Handle properly deleting multiple metrics, update tests

Signed-off-by: Zach Stone <zach@giantswarm.io>

prometheus/vec.go

@@ -82,11 +82,11 @@ func (m *MetricVec) DeleteLabelValues(lvs ...string) bool {
 
 // DeletePartialMatchLabelValues removes the metric where the variable labels
 // contain all of the values passed. The order of the passed values does not matter.
-// It returns true if a metric was deleted.
+// It returns the number of metrics deleted.
 
 // This method deletes a metric if the given value is present for any label.
 // To delete a metric based on a partial match for a particular label, use DeletePartialMatch().
-func (m *MetricVec) DeletePartialMatchLabelValues(lvs ...string) bool {
+func (m *MetricVec) DeletePartialMatchLabelValues(lvs ...string) int {
 	return m.metricMap.deleteByLabelValues(lvs)
 }
 
@@ -111,11 +111,11 @@ func (m *MetricVec) Delete(labels Labels) bool {
 
 // DeletePartialMatch deletes the metric where the variable labels contains all of those
 // passed in as labels. The order of the labels does not matter.
-// It returns true if a metric was deleted.
+// It returns the number of metrics deleted.
 
 // This method deletes a metric if the given label: value pair is found in that metric.
 // To delete a metric if a particular value is found associated with any label, use DeletePartialMatchLabelValues().
-func (m *MetricVec) DeletePartialMatch(labels Labels) bool {
+func (m *MetricVec) DeletePartialMatch(labels Labels) int {
 	return m.metricMap.deleteByLabels(labels)
 }
 
@@ -374,21 +374,23 @@ func (m *metricMap) deleteByHashWithLabelValues(
 }
 
 // deleteByLabelValues deletes a metric if the given values (lvs) are present in the metric.
-func (m *metricMap) deleteByLabelValues(lvs []string) bool {
+func (m *metricMap) deleteByLabelValues(lvs []string) int {
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
+	var numDeleted int
+
 	for h, metrics := range m.metrics {
 		i := findMetricWithPartialLabelValues(metrics, lvs)
 		if i >= len(metrics) {
 			// Didn't find matching label values in this metric slice.
 			continue
 		}
 		delete(m.metrics, h)
-		return true
+		numDeleted++
 	}
 
-	return false
+	return numDeleted
 }
 
 // findMetricWithPartialLabelValues returns the index of the matching metric or
@@ -445,21 +447,23 @@ func (m *metricMap) deleteByHashWithLabels(
 }
 
 // deleteByLabels deletes a metric if the given labels are present in the metric.
-func (m *metricMap) deleteByLabels(labels Labels) bool {
+func (m *metricMap) deleteByLabels(labels Labels) int {
 	m.mtx.Lock()
 	defer m.mtx.Unlock()
 
+	var numDeleted int
+
 	for h, metrics := range m.metrics {
 		i := findMetricWithPartialLabels(m.desc, metrics, labels)
 		if i >= len(metrics) {
 			// Didn't find matching labels in this metric slice.
 			continue
 		}
 		delete(m.metrics, h)
-		return true
+		numDeleted++
 	}
 
-	return false
+	return numDeleted
 }
 
 // findMetricWithPartialLabel returns the index of the matching metric or

prometheus/vec_test.go

@@ -138,33 +138,47 @@ func TestDeletePartialMatch(t *testing.T) {
 
 func testDeletePartialMatch(t *testing.T, vec *GaugeVec) {
 	// No metric value is set.
-	if got, want := vec.DeletePartialMatch(Labels{"l1": "v1", "l2": "v2"}), false; got != want {
+	if got, want := vec.DeletePartialMatch(Labels{"l1": "v1", "l2": "v2"}), 0; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	c1 := vec.MustCurryWith(Labels{"l1": "v1"})
 	c1.WithLabelValues("2").Inc()
 
 	// Try to delete nonexistent label lx with existent value v1.
-	if got, want := c1.DeletePartialMatch(Labels{"lx": "v1"}), false; got != want {
+	if got, want := c1.DeletePartialMatch(Labels{"lx": "v1"}), 0; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	// Delete with valid pair l1: v1.
-	if got, want := c1.DeletePartialMatch(Labels{"l1": "v1"}), true; got != want {
+	if got, want := c1.DeletePartialMatch(Labels{"l1": "v1"}), 1; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	// Try to delete with partially invalid labels.
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Gauge).Set(42)
+	if got, want := vec.DeletePartialMatch(Labels{"l1": "v1", "l2": "xv2"}), 0; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	// Try to delete with a single valid label which matches multiple metrics.
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Gauge).Set(42)
+	vec.With(Labels{"l1": "v1", "l2": "vv22"}).(Gauge).Set(84)
+	if got, want := vec.DeletePartialMatch(Labels{"l1": "v1"}), 2; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	c2 := vec.MustCurryWith(Labels{"l2": "l2CurriedValue"})
 	c2.With(Labels{"l1": "11"}).Inc()
+
 	// Delete with valid curried pair l2: l2CurriedValue.
-	if got, want := c2.DeletePartialMatch(Labels{"l2": "l2CurriedValue"}), true; got != want {
+	if got, want := c2.DeletePartialMatch(Labels{"l2": "l2CurriedValue"}), 1; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	// Same labels, value matches.
 	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Gauge).Set(42)
-	if got, want := vec.DeletePartialMatch(Labels{"l1": "v1"}), true; got != want {
+	if got, want := vec.DeletePartialMatch(Labels{"l1": "v1"}), 1; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 }
@@ -182,32 +196,39 @@ func TestDeletePartialMatchLabelValues(t *testing.T) {
 
 func testDeletePartialMatchLabelValues(t *testing.T, vec *GaugeVec) {
 	// No metric value is set.
-	if got, want := vec.DeletePartialMatchLabelValues("v1", "v2"), false; got != want {
+	if got, want := vec.DeletePartialMatchLabelValues("v1", "v2"), 0; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	// Try to delete with a single valid value.
 	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Gauge).Set(42)
-	if got, want := vec.DeletePartialMatchLabelValues("v1"), true; got != want {
+	if got, want := vec.DeletePartialMatchLabelValues("v1"), 1; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	// Try to delete with partially invalid values.
 	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Gauge).Set(42)
-	if got, want := vec.DeletePartialMatchLabelValues("v1", "xv2"), false; got != want {
+	if got, want := vec.DeletePartialMatchLabelValues("v1", "xv2"), 0; got != want {
+		t.Errorf("got %v, want %v", got, want)
+	}
+
+	// Try to delete with a single valid value which matches multiple metrics.
+	vec.With(Labels{"l1": "v1", "l2": "v2"}).(Gauge).Set(42)
+	vec.With(Labels{"l1": "v1", "l2": "vv22"}).(Gauge).Set(84)
+	if got, want := vec.DeletePartialMatchLabelValues("v1"), 2; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	c1 := vec.MustCurryWith(Labels{"l1": "cv1"})
 	c1.WithLabelValues("2").Inc()
 
 	// Try to delete with nonexistent value z1.
-	if got, want := c1.DeletePartialMatchLabelValues("z1"), false; got != want {
+	if got, want := c1.DeletePartialMatchLabelValues("z1"), 0; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 
 	// Delete with valid curried value cv1.
-	if got, want := c1.DeletePartialMatchLabelValues("cv1"), true; got != want {
+	if got, want := c1.DeletePartialMatchLabelValues("cv1"), 1; got != want {
 		t.Errorf("got %v, want %v", got, want)
 	}
 }