basic component lifetimes working

engine-cli/src/main/java/io/nosqlbench/engine/cli/NBCLI.java

@@ -74,7 +74,7 @@ import java.util.ServiceLoader.Provider;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
-public class NBCLI extends NBBaseComponent implements Function<String[], Integer> {
+public class NBCLI implements Function<String[], Integer>, NBLabeledElement {
 
     private static Logger logger;
     private static final LoggerConfig loggerConfig;
@@ -88,17 +88,14 @@ public class NBCLI extends NBBaseComponent implements Function<String[], Integer
     }
 
     private final String commandName;
-
-    private NBLabels labels;
     private String sessionName;
     private String sessionCode;
     private long sessionTime;
-    private NBLabels extraLabels = NBLabels.forKV();
+    private NBLabels labels = NBLabels.forKV("appname","nosqlbench");
 
     private ClientSystemMetricChecker clientMetricChecker;
 
     public NBCLI(final String commandName) {
-        super(null, NBLabels.forKV("appname","nosqlbench"));
         this.commandName = commandName;
     }
 
@@ -166,14 +163,9 @@ public class NBCLI extends NBBaseComponent implements Function<String[], Integer
         NBCLI.loggerConfig.setConsoleLevel(NBLogLevel.ERROR);
         this.sessionTime = System.currentTimeMillis();
         final NBCLIOptions globalOptions = new NBCLIOptions(args, Mode.ParseGlobalsOnly);
-        this.extraLabels=globalOptions.getLabelMap();
+        this.labels=globalOptions.getLabelMap();
-
         this.sessionCode = SystemId.genSessionCode(sessionTime);
         this.sessionName = SessionNamer.format(globalOptions.getSessionName(), sessionTime).replaceAll("SESSIONCODE", sessionCode);
-        this.labels = NBLabels.forKV()
-            .and("appname", "nosqlbench")
-            .and("node", SystemId.getNodeId())
-            .and(globalOptions.getLabelMap());
 
         NBCLI.loggerConfig
             .setSessionName(sessionName)
@@ -439,7 +431,7 @@ public class NBCLI extends NBBaseComponent implements Function<String[], Integer
          * marshal and transform it for any scenario invocations directly.
          */
         NBSession session = new NBSession(
-            this,
+            new NBBaseComponent(null),
             sessionName,
             options.getProgressSpec(),
             options.getReportSummaryTo(),
@@ -595,7 +587,7 @@ public class NBCLI extends NBBaseComponent implements Function<String[], Integer
 
     @Override
     public NBLabels getLabels() {
-        return (extraLabels==null) ? super.getLabels() : super.getLabels().and(extraLabels);
+        return labels;
     }
 
 }

engine-cli/src/main/java/io/nosqlbench/engine/cli/NBCLIOptions.java

@@ -21,6 +21,7 @@ import io.nosqlbench.api.errors.BasicError;
 import io.nosqlbench.api.labels.NBLabelSpec;
 import io.nosqlbench.api.labels.NBLabels;
 import io.nosqlbench.api.logging.NBLogLevel;
+import io.nosqlbench.api.metadata.SystemId;
 import io.nosqlbench.api.system.NBStatePath;
 import io.nosqlbench.engine.api.metrics.IndicatorMode;
 import io.nosqlbench.engine.cli.Cmd.CmdType;
@@ -133,7 +134,8 @@ public class NBCLIOptions {
     //    private static final String DEFAULT_CONSOLE_LOGGING_PATTERN = "%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n";
 
 
-    private NBLabels labels = NBLabels.forKV();
+    private NBLabels labels = NBLabels.forKV("appname", "nosqlbench")
+        .and("node",SystemId.getNodeId());
     private final List<Cmd> cmdList = new ArrayList<>();
     private int logsMax;
     private boolean wantsVersionShort;

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/ExecutionResult.java

@@ -20,6 +20,8 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
 import java.io.PrintStream;
+import java.util.ArrayList;
+import java.util.List;
 
 /**
  * Provide a result type back to a caller, including the start and end times,
@@ -53,8 +55,15 @@ public class ExecutionResult {
     public ExecutionResult(long startedAt, long endedAt, String iolog, Exception error) {
         this.startedAt = startedAt;
         this.endedAt = endedAt;
+        List<String> elements = new ArrayList<>();
+        if (iolog!=null && iolog.isEmpty()) {
+            elements.add(iolog);
+        }
+        if (error!=null) {
+            elements.add("ERROR:" + error);
+        }
         this.exception = error;
-        this.iolog = ((iolog != null) ? iolog + "\n\n" : "") + exception;
+        this.iolog = String.join("\n",elements);
         this.status = (error==null) ? Status.OK : Status.ERROR;
         logger.debug("populating "+status+" scenario result");
 
