harness: Improve OpenDC Experiment Harness (v1)

This pull request contains several improvements to the OpenDC Experiment Harness, 
which aims to improve user-experience of users when re-running experiments in the repository.

*  Split the harness into separate modules
*  Add support for adding additional classpath entries when running experiments via the console
*  Initial support for configuration of experiments using HOCON.

3 files changed, 15 insertions, 12 deletions

diff --git a/opendc-experiments/opendc-experiments-serverless20/build.gradle.kts b/opendc-experiments/opendc-experiments-serverless20/build.gradle.kts
index 40b15af4..f19d6067 100644
--- a/opendc-experiments/opendc-experiments-serverless20/build.gradle.kts
+++ b/opendc-experiments/opendc-experiments-serverless20/build.gradle.kts
@@ -31,12 +31,13 @@ plugins {
 
 dependencies {
     api(platform(project(":opendc-platform")))
-    api(project(":opendc-harness"))
+    api(project(":opendc-harness:opendc-harness-engine"))
     implementation(project(":opendc-serverless:opendc-serverless-service"))
     implementation(project(":opendc-serverless:opendc-serverless-simulator"))
     implementation(project(":opendc-telemetry:opendc-telemetry-sdk"))
-
+    implementation(project(":opendc-harness:opendc-harness-cli"))
     implementation("io.github.microutils:kotlin-logging")
+    implementation("com.typesafe:config")
 
     implementation("org.apache.parquet:parquet-avro:${versions["parquet-avro"]}")
     implementation("org.apache.hadoop:hadoop-client:${versions["hadoop-client"]}") {
diff --git a/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt b/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt
index 67b5ea54..3ff01e39 100644
--- a/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt
+++ b/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt
@@ -22,9 +22,9 @@
 
 package org.opendc.experiments.serverless
 
+import com.typesafe.config.ConfigFactory
 import io.opentelemetry.api.metrics.MeterProvider
 import io.opentelemetry.sdk.metrics.SdkMeterProvider
-import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.coroutineScope
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
@@ -59,14 +59,9 @@ public class ServerlessExperiment : Experiment("Serverless") {
     private val logger = KotlinLogging.logger {}
 
     /**
-     * The path to where the traces are located.
+     * The configuration to use.
      */
-    private val tracePath by anyOf(File("../../input/traces/serverless"))
-
-    /**
-     * The path to where the output results should be written.
-     */
-    private val outputPath by anyOf(File("output/"))
+    private val config = ConfigFactory.load().getConfig("opendc.experiments.serverless20")
 
     /**
      * The routing policy to test.
@@ -78,14 +73,13 @@ public class ServerlessExperiment : Experiment("Serverless") {
      */
     private val coldStartModel by anyOf(ColdStartModel.LAMBDA, ColdStartModel.AZURE, ColdStartModel.GOOGLE)
 
-    @OptIn(ExperimentalCoroutinesApi::class)
     override fun doRun(repeat: Int): Unit = runBlockingSimulation {
         val meterProvider: MeterProvider = SdkMeterProvider
             .builder()
             .setClock(clock.toOtelClock())
             .build()
 
-        val trace = ServerlessTraceReader().parse(tracePath)
+        val trace = ServerlessTraceReader().parse(File(config.getString("trace-path")))
         val traceById = trace.associateBy { it.id }
         val delayInjector = StochasticDelayInjector(coldStartModel, Random())
         val deployer = SimFunctionDeployer(clock, this, createMachineModel(), delayInjector) { FunctionTraceWorkload(traceById.getValue(it.name)) }
diff --git a/opendc-experiments/opendc-experiments-serverless20/src/main/resources/application.conf b/opendc-experiments/opendc-experiments-serverless20/src/main/resources/application.conf
new file mode 100644
index 00000000..a065c5d6
--- /dev/null
+++ b/opendc-experiments/opendc-experiments-serverless20/src/main/resources/application.conf
@@ -0,0 +1,8 @@
+# Default configuration for the serverless experiments
+opendc.experiments.serverless20 {
+    # Path to the directory containing the serverless trace
+    trace-path = input/traces/serverless
+
+    # Path to the output directory to write the results to
+    output-path = output
+}