问题
How to subscribe a IBM MQ topic from .net client in a subscriber model
I have already a working copy of the code which is able to get message from the topic.
string qmName = "Q1";
string hostName = "MyHost";
string strPort = "1114";
string channelName = "MyCh";
string transport = TRP;
Hashtable connectionProperties = new Hashtable();
connectionProperties.Add(MQC.HOST_NAME_PROPERTY, hostName);
connectionProperties.Add(MQC.PORT_PROPERTY, strPort);
connectionProperties.Add(MQC.CHANNEL_PROPERTY, channelName);
MQQueueManager mqQueueManager = new MQQueueManager(qmName, connectionProperties);
string topicString = "TTTT";
string subscriptionName = "SSS";
int openOptionsForGet = MQC.MQSO_FAIL_IF_QUIESCING | MQC.MQSO_DURABLE | MQC.MQSO_RESUME;
MQTopic destForGet = mqQueueManager.AccessTopic(null, null, null, openOptionsForGet, null, subscriptionName);
MQMessage messageForGet = new MQMessage();
MQGetMessageOptions gmo = new MQGetMessageOptions();
gmo.Options |= MQC.MQGMO_WAIT | MQC.MQGMO_FAIL_IF_QUIESCING;
gmo.WaitInterval = 3000; // wait 60 seconds
destForGet.Get(messageForGet, gmo);
string msg = messageForGet.ReadLine();
System.Console.WriteLine("Received message data : " + msg);
MessageBox.Show("Received message data : " + msg);
destForGet.Close();
mqQueueManager.Disconnect();
mqQueueManager.Close();
so above code is always opening and closing the connection however I want to make a connection and subscription to call in a loop/sleep time interval so every time no connection is made and closed. So requirement is:
Make connection for one time and then topic subscription is on every 1 minutes to read the data and process.
As of now whenever message is read it's being removed from topic. I want to know how to commit/ack to remove the queue message post successful processing.
I don't want to get the msg removed from the queue.
回答1:
Make connection for one time and then topic subscription is on every 1 minutes to read the data and process.
Just use a while loop (that's not an MQ issue). Also, why do you want to wait 1 minute? With Pub/Sub or even point-to-point messaging, messages could be building while your application sleeps.
As of now whenever message is read it's being removed from topic. I want to know how to commit/ack to remove the queue message post successful processing.
You can use a syncpoint but then you need to either commit or backout the message.
I don't want to get the msg removed from the queue.
Why are you using Pub/Sub? Wouldn't it be better to use point-to-point messaging? i.e. browse rather than get.
MQC.MQSO_DURABLE | MQC.MQSO_RESUME;
I would strongly suggest you read the MQ Knowledge Center and understand what these options do. Because there is a world of difference between durable and non-durable.
Here is a fully functioning C# .NET MQ program running in managed-mode to get messages from a topic string:
using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using IBM.WMQ;
/// <summary> Program Name
/// MQTest82
///
/// Description
/// This C# class will connect to a remote queue manager
/// and get messages from a topic using a managed .NET environment.
///
/// Sample Command Line Parameters
/// -h 127.0.0.1 -p 1415 -c TEST.CHL -m MQWT1 -t ABC/XYZ -u tester -x mypwd
/// </summary>
/// <author> Roger Lacroix
/// </author>
namespace MQTest82
{
public class MQTest82
{
private Hashtable inParms = null;
private Hashtable qMgrProp = null;
private System.String qManager;
private System.String topicString;
/*
* The constructor
*/
public MQTest82()
: base()
{
}
/// <summary> Make sure the required parameters are present.</summary>
/// <returns> true/false
/// </returns>
private bool allParamsPresent()
{
bool b = inParms.ContainsKey("-h") && inParms.ContainsKey("-p") &&
inParms.ContainsKey("-c") && inParms.ContainsKey("-m") &&
inParms.ContainsKey("-t");
if (b)
{
try
{
System.Int32.Parse((System.String)inParms["-p"]);
}
catch (System.FormatException e)
{
b = false;
}
}
return b;
}
/// <summary> Extract the command-line parameters and initialize the MQ variables.</summary>
/// <param name="args">
/// </param>