@@ -73,7 +82,7 @@ public class ExecutionResult {
     }
 
     public String getIOLog() {
-        return this.iolog;
+        return this.iolog==null? "" : iolog;
     }
 
     public long getElapsedMillis() {
@@ -88,5 +97,14 @@ public class ExecutionResult {
         return this.status;
     }
 
-
+    @Override
+    public String toString() {
+        return "ExecutionResult{" +
+            "status=" + status +
+            ", startedAt=" + startedAt +
+            ", endedAt=" + endedAt +
+            ", exception=" + exception +
+            ", iolog='" + iolog + '\'' +
+            '}';
+    }
 }

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/activity/ActivityExecutor.java

@@ -21,6 +21,7 @@ import io.nosqlbench.api.engine.metrics.instruments.NBFunctionGauge;
 import io.nosqlbench.api.engine.metrics.instruments.NBMetricGauge;
 import io.nosqlbench.api.labels.NBLabeledElement;
 import io.nosqlbench.api.labels.NBLabels;
+import io.nosqlbench.components.NBComponentSubScope;
 import io.nosqlbench.engine.api.activityapi.core.*;
 import io.nosqlbench.engine.api.activityimpl.MotorState;
 import io.nosqlbench.api.annotations.Annotation;
@@ -397,7 +398,9 @@ public class ActivityExecutor implements NBLabeledElement, ActivityController, P
 
     @Override
     public ExecutionResult call() throws Exception {
-        shutdownHook=new ActivityExecutorShutdownHook(this);
+        try (NBComponentSubScope scope = new NBComponentSubScope(activity)) {
+
+            shutdownHook = new ActivityExecutorShutdownHook(this);
             Runtime.getRuntime().addShutdownHook(shutdownHook);
             long startAt = System.currentTimeMillis();
 
@@ -422,7 +425,7 @@ public class ActivityExecutor implements NBLabeledElement, ActivityController, P
             } catch (Exception e) {
                 this.exception = e;
             } finally {
-            stoppedAt=System.currentTimeMillis();
+                stoppedAt = System.currentTimeMillis();
                 unregisterMetrics();
                 activity.shutdownActivity();
                 activity.closeAutoCloseables();
@@ -432,6 +435,8 @@ public class ActivityExecutor implements NBLabeledElement, ActivityController, P
             }
         }
 
+    }
+
     /**
      * This waits for at least one motor to be in running, finished or stopped state.
      * A motor with enough cycles to read will go into a running state. A motor which has
@@ -463,6 +468,7 @@ public class ActivityExecutor implements NBLabeledElement, ActivityController, P
         NBMetricGauge gauge = new NBFunctionGauge(activity, () -> (double) this.motors.size(), "threads");
         this.threadsGauge = ActivityMetrics.gauge(gauge);
     }
+
     private void unregisterMetrics() {
         if (this.threadsGauge != null) {
         ActivityMetrics.unregister(this.threadsGauge);
@@ -571,8 +577,8 @@ public class ActivityExecutor implements NBLabeledElement, ActivityController, P
         } else {
             logger.warn("Activity was interrupted by process exit, shutting down ungracefully. Annotations are still submitted.");
         }
-        if (shutdownHook==null) return; // In case of a race condition, only prevented by object monitor
+        if (shutdownHook == null) return; // In case of a race condition, only prevented by object monitor
-        else shutdownHook=null;
+        else shutdownHook = null;
 
         stoppedAt = System.currentTimeMillis(); //TODO: Make only one endedAtMillis assignment
 

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/activity/ActivityLoader.java

@@ -20,7 +20,7 @@ import io.nosqlbench.components.NBComponent;
 import io.nosqlbench.api.engine.activityimpl.ActivityDef;
 import io.nosqlbench.engine.api.activityapi.core.Activity;
 import io.nosqlbench.engine.api.activityimpl.uniform.StandardActivityType;
-import io.nosqlbench.engine.core.lifecycle.scenario.Scenario;
+import io.nosqlbench.engine.core.lifecycle.scenario.NBScenario;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -35,9 +35,9 @@ import java.util.concurrent.ConcurrentHashMap;
 public class ActivityLoader {
     private static final Logger logger = LogManager.getLogger("ACTIVITIES");
     private final Map<String, Activity> activityMap = new ConcurrentHashMap<>();
-    private final Scenario scenario;
+    private final NBScenario scenario;
 
