How does one configure VSTS specific load test context parameters for own azure agents intelligently - performance

Question

Recently moved from utilising AWS to Azure for the location of our load test agents, thus making the transition to making full use of VSTS.
It was described that, for the moment, to get a load test file working with VSTS to using our own VMs for testing, we need to provide two context parameters, UseStaticLoadAgents and StaticAgentsGroupName in each loadtest file.
Our load test solution is getting very large, and we have multiple loadtest files where we have to set these two values each time. This leads us into the situation where, if we were to change our agents group name for example, we would have to update each individual load test file with the new information.
Im looking at a way to centralise this until a nicer way is implemented by Microsoft. The idea was to use a load test plugin, to add these context parameters with the plugin drawing the needed values from a centralised config file.
However, it seems that none of the hooks in the load test plugin or simply using the initialise method to manually set these values is working. Likely because they are set after full initialisation.
Has anyone got a nice, code focused solution to manage this and stop us depending on adding brittle values in the editor? Or even gotten the above approach to work?

Answer 1

The loadtest file is the XML file, so you can update it programmatically, for example:
string filePath = #"XXX\LoadTest1.loadtest";
XmlDocument doc = new XmlDocument();
doc.Load(filePath);
XmlNamespaceManager nsmgr = new XmlNamespaceManager(doc.NameTable);
nsmgr.AddNamespace("ns", "http://microsoft.com/schemas/VisualStudio/TeamTest/2010");
XmlNode root = doc.DocumentElement;
XmlNode nodeParameters = root.SelectSingleNode("//ns:RunConfigurations/ns:RunConfiguration[#Name='Run Settings1']/ns:ContextParameters", nsmgr);
if(nodeParameters!=null)
{
//nodeParameters.SelectSingleNode("//ns:ContextParameter[#Name='UseStaticLoadAgents']").Value = "agent1";
foreach (XmlNode n in nodeParameters.ChildNodes)
{
switch (n.Attributes["Name"].Value)
{
case "Parameter1":
n.Attributes["Value"].Value = "testUpdate";
break;
case "UseStaticLoadAgents":
n.Attributes["Value"].Value = "agent1";
break;
case "StaticAgentsGroupName":
n.Attributes["Value"].Value = "group1";
break;
}
}
}
doc.Save(filePath);