Proposal: add DoNotFulfillResendRequest exception to allow applications to prevent resend

quickfixj-core/src/main/java/quickfix/Application.java

@@ -79,7 +79,7 @@ public interface Application {
      * @throws RejectLogon causes a logon reject
      */
     void fromAdmin(Message message, SessionID sessionId) throws FieldNotFound, IncorrectDataFormat,
-            IncorrectTagValue, RejectLogon;
+            IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest;
 
     /**
      * This is a callback for application messages that you are sending to a

quickfixj-core/src/main/java/quickfix/DoNotFulfillResendRequest.java

@@ -0,0 +1,42 @@
+/*******************************************************************************
+ * Copyright (c) quickfixengine.org  All rights reserved.
+ *
+ * This file is part of the QuickFIX FIX Engine
+ *
+ * This file may be distributed under the terms of the quickfixengine.org
+ * license as defined by quickfixengine.org and appearing in the file
+ * LICENSE included in the packaging of this file.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING
+ * THE WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A
+ * PARTICULAR PURPOSE.
+ *
+ * See http://www.quickfixengine.org/LICENSE for licensing information.
+ *
+ * Contact [email protected] if any conditions of this licensing
+ * are not clear to you.
+ ******************************************************************************/
+
+package quickfix;
+
+/**
+ * Applications can throw this exception to abort the fulfillment of an
+ * incoming ResendRequest.
+ *
+ * Example use case: the counterparty sends an excessive number of
+ * ResendRequests in error, and we want to prevent quickfix from fulfilling
+ * them, spiking cpu and disk I/O, overwhelming the server.  Further action,
+ * such as sending Rejects to alert the counterparty to the problem, are left
+ * up to Applications.
+ */
+public class DoNotFulfillResendRequest extends Exception {
+    private final static String defaultMsg = "Fulfillment of ResendRequest aborted by Application";
+
+    public DoNotFulfillResendRequest() {
+        super(defaultMsg);
+    }
+
+    public DoNotFulfillResendRequest(String msg) {
+        super(defaultMsg + ": " + msg);
+    }
+}

quickfixj-core/src/main/java/quickfix/Session.java

@@ -1856,7 +1856,17 @@ private boolean verify(Message msg, boolean checkTooHigh, boolean checkTooLow)
             return false;
         }
 
-        fromCallback(msgType, msg, sessionID);
+        try {
+            fromCallback(msgType, msg, sessionID);
+        }  catch (final DoNotFulfillResendRequest e) {
+            getLog().onErrorEvent(e.getClass().getName() + ": " + e.getMessage());
+            // Only increment seqnum if we are at the expected seqnum
+            if (getExpectedTargetNum() == msg.getHeader().getInt(MsgSeqNum.FIELD)) {
+                state.incrNextTargetMsgSeqNum();
+            }
+            return false;
+        }
+
         return true;
     }
 
@@ -1904,7 +1914,7 @@ private boolean isGoodTime(Message message) throws FieldNotFound {
 
     private void fromCallback(String msgType, Message msg, SessionID sessionID2)
             throws RejectLogon, FieldNotFound, IncorrectDataFormat, IncorrectTagValue,
-            UnsupportedMessageType {
+            UnsupportedMessageType, DoNotFulfillResendRequest {
         // Application exceptions will prevent the incoming sequence number from being incremented
         // and may result in resend requests and the next startup. This way, a buggy application
         // can be fixed and then reprocess previously sent messages.

quickfixj-core/src/test/java/quickfix/SessionTest.java

@@ -1137,7 +1137,7 @@ public void testRejectLogon() throws Exception {
             @Override
             public void fromAdmin(Message message, SessionID sessionId)
                     throws FieldNotFound, IncorrectDataFormat,
-                    IncorrectTagValue, RejectLogon {
+                    IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 throw new RejectLogon("FOR TEST");
             }
@@ -1176,7 +1176,7 @@ public void testRejectLogonWithSessionStatus() throws Exception {
             @Override
             public void fromAdmin(Message message, SessionID sessionId)
                     throws FieldNotFound, IncorrectDataFormat,
-                    IncorrectTagValue, RejectLogon {
+                    IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 throw new RejectLogon("FOR TEST", SessionStatus.SESSION_ACTIVE);
             }
@@ -1192,7 +1192,7 @@ public void fromAdmin(Message message, SessionID sessionId)
             @Override
             public void fromAdmin(Message message, SessionID sessionId)
                     throws FieldNotFound, IncorrectDataFormat,
-                    IncorrectTagValue, RejectLogon {
+                    IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 throw new RejectLogon("FOR TEST", -1);
             }
@@ -1266,7 +1266,7 @@ public void fromApp(Message message, SessionID sessionId)
             @Override
             public void fromAdmin(Message message, SessionID sessionId)
                     throws FieldNotFound, IncorrectDataFormat,
-                    IncorrectTagValue, RejectLogon {
+                    IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 if (message.getHeader().getString(MsgType.FIELD)
                         .equals(MsgType.LOGON)) {
@@ -1757,7 +1757,7 @@ public void testCatchErrorsFromCallbackAndSendReject() throws Exception {
             @Override
             public void fromAdmin(Message message, SessionID sessionId)
                     throws FieldNotFound, IncorrectDataFormat,
-                    IncorrectTagValue, RejectLogon {
+                    IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 final String msgType = message.getHeader().getString(
                         MsgType.FIELD);
@@ -2460,7 +2460,7 @@ public void testResendSeqWithReject() throws Exception {
 
