add isempty check for namespace

Author: liustve

awsagentprovider/src/main/java/software/amazon/opentelemetry/javaagent/providers/exporter/aws/metrics/AwsCloudWatchEmfExporterBuilder.java

@@ -61,9 +61,6 @@ public AwsCloudWatchEmfExporterBuilder setShouldAddApplicationSignalsDimensions(
   }
 
   public AwsCloudWatchEmfExporter build() {
-    if (this.namespace == null) {
-      this.namespace = "default";
-    }
 
     if (this.emitter == null) {
       requireNonNull(logGroupName, "Must set logGroupName when emitter is not provided");

awsagentprovider/src/main/java/software/amazon/opentelemetry/javaagent/providers/exporter/aws/metrics/ConsoleEmfExporterBuilder.java

@@ -41,9 +41,6 @@ public ConsoleEmfExporterBuilder setShouldAddApplicationSignalsDimensions(
   }
 
   public ConsoleEmfExporter build() {
-    if (this.namespace == null) {
-      this.namespace = "default";
-    }
     if (this.emitter == null) {
       this.emitter = new ConsoleEmitter();
     }

awsagentprovider/src/main/java/software/amazon/opentelemetry/javaagent/providers/exporter/aws/metrics/common/BaseEmfExporter.java

@@ -61,7 +61,10 @@ public abstract class BaseEmfExporter<T> implements MetricExporter {
    */
   protected BaseEmfExporter(
       String namespace, LogEventEmitter<T> emitter, boolean shouldAddApplicationSignalsDimensions) {
-    this.namespace = namespace != null ? namespace : "default";
+    if (emitter == null) {
+      throw new IllegalArgumentException("Given emitter must not be null");
+    }
+    this.namespace = namespace == null || namespace.isEmpty() ? "default" : namespace;
     this.emitter = emitter;
     this.shouldAddApplicationSignalsDimensions = shouldAddApplicationSignalsDimensions;
   }

awsagentprovider/src/test/java/software/amazon/opentelemetry/javaagent/providers/exporter/aws/metrics/AwsCloudWatchEmfExporterTest.java

@@ -64,17 +64,20 @@ protected LogEventEmitter<CloudWatchLogsClient> createEmitter() {
   }
 
   @Override
-  protected MetricExporter buildExporter(boolean shouldAddAppSignals) {
+  protected MetricExporter buildExporter(
+      LogEventEmitter<CloudWatchLogsClient> emitter,
+      String namespace,
+      boolean shouldAddAppSignals) {
     return AwsCloudWatchEmfExporter.builder()
-        .setNamespace(NAMESPACE)
-        .setEmitter(this.mockEmitter)
+        .setNamespace(namespace)
+        .setEmitter(emitter)
         .setShouldAddApplicationSignalsDimensions(shouldAddAppSignals)
         .build();
   }
 
   @Test
   void testShutdown() {
-    MetricExporter spyExporter = spy(buildExporter(false));
+    MetricExporter spyExporter = spy(buildExporter(this.mockEmitter, NAMESPACE, false));
     doNothing().when(this.mockEmitter).flushEvents();
 
     CompletableResultCode result = spyExporter.shutdown();
@@ -246,14 +249,15 @@ void testBatchInactiveAfter24Hours() {
   @MethodSource("batchLimitScenarios")
   void testEventBatchLimits(
       Map<String, Object> logEvent, int eventCount, boolean shouldExceedLimit) {
+    LogEventEmitter<CloudWatchLogsClient> testEmitter = createEmitter();
     for (int i = 0; i < eventCount; i++) {
-      this.mockEmitter.emit(logEvent);
+      testEmitter.emit(logEvent);
     }
 
     if (shouldExceedLimit) {
-      verify(this.mockEmitter, atLeast(2)).emit(logEvent);
+      verify(testEmitter, atLeast(2)).emit(logEvent);
     } else {
-      verify(this.mockEmitter, times(eventCount)).emit(logEvent);
+      verify(testEmitter, times(eventCount)).emit(logEvent);
     }
   }
 

awsagentprovider/src/test/java/software/amazon/opentelemetry/javaagent/providers/exporter/aws/metrics/BaseEmfExporterTest.java

@@ -63,13 +63,14 @@ public abstract class BaseEmfExporterTest<T> {
 
   abstract LogEventEmitter<T> createEmitter();
 
-  abstract MetricExporter buildExporter(boolean shouldAddAppSignals);
+  abstract MetricExporter buildExporter(
+      LogEventEmitter<T> emitter, String namespace, boolean shouldAddAppSignals);
 
   @BeforeEach
   void setup() {
     this.capturedLogEvents = new ArrayList<>();
     this.mockEmitter = this.createEmitter();
-    this.exporter = this.buildExporter(false);
+    this.exporter = this.buildExporter(mockEmitter, NAMESPACE, false);
     this.metricData = mock(MetricData.class);
 
     doAnswer(
@@ -90,6 +91,18 @@ void testExportEmptyMetrics() {
     assertEquals(0, capturedLogEvents.size());
   }
 
+  @Test
+  void testNullNamespaceDefaultsToDefault() {
+    MetricExporter exporter = buildExporter(createEmitter(), null, false);
+    assertNotNull(exporter);
+  }
+
+  @Test
+  void testEmptyNamespaceDefaultsToDefault() {
+    MetricExporter exporter = buildExporter(createEmitter(), "", false);
+    assertNotNull(exporter);
+  }
+
   @Test
   void testExportFailureHandling() {
     doThrow(new RuntimeException("Test exception")).when(mockEmitter).emit(any());
@@ -268,7 +281,7 @@ void testExponentialHistogramMetricProcessing() {
   @MethodSource("applicationSignalsDimensionsProvider")
   void testApplicationSignalsDimensions(
       Map<String, String> resourceAttrs, String expectedService, String expectedEnvironment) {
-    MetricExporter exporterWithAppSignals = buildExporter(true);
+    MetricExporter exporterWithAppSignals = buildExporter(mockEmitter, NAMESPACE, true);
 
     Resource resource = Resource.empty();
     for (Map.Entry<String, String> entry : resourceAttrs.entrySet()) {

awsagentprovider/src/test/java/software/amazon/opentelemetry/javaagent/providers/exporter/aws/metrics/ConsoleEmfExporterTest.java

@@ -55,10 +55,11 @@ protected LogEventEmitter<PrintStream> createEmitter() {
   }
 
   @Override
-  protected MetricExporter buildExporter(boolean shouldAddAppSignals) {
+  protected MetricExporter buildExporter(
+      LogEventEmitter<PrintStream> emitter, String namespace, boolean shouldAddAppSignals) {
     return ConsoleEmfExporter.builder()
-        .setNamespace(NAMESPACE)
-        .setEmitter(mockEmitter)
+        .setNamespace(namespace)
+        .setEmitter(emitter)
         .setShouldAddApplicationSignalsDimensions(shouldAddAppSignals)
         .build();
   }