refactor: extract scheduling to new PowerMeasurer to simplify sensors

Also separate API from SPI classes.

deployment/src/main/java/io/quarkiverse/power/deployment/PowerProcessor.java

@@ -1,7 +1,7 @@
 package io.quarkiverse.power.deployment;
 
 import io.quarkiverse.power.deployment.devui.commands.PowerCommands;
-import io.quarkiverse.power.runtime.PowerSensorProducer;
+import io.quarkiverse.power.runtime.PowerMeasurer;
 import io.quarkus.deployment.IsDevelopment;
 import io.quarkus.deployment.annotations.BuildProducer;
 import io.quarkus.deployment.annotations.BuildStep;
@@ -20,7 +20,6 @@ FeatureBuildItem feature() {
     @BuildStep(onlyIf = IsDevelopment.class)
     void addConsoleCommands(BuildProducer<ConsoleCommandBuildItem> commands) {
         // register dev console commands
-        final var producer = new PowerSensorProducer();
-        commands.produce(new ConsoleCommandBuildItem(new PowerCommands(producer.sensor())));
+        commands.produce(new ConsoleCommandBuildItem(new PowerCommands(PowerMeasurer.instance())));
     }
 }

deployment/src/main/java/io/quarkiverse/power/deployment/devui/commands/PowerCommands.java

@@ -5,14 +5,15 @@
 import org.aesh.command.*;
 import org.aesh.command.invocation.CommandInvocation;
 
-import io.quarkiverse.power.runtime.PowerSensor;
+import io.quarkiverse.power.runtime.PowerMeasurer;
+import io.quarkiverse.power.runtime.SensorMeasure;
 
 @GroupCommandDefinition(name = "power", description = "Power consumption commands", generateHelp = true)
 @SuppressWarnings("rawtypes")
 public class PowerCommands implements GroupCommand {
-    private final PowerSensor<?> sensor;
+    private final PowerMeasurer<? extends SensorMeasure> sensor;
 
-    public PowerCommands(PowerSensor<?> sensor) {
+    public PowerCommands(PowerMeasurer<? extends SensorMeasure> sensor) {
         this.sensor = sensor;
     }
 

deployment/src/main/java/io/quarkiverse/power/deployment/devui/commands/StartCommand.java

@@ -6,21 +6,21 @@
 import org.aesh.command.invocation.CommandInvocation;
 import org.aesh.command.option.Option;
 
-import io.quarkiverse.power.runtime.PowerSensor;
+import io.quarkiverse.power.runtime.PowerMeasurer;
+import io.quarkiverse.power.runtime.SensorMeasure;
 import io.quarkus.deployment.console.QuarkusCommand;
 
 @CommandDefinition(name = "start", description = "Starts measuring power consumption of the current application")
-@SuppressWarnings("rawtypes")
 public class StartCommand extends QuarkusCommand {
-    private final PowerSensor<?> sensor;
+    private final PowerMeasurer<? extends SensorMeasure> sensor;
 
     @Option(name = "stopAfter", shortName = 's', description = "Automatically stop the measures after the specified duration in seconds", defaultValue = "-1")
     private long duration;
 
     @Option(name = "frequency", shortName = 'f', description = "The frequency at which measurements should be taken, in milliseconds", defaultValue = "1000")
     private long frequency;
 
-    public StartCommand(PowerSensor<?> sensor) {
+    public StartCommand(PowerMeasurer<? extends SensorMeasure> sensor) {
         this.sensor = sensor;
     }
 

deployment/src/main/java/io/quarkiverse/power/deployment/devui/commands/StopCommand.java

@@ -5,23 +5,22 @@
 import org.aesh.command.CommandResult;
 import org.aesh.command.invocation.CommandInvocation;
 
-import io.quarkiverse.power.runtime.PowerSensor;
+import io.quarkiverse.power.runtime.PowerMeasurer;
+import io.quarkiverse.power.runtime.SensorMeasure;
 import io.quarkus.deployment.console.QuarkusCommand;
 
