Detect string properties that are not set - #39

Author: matrober-uk

jms20subset/Message.go

@@ -48,6 +48,8 @@ type Message interface {
 	// jms20subset.DeliveryMode_PERSISTENT and jms20subset.DeliveryMode_NON_PERSISTENT
 	GetJMSDeliveryMode() int
 
-	SetStringProperty(name string, value string) JMSException
+	SetStringProperty(name string, value *string) JMSException
+
+	// Returns string property, or nil if the property is not set.
 	GetStringProperty(name string) *string
 }

messageproperties_test.go

@@ -56,16 +56,31 @@ func TestStringPropertyTextMsg(t *testing.T) {
 	propValue := "myValue"
 
 	// Test the empty value before the property is set.
-	// TODO - it would be nicer if this was nil rather than empty string, however it
-	//   doesn't look like that is supported by the mq-golang library itself.
-	assert.Equal(t, "", *txtMsg.GetStringProperty(propName))
+	assert.Nil(t, txtMsg.GetStringProperty(propName))
 
 	// Test the ability to set properties before the message is sent.
-	retErr := txtMsg.SetStringProperty(propName, propValue)
+	retErr := txtMsg.SetStringProperty(propName, &propValue)
 	assert.Nil(t, retErr)
 	assert.Equal(t, propValue, *txtMsg.GetStringProperty(propName))
 	assert.Equal(t, msgBody, *txtMsg.GetText())
 
+	// Send an empty string property as well
+	emptyPropName := "myEmptyString"
+	emptyPropValue := ""
+	retErr = txtMsg.SetStringProperty(emptyPropName, &emptyPropValue)
+	assert.Nil(t, retErr)
+	assert.Equal(t, emptyPropValue, *txtMsg.GetStringProperty(emptyPropName))
+
+	// Set a property then try to unset it by setting to nil
+	unsetPropName := "mySendThenRemovedString"
+	unsetPropValue := "someValueThatWillBeOverwritten"
+	retErr = txtMsg.SetStringProperty(unsetPropName, &unsetPropValue)
+	assert.Nil(t, retErr)
+	assert.Equal(t, unsetPropValue, *txtMsg.GetStringProperty(unsetPropName))
+	retErr = txtMsg.SetStringProperty(unsetPropName, nil)
+	assert.Nil(t, retErr)
+	assert.Nil(t, txtMsg.GetStringProperty(unsetPropName))
+
 	// Set up objects for send/receive
 	queue := context.CreateQueue("DEV.QUEUE.1")
 	consumer, errCons := context.CreateConsumer(queue)
@@ -92,6 +107,13 @@ func TestStringPropertyTextMsg(t *testing.T) {
 	// Check property is available on received message.
 	assert.Equal(t, propValue, *rcvMsg.GetStringProperty(propName))
 
+	// Check the empty string property.
+	assert.Equal(t, emptyPropValue, *rcvMsg.GetStringProperty(emptyPropName))
+
+	// Properties that are not set should return nil
+	assert.Nil(t, rcvMsg.GetStringProperty("nonExistentProperty"))
+	assert.Nil(t, rcvMsg.GetStringProperty(unsetPropName))
+
 }
 
 /*
@@ -117,7 +139,7 @@ func TestStringPropertyTextMessageNilBody(t *testing.T) {
 
 	propName := "myProperty2"
 	propValue := "myValue2"
-	retErr := msg.SetStringProperty(propName, propValue)
+	retErr := msg.SetStringProperty(propName, &propValue)
 	assert.Nil(t, retErr)
 
 	// Now send the message and get it back again, to check that it roundtripped.
@@ -172,12 +194,12 @@ func TestStringPropertyTextMessageEmptyBody(t *testing.T) {
 
 	propAName := "myPropertyA"
 	propAValue := "myValueA"
-	retErr := msg.SetStringProperty(propAName, propAValue)
+	retErr := msg.SetStringProperty(propAName, &propAValue)
 	assert.Nil(t, retErr)
 
 	propBName := "myPropertyB"
 	propBValue := "myValueB"
-	retErr = msg.SetStringProperty(propBName, propBValue)
+	retErr = msg.SetStringProperty(propBName, &propBValue)
 	assert.Nil(t, retErr)
 
