Visual FoxPro

Azure Service Bus - Delete Message

See more Azure Service Bus Examples

Deletes a message from a queue or subscription.

For more information, see https://docs.microsoft.com/en-us/rest/api/servicebus/unlock-message

Visual FoxPro

LOCAL lnSuccess
LOCAL loRest
LOCAL lnBAutoReconnect
LOCAL loSbToken
LOCAL lcTopicName
LOCAL lcSubscriptionName
LOCAL lcMessageId
LOCAL lcLockToken
LOCAL loSbPath
LOCAL lnNumReplaced
LOCAL loSbResponseBody

lnSuccess = 0

* This requires the Chilkat API to have been previously unlocked.
* See Global Unlock Sample for sample code.

* Make the initial connection.
* A single REST object, once connected, can be used for many Azure Service Bus REST API calls.
* The auto-reconnect indicates that if the already-established HTTPS connection is closed,
* then it will be automatically re-established as needed.
loRest = CreateObject('Chilkat.Rest')
lnBAutoReconnect = 1
lnSuccess = loRest.Connect("<yournamespace>.servicebus.windows.net",443,1,lnBAutoReconnect)
IF (lnSuccess <> 1) THEN
    ? loRest.LastErrorText
    RELEASE loRest
    CANCEL
ENDIF

* Let's load a previously computed SAS token and use it.
* See Azure Shared Access Signature for an example to genenerate an Azure SAS token.
loSbToken = CreateObject('Chilkat.StringBuilder')
loSbToken.LoadFile("qa_data/tokens/serviceBusSas.txt","utf-8")

* Tell the REST object to use the Azure Shared Access Signature for authorization.
loSbToken.Prepend("SharedAccessSignature ")
loRest.AddHeader("Authorization",loSbToken.GetAsString())

* ----------------------------------------------------------------------------------------------
* The code above this comment could be placed inside a function/subroutine within the application
* because the connection does not need to be made for every request.  Once the connection is made
* the app may send many requests..
* ----------------------------------------------------------------------------------------------

* To delete a message, we'll need either the SequenceNumber or MessageId.
* When the message was peek-locked, the SequenceNumber and MessageId of the locked message
* was returned in the HTTP response header named "BrokerProperties, which contained
* JSON such as the following:
* 
* 	{
* 	  "DeliveryCount": 1,
* 	  "EnqueuedSequenceNumber": 3000004,
* 	  "EnqueuedTimeUtc": "Wed, 07 Dec 2016 17:42:48 GMT",
* 	  "Label": "M3",
* 	  "LockToken": "6eeee205-e541-4cb6-95fb-4c81da5f6858",
* 	  "LockedUntilUtc": "Thu, 08 Dec 2016 00:57:32 GMT",
* 	  "MessageId": "e8028116d63c43f191577f2789b1cca7",
* 	  "SequenceNumber": 4,
* 	  "State": "Active",
* 	  "TimeToLive": 922337193600
* 	}
* 
* 
* The path for unlocking a message is constructed as follows, depending on
* whether it is a message on a queue or subscription:
* 
* (for a queue)
* /{queuePath}/messages/{messageId|sequenceNumber}/{lockToken}
* 
* (for a subscription)
* /{topicPath}/subscriptions/{subscriptionName}/messages/{messageId|sequenceNumber}/{lockToken}

* This example will build a path to delete a message contained in a subscription.
lcTopicName = "gilaMonster"
lcSubscriptionName = "feedings"
lcMessageId = "e8028116d63c43f191577f2789b1cca7"
lcLockToken = "6eeee205-e541-4cb6-95fb-4c81da5f6858"

* Build the path..
loSbPath = CreateObject('Chilkat.StringBuilder')
loSbPath.Append("/{topicPath}/subscriptions/{subscriptionName}/messages/{messageId|sequenceNumber}/{lockToken}")
lnNumReplaced = loSbPath.Replace("{topicPath}",lcTopicName)
lnNumReplaced = loSbPath.Replace("{subscriptionName}",lcSubscriptionName)
lnNumReplaced = loSbPath.Replace("{messageId|sequenceNumber}",lcMessageId)
lnNumReplaced = loSbPath.Replace("{lockToken}",lcLockToken)

* Add a timeout parameter.
loRest.AddQueryParam("timeout","20")

* Use the DELETE HTTP verb to delete the message.
loSbResponseBody = CreateObject('Chilkat.StringBuilder')
lnSuccess = loRest.FullRequestNoBodySb("DELETE",loSbPath.GetAsString(),loSbResponseBody)
IF (lnSuccess <> 1) THEN
    ? loRest.LastErrorText
    RELEASE loRest
    RELEASE loSbToken
    RELEASE loSbPath
    RELEASE loSbResponseBody
    CANCEL
ENDIF

? "Response Status Code = " + STR(loRest.ResponseStatusCode)

* Check for a success response.
IF (loRest.ResponseStatusCode <> 200) THEN
    ? loRest.LastRequestStartLine
    ? loRest.LastRequestHeader
    ? loSbResponseBody.GetAsString()
    ? "Failed."
    RELEASE loRest
    RELEASE loSbToken
    RELEASE loSbPath
    RELEASE loSbResponseBody
    CANCEL
ENDIF

* If successful, the response body would be empty..
? "Success."

RELEASE loRest
RELEASE loSbToken
RELEASE loSbPath
RELEASE loSbResponseBody