-    public ActivityLoader(final Scenario scenario) {
+    public ActivityLoader(final NBScenario scenario) {
         this.scenario = scenario;
     }
 

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/scenario/NBScenario.java

@@ -60,7 +60,7 @@ import java.nio.file.StandardOpenOption;
 import java.util.*;
 import java.util.concurrent.Callable;
 
-public class Scenario extends NBBaseComponent implements Callable<ExecutionMetricsResult> {
+public class NBScenario extends NBBaseComponent implements Callable<ExecutionMetricsResult> {
 
     private final String reportSummaryTo;
     private final Path logsPath;
@@ -85,11 +85,6 @@ public class Scenario extends NBBaseComponent implements Callable<ExecutionMetri
         EXECUTE_SCRIPT
     }
 
-    @Override
-    public NBLabels getLabels() {
-        return this.parentComponent.getLabels().and("scenario", this.scenarioName);
-    }
-
     public enum State {
         Scheduled,
         Running,
@@ -114,7 +109,7 @@ public class Scenario extends NBBaseComponent implements Callable<ExecutionMetri
         Graalvm
     }
 
-    public Scenario(
+    public NBScenario(
         final String scenarioName,
         final String progressInterval,
         final String reportSummaryTo,
@@ -133,9 +128,9 @@ public class Scenario extends NBBaseComponent implements Callable<ExecutionMetri
         this.invocation = invocation;
     }
 
-    public static Scenario forTesting(final String name, final String reportSummaryTo, NBComponent parent) {
+    public static NBScenario forTesting(final String name, final String reportSummaryTo, NBComponent parent) {
 
-        return new Scenario(
+        return new NBScenario(
             name,
             "console:10s",
             reportSummaryTo,
@@ -146,7 +141,7 @@ public class Scenario extends NBBaseComponent implements Callable<ExecutionMetri
         );
     }
 
-    public Scenario setLogger(final Logger logger) {
+    public NBScenario setLogger(final Logger logger) {
         this.logger = logger;
         return this;
     }
@@ -155,13 +150,13 @@ public class Scenario extends NBBaseComponent implements Callable<ExecutionMetri
         return this.logger;
     }
 
-    public Scenario addScriptText(final String scriptText) {
+    public NBScenario addScriptText(final String scriptText) {
         this.scripts.add(scriptText);
         return this;
     }
 
 
-    public Scenario addScriptFiles(final String... args) {
+    public NBScenario addScriptFiles(final String... args) {
         for (final String scriptFile : args) {
             final Path scriptPath = Paths.get(scriptFile);
             byte[] bytes = new byte[0];
@@ -462,7 +457,7 @@ public class Scenario extends NBBaseComponent implements Callable<ExecutionMetri
         if ((null == o) || (this.getClass() != o.getClass())) {
             return false;
         }
-        final Scenario scenario = (Scenario) o;
+        final NBScenario scenario = (NBScenario) o;
         return Objects.equals(this.scenarioName, scenario.scenarioName);
     }
 

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/scenario/ScenarioController.java

@@ -48,11 +48,11 @@ public class ScenarioController implements NBLabeledElement {
     private final ActivityLoader activityLoader;
 
     private final Map<String, ActivityRuntimeInfo> activityInfoMap = new ConcurrentHashMap<>();
-    private final Scenario scenario;
+    private final NBScenario scenario;
 
     private final ExecutorService activitiesExecutor;
 
-    public ScenarioController(Scenario scenario) {
+    public ScenarioController(NBScenario scenario) {
         this.scenario = scenario;
         this.activityLoader = new ActivityLoader(scenario);
 

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/scenario/ScenarioShutdownHook.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022 nosqlbench
+ * Copyright (c) 2022-2023 nosqlbench
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,10 +20,10 @@ import org.apache.logging.log4j.Logger;
 
 public class ScenarioShutdownHook extends Thread {
 
-    private final Scenario scenario;
+    private final NBScenario scenario;
     private final Logger logger;
 
