From acc84a629a5752025fd26f460783cdf52f7afd30 Mon Sep 17 00:00:00 2001
From: Loren Howard <neutronstar@gmail.com>
Date: Mon, 10 Sep 2018 16:30:31 -0700
Subject: [PATCH] convert periods in tag values to underscore (#44)

---
 tags.go      | 2 +-
 tags_test.go | 8 ++++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/tags.go b/tags.go
index 972ead2..f1e50ba 100644
--- a/tags.go
+++ b/tags.go
@@ -14,7 +14,7 @@ const (
 )
 
 // illegalTagValueChars are loosely set to ensure we don't have statsd parse errors.
-var illegalTagValueChars = regexp.MustCompile(`[:|]`)
+var illegalTagValueChars = regexp.MustCompile(`[:|.]`)
 
 type tagPair struct {
 	dimension string
diff --git a/tags_test.go b/tags_test.go
index fc742a5..43379b6 100644
--- a/tags_test.go
+++ b/tags_test.go
@@ -27,3 +27,11 @@ func TestSerializeIllegalTags(t *testing.T) {
 		t.Errorf("Serialized output (%s) didn't match expected output", serialized)
 	}
 }
+
+func TestSerializeTagValuePeriod(t *testing.T) {
+	tags := map[string]string{"foo": "blah.blah", "q": "p"}
+	serialized := serializeTags(tags)
+	if serialized != ".__foo=blah_blah.__q=p" {
+		t.Errorf("Serialized output (%s) didn't match expected output", serialized)
+	}
+}