fix(sourceprocessor): don't ignore empty annotation values

Annotation values which are empty strings should be treated like any
other value, and not ignored as if they didn't exist.

.changelog/1569.fixed.txt

@@ -0,0 +1 @@
+fix(sourceprocessor): don't ignore empty annotation values

pkg/processor/sourceprocessor/source_category_filler.go

@@ -104,35 +104,31 @@ func (f *sourceCategoryFiller) fill(attributes *pcommon.Map) {
 }
 
 func (f *sourceCategoryFiller) getSourceCategoryDashReplacement(attributes *pcommon.Map) string {
-	dashReplacement := getAnnotationAttributeValue(f.annotationPrefix, sourceCategoryReplaceDashAnnotation, attributes)
-	if dashReplacement != "" {
+	dashReplacement, found := getAnnotationAttributeValue(f.annotationPrefix, sourceCategoryReplaceDashAnnotation, attributes)
+	if found {
 		return dashReplacement
 	}
 
-	dashReplacement = getAnnotationAttributeValue(f.namespaceAnnotationPrefix, sourceCategoryReplaceDashAnnotation, attributes)
-	if dashReplacement != "" {
+	dashReplacement, found = getAnnotationAttributeValue(f.namespaceAnnotationPrefix, sourceCategoryReplaceDashAnnotation, attributes)
+	if found {
 		return dashReplacement
 	}
 	return f.dashReplacement
 }
 
 func (f *sourceCategoryFiller) getSourceCategoryFromAnnotation(annotationPrefix string, attributes *pcommon.Map) (string, bool) {
-	doesUseAnnotation := false
-
-	valueTemplate := getAnnotationAttributeValue(annotationPrefix, sourceCategorySpecialAnnotation, attributes)
-	if valueTemplate == "" {
+	valueTemplate, foundTemplate := getAnnotationAttributeValue(annotationPrefix, sourceCategorySpecialAnnotation, attributes)
+	if !foundTemplate {
 		valueTemplate = f.valueTemplate
-	} else {
-		doesUseAnnotation = true
 	}
 
-	prefix := getAnnotationAttributeValue(annotationPrefix, sourceCategoryPrefixAnnotation, attributes)
-	if prefix == "" {
+	prefix, foundPrefix := getAnnotationAttributeValue(annotationPrefix, sourceCategoryPrefixAnnotation, attributes)
+	if !foundPrefix {
 		prefix = f.prefix
-	} else {
-		doesUseAnnotation = true
 	}
+
 	valueTemplate = prefix + valueTemplate
+	doesUseAnnotation := foundPrefix || foundTemplate
 	return valueTemplate, doesUseAnnotation
 }
 
@@ -150,8 +146,8 @@ func (f *sourceCategoryFiller) getSourceCategoryFromContainerAnnotation(attribut
 
 	for _, containerAnnotationPrefix := range f.containerAnnotationsPrefixes {
 		annotationKey := fmt.Sprintf("%s%s.sourceCategory", containerAnnotationPrefix, containerName.Str())
-		annotationValue := getAnnotationAttributeValue(f.annotationPrefix, annotationKey, attributes)
-		if annotationValue != "" {
+		annotationValue, found := getAnnotationAttributeValue(f.annotationPrefix, annotationKey, attributes)
+		if found {
 			f.logger.Debug("Filled source category from container annotation",
 				zap.String("annotation", annotationKey),
 				zap.String("source_category", annotationValue),
@@ -181,10 +177,10 @@ func (f *sourceCategoryFiller) replaceTemplateAttributes(template string, templa
 	return strings.NewReplacer(replacerArgs...).Replace(template)
 }
 