-    public ScenarioShutdownHook(Scenario scenario) {
+    public ScenarioShutdownHook(NBScenario scenario) {
         this.scenario = scenario;
         logger = scenario.getLogger();
     }

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/scenario/ScenariosExecutor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022 nosqlbench
+ * Copyright (c) 2022-2023 nosqlbench
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -48,7 +48,7 @@ public class ScenariosExecutor {
         this.name = name;
     }
 
-    public synchronized void execute(Scenario scenario) {
+    public synchronized void execute(NBScenario scenario) {
         if (submitted.get(scenario.getScenarioName()) != null) {
             throw new BasicError("Scenario " + scenario.getScenarioName() + " is already defined. Remove it first to reuse the name.");
         }
@@ -110,7 +110,7 @@ public class ScenariosExecutor {
             throw new RuntimeException("executor still runningScenarios after awaiting all results for " + timeout
                 + "ms.  isTerminated:" + executor.isTerminated() + " isShutdown:" + executor.isShutdown());
         }
-        Map<Scenario, ExecutionMetricsResult> scenarioResultMap = new LinkedHashMap<>();
+        Map<NBScenario, ExecutionMetricsResult> scenarioResultMap = new LinkedHashMap<>();
         getAsyncResultStatus()
             .entrySet()
             .forEach(
@@ -142,9 +142,9 @@ public class ScenariosExecutor {
      *
      * @return map of async results, with incomplete results as Optional.empty()
      */
-    public Map<Scenario, Optional<ExecutionMetricsResult>> getAsyncResultStatus() {
+    public Map<NBScenario, Optional<ExecutionMetricsResult>> getAsyncResultStatus() {
 
-        Map<Scenario, Optional<ExecutionMetricsResult>> optResults = new LinkedHashMap<>();
+        Map<NBScenario, Optional<ExecutionMetricsResult>> optResults = new LinkedHashMap<>();
 
         for (SubmittedScenario submittedScenario : submitted.values()) {
             Future<ExecutionMetricsResult> resultFuture = submittedScenario.getResultFuture();
@@ -167,7 +167,7 @@ public class ScenariosExecutor {
         return optResults;
     }
 
-    public Optional<Scenario> getPendingScenario(String scenarioName) {
+    public Optional<NBScenario> getPendingScenario(String scenarioName) {
         return Optional.ofNullable(submitted.get(scenarioName)).map(SubmittedScenario::getScenario);
     }
 
@@ -193,7 +193,7 @@ public class ScenariosExecutor {
 
     public synchronized void stopScenario(String scenarioName, boolean rethrow) {
         logger.debug("#stopScenario(name=" + scenarioName + ", rethrow="+ rethrow+")");
-        Optional<Scenario> pendingScenario = getPendingScenario(scenarioName);
+        Optional<NBScenario> pendingScenario = getPendingScenario(scenarioName);
         if (pendingScenario.isPresent()) {
             pendingScenario.get().getScenarioController().forceStopScenario(10000, true);
         } else {
@@ -204,7 +204,7 @@ public class ScenariosExecutor {
     public synchronized void deleteScenario(String scenarioName) {
         stopScenario(scenarioName, false);
 
-        Optional<Scenario> pendingScenario = getPendingScenario(scenarioName);
+        Optional<NBScenario> pendingScenario = getPendingScenario(scenarioName);
         if (pendingScenario.isPresent()) {
             submitted.remove(scenarioName);
             logger.info(() -> "cancelled scenario " + scenarioName);
@@ -224,15 +224,15 @@ public class ScenariosExecutor {
     }
 
     private static class SubmittedScenario {
-        private final Scenario scenario;
+        private final NBScenario scenario;
         private final Future<ExecutionMetricsResult> resultFuture;
 
-        SubmittedScenario(Scenario scenario, Future<ExecutionMetricsResult> resultFuture) {
+        SubmittedScenario(NBScenario scenario, Future<ExecutionMetricsResult> resultFuture) {
             this.scenario = scenario;
             this.resultFuture = resultFuture;
         }
 
-        public Scenario getScenario() {
+        public NBScenario getScenario() {
             return scenario;
         }
 

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/scenario/ScenariosResults.java

