(Tcl) 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.

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load ./chilkat.dll

# 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.
set rest [new_CkRest]

set bAutoReconnect 1
set success [CkRest_Connect $rest "<yournamespace>.servicebus.windows.net" 443 1 $bAutoReconnect]
if {$success != 1} then {
    puts [CkRest_lastErrorText $rest]
    delete_CkRest $rest
    exit
}

# ----------------------------------------------------------------------------------------------
# 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.
set sbToken [new_CkStringBuilder]

CkStringBuilder_LoadFile $sbToken "qa_data/tokens/serviceBusSas.txt" "utf-8"

# Tell the REST object to use the Azure Shared Access Signature for authorization.
CkStringBuilder_Prepend $sbToken "SharedAccessSignature "
CkRest_AddHeader $rest "Authorization" [CkStringBuilder_getAsString $sbToken]

# ----------------------------------------------------------------------------------------------

# Receive a message from the subscription "feedings" in the topic "gilaMonster"
set topicName "gilaMonster"
set subscriptionName "feedings"

# Build the path..
set sbPath [new_CkStringBuilder]

CkStringBuilder_Append $sbPath "/"
CkStringBuilder_Append $sbPath $topicName
CkStringBuilder_Append $sbPath "/subscriptions/"
CkStringBuilder_Append $sbPath $subscriptionName
CkStringBuilder_Append $sbPath "/messages/head"

# Add a timeout parameter.
CkRest_AddQueryParam $rest "timeout" "20"

# Use the DELETE HTTP verb to read the message at the head of the queue and remove it.
set sbResponseBody [new_CkStringBuilder]

set success [CkRest_FullRequestNoBodySb $rest "DELETE" [CkStringBuilder_getAsString $sbPath] $sbResponseBody]
if {$success != 1} then {
    puts [CkRest_lastErrorText $rest]
    delete_CkRest $rest
    delete_CkStringBuilder $sbToken
    delete_CkStringBuilder $sbPath
    delete_CkStringBuilder $sbResponseBody
    exit
}

puts "Response Status Code = [CkRest_get_ResponseStatusCode $rest]"

# Check for a success response.
if {[CkRest_get_ResponseStatusCode $rest] != 200} then {
    puts [CkRest_lastRequestStartLine $rest]
    puts [CkRest_lastRequestHeader $rest]
    puts [CkStringBuilder_getAsString $sbResponseBody]
    puts "Failed."
    delete_CkRest $rest
    delete_CkStringBuilder $sbToken
    delete_CkStringBuilder $sbPath
    delete_CkStringBuilder $sbResponseBody
    exit
}

# If successful, the message is the contents of the response body.
set message [CkStringBuilder_getAsString $sbResponseBody]
puts "Received message: $message"

puts "Success."

delete_CkRest $rest
delete_CkStringBuilder $sbToken
delete_CkStringBuilder $sbPath
delete_CkStringBuilder $sbResponseBody