             @Override
             public void fromAdmin(Message message, SessionID sessionId) throws FieldNotFound,
-                    IncorrectDataFormat, IncorrectTagValue, RejectLogon {
+                    IncorrectDataFormat, IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 if (message.getHeader().getString(MsgType.FIELD).equals(Logon.MSGTYPE)) {
                     logonCount += 1;
@@ -2772,7 +2772,7 @@ public void msgseqnum_getting_reset_in_rejected_logon_scenario_fix() throws Exce
             int logonCount = 0;
             @Override
             public void fromAdmin(Message message, SessionID sessionId) throws FieldNotFound,
-                    IncorrectDataFormat, IncorrectTagValue, RejectLogon {
+                    IncorrectDataFormat, IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 if (message.getHeader().getString(MsgType.FIELD).equals(Logon.MSGTYPE)) {
                     logonCount += 1;
@@ -3145,4 +3145,45 @@ public void testSend_ShouldKeepPossDupFlagAndOrigSendingTime_GivenAllowPosDupCon
         assertTrue(sentMessage.getHeader().isSetField(PossDupFlag.FIELD));
         assertTrue(sentMessage.getHeader().isSetField(OrigSendingTime.FIELD));
     }
+
+    @Test
+    public void testDoNotFulfillResendRequest() throws Exception {
+        // Given an application that does not fulfill ResendRequests
+        final UnitTestApplication application = new UnitTestApplication() {
+            @Override
+            public void fromAdmin(quickfix.Message message, SessionID sessionID) throws FieldNotFound, IncorrectDataFormat, IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
+                 if ("2".contentEquals(message.getHeader().getString(35))) {
+                    throw new DoNotFulfillResendRequest("No resend for you!");
+                 }
+            }
+        };
+
+        // And the session is logged on
+        final SessionID sessionID = new SessionID(FixVersions.BEGINSTRING_FIX44, "SENDER", "TARGET");
+        Session session = SessionFactoryTestSupport.createSession(sessionID, application, false, false, true, true, null);
+        UnitTestResponder responder = new UnitTestResponder();
+        session.setResponder(responder);
+        final SessionState state = getSessionState(session);
+        logonTo(session, 1);
+        assertEquals(2, state.getNextTargetMsgSeqNum());
+        assertEquals(true, session.isLoggedOn());
+
+        // And the following app-level messages have been sent
+        session.send(createAppMessage(2));
+        session.send(createAppMessage(3));
+        session.send(createAppMessage(4));
+        assertEquals(3, application.toAppMessages.size());
+
+        // When the counterparty requests resend
+        Message incomingResendRequest = createResendRequest(2, 1);
+        incomingResendRequest.toString(); // calculate length/checksum
+        processMessage(session, incomingResendRequest);
+
+        // Then no messages should be resent
+        assertEquals(3, application.toAppMessages.size());
+
+        // And the session should remain logged on
+        assertEquals(true, session.isLoggedOn());
+        session.close();
+    }
 }

quickfixj-core/src/test/java/quickfix/UnitTestApplication.java

@@ -59,7 +59,7 @@ public void toApp(Message message, SessionID sessionId) throws DoNotSend {
 
     @Override
     public void fromAdmin(Message message, SessionID sessionId) throws FieldNotFound,
-            IncorrectDataFormat, IncorrectTagValue, RejectLogon {
+            IncorrectDataFormat, IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
         log.info("from admin [{}] {}", sessionId, message);
         fromAdminMessages.add(message);
     }

quickfixj-core/src/test/java/quickfix/mina/ThreadPerSessionEventHandlingStrategyTest.java

@@ -31,6 +31,7 @@
 import quickfix.MemoryStoreFactory;
 import quickfix.Message;
 import quickfix.RejectLogon;
+import quickfix.DoNotFulfillResendRequest;
 import quickfix.Responder;
 import quickfix.SLF4JLogFactory;
 import quickfix.Session;
@@ -116,7 +117,7 @@ public void testEventHandling() throws Exception {
         final UnitTestApplication application = new UnitTestApplication() {
             @Override
             public void fromAdmin(Message message, SessionID sessionId) throws FieldNotFound,
-                    IncorrectDataFormat, IncorrectTagValue, RejectLogon {
+                    IncorrectDataFormat, IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 latch.countDown();
             }
@@ -185,7 +186,7 @@ public void testEventHandlingOnDisconnect() throws Exception {
         final UnitTestApplication application = new UnitTestApplication() {
             @Override
             public void fromAdmin(Message message, SessionID sessionId) throws FieldNotFound,
-                    IncorrectDataFormat, IncorrectTagValue, RejectLogon {
+                    IncorrectDataFormat, IncorrectTagValue, RejectLogon, DoNotFulfillResendRequest {
                 super.fromAdmin(message, sessionId);
                 latch.countDown();
             }