null.

src/main/java/mondrian/xmla/XmlaServlet.java

@@ -16,6 +16,7 @@
 
 import java.io.IOException;
 import java.io.UnsupportedEncodingException;
+import java.sql.SQLException;
 import java.util.*;
 import javax.servlet.ServletConfig;
 import javax.servlet.ServletException;
@@ -38,9 +39,11 @@ public abstract class XmlaServlet
         "OptionalDataSourceConfig";
     public static final String PARAM_CHAR_ENCODING = "CharacterEncoding";
     public static final String PARAM_CALLBACKS = "Callbacks";
+    public static final String PARAM_CANCEL_SQL_STATE = "CancelSqlState";
 
     protected XmlaHandler xmlaHandler = null;
     protected String charEncoding = null;
+    protected final HashSet<String> cancelSqlStateSet = new HashSet<String>();
     private final List<XmlaRequestCallback> callbackList =
         new ArrayList<XmlaRequestCallback>();
 
@@ -95,6 +98,8 @@ public void init(ServletConfig servletConfig)
         // init: callbacks
         initCallbacks(servletConfig);
 
+        initCancelSqlState(servletConfig);
+
         this.connectionFactory = createConnectionFactory(servletConfig);
     }
 
@@ -133,6 +138,21 @@ protected final List<XmlaRequestCallback> getCallbacks() {
         return Collections.unmodifiableList(callbackList);
     }
 
+    private boolean isCancelException(Throwable t) {
+        if (cancelSqlStateSet == null || cancelSqlStateSet.isEmpty()) {
+            return false;
+        }
+
+        if (t instanceof SQLException) {
+            String sqlState = ((SQLException) t).getSQLState();
+            return cancelSqlStateSet.contains(sqlState);
+        } else if (t.getCause() != null) {
+            return isCancelException(t.getCause());
+        } else {
+            return false;
+        }
+    }
+
     /**
      * Main entry for HTTP post method
      *
@@ -320,7 +340,11 @@ protected void doPost(
                     responseSoapParts,
                     context);
             } catch (XmlaException xex) {
-                LOGGER.error("Errors when handling XML/A message", xex);
+                if (isCancelException(xex)) {
+                    LOGGER.info("XML/A request canceled", xex);
+                } else {
+                    LOGGER.error("Errors when handling XML/A message", xex);
+                }
                 handleFault(response, responseSoapParts, phase, xex);
                 phase = Phase.SEND_ERROR;
                 marshallSoapMessage(response, responseSoapParts, mimeType);
@@ -441,6 +465,22 @@ protected void initCharEncodingHandler(ServletConfig servletConfig) {
         }
     }
 
+    /**
+     * Initialize possible cancel sql states
+     */
+    protected void initCancelSqlState(ServletConfig servletConfig) {
+        String paramValue = servletConfig.getInitParameter(
+            PARAM_CANCEL_SQL_STATE);
+        if (paramValue != null) {
+            for (String sqlState : paramValue.split(",")) {
+                sqlState = sqlState.trim();
+                if (sqlState.length() > 0) {
+                    cancelSqlStateSet.add(sqlState);
+                }
+            }
+        }
+    }
+
     /**
      * Registers callbacks configured in web.xml.
      */