Moving stats variable escaping to its own file.

go/stats/counters_test.go

@@ -21,6 +21,7 @@ import (
 	"math/rand"
 	"reflect"
 	"sort"
+	"strings"
 	"testing"
 	"time"
 )
@@ -97,17 +98,21 @@ func TestMultiCountersDot(t *testing.T) {
 	c.Add([]string{"c1.a", "c1b"}, 1)
 	c.Add([]string{"c2a", "c2.b"}, 1)
 	c.Add([]string{"c2a", "c2.b"}, 1)
-	want1 := `{"c1_a.c1b": 1, "c2a.c2_b": 2}`
-	want2 := `{"c2a.c2_b": 2, "c1_a.c1b": 1}`
+	c1a := safeLabel("c1.a")
+	c1aJSON := strings.Replace(c1a, "\\", "\\\\", -1)
+	c2b := safeLabel("c2.b")
+	c2bJSON := strings.Replace(c2b, "\\", "\\\\", -1)
+	want1 := `{"` + c1aJSON + `.c1b": 1, "c2a.` + c2bJSON + `": 2}`
+	want2 := `{"c2a.` + c2bJSON + `": 2, "` + c1aJSON + `.c1b": 1}`
 	if s := c.String(); s != want1 && s != want2 {
 		t.Errorf("want %s or %s, got %s", want1, want2, s)
 	}
 	counts := c.Counts()
-	if counts["c1_a.c1b"] != 1 {
-		t.Errorf("want 1, got %d", counts["c1_a.c1b"])
+	if counts[c1a+".c1b"] != 1 {
+		t.Errorf("want 1, got %d", counts[c1a+".c1b"])
 	}
-	if counts["c2a.c2_b"] != 2 {
-		t.Errorf("want 2, got %d", counts["c2a.c2_b"])
+	if counts["c2a."+c2b] != 2 {
+		t.Errorf("want 2, got %d", counts["c2a."+c2b])
 	}
 }
 

go/stats/safe_label.go

@@ -0,0 +1,27 @@
+/*
+Copyright 2018 Google Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package stats
+
+import (
+	"strings"
+)
+
+// safeLabel turns a label into a safe label for stats export.
+// It is in its own file so it can be customized.
+func safeLabel(label string) string {
+	return strings.Replace(label, ".", "_", -1)
+}

go/stats/timings.go

@@ -209,11 +209,12 @@ func (mt *MultiTimings) Labels() []string {
 }
 
 // safeJoinLabels joins the label values with ".", but first replaces any existing
-// "." characters in the labels with "_" to avoid issues parsing them apart later.
+// "." characters in the labels with the proper replacement, to avoid issues parsing
+// them apart later.
 func safeJoinLabels(labels []string) string {
-	sanitizedLabels := make([]string, len(labels), len(labels))
+	sanitizedLabels := make([]string, len(labels))
 	for idx, label := range labels {
-		sanitizedLabels[idx] = strings.Replace(label, ".", "_", -1)
+		sanitizedLabels[idx] = safeLabel(label)
 	}
 	return strings.Join(sanitizedLabels, ".")
 }

go/stats/timings_test.go

@@ -18,6 +18,7 @@ package stats
 
 import (
 	"expvar"
+	"strings"
 	"testing"
 	"time"
 )
@@ -50,7 +51,9 @@ func TestMultiTimingsDot(t *testing.T) {
 	clear()
 	mtm := NewMultiTimings("maptimings2", "help", []string{"label"})
 	mtm.Add([]string{"value.dot"}, 500*time.Microsecond)
-	want := `{"TotalCount":1,"TotalTime":500000,"Histograms":{"value_dot":{"500000":1,"1000000":1,"5000000":1,"10000000":1,"50000000":1,"100000000":1,"500000000":1,"1000000000":1,"5000000000":1,"10000000000":1,"inf":1,"Count":1,"Time":500000}}}`
+	safe := safeLabel("value.dot")
+	safeJSON := strings.Replace(safe, "\\", "\\\\", -1)
+	want := `{"TotalCount":1,"TotalTime":500000,"Histograms":{"` + safeJSON + `":{"500000":1,"1000000":1,"5000000":1,"10000000":1,"50000000":1,"100000000":1,"500000000":1,"1000000000":1,"5000000000":1,"10000000000":1,"inf":1,"Count":1,"Time":500000}}}`
 	if got := mtm.String(); got != want {
 		t.Errorf("got %s, want %s", got, want)
 	}