@@ -30,14 +30,14 @@ public class ScenariosResults {
 
     private static final Logger logger = LogManager.getLogger(ScenariosResults.class);
     private final String scenariosExecutorName;
-    private final Map<Scenario, ExecutionMetricsResult> scenarioResultMap = new LinkedHashMap<>();
+    private final Map<NBScenario, ExecutionMetricsResult> scenarioResultMap = new LinkedHashMap<>();
 
 
     public ScenariosResults(ScenariosExecutor scenariosExecutor) {
         this.scenariosExecutorName = scenariosExecutor.getName();
     }
 
-    public ScenariosResults(ScenariosExecutor scenariosExecutor, Map<Scenario, ExecutionMetricsResult> map) {
+    public ScenariosResults(ScenariosExecutor scenariosExecutor, Map<NBScenario, ExecutionMetricsResult> map) {
         this.scenariosExecutorName = scenariosExecutor.getName();
         scenarioResultMap.putAll(map);
     }
@@ -58,8 +58,8 @@ public class ScenariosResults {
     }
 
     public void reportToLog() {
-        for (Map.Entry<Scenario, ExecutionMetricsResult> entry : this.scenarioResultMap.entrySet()) {
+        for (Map.Entry<NBScenario, ExecutionMetricsResult> entry : this.scenarioResultMap.entrySet()) {
-            Scenario scenario = entry.getKey();
+            NBScenario scenario = entry.getKey();
             ExecutionMetricsResult oresult = entry.getValue();
 
             logger.info(() -> "results for scenario: " + scenario);

engine-core/src/main/java/io/nosqlbench/engine/core/lifecycle/session/NBSession.java

@@ -20,13 +20,14 @@ import io.nosqlbench.components.NBComponent;
 import io.nosqlbench.components.NBBaseComponent;
 import io.nosqlbench.api.engine.metrics.ActivityMetrics;
 import io.nosqlbench.api.labels.NBLabels;
+import io.nosqlbench.components.NBComponentSubScope;
 import io.nosqlbench.engine.cli.BasicScriptBuffer;
 import io.nosqlbench.engine.cli.Cmd;
 import io.nosqlbench.engine.cli.ScriptBuffer;
 import io.nosqlbench.engine.core.lifecycle.ExecutionResult;
 import io.nosqlbench.engine.core.lifecycle.process.NBCLIErrorHandler;
 import io.nosqlbench.engine.core.lifecycle.process.ShutdownManager;
-import io.nosqlbench.engine.core.lifecycle.scenario.Scenario;
+import io.nosqlbench.engine.core.lifecycle.scenario.NBScenario;
 import io.nosqlbench.engine.core.lifecycle.scenario.ScenariosExecutor;
 import io.nosqlbench.engine.core.lifecycle.scenario.ScenariosResults;
 import io.nosqlbench.engine.core.lifecycle.scenario.script.ScriptParams;
@@ -82,9 +83,9 @@ public class NBSession extends NBBaseComponent implements Function<List<Cmd>, Ex
 
         try (ResultContext results = new ResultContext(collector)) {
             final ScenariosExecutor scenariosExecutor = new ScenariosExecutor("executor-" + sessionName, 1);
-            Scenario.Invocation invocation = wantsShowScript ? Scenario.Invocation.RENDER_SCRIPT : Scenario.Invocation.EXECUTE_SCRIPT;
+            NBScenario.Invocation invocation = wantsShowScript ? NBScenario.Invocation.RENDER_SCRIPT : NBScenario.Invocation.EXECUTE_SCRIPT;
 
-            final Scenario scenario = new Scenario(
+            final NBScenario scenario = new NBScenario(
                 sessionName,
                 progressSpec,
                 reportSummaryTo,
@@ -93,6 +94,7 @@ public class NBSession extends NBBaseComponent implements Function<List<Cmd>, Ex
                 this,
                 invocation
             );
+            try (NBComponentSubScope s = new NBComponentSubScope(scenario)) {
 
                 final ScriptBuffer buffer = new BasicScriptBuffer().add(cmds.toArray(new Cmd[0]));
                 final String scriptData = buffer.getParsedScript();
@@ -126,6 +128,9 @@ public class NBSession extends NBBaseComponent implements Function<List<Cmd>, Ex
                 }
 
                 results.output(scenariosResults.getExecutionSummary());
+
+            }
+
         }
         return collector.toExecutionResult();
     }

engine-core/src/test/java/io/nosqlbench/engine/core/NBScenarioTest.java

@@ -18,20 +18,20 @@ package io.nosqlbench.engine.core;
 
 import io.nosqlbench.api.config.standard.TestComponent;
 import io.nosqlbench.engine.api.scripting.ScriptEnvBuffer;
-import io.nosqlbench.engine.core.lifecycle.scenario.Scenario;
+import io.nosqlbench.engine.core.lifecycle.scenario.NBScenario;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class ScenarioTest {
+public class NBScenarioTest {
-    private final Logger logger = LogManager.getLogger(ScenarioTest.class);
+    private final Logger logger = LogManager.getLogger(NBScenarioTest.class);
 
