introduce Metrics.addProperty and use it instead of addMetadata

Author: humanzz

powertools-metrics/src/main/java/software/amazon/lambda/powertools/metrics/Metrics.java

@@ -93,6 +93,14 @@ default void addDimension(String key, String value) {
      */
     void addMetadata(String key, Object value);
 
+    /**
+     * Add property
+     *
+     * @param key   the name of the property
+     * @param value the value of the property
+     */
+    void addProperty(String key, Object value);
+
     /**
      * Set default dimensions
      *

powertools-metrics/src/main/java/software/amazon/lambda/powertools/metrics/internal/EmfMetricsLogger.java

@@ -54,7 +54,7 @@ public class EmfMetricsLogger implements Metrics {
     private final AtomicBoolean raiseOnEmptyMetrics = new AtomicBoolean(false);
     private String namespace;
     private Map<String, String> defaultDimensions = new HashMap<>();
-    private final Map<String, Object> metadata = new HashMap<>();
+    private final Map<String, Object> properties = new HashMap<>();
     private final AtomicBoolean hasMetrics = new AtomicBoolean(false);
 
     public EmfMetricsLogger(EnvironmentProvider environmentProvider, MetricsContext metricsContext) {
@@ -92,7 +92,12 @@ public void addDimension(software.amazon.lambda.powertools.metrics.model.Dimensi
     @Override
     public void addMetadata(String key, Object value) {
         emfLogger.putMetadata(key, value);
-        metadata.put(key, value);
+    }
+
+    @Override
+    public void addProperty(String key, Object value) {
+        emfLogger.putProperty(key, value);
+        properties.put(key, value);
     }
 
     @Override
@@ -235,7 +240,7 @@ public void flushMetrics(Consumer<Metrics> metricsConsumer) {
         if (!defaultDimensions.isEmpty()) {
             metrics.setDefaultDimensions(software.amazon.lambda.powertools.metrics.model.DimensionSet.of(defaultDimensions));
         }
-        metadata.forEach(metrics::addMetadata);
+        properties.forEach(metrics::addProperty);
 
         metricsConsumer.accept(metrics);
 

powertools-metrics/src/main/java/software/amazon/lambda/powertools/metrics/internal/LambdaMetricsAspect.java

@@ -92,7 +92,7 @@ public Object around(ProceedingJoinPoint pjp,
 
             // Add trace ID metadata if available
             LambdaHandlerProcessor.getXrayTraceId()
-                    .ifPresent(traceId -> metricsInstance.addMetadata(TRACE_ID_PROPERTY, traceId));
+                    .ifPresent(traceId -> metricsInstance.addProperty(TRACE_ID_PROPERTY, traceId));
 
             captureColdStartMetricIfEnabled(extractContext(pjp), metrics);
 
@@ -115,7 +115,7 @@ private void captureColdStartMetricIfEnabled(Context extractedContext, FlushMetr
         Metrics metricsInstance = MetricsFactory.getMetricsInstance();
         // This can be null e.g. during unit tests when mocking the Lambda context
         if (extractedContext.getAwsRequestId() != null) {
-            metricsInstance.addMetadata(REQUEST_ID_PROPERTY, extractedContext.getAwsRequestId());
+            metricsInstance.addProperty(REQUEST_ID_PROPERTY, extractedContext.getAwsRequestId());
         }
 
         // Only capture cold start metrics if enabled on annotation

powertools-metrics/src/test/java/software/amazon/lambda/powertools/metrics/internal/EmfMetricsLoggerTest.java

@@ -453,6 +453,7 @@ void shouldFlushMetrics() throws Exception {
         metrics.setDefaultDimensions(DimensionSet.of("CustomDim", "CustomValue"));
         metrics.addDimension(DimensionSet.of("CustomDim2", "CustomValue2"));
         metrics.addMetadata("CustomMetadata", "MetadataValue");
+        metrics.addProperty("CustomProperty", "PropertyValue");
 
         // When
         metrics.flushMetrics(m -> {
@@ -473,8 +474,9 @@ void shouldFlushMetrics() throws Exception {
         assertThat(rootNode.get("CustomDim2")).isNull();
         assertThat(rootNode.get("_aws").get("CloudWatchMetrics").get(0).get("Namespace").asText())
                 .isEqualTo("MainNamespace");
-        assertThat(rootNode.get("_aws").has("CustomMetadata")).isTrue();
-        assertThat(rootNode.get("_aws").get("CustomMetadata").asText()).isEqualTo("MetadataValue");
+        assertThat(rootNode.get("_aws").has("CustomMetadata")).isFalse();
+        assertThat(rootNode.has("CustomProperty")).isTrue();
+        assertThat(rootNode.get("CustomProperty").asText()).isEqualTo("PropertyValue");
     }
 
     @Test

powertools-metrics/src/test/java/software/amazon/lambda/powertools/metrics/testutils/TestMetrics.java

@@ -37,6 +37,11 @@ public void addMetadata(String key, Object value) {
         // Test placeholder
     }
 
+    @Override
+    public void addProperty(String key, Object value) {
+        // Test placeholder
+    }
+
     @Override
     public void setDefaultDimensions(DimensionSet dimensionSet) {
         // Test placeholder