correct behavior of glob-based attribute selection (#995)

pkg/internal/export/attributes/attr_selector.go

@@ -73,18 +73,17 @@ func (p *AttrSelector) For(metricName Name) Sections[[]attr.Name] {
 		Metric:   map[attr.Name]struct{}{},
 		Resource: map[attr.Name]struct{}{},
 	}
-	for _, il := range allInclusionLists {
+	for i, il := range allInclusionLists {
 		p.addIncludedAttributes(&matchingAttrs, attributeNames, il)
-	}
-	// if the "include" lists are empty, we use the default attributes
-	// as included
-	if len(matchingAttrs.Metric) == 0 && len(matchingAttrs.Resource) == 0 {
-		matchingAttrs = attributeNames.Default()
-	}
-	// now remove any attribute specified in the "exclude" lists
-	for _, il := range allInclusionLists {
+		// if the "include" lists are empty in the first iteration, we use the default attributes
+		// as included
+		if i == 0 && len(matchingAttrs.Metric) == 0 && len(matchingAttrs.Resource) == 0 {
+			matchingAttrs = attributeNames.Default()
+		}
+		// now remove any attribute specified in the "exclude" lists
 		p.rmExcludedAttributes(&matchingAttrs, il)
 	}
+
 	sas := Sections[[]attr.Name]{
 		Metric:   helpers.SetToSlice(matchingAttrs.Metric),
 		Resource: helpers.SetToSlice(matchingAttrs.Resource),
@@ -94,7 +93,14 @@ func (p *AttrSelector) For(metricName Name) Sections[[]attr.Name] {
 	return sas
 }
 
-func (p *AttrSelector) addIncludedAttributes(matchingAttrs *Sections[map[attr.Name]struct{}], attributeNames AttrReportGroup, inclusionLists InclusionLists) {
+// returns if the inclusion list have contents or not
+// this will be useful to decide whether to use the default
+// attribute set or not
+func (p *AttrSelector) addIncludedAttributes(
+	matchingAttrs *Sections[map[attr.Name]struct{}],
+	attributeNames AttrReportGroup,
+	inclusionLists InclusionLists,
+) {
 	allAttributes := attributeNames.All()
 	for attrName := range allAttributes.Metric {
 		if inclusionLists.includes(attrName) {

pkg/internal/export/attributes/attr_selector_test.go

@@ -51,11 +51,13 @@ func TestFor_GlobEntries(t *testing.T) {
 	p, err := NewAttrSelector(GroupKubernetes, Selection{
 		"*": InclusionLists{
 			Include: []string{"beyla_ip"},
-			Exclude: []string{"k8s_*_name"},
+			// won't be excluded from the final snapshot because they are
+			// re-included in the next inclusion list
+			Exclude: []string{"k8s_*_type"},
 		},
 		"beyla_network_flow_bytes_total": InclusionLists{
 			Include: []string{"src.*", "k8s.*"},
-			Exclude: []string{"k8s.*.type"},
+			Exclude: []string{"k8s.*.name"},
 		},
 	})
 	require.NoError(t, err)
@@ -64,8 +66,12 @@ func TestFor_GlobEntries(t *testing.T) {
 			"beyla.ip",
 			"k8s.dst.namespace",
 			"k8s.dst.node.ip",
+			"k8s.dst.owner.type",
+			"k8s.dst.type",
 			"k8s.src.namespace",
 			"k8s.src.node.ip",
+			"k8s.src.owner.type",
+			"k8s.src.type",
 			"src.address",
 			"src.name",
 			"src.port",
@@ -95,6 +101,52 @@ func TestFor_GlobEntries_NoInclusion(t *testing.T) {
 	}, p.For(BeylaNetworkFlow))
 }
 
+func TestFor_GlobEntries_Order(t *testing.T) {
+	// verify that policies are overridden from more generic to more concrete
+	p, err := NewAttrSelector(0, Selection{
+		"*": InclusionLists{
+			Include: []string{"*"},
+		},
+		"beyla_network_*": InclusionLists{
+			Exclude: []string{"dst.*", "transport", "direction", "iface"},
+		},
+		"beyla_network_flow_bytes_total": InclusionLists{
+			Include: []string{"dst.name"},
+		},
+	})
+	require.NoError(t, err)
+	assert.Equal(t, Sections[[]attr.Name]{
+		Metric: []attr.Name{
+			"beyla.ip",
+			"dst.name",
+			"src.address",
+			"src.name",
+			"src.port",
+		},
+		Resource: []attr.Name{},
+	}, p.For(BeylaNetworkFlow))
+}
+
+func TestFor_GlobEntries_Order_Default(t *testing.T) {
+	// verify that policies are overridden from more generic to more concrete
+	p, err := NewAttrSelector(0, Selection{
+		"*": InclusionLists{}, // assuming default set
+		"http_*": InclusionLists{
+			Exclude: []string{"*"},
+		},
+		"http_server_request_duration": InclusionLists{
+			Include: []string{"url.path"},
+		},
+	})
+	require.NoError(t, err)
+	assert.Equal(t, Sections[[]attr.Name]{
+		Metric: []attr.Name{
+			"url.path",
+		},
+		Resource: []attr.Name{},
+	}, p.For(HTTPServerDuration))
+}
+
 func TestFor_KubeDisabled(t *testing.T) {
 	p, err := NewAttrSelector(0, Selection{
 		"beyla_network_flow_bytes_total": InclusionLists{