     @Test
     public void shouldLoadScriptText() {
         ScriptEnvBuffer buffer = new ScriptEnvBuffer();
-        Scenario scenario = Scenario.forTesting("testing", "stdout:300", new TestComponent());
+        NBScenario scenario = NBScenario.forTesting("testing", "stdout:300", new TestComponent());
         scenario.addScriptText("print('loaded script environment...');\n");
         try {
             var result=scenario.call();

engine-core/src/test/java/io/nosqlbench/engine/core/script/NBScenarioContextBufferTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022 nosqlbench
+ * Copyright (c) 2022-2023 nosqlbench
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,7 +23,7 @@ import java.io.IOException;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class ScenarioContextBufferTest {
+public class NBScenarioContextBufferTest {
 
     @Test
     public void shouldCaptureLoggedOutput() throws IOException {

engine-core/src/test/java/io/nosqlbench/engine/core/script/ScenariosExecutorTest.java

@@ -17,7 +17,7 @@
 package io.nosqlbench.engine.core.script;
 
 import io.nosqlbench.api.config.standard.TestComponent;
-import io.nosqlbench.engine.core.lifecycle.scenario.Scenario;
+import io.nosqlbench.engine.core.lifecycle.scenario.NBScenario;
 import io.nosqlbench.engine.core.lifecycle.scenario.ScenariosExecutor;
 import io.nosqlbench.engine.core.lifecycle.scenario.ScenariosResults;
 import org.junit.jupiter.api.Disabled;
@@ -29,7 +29,7 @@ public class ScenariosExecutorTest {
     @Disabled
     public void testAwaitOnTime() {
         ScenariosExecutor e = new ScenariosExecutor(ScenariosExecutorTest.class.getSimpleName(), 1);
-        Scenario s = Scenario.forTesting("testing", "stdout:3000", new TestComponent());
+        NBScenario s = NBScenario.forTesting("testing", "stdout:3000", new TestComponent());
         s.addScriptText("load('classpath:scripts/asyncs.js');\nsetTimeout(\"print('waited')\",5000);\n");
         e.execute(s);
         ScenariosResults scenariosResults = e.awaitAllResults();

nb-api/src/main/java/io/nosqlbench/api/config/standard/TestComponent.java

@@ -19,37 +19,49 @@ package io.nosqlbench.api.config.standard;
 import io.nosqlbench.api.labels.NBLabels;
 import io.nosqlbench.components.NBBaseComponent;
 import io.nosqlbench.components.NBComponent;
-
+import org.apache.logging.log4j.LogManager;
-import java.util.Arrays;
+import org.apache.logging.log4j.Logger;
 
 public class TestComponent extends NBBaseComponent {
+    private final static Logger logger = LogManager.getLogger("RUNTIME");
 
     public static final NBComponent INSTANCE = new TestComponent();
 
     public TestComponent(String... labels) {
         super(null,NBLabels.forKV((Object[]) labels));
+//        logger.trace("new component " + description());
     }
 
     public TestComponent(NBComponent parent, String... labels) {
         super(parent, NBLabels.forKV((Object[]) labels));
+//        logger.trace("new component " + description());
     }
 
     @Override
     public String toString() {
-        return getLabels().linearizeAsMetrics() + " ("+this.getClass().getSimpleName()+")";
+        return description();
     }
 
     @Override
-    public NBComponent attach(NBComponent... children) {
+    public NBComponent attachChild(NBComponent... children) {
-        System.out.println("attaching children:" +
+        for (NBComponent child : children) {
-                Arrays.stream(children).map(c -> c.getLabels().linearizeAsMetrics()).toList());
+//            logger.debug("attaching " + child.description());
-        return super.attach(children);
+            super.attachChild(child);
+        }
+        return this;
     }
 
