Xojo Plugin

Azure Service Bus - Unlock Message

See more Azure Service Bus Examples

Shows how to unlock a message for processing by other receivers on a specified queue or subscription. This operation deletes the lock object, causing the message to be unlocked.

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

Xojo Plugin

Dim success As Boolean
success = False

// Note: Requires Chilkat v9.5.0.65 or greater.

// 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.
Dim rest As New Chilkat.Rest
Dim bAutoReconnect As Boolean
bAutoReconnect = True
success = rest.Connect("<yournamespace>.servicebus.windows.net",443,True,bAutoReconnect)
If (success <> True) Then
    System.DebugLog(rest.LastErrorText)
    Return
End If

// 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.
Dim sbToken As New Chilkat.StringBuilder
success = sbToken.LoadFile("qa_data/tokens/serviceBusSas.txt","utf-8")

// Tell the REST object to use the Azure Shared Access Signature for authorization.
success = sbToken.Prepend("SharedAccessSignature ")
success = rest.AddHeader("Authorization",sbToken.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 unlock a message, we'll need either the SequenceNumber or MessageId.
// When the message was 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": 2,
// 	  "EnqueuedSequenceNumber": 3000003,
// 	  "EnqueuedTimeUtc": "Wed, 07 Dec 2016 17:42:48 GMT",
// 	  "Label": "M2",
// 	  "LockToken": "0a13ee8a-be32-4458-89e0-5e1401caa6a0",
// 	  "LockedUntilUtc": "Wed, 07 Dec 2016 18:13:12 GMT",
// 	  "MessageId": "7bea513a6ddb49089e07bfbee26d85bd",
// 	  "SequenceNumber": 3,
// 	  "State": "Active",
// 	  "TimeToLive": 922337203685.47754
// 	}

// 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 unlock a message contained in a subscription.
Dim topicName As String
topicName = "gilaMonster"
Dim subscriptionName As String
subscriptionName = "feedings"
Dim messageId As String
messageId = "7bea513a6ddb49089e07bfbee26d85bd"
Dim lockToken As String
lockToken = "0a13ee8a-be32-4458-89e0-5e1401caa6a0"

// Build the path..
Dim sbPath As New Chilkat.StringBuilder
success = sbPath.Append("/{topicPath}/subscriptions/{subscriptionName}/messages/{messageId|sequenceNumber}/{lockToken}")
Dim numReplaced As Int32
numReplaced = sbPath.Replace("{topicPath}",topicName)
numReplaced = sbPath.Replace("{subscriptionName}",subscriptionName)
numReplaced = sbPath.Replace("{messageId|sequenceNumber}",messageId)
numReplaced = sbPath.Replace("{lockToken}",lockToken)

// Add a timeout parameter.
success = rest.AddQueryParam("timeout","20")

// Use the PUT HTTP verb to unlock the message.
Dim sbResponseBody As New Chilkat.StringBuilder
success = rest.FullRequestNoBodySb("PUT",sbPath.GetAsString(),sbResponseBody)
If (success <> True) Then
    System.DebugLog(rest.LastErrorText)
    Return
End If

System.DebugLog("Response Status Code = " + Str(rest.ResponseStatusCode))

// Check for a success response.
If (rest.ResponseStatusCode <> 200) Then
    System.DebugLog(rest.LastRequestStartLine)
    System.DebugLog(rest.LastRequestHeader)
    System.DebugLog(sbResponseBody.GetAsString())
    System.DebugLog("Failed.")
    Return
End If

// If successful, the response body would be empty..
System.DebugLog("Success.")