 	// Now send the message and get it back again.

mqjms/MessageImpl.go

@@ -274,13 +274,26 @@ func (msg *MessageImpl) GetApplName() string {
 	return applName
 }
 
-func (msg *MessageImpl) SetStringProperty(name string, value string) jms20subset.JMSException {
+func (msg *MessageImpl) SetStringProperty(name string, value *string) jms20subset.JMSException {
 	var retErr jms20subset.JMSException
 
-	smpo := ibmmq.NewMQSMPO()
-	pd := ibmmq.NewMQPD()
+	var linkedErr error
+
+	if value != nil {
+		// Looking to set a value
+		var valueStr string
+		valueStr = *value
+
+		smpo := ibmmq.NewMQSMPO()
+		pd := ibmmq.NewMQPD()
 
-	linkedErr := msg.msgHandle.SetMP(smpo, name, pd, value)
+		linkedErr = msg.msgHandle.SetMP(smpo, name, pd, valueStr)
+	} else {
+		// Looking to unset a value
+		dmpo := ibmmq.NewMQDMPO()
+
+		linkedErr = msg.msgHandle.DltMP(dmpo, name)
+	}
 
 	if linkedErr != nil {
 		rcInt := int(linkedErr.(*ibmmq.MQReturn).MQRC)
@@ -298,13 +311,59 @@ func (msg *MessageImpl) GetStringProperty(name string) *string {
 	impo := ibmmq.NewMQIMPO()
 	pd := ibmmq.NewMQPD()
 
-	_, value, _ := msg.msgHandle.InqMP(impo, pd, name)
+	_, value, err := msg.msgHandle.InqMP(impo, pd, name)
 
-	switch valueTyped := value.(type) {
-	case string:
-		valueStr = valueTyped
-	default:
-		// TODO - other conversions
+	if err == nil {
+		switch valueTyped := value.(type) {
+		case string:
+			valueStr = valueTyped
+		default:
+			// TODO - other conversions
+		}
+	} else {
+
+		mqret := err.(*ibmmq.MQReturn)
+		if mqret.MQRC == ibmmq.MQRC_PROPERTY_NOT_AVAILABLE {
+			// This indicates that the requested property does not exist.
+			// valueStr will remain with its default value of nil
+			return nil
+		} else {
+			// Err was not nil
+			fmt.Println(err) // TODO - finish error handling
+		}
 	}
 	return &valueStr
 }
+
+func (msg *MessageImpl) propertyExists(name string) bool {
+
+	impo := ibmmq.NewMQIMPO()
+	pd := ibmmq.NewMQPD()
+
+	impo.Options = ibmmq.MQIMPO_CONVERT_VALUE | ibmmq.MQIMPO_INQ_FIRST
+	for propsToRead := true; propsToRead; {
+
+		gotName, gotValue, err := msg.msgHandle.InqMP(impo, pd, "%")
+		impo.Options = ibmmq.MQIMPO_CONVERT_VALUE | ibmmq.MQIMPO_INQ_NEXT
+		if err != nil {
+			mqret := err.(*ibmmq.MQReturn)
+			if mqret.MQRC != ibmmq.MQRC_PROPERTY_NOT_AVAILABLE {
+				fmt.Println(err)
+			} else {
+				// Read all properties
+				return false
+			}
+
+			propsToRead = false
+		} else if gotName == name {
+			// Found the matching property name (shortcut)
+			return true
+		} else {
+			fmt.Printf("no property match to '%s' - gotName: '%s' gotValue '%v' \n", name, gotName, gotValue)
+		}
+
+	}
+
+	// Went through all properties and didn't find a match
+	return false
+}