Make Titan record generator testable

theodolite-benchmarks/load-generator-commons/src/main/java/theodolite/commons/workloadgeneration/LoadGenerator.java

@@ -95,7 +95,7 @@ public final class LoadGenerator {
             new KeySpace(SENSOR_PREFIX_DEFAULT, NUMBER_OF_KEYS_DEFAULT),
             Duration.ofMillis(PERIOD_MS_DEFAULT)))
         .setGeneratorConfig(new LoadGeneratorConfig(
-            TitanRecordGeneratorFactory.forConstantValue(VALUE_DEFAULT),
+            TitanRecordGenerator.forConstantValue(VALUE_DEFAULT),
             TitanKafkaSenderFactory.forKafkaConfig(
                 KAFKA_BOOTSTRAP_SERVERS_DEFAULT,
                 KAFKA_TOPIC_DEFAULT,
@@ -198,7 +198,7 @@ public final class LoadGenerator {
             new KeySpace(SENSOR_PREFIX_DEFAULT, numSensors),
             Duration.ofMillis(periodMs)))
         .setGeneratorConfig(new LoadGeneratorConfig(
-            TitanRecordGeneratorFactory.forConstantValue(value),
+            TitanRecordGenerator.forConstantValue(value),
             recordSender))
         .withThreads(threads);
   }

theodolite-benchmarks/load-generator-commons/src/main/java/theodolite/commons/workloadgeneration/TitanRecordGeneratorFactory.java → theodolite-benchmarks/load-generator-commons/src/main/java/theodolite/commons/workloadgeneration/TitanRecordGenerator.java

 package theodolite.commons.workloadgeneration;
 
+import java.time.Clock;
 import titan.ccp.model.records.ActivePowerRecord;
 
 /**
  * A factory for creating {@link RecordGenerator}s that creates Titan {@link ActivePowerRecord}s.
  */
-public final class TitanRecordGeneratorFactory {
+public final class TitanRecordGenerator implements RecordGenerator<ActivePowerRecord> {
 
+  private final Clock clock;
 
-  private TitanRecordGeneratorFactory() {}
+  private final double constantValue;
+
+  private TitanRecordGenerator(final double constantValue) {
+    this.constantValue = constantValue;
+    this.clock = Clock.systemUTC();
+  }
+
+  /* default */ TitanRecordGenerator(final double constantValue, final Clock clock) {
+    this.constantValue = constantValue;
+    this.clock = clock;
+  }
 
   /**
    * Create a {@link RecordGenerator} that generates Titan {@link ActivePowerRecord}s with a
    * constant value.
    */
   public static RecordGenerator<ActivePowerRecord> forConstantValue(final double value) {
-    return sensor -> new ActivePowerRecord(sensor, System.currentTimeMillis(), value);
+    return new TitanRecordGenerator(value);
+  }
+
+  @Override
+  public ActivePowerRecord generate(final String key) {
+    return new ActivePowerRecord(key, this.clock.millis(), this.constantValue);
   }
 
 }

theodolite-benchmarks/load-generator-commons/src/test/java/theodolite/commons/workloadgeneration/TitanRecordGeneratorTest.java

+package theodolite.commons.workloadgeneration;
+
+import java.time.Clock;
+import java.time.Instant;
+import java.time.LocalDateTime;
+import java.time.ZoneId;
+import java.time.ZoneOffset;
+import org.junit.Assert;
+import org.junit.Test;
+import titan.ccp.model.records.ActivePowerRecord;
+
+public class TitanRecordGeneratorTest {
+
+  @Test
+  public void testGenerate() {
+    final ZoneId zoneId = ZoneOffset.UTC;
+    final LocalDateTime dateTime = LocalDateTime.of(2022, 1, 17, 14, 2, 42);
+    final Instant instant = dateTime.atZone(zoneId).toInstant();
+    final TitanRecordGenerator generator =
+        new TitanRecordGenerator(42.0, Clock.fixed(instant, zoneId));
+
+    final ActivePowerRecord activePowerRecord = generator.generate("my-identifier");
+    Assert.assertEquals("my-identifier", activePowerRecord.getIdentifier());
+    Assert.assertEquals(instant.toEpochMilli(), activePowerRecord.getTimestamp());
+    Assert.assertEquals(42.0, activePowerRecord.getValueInW(), 0.001);
+  }
+
+  @Test
+  public void testTimestampForArbitraryClockTimeZone() {
+    final LocalDateTime dateTime = LocalDateTime.of(2022, 1, 17, 14, 2, 42);
+    final Instant instant = dateTime.atZone(ZoneId.of("Europe/Paris")).toInstant();
+    // Setting of ZoneId should have no impact on result as we request epoch millis
+    final Clock clock = Clock.fixed(instant, ZoneId.of("America/Sao_Paulo"));
+    final TitanRecordGenerator generator = new TitanRecordGenerator(42.0, clock);
+
+    final ActivePowerRecord activePowerRecord = generator.generate("my-identifier");
+    Assert.assertEquals(instant.toEpochMilli(), activePowerRecord.getTimestamp());
+  }
+
+}