add target label

Signed-off-by: Alex Pana <8968914+acpana@users.noreply.github.com>

constraint/pkg/client/client.go

@@ -564,6 +564,15 @@ func (c *Client) Review(ctx context.Context, obj interface{}, opts ...drivers.Op
 
 		responses.ByTarget[target] = resp
 		if stats != nil {
+			// add the target label to these stats for future collation.
+			targetLabel := &instrumentation.Label{Name: "target", Value: target}
+			for _, stat := range stats {
+				if stat.Labels == nil || len(stat.Labels) == 0 {
+					stat.Labels = []*instrumentation.Label{targetLabel}
+				} else {
+					stat.Labels = append(stat.Labels, targetLabel)
+				}
+			}
 			responses.StatsEntries = append(responses.StatsEntries, stats...)
 		}
 	}

constraint/pkg/client/e2e_test.go

@@ -792,7 +792,8 @@ func TestE2E_Review_StatsEntries(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	c, err := client.NewClient(client.Targets(&handlertest.Handler{}), client.Driver(d))
+	testHandler := &handlertest.Handler{}
+	c, err := client.NewClient(client.Targets(testHandler), client.Driver(d))
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -883,6 +884,18 @@ func TestE2E_Review_StatsEntries(t *testing.T) {
 				t.Errorf("expected labels but did not find any")
 			}
 
+			foundTargetLabel := false
+			for _, label := range se.Labels {
+				if label.Name == "target" && label.Value == testHandler.GetName() {
+					foundTargetLabel = true
+					break
+				}
+			}
+
+			if !foundTargetLabel {
+				t.Fatalf("did not find target label for: %s", testHandler.GetName())
+			}
+
 			delete(kindSet, se.StatsFor)
 		} else {
 			t.Fatalf("encountered an unknown Key: %s", reflect.ValueOf(se.Scope))