Merge pull request #55 from azarc-io/feature/add-context-creation-options

Added MQ Connection Options to allow configuring of connection programatically

Author: matrober-uk

dummy.go

@@ -1,4 +1,5 @@
-// +build ignore+
+//go:build ignore
+// +build ignore
 
 package main
 

go.sum

@@ -1,20 +1,9 @@
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/ibm-messaging/mq-golang v1.0.1-0.20190820103725-19b946c185a8 h1:kUwSXeftVen12FRnShG+Ykhb2Kd6Cd/DbpWwbYal7j0=
-github.com/ibm-messaging/mq-golang v1.0.1-0.20190820103725-19b946c185a8/go.mod h1:qjsZDb7m1oKnbPeDma2JVJTKgyCA91I4bcJ1qHY+gcA=
-github.com/ibm-messaging/mq-golang v3.0.0+incompatible h1:Yc3c8emAyveT54uNDRMkgvS+EBAHeLNWHkc3hk5x+IY=
-github.com/ibm-messaging/mq-golang v3.0.0+incompatible/go.mod h1:qjsZDb7m1oKnbPeDma2JVJTKgyCA91I4bcJ1qHY+gcA=
-github.com/ibm-messaging/mq-golang/v5 v5.0.0 h1:9J8bsDoCo60rbSgB7ZAURPG3L5Kpr+F8dYNOwQ7Qnnk=
-github.com/ibm-messaging/mq-golang/v5 v5.0.0/go.mod h1:ywCwmYbJOU/E0rl+z4GiNoxVMty68O+LVO39a1VMXrE=
-github.com/ibm-messaging/mq-golang/v5 v5.1.2 h1:u0e1Vce2TNqJpH088vF77rDMsnMRWnGaOIlxZo4DMZc=
-github.com/ibm-messaging/mq-golang/v5 v5.1.2/go.mod h1:ywCwmYbJOU/E0rl+z4GiNoxVMty68O+LVO39a1VMXrE=
-github.com/ibm-messaging/mq-golang/v5 v5.1.3 h1:B1Xfk1jMulmDfPf3jH2Dh9nnyEkaqfI1FvTHt4pFza4=
-github.com/ibm-messaging/mq-golang/v5 v5.1.3/go.mod h1:ywCwmYbJOU/E0rl+z4GiNoxVMty68O+LVO39a1VMXrE=
 github.com/ibm-messaging/mq-golang/v5 v5.2.4 h1:Sn+XpnhlTzBs/xPRAHzSx+YjCdxhmzJu5bv4pWTWu/I=
 github.com/ibm-messaging/mq-golang/v5 v5.2.4/go.mod h1:ywCwmYbJOU/E0rl+z4GiNoxVMty68O+LVO39a1VMXrE=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=

jms20subset/ConnectionFactory.go

@@ -18,12 +18,14 @@ type ConnectionFactory interface {
 
 	// CreateContext creates a connection to the messaging provider using the
 	// configuration parameters that are encapsulated by this ConnectionFactory.
+	// Optional options can be provided to configure the connection prior to initialisation.
 	//
 	// Defaults to sessionMode of JMSContextAUTOACKNOWLEDGE
-	CreateContext() (JMSContext, JMSException)
+	CreateContext(opts ...MQOptions) (JMSContext, JMSException)
 
 	// CreateContextWithSessionMode creates a connection to the messaging provider using the
 	// configuration parameters that are encapsulated by this ConnectionFactory,
-	// and the specified session mode.
-	CreateContextWithSessionMode(sessionMode int) (JMSContext, JMSException)
+	// and the specified session mode. Optional options can be provided to configure the
+	// connection prior to initialisation.
+	CreateContextWithSessionMode(sessionMode int, opts ...MQOptions) (JMSContext, JMSException)
 }

jms20subset/MQOptions.go

@@ -0,0 +1,11 @@
+package jms20subset
+
+import "github.com/ibm-messaging/mq-golang/v5/ibmmq"
+
+type MQOptions func(cno *ibmmq.MQCNO)
+
+func WithMaxMsgLength(maxMsgLength int32) MQOptions {
+	return func(cno *ibmmq.MQCNO) {
+		cno.ClientConn.MaxMsgLength = maxMsgLength
+	}
+}