     @Override
-    public NBComponent detach(NBComponent... children) {
+    public NBComponent detachChild(NBComponent... children) {
-        System.out.println("detaching children:" +
+        for (NBComponent child : children) {
-                Arrays.stream(children).map(c -> c.getLabels().linearizeAsMetrics()).toList());
+//            logger.debug("detaching " + child.description());
-        return super.detach(children);
+            super.detachChild(child);
+        }
+        return this;
+    }
+
+    @Override
+    public void beforeDetach() {
+//        logger.debug("before detach " + description());
     }
 }

nb-api/src/main/java/io/nosqlbench/api/labels/MapLabels.java

@@ -122,6 +122,9 @@ public class MapLabels implements NBLabels {
 
     @Override
     public String linearizeAsMetrics() {
+        if (labels.isEmpty()) {
+            return "{}";
+        }
         StringBuilder sb = new StringBuilder("{");
         ArrayList<String> keys = new ArrayList<>(this.labels.keySet());
         Collections.sort(keys);

nb-api/src/main/java/io/nosqlbench/api/labels/NBLabeledElement.java

@@ -31,11 +31,10 @@ public interface NBLabeledElement {
     }
 
     NBLabels getLabels();
-
     class BasicLabeledElement implements NBLabeledElement {
         private final NBLabels labels;
         public BasicLabeledElement(final String... kvs) {
-            labels=NBLabels.forKV(kvs);
+            labels=NBLabels.forKV((Object[]) kvs);
         }
 
         public BasicLabeledElement(final Map<String, String> labels) {
@@ -48,4 +47,9 @@ public interface NBLabeledElement {
         }
     }
 
+    default String description() {
+        return this.getClass().getSimpleName() + " " + this.getLabels().linearizeAsMetrics();
+    }
+
+
 }

nb-api/src/main/java/io/nosqlbench/components/NBBaseComponent.java

@@ -18,13 +18,15 @@ package io.nosqlbench.components;
 
 import io.nosqlbench.api.engine.metrics.instruments.NBMetric;
 import io.nosqlbench.api.labels.NBLabels;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 
 import java.util.ArrayList;
-import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
 
 public class NBBaseComponent extends NBBaseComponentMetrics implements NBComponent {
+    private final static Logger logger = LogManager.getLogger("RUNTIME");
     private final NBComponent parent;
     private final List<NBComponent> children = new ArrayList<>();
     private final NBLabels labels;
@@ -36,7 +38,7 @@ public class NBBaseComponent extends NBBaseComponentMetrics implements NBCompone
         this.labels = componentSpecificLabelsOnly;
         if (parentComponent!=null) {
             parent = parentComponent;
-            parent.attach(this);
+            parent.attachChild(this);
         } else {
             parent=null;
         }
@@ -47,14 +49,21 @@ public class NBBaseComponent extends NBBaseComponentMetrics implements NBCompone
     }
 
     @Override
-    public NBComponent attach(NBComponent... children) {
+    public NBComponent attachChild(NBComponent... children) {
-        this.children.addAll(Arrays.asList(children));
+        for (NBComponent child : children) {
+            logger.debug(() -> "attaching " + child.description() + " to parent " + this.description());
+            this.children.add(child);
+        }
         return this;
     }
 
     @Override
-    public NBComponent detach(NBComponent... children) {
+    public NBComponent detachChild(NBComponent... children) {
-        this.children.removeAll(Arrays.asList(children));
+        for (NBComponent child : children) {
+            logger.debug(() -> "detaching " + child.description() + " from " + this.description());
+            this.children.remove(child);
+        }
+
         return this;
     }
 
@@ -89,4 +98,9 @@ public class NBBaseComponent extends NBBaseComponentMetrics implements NBCompone
         }
         return found;
     }
+
+    @Override
+    public void beforeDetach() {
+        logger.debug("before detach " + description());
+    }
 }

nb-api/src/main/java/io/nosqlbench/components/NBComponent.java

@@ -39,10 +39,11 @@ public interface NBComponent extends NBLabeledElement, NBComponentMetrics, NBMet
 
     NBComponent getParent();
 
-    NBComponent attach(NBComponent... children);
+    NBComponent attachChild(NBComponent... children);
 
-    NBComponent detach(NBComponent... children);
+    NBComponent detachChild(NBComponent... children);
 
     List<NBComponent> getChildren();
 