-func getAnnotationAttributeValue(annotationAttributePrefix string, annotation string, attributes *pcommon.Map) string {
+func getAnnotationAttributeValue(annotationAttributePrefix string, annotation string, attributes *pcommon.Map) (string, bool) {
 	annotationAttribute, found := attributes.Get(annotationAttributePrefix + annotation)
 	if found {
-		return annotationAttribute.Str()
+		return annotationAttribute.Str(), found
 	}
-	return ""
+	return "", false
 }

pkg/processor/sourceprocessor/source_category_filler_test.go

@@ -66,6 +66,33 @@ func TestFillWithAnnotations(t *testing.T) {
 	assertAttribute(t, attrs, "_sourceCategory", "ABC#123asd#Prefix:sc#from#annot#ns#1#123asd")
 }
 
+func TestFillWithEmptyAnnotations(t *testing.T) {
+	cfg := createDefaultConfig().(*Config)
+	cfg.SourceCategoryPrefix = "prefix"
+
+	attrs := pcommon.NewMap()
+	attrs.PutStr("k8s.namespace.name", "ns-1")
+	attrs.PutStr("k8s.pod.uid", "123asd")
+	attrs.PutStr("k8s.pod.pod_name", "ABC")
+
+	filler := newSourceCategoryFiller(cfg, zap.NewNop())
+
+	// can replace prefix with an empty string
+	attrs.PutStr("k8s.pod.annotation.sumologic.com/sourceCategoryPrefix", "")
+	filler.fill(&attrs)
+	assertAttribute(t, attrs, "_sourceCategory", "ns/1/ABC")
+
+	// can replace dash with an empty string
+	attrs.PutStr("k8s.pod.annotation.sumologic.com/sourceCategoryReplaceDash", "")
+	filler.fill(&attrs)
+	assertAttribute(t, attrs, "_sourceCategory", "ns1/ABC")
+
+	// can replace source category with empty string
+	attrs.PutStr("k8s.pod.annotation.sumologic.com/sourceCategory", "")
+	filler.fill(&attrs)
+	assertAttribute(t, attrs, "_sourceCategory", "")
+}
+
 func TestFillWithNamespaceAnnotations(t *testing.T) {
 	cfg := createDefaultConfig().(*Config)
 

pkg/processor/sourceprocessor/source_processor_test.go

@@ -499,6 +499,18 @@ func TestSourceCategoryAnnotations(t *testing.T) {
 		assertAttribute(t, processedAttributes, "_sourceCategory", "annot>namespace#1/pod")
 	})
 
+	t.Run("source category empty prefix annotation", func(t *testing.T) {
+		inputAttributes := createK8sLabels()
+		inputAttributes["pod_annotation_sumologic.com/sourceCategoryPrefix"] = ""
+		inputTraces := newTraceData(inputAttributes)
+
+		processedTraces, err := newSourceProcessor(newProcessorCreateSettings(), cfg).ProcessTraces(context.Background(), inputTraces)
+		assert.NoError(t, err)
+
+		processedAttributes := processedTraces.ResourceSpans().At(0).Resource().Attributes()
+		assertAttribute(t, processedAttributes, "_sourceCategory", "namespace#1/pod")
+	})
+
 	t.Run("source category dash replacement annotation", func(t *testing.T) {
 		inputAttributes := createK8sLabels()
 		inputAttributes["pod_annotation_sumologic.com/sourceCategoryReplaceDash"] = "^"
@@ -649,14 +661,12 @@ func TestSourceCategoryTemplateWithCustomAttribute(t *testing.T) {
 func assertAttribute(t *testing.T, attributes pcommon.Map, attributeName string, expectedValue string) {
 	value, exists := attributes.Get(attributeName)
 
-	if expectedValue == "" {
+	if !exists {
 		assert.False(t, exists, "Attribute '%s' should not exist.", attributeName)
 	} else {
 		assert.True(t, exists, "Attribute '%s' should exist, but it does not.", attributeName)
-		if exists {
-			actualValue := value.Str()
-			assert.Equal(t, expectedValue, actualValue, "Attribute '%s' should be '%s', but was '%s'.", attributeName, expectedValue, actualValue)
-		}
+		actualValue := value.Str()
+		assert.Equal(t, expectedValue, actualValue, "Attribute '%s' should be '%s', but was '%s'.", attributeName, expectedValue, actualValue)
 	}
 }