/// <throws> IllegalArgumentException </throws>
private void init(System.String[] args)
{
inParms = System.Collections.Hashtable.Synchronized(new System.Collections.Hashtable(14));
if (args.Length > 0 && (args.Length % 2) == 0)
{
for (int i = 0; i < args.Length; i += 2)
{
inParms[args[i]] = args[i + 1];
}
}
else
{
throw new System.ArgumentException();
}
if (allParamsPresent())
{
qManager = ((System.String)inParms["-m"]);
topicString = ((System.String)inParms["-t"]);
qMgrProp = new Hashtable();
qMgrProp.Add(MQC.TRANSPORT_PROPERTY, MQC.TRANSPORT_MQSERIES_MANAGED);
qMgrProp.Add(MQC.HOST_NAME_PROPERTY, ((System.String)inParms["-h"]));
qMgrProp.Add(MQC.CHANNEL_PROPERTY, ((System.String)inParms["-c"]));
try
{
qMgrProp.Add(MQC.PORT_PROPERTY, System.Int32.Parse((System.String)inParms["-p"]));
}
catch (System.FormatException e)
{
qMgrProp.Add(MQC.PORT_PROPERTY, 1414);
}
if (inParms.ContainsKey("-u"))
qMgrProp.Add(MQC.USER_ID_PROPERTY, ((System.String)inParms["-u"]));
if (inParms.ContainsKey("-x"))
qMgrProp.Add(MQC.PASSWORD_PROPERTY, ((System.String)inParms["-x"]));
logger("Parameters:");
logger(" QMgrName ='" + qManager + "'");
logger(" Topic String ='" + topicString + "'");
logger("QMgr Property values:");
foreach (DictionaryEntry de in qMgrProp)
{
logger(" " + de.Key + " = '" + de.Value + "'");
}
}
else
{
throw new System.ArgumentException();
}
}
/// <summary> Connect, open topic, get messages, close topic and disconnect. </summary>
///
private void testReceive()
{
MQQueueManager qMgr = null;
MQTopic inTopic = null;
int openOptionsForGet = MQC.MQSO_CREATE | MQC.MQSO_FAIL_IF_QUIESCING | MQC.MQSO_MANAGED | MQC.MQSO_NON_DURABLE;
try
{
qMgr = new MQQueueManager(qManager, qMgrProp);
logger("successfully connected to " + qManager);
inTopic = qMgr.AccessTopic(topicString, null, MQC.MQTOPIC_OPEN_AS_SUBSCRIPTION, openOptionsForGet);
logger("successfully opened " + topicString);
testLoop(inTopic);
}
catch (MQException mqex)
{
logger("CC=" + mqex.CompletionCode + " : RC=" + mqex.ReasonCode);
}
catch (System.IO.IOException ioex)
{
logger("ioex=" + ioex);
}
finally
{
try
{
if (inTopic != null)
inTopic.Close();
logger("closed: " + topicString);
}
catch (MQException mqex)
{
logger("CC=" + mqex.CompletionCode + " : RC=" + mqex.ReasonCode);
}
try
{
if (qMgr != null)
qMgr.Disconnect();
logger("disconnected from " + qManager);
}
catch (MQException mqex)
{
logger("CC=" + mqex.CompletionCode + " : RC=" + mqex.ReasonCode);
}
}
}
private void testLoop(MQTopic inTopic)
{
bool flag = true;
MQGetMessageOptions gmo = new MQGetMessageOptions();
gmo.Options |= MQC.MQGMO_NO_WAIT | MQC.MQGMO_FAIL_IF_QUIESCING;
MQMessage msg = null;
while (flag)
{
try
{
msg = new MQMessage();
inTopic.Get(msg, gmo);
if (msg.Feedback == MQC.MQFB_QUIT)
{
flag = false;
logger("received quit message - exiting loop");
}
else
logger("Message Data: " + msg.ReadString(msg.MessageLength));
}
catch (MQException mqex)
{
logger("CC=" + mqex.CompletionCode + " : RC=" + mqex.ReasonCode);
if (mqex.Reason == MQC.MQRC_NO_MSG_AVAILABLE)
{
// no meesage - life is good - loop again
logger("sleeping");
Thread.Sleep(60*1000); // sleep for 60 seconds
}
else
{
flag = false; // severe error - time to exit
}
}
catch (System.IO.IOException ioex)
{
logger("ioex=" + ioex);
}
}
}
private void logger(String data)
{
DateTime myDateTime = DateTime.Now;
System.Console.Out.WriteLine(myDateTime.ToString("yyyy/MM/dd HH:mm:ss.fff") + " " + this.GetType().Name + ": " + data);
}
/// <summary> main line</summary>
/// <param name="args">
/// </param>
// [STAThread]
public static void Main(System.String[] args)
{
MQTest82 write = new MQTest82();
try
{
write.init(args);
write.testReceive();
}
catch (System.ArgumentException e)
{
System.Console.Out.WriteLine("Usage: MQTest82 -h host -p port -c channel -m QueueManagerName -t topicString [-u userID] [-x passwd]");
System.Environment.Exit(1);
}
catch (MQException e)
{
System.Console.Out.WriteLine(e);
System.Environment.Exit(1);
}
System.Environment.Exit(0);
}
}
}
来源：https://stackoverflow.com/questions/56883199/subscribing-to-a-ibm-mq-topic-from-a-net-client