+    default void beforeDetach() {}
 }

nb-api/src/main/java/io/nosqlbench/components/NBComponentSubScope.java

@@ -25,6 +25,7 @@ public class NBComponentSubScope implements AutoCloseable {
     }
     @Override
     public void close() throws RuntimeException {
-        component.getParent().detach(component);
+        component.beforeDetach();
+        component.getParent().detachChild(component);
     }
 }

nb-api/src/main/java/io/nosqlbench/components/package-info.java

@@ -57,7 +57,7 @@
  * <P>Components are structured hierarchically. All components exist within the scope of their parent, with the only
  * exception being the root component, which has no parent. Components always know their parent from construction time.
  * After a component is constructed, it is informed of children components being added and removed via
- * {@link io.nosqlbench.components.NBComponent#attach} and {@link io.nosqlbench.components.NBComponent#detach}
+ * {@link io.nosqlbench.components.NBComponent#attachChild} and {@link io.nosqlbench.components.NBComponent#detachChild}
  * methods.</P>
  *
  * <P>Component logic should interact with other components using the component interfaces and types. No contextual

nb-api/src/test/java/io/nosqlbench/components/NBComponentLifecycleTest.java

@@ -17,9 +17,12 @@
 package io.nosqlbench.components;
 
 import io.nosqlbench.api.config.standard.TestComponent;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
 import org.junit.jupiter.api.Test;
 
 class NBComponentLifecycleTest {
+    private final static Logger logger = LogManager.getLogger(NBComponentLifecycleTest.class);
 
     @Test
     public void testBasicLifecycleHooks() {
@@ -28,13 +31,13 @@ class NBComponentLifecycleTest {
         TestComponent node2 = new TestComponent(root, "node2", "node2");
 
         try (NBComponentSubScope scope = new NBComponentSubScope(node1)) {
-            System.out.println("node1 active");
+            logger.info(node1.description() + " active");
        }
         try (NBComponentSubScope scope = new NBComponentSubScope(node2)) {
-            System.out.println("node2 active");
+            logger.info(node2.description() + " active");
         }
 
-        System.out.print("all inactive");
+        logger.info("all inactive");
 
     }
 

nb-api/src/test/java/io/nosqlbench/components/NBComponentViewsTest.java

@@ -30,10 +30,10 @@ class NBComponentViewsTest {
 
         var root2 = new TestComponent("a", "b");
 
-        root2.attach(new TestComponent(root2, "c", "d")
+        root2.attachChild(new TestComponent(root2, "c", "d")
-                .attach(new TestComponent("U", "V"))
+                .attachChild(new TestComponent("U", "V"))
-                .attach(new TestComponent("Y", "Z")))
+                .attachChild(new TestComponent("Y", "Z")))
-            .attach(new TestComponent("e", "f"));
+            .attachChild(new TestComponent("e", "f"));
 
         System.out.println("root1:\n" + NBComponentViews.treeView(root1));
         System.out.println("root1:\n" + NBComponentViews.treeView(root1, c -> String.valueOf(c.hashCode())));

nbr-examples/src/test/java/io/nosqlbench/nbr/examples/ScriptExampleTests.java

@@ -18,7 +18,7 @@ package io.nosqlbench.nbr.examples;
 
 import io.nosqlbench.api.config.standard.TestComponent;
 import io.nosqlbench.engine.core.lifecycle.ExecutionMetricsResult;
-import io.nosqlbench.engine.core.lifecycle.scenario.Scenario;
+import io.nosqlbench.engine.core.lifecycle.scenario.NBScenario;
 import io.nosqlbench.engine.core.lifecycle.scenario.ScenariosExecutor;
 import io.nosqlbench.engine.core.lifecycle.scenario.ScenariosResults;
 import org.apache.commons.compress.utils.IOUtils;
@@ -56,7 +56,7 @@ public class ScriptExampleTests {
         String scenarioName = "scenario " + scriptname;
         System.out.println("=".repeat(29) + " Running integration test for example scenario: " + scenarioName);
         ScenariosExecutor executor = new ScenariosExecutor(ScriptExampleTests.class.getSimpleName() + ":" + scriptname, 1);
-        Scenario s = Scenario.forTesting(scenarioName,"stdout:300", new TestComponent());
+        NBScenario s = NBScenario.forTesting(scenarioName,"stdout:300", new TestComponent());
 
         s.addScenarioScriptParams(paramsMap);