mq_connection_options_test.go

@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) IBM Corporation 2019
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0, which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package main
+
+import (
+	"github.com/ibm-messaging/mq-golang-jms20/jms20subset"
+	"github.com/ibm-messaging/mq-golang/v5/ibmmq"
+	"testing"
+
+	"github.com/ibm-messaging/mq-golang-jms20/mqjms"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMQConnectionOptions(t *testing.T) {
+
+	t.Run("MaxMsgLength set on CreateContext", func(t *testing.T) {
+		// Loads CF parameters from connection_info.json and applicationApiKey.json in the Downloads directory
+		cf, cfErr := mqjms.CreateConnectionFactoryFromDefaultJSONFiles()
+		assert.Nil(t, cfErr)
+
+		// Ensure that the options were applied when setting connection options on Context creation
+		msg := "options were not applied"
+		context, ctxErr := cf.CreateContext(
+			jms20subset.WithMaxMsgLength(2000),
+			func(cno *ibmmq.MQCNO) {
+				assert.Equal(t, int32(2000), cno.ClientConn.MaxMsgLength)
+				msg = "options applied"
+			},
+		)
+		assert.Nil(t, ctxErr)
+
+		if context != nil {
+			defer context.Close()
+		}
+
+		assert.Equal(t, "options applied", msg)
+	})
+
+	t.Run("MaxMsgLength is respected when receive message on CreateContextWithSessionMode", func(t *testing.T) {
+		// Loads CF parameters from connection_info.json and applicationApiKey.json in the Downloads directory
+		cf, cfErr := mqjms.CreateConnectionFactoryFromDefaultJSONFiles()
+		assert.Nil(t, cfErr)
+
+		sContext, ctxErr := cf.CreateContext()
+		assert.Nil(t, ctxErr)
+		if sContext != nil {
+			defer sContext.Close()
+		}
+
+		// Create a Queue object that points at an IBM MQ queue
+		sQueue := sContext.CreateQueue("DEV.QUEUE.1")
+		// Send a message to the queue that contains a large string
+		errSend := sContext.CreateProducer().SendString(sQueue, "This has more than data than the max message length")
+		assert.NoError(t, errSend)
+
+		// create consumer with low msg length
+		rContext, ctxErr := cf.CreateContextWithSessionMode(
+			jms20subset.JMSContextAUTOACKNOWLEDGE,
+			jms20subset.WithMaxMsgLength(20),
+		)
+		assert.Nil(t, ctxErr)
+		if rContext != nil {
+			defer rContext.Close()
+		}
+
+		// Create a Queue object that points at an IBM MQ queue
+		rQueue := rContext.CreateQueue("DEV.QUEUE.1")
+		// Send a message to the queue that contains a large string
+		consumer, errSend := rContext.CreateConsumer(rQueue)
+		assert.NoError(t, errSend)
+
+		// expect that receiving the message will cause an JMS Data Length error
+		_, err := consumer.ReceiveStringBodyNoWait()
+		assert.Error(t, err)
+		jmsErr, ok := err.(jms20subset.JMSExceptionImpl)
+		assert.True(t, ok)
+		assert.Equal(t, "MQRC_DATA_LENGTH_ERROR", jmsErr.GetReason())
+	})
+}

mqjms/ConnectionFactoryImpl.go

@@ -59,13 +59,13 @@ type ConnectionFactoryImpl struct {
 
 // CreateContext implements the JMS method to create a connection to an IBM MQ
 // queue manager.
-func (cf ConnectionFactoryImpl) CreateContext() (jms20subset.JMSContext, jms20subset.JMSException) {
-	return cf.CreateContextWithSessionMode(jms20subset.JMSContextAUTOACKNOWLEDGE)
+func (cf ConnectionFactoryImpl) CreateContext(mqos ...jms20subset.MQOptions) (jms20subset.JMSContext, jms20subset.JMSException) {
+	return cf.CreateContextWithSessionMode(jms20subset.JMSContextAUTOACKNOWLEDGE, mqos...)
 }
 
 // CreateContextWithSessionMode implements the JMS method to create a connection to an IBM MQ
 // queue manager using the specified session mode.
-func (cf ConnectionFactoryImpl) CreateContextWithSessionMode(sessionMode int) (jms20subset.JMSContext, jms20subset.JMSException) {
+func (cf ConnectionFactoryImpl) CreateContextWithSessionMode(sessionMode int, mqos ...jms20subset.MQOptions) (jms20subset.JMSContext, jms20subset.JMSException) {
 
 	// Allocate the internal structures required to create an connection to IBM MQ.
 	cno := ibmmq.NewMQCNO()
@@ -131,6 +131,11 @@ func (cf ConnectionFactoryImpl) CreateContextWithSessionMode(sessionMode int) (j
 
 	}
 
+	// Apply options
+	for _, mqo := range mqos {
+		mqo(cno)
+	}
+
 	var ctx jms20subset.JMSContext
 	var retErr jms20subset.JMSException