Xbase++

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. Xbase++

LOCAL nSuccess
LOCAL oRest
LOCAL nBAutoReconnect
LOCAL oSbToken
LOCAL cTopicName
LOCAL cSubscriptionName
LOCAL oSbPath
LOCAL oSbResponseBody
LOCAL cMessage

nSuccess := 0

//  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.
oRest := CreateObject("Chilkat.Rest")
nBAutoReconnect := 1
nSuccess := oRest:Connect("<yournamespace>.servicebus.windows.net", 443, 1, nBAutoReconnect)
IF (nSuccess != 1)
    ? oRest:LastErrorText
    oRest:destroy()
    RETURN
ENDIF

//  ----------------------------------------------------------------------------------------------
//  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.
oSbToken := CreateObject("Chilkat.StringBuilder")
oSbToken:LoadFile("qa_data/tokens/serviceBusSas.txt", "utf-8")

//  Tell the REST object to use the Azure Shared Access Signature for authorization.
oSbToken:Prepend("SharedAccessSignature ")
oRest:AddHeader("Authorization", oSbToken:GetAsString())

//  ----------------------------------------------------------------------------------------------

//  Receive a message from the subscription "feedings" in the topic "gilaMonster"
cTopicName := "gilaMonster"
cSubscriptionName := "feedings"

//  Build the path..
oSbPath := CreateObject("Chilkat.StringBuilder")
oSbPath:Append("/")
oSbPath:Append(cTopicName)
oSbPath:Append("/subscriptions/")
oSbPath:Append(cSubscriptionName)
oSbPath:Append("/messages/head")

//  Add a timeout parameter.
oRest:AddQueryParam("timeout", "20")

//  Use the DELETE HTTP verb to read the message at the head of the queue and remove it.
oSbResponseBody := CreateObject("Chilkat.StringBuilder")
nSuccess := oRest:FullRequestNoBodySb("DELETE", oSbPath:GetAsString(), oSbResponseBody)
IF (nSuccess != 1)
    ? oRest:LastErrorText
    oRest:destroy()
    oSbToken:destroy()
    oSbPath:destroy()
    oSbResponseBody:destroy()
    RETURN
ENDIF

? "Response Status Code = " + Str(oRest:ResponseStatusCode)

//  Check for a success response.
IF (oRest:ResponseStatusCode != 200)
    ? oRest:LastRequestStartLine
    ? oRest:LastRequestHeader
    ? oSbResponseBody:GetAsString()
    ? "Failed."
    oRest:destroy()
    oSbToken:destroy()
    oSbPath:destroy()
    oSbResponseBody:destroy()
    RETURN
ENDIF

//  If successful, the message is the contents of the response body.
cMessage := oSbResponseBody:GetAsString()
? "Received message: " + cMessage

? "Success."

oRest:destroy()
oSbToken:destroy()
oSbPath:destroy()
oSbResponseBody:destroy()