 @CommandDefinition(name = "stop", description = "Stops power measurement and outputs accumulated power since measures were started")
-@SuppressWarnings("rawtypes")
 public class StopCommand extends QuarkusCommand {
 
-    private final PowerSensor sensor;
+    private final PowerMeasurer<? extends SensorMeasure> sensor;
 
-    public StopCommand(PowerSensor<?> sensor) {
+    public StopCommand(PowerMeasurer<? extends SensorMeasure> sensor) {
         this.sensor = sensor;
     }
 
     @Override
     public CommandResult doExecute(CommandInvocation commandInvocation) throws CommandException, InterruptedException {
-        sensor.stop();
-        sensor.outputConsumptionSinceStarted(commandInvocation::println);
+        sensor.stop(commandInvocation::println);
 
         return CommandResult.SUCCESS;
     }

runtime/src/main/java/io/quarkiverse/power/runtime/PowerMeasure.java

@@ -0,0 +1,9 @@
+package io.quarkiverse.power.runtime;
+
+public interface PowerMeasure<M extends SensorMeasure> extends SensorMeasure {
+    int numberOfSamples();
+
+    long duration();
+
+    M sensorMeasure();
+}

runtime/src/main/java/io/quarkiverse/power/runtime/PowerMeasurer.java

@@ -0,0 +1,77 @@
+package io.quarkiverse.power.runtime;
+
+import java.lang.management.ManagementFactory;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+
+import com.sun.management.OperatingSystemMXBean;
+
+import io.quarkiverse.power.runtime.sensors.IncrementableMeasure;
+import io.quarkiverse.power.runtime.sensors.OngoingPowerMeasure;
+import io.quarkiverse.power.runtime.sensors.PowerSensor;
+import io.quarkiverse.power.runtime.sensors.PowerSensorProducer;
+
+public class PowerMeasurer<M extends IncrementableMeasure> {
+    public static final OperatingSystemMXBean osBean;
+
+    static {
+        osBean = (OperatingSystemMXBean) ManagementFactory.getOperatingSystemMXBean();
+    }
+
+    private final ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();
+    private ScheduledFuture<?> scheduled;
+    private final PowerSensor<M> sensor;
+    private OngoingPowerMeasure<M> measure;
+
+    private final static PowerMeasurer<? extends SensorMeasure> instance = new PowerMeasurer<>(
+            PowerSensorProducer.determinePowerSensor());
+
+    public static PowerMeasurer<? extends SensorMeasure> instance() {
+        return instance;
+    }
+
+    public PowerMeasurer(PowerSensor<M> sensor) {
+        this.sensor = sensor;
+    }
+
+    public void start(long duration, long frequency, PowerSensor.Writer out) throws Exception {
+        if (measure == null) {
+            measure = sensor.start(duration, frequency, out);
+
+            if (duration > 0) {
+                executor.schedule(() -> stop(out), duration, TimeUnit.SECONDS);
+            }
+
+            scheduled = executor.scheduleAtFixedRate(() -> update(out),
+                    0, frequency,
+                    TimeUnit.MILLISECONDS);
+        }
+    }
+
+    private void update(PowerSensor.Writer out) {
+        sensor.update(measure, out);
+        measure.incrementSamples();
+    }
+
+    public PowerMeasure<M> stop(PowerSensor.Writer out) {
+        if (measure != null) {
+            sensor.stop();
+            scheduled.cancel(true);
+        }
+        outputConsumptionSinceStarted(out);
+        return measure;
+    }
+
+    public PowerMeasure<M> current() {
+        return measure;
+    }
+
+    private void outputConsumptionSinceStarted(PowerSensor.Writer out) {
+        out = out == null ? System.out::println : out;
+        out.println("Consumed " + measure.total() + " mW over " + (measure.duration() / 1000)
+                + " seconds (" + measure.numberOfSamples() + " samples)");
+        sensor.additionalInfo(out);
+    }
+}

