How to run java agent on Corda node by configuring jvm args in gradle build?

Question

I am trying to run a JavaAgent that monitors the code execution on one or multiple Corda nodes so I can track coverage of my functional tests when they are running.

The Corda docs say you can add JVM args by adding this to my node spec:

custom = {
   jvmArgs: [ "-javaAgent:/Path/To/Agent/jacoco-agent.jar=config-file=/Path/To/Agent/jacoco-agent.config",  "-Xmx1G", "-XX:+UseG1GC" ]
}

It seems that I have to add this to each nodes config file but is there a way to add this to all nodes through the build.gradle for example so the agent starts when the node start.

Answer 1

you can edit the node.conf of the generated nodes from the node or nodeDefaults section of the deployNodes task (or any task of type net.corda.plugins.Cordform ) in the build.gradle , so you can simply use

node {
    extraConfig = ['custom.jvmArgs': ["-Xmx1G", "-XX:+UseG1GC"]]
}

note that in Groovy, both lists and dictionaries use square bracket syntax eg

["key" : "value", "key2" : true, "key3" : 42]