B4X

Azure Service Bus - Receive and Delete Message from Subscription

See more Azure Service Bus Examples

Shows how to receive and delete a message from an Azure service bus topic subscription. B4X

Dim success As Boolean = 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 ChilkatRest
rest.Initialize("rest")
Dim bAutoReconnect As Boolean = True
success = rest.Connect("<yournamespace>.servicebus.windows.net", 443, True, bAutoReconnect)
If success <> True Then
    Log(rest.LastErrorText)
    Return
End If


'  ----------------------------------------------------------------------------------------------
'  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..
'  ----------------------------------------------------------------------------------------------

'  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 ChilkatStringBuilder
sbToken.Initialize
sbToken.LoadFile("qa_data/tokens/serviceBusSas.txt", "utf-8")

'  Tell the REST object to use the Azure Shared Access Signature for authorization.
sbToken.Prepend("SharedAccessSignature ")
rest.AddHeader("Authorization", sbToken.GetAsString)

'  ----------------------------------------------------------------------------------------------

'  Receive a message from the subscription "feedings" in the topic "gilaMonster"
Dim topicName As String = "gilaMonster"
Dim subscriptionName As String = "feedings"

'  Build the path..
Dim sbPath As ChilkatStringBuilder
sbPath.Initialize
sbPath.Append("/")
sbPath.Append(topicName)
sbPath.Append("/subscriptions/")
sbPath.Append(subscriptionName)
sbPath.Append("/messages/head")

'  Add a timeout parameter.
rest.AddQueryParam("timeout", "20")

'  Use the DELETE HTTP verb to read the message at the head of the queue and remove it.
Dim sbResponseBody As ChilkatStringBuilder
sbResponseBody.Initialize
success = rest.FullRequestNoBodySb("DELETE", sbPath.GetAsString, sbResponseBody)
If success <> True Then
    Log(rest.LastErrorText)
    Return
End If


Log("Response Status Code = " & rest.ResponseStatusCode)

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


'  If successful, the message is the contents of the response body.
Dim message As String = sbResponseBody.GetAsString
Log("Received message: " & message)

Log("Success.")