runtime/src/main/java/io/quarkiverse/power/runtime/SensorMeasure.java

@@ -0,0 +1,28 @@
+package io.quarkiverse.power.runtime;
+
+import java.util.Optional;
+
+public interface SensorMeasure {
+    String CPU = "cpu";
+    String GPU = "gpu";
+    String TOTAL = "total";
+
+    double cpu();
+
+    default Optional<Double> gpu() {
+        return Optional.empty();
+    }
+
+    default Optional<Double> byKey(String key) {
+        return switch (key) {
+            case CPU -> Optional.of(cpu());
+            case GPU -> gpu();
+            case TOTAL -> Optional.of(total());
+            default -> Optional.empty();
+        };
+    }
+
+    default double total() {
+        return cpu() + gpu().orElse(0.0);
+    }
+}

runtime/src/main/java/io/quarkiverse/power/runtime/sensors/IncrementableMeasure.java

@@ -0,0 +1,11 @@
+package io.quarkiverse.power.runtime.sensors;
+
+import io.quarkiverse.power.runtime.SensorMeasure;
+
+public interface IncrementableMeasure extends SensorMeasure {
+
+    void addCPU(double v);
+
+    default void addGPU(double v) {
+    }
+}

runtime/src/main/java/io/quarkiverse/power/runtime/sensors/OngoingPowerMeasure.java

@@ -0,0 +1,64 @@
+package io.quarkiverse.power.runtime.sensors;
+
+import java.util.Optional;
+
+import io.quarkiverse.power.runtime.PowerMeasure;
+
+public class OngoingPowerMeasure<M extends IncrementableMeasure>
+        implements IncrementableMeasure, PowerMeasure<M> {
+    private final M measure;
+    private final long startedAt;
+    private int samplesNb;
+
+    public OngoingPowerMeasure(M measure) {
+        startedAt = System.currentTimeMillis();
+        samplesNb = 0;
+        this.measure = measure;
+    }
+
+    public void incrementSamples() {
+        samplesNb++;
+    }
+
+    @Override
+    public double cpu() {
+        return measure.cpu();
+    }
+
+    @Override
+    public Optional<Double> gpu() {
+        return measure.gpu();
+    }
+
+    @Override
+    public Optional<Double> byKey(String key) {
+        return measure.byKey(key);
+    }
+
+    @Override
+    public double total() {
+        return measure.total();
+    }
+
+    public int numberOfSamples() {
+        return samplesNb;
+    }
+
+    public long duration() {
+        return System.currentTimeMillis() - startedAt;
+    }
+
+    @Override
+    public void addCPU(double v) {
+        measure.addCPU(v);
+    }
+
+    @Override
+    public void addGPU(double v) {
+        measure.addGPU(v);
+    }
+
+    public M sensorMeasure() {
+        return measure;
+    }
+}

runtime/src/main/java/io/quarkiverse/power/runtime/sensors/PowerSensor.java

@@ -0,0 +1,18 @@
+package io.quarkiverse.power.runtime.sensors;
+
+public interface PowerSensor<T extends IncrementableMeasure> {
+
+    OngoingPowerMeasure<T> start(long duration, long frequency, Writer out) throws Exception;
+
+    default void stop() {
+    }
+
+    void update(OngoingPowerMeasure<T> ongoingMeasure, Writer out);
+
+    default void additionalInfo(Writer out) {
+    }
+
+    interface Writer {
+        void println(String message);
+    }
+}

runtime/src/main/java/io/quarkiverse/power/runtime/PowerSensorProducer.java → runtime/src/main/java/io/quarkiverse/power/runtime/sensors/PowerSensorProducer.java

@@ -1,4 +1,4 @@
-package io.quarkiverse.power.runtime;
+package io.quarkiverse.power.runtime.sensors;
 
 import jakarta.enterprise.inject.Produces;
 import jakarta.inject.Singleton;
@@ -10,6 +10,10 @@
 public class PowerSensorProducer {
     @Produces
     public PowerSensor<?> sensor() {
+        return determinePowerSensor();
+    }
+
+    public static PowerSensor<? extends IncrementableMeasure> determinePowerSensor() {
         final var originalOSName = System.getProperty("os.name");
         String osName = originalOSName.toLowerCase();