How can I remove the child node name from the metrics sent to Cloudwatch?

Question

I am working with a Java API built with Ktor. It posts metrics to CloudWatch using the MicrometerMetrics feature. My issue is that I have created an interceptor which is cluttering the route name in CloudWatch.

Here follows the interceptor:

fun Route.test(callback: Route.() -> Unit): Route {
    val routeTest = createChild(object : RouteSelector(1.0) {
        override fun evaluate(context: RoutingResolveContext, segmentIndex: Int): RouteSelectorEvaluation =
            RouteSelectorEvaluation.Constant
    })
    routeTest.intercept(ApplicationCallPipeline.Call) {
        call.response.header("X-Next-Polling-In", pollTime)
    }
    callback(routeTest)
    return routeTest
}

And here is how the route for the request /users, intercepted by the previous interceptor, is shown in CloudWatch:

/users/my.package.TestInterceptor$test$routeTest$1@6cdas3a85

Is there any way to remove the child node name or hardcode an unique value instead of my.package.TestInterceptor$test$routeTest$1@6cdas3a85?

Tudorosu Tudorosu · Accepted Answer · 2021-04-15T09:32:48

I managed to solve this issue by overridding the toString method on the RouteSelector as follows:

fun Route.test(callback: Route.() -> Unit): Route {
    val routeTest = createChild(object : RouteSelector(1.0) {
        override fun evaluate(context: RoutingResolveContext, segmentIndex: Int): RouteSelectorEvaluation =
            RouteSelectorEvaluation.Constant

        override fun toString() = "customName"

    })
    routeTest.intercept(ApplicationCallPipeline.Call) {
        call.response.header("X-Next-Polling-In", pollTime)
    }
    callback(routeTest)
    return routeTest
}

This leads to the following route name:

/users/customName

How can I remove the child node name from the metrics sent to Cloudwatch?

1 Answers