Does api gateway transformation support xml functions like util.parseXml?

Question

Hi,

We have a soap service which takes xml request. We want to make json request available for our clients. The idea is that the clients sends json request to api gateway and then we will transform(using vtl scripting) the request to xml and send it so our web service(soap) and then do the same when we receive the response.

The issue we are having is, it seems like functions like "util.parseXml" is not working . Although aws does specify that it works when using it in AWS App Sync  but i could not find any documentation that shows it works in api gateway.

Thanks

Answer

To transform JSON requests to XML for your SOAP service using API Gateway, you can use VTL scripts in the integration request and response templates.

In the integration request template, use the 
util.parseJson()
 function to parse the JSON body and store it as a variable:

#set($input = $util.parseJson($input.body))
Then use 
util.toXml()
 to convert the JSON to XML:

$util.toXml($input)
In the integration response template, parse the XML response body and convert it back to JSON:

#set($input = $util.parseXml($input.body))
$util.toJson($input)
You may need to define mappings between JSON and XML properties as needed.

The VTL functions like 
util.parseJson()
 and 
util.toXml()
 work in API Gateway for transforming request and response payloads between formats.

Does api gateway transformation support xml functions like util.parseXml?

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