Amazon offers ElasticSearch Cloud service. As you may know, Amazon is based on a fork called Opendistro after some issues with the original product. This Amazon product has its own lifecycle with versioning tags different from the original ElasticSearch product. So when it comes to test your Java client code against server to check integration, it’s not easy to come up with a valid environment that closely simulates what is happening with the actual Amazon product.

So, this article is offering a working example on how to do integration testing for your Java clients as part of your project build…

I guess this article will come in handy for those writing one of these templates for the first time. You will find plenty of documentation about Apache VTL , and some examples. But those are pretty basic. So this article is focused on a particular use case where we need to transform a generic response including JSON body into XML.

var mappingTemplate = require('api-gateway-mapping-template')

var vtl = `
#set($cdrMap = $input.path('$'))
#set($accountSidPos = $context.resourcePath.indexOf('{AccountSid}') + 13)
#set($sidPos = $context.resourcePath.indexOf('{Sid}') - 2)
#set($cdrXmlRoot = $context.resourcePath.substring($accountSidPos, $sidPos))
#foreach($cdrFieldKey in $cdrMap.keySet())
#set($cdrField = $cdrMap.get($cdrFieldKey))…


Performance testing has been traditionally relegated to latest software phases. Even Agile approaches fail to define clearly how to approach this time consuming activity, as teams fails to incorporate performance conditions in their DefinitionOfDone. In Telestax we strive to get best performance from our software, and durings latest year we have progressed on incorporating this activity in our ContinousDelivery strategy.

The problem

Performance testing is hard to achieve right. Both controlling the runtime environment, and how to collect the data to provide stable and comparable results is hard enough. …

Jaime Casero

Software Engineer with more than 15 years experience in the Telco sector. Currently working at Telestax.

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