From 1a1a9ae684bc8ace9c4a634020ba5cd42d119405 Mon Sep 17 00:00:00 2001
From: Samuel BERTHE <dev@samuel-berthe.fr>
Date: Fri, 20 Jan 2017 18:24:30 +0100
Subject: [PATCH] feat(consul,service_tags): Support escaped comma (#401)

* feat(service_tags): Support escaped comma
* test(bridge): Adds test for escaped comma in tags + fix types_test.go tests
---
 bridge/types_test.go  |  3 +++
 bridge/util.go        | 30 +++++++++++++++++++---
 bridge/util_test.go   | 59 +++++++++++++++++++++++++++++++++++++++++++
 docs/user/services.md |  7 +++++
 4 files changed, 96 insertions(+), 3 deletions(-)
 create mode 100644 bridge/util_test.go

diff --git a/bridge/types_test.go b/bridge/types_test.go
index fe2265e8e..0e3e63ef8 100644
--- a/bridge/types_test.go
+++ b/bridge/types_test.go
@@ -23,3 +23,6 @@ func (f *fakeAdapter) Deregister(service *Service) error {
 func (f *fakeAdapter) Refresh(service *Service) error {
 	return nil
 }
+func (f *fakeAdapter) Services() ([]*Service, error) {
+	return nil, nil
+}
diff --git a/bridge/util.go b/bridge/util.go
index 3b450faff..e3c295cfb 100644
--- a/bridge/util.go
+++ b/bridge/util.go
@@ -20,12 +20,36 @@ func mapDefault(m map[string]string, key, default_ string) string {
 	return v
 }
 
+// Golang regexp module does not support /(?!\\),/ syntax for spliting by not escaped comma
+// Then this function is reproducing it
+func recParseEscapedComma(str string) []string {
+	if len(str) == 0 {
+		return []string{}
+	} else if str[0] == ',' {
+		return recParseEscapedComma(str[1:])
+	}
+
+	offset := 0
+	for len(str[offset:]) > 0 {
+		index := strings.Index(str[offset:], ",")
+
+		if index == -1 {
+			break
+		} else if str[offset+index-1:offset+index] != "\\" {
+			return append(recParseEscapedComma(str[offset+index+1:]), str[:offset+index])
+		}
+
+		str = str[:offset+index-1] + str[offset+index:]
+		offset += index
+	}
+
+	return []string{str}
+}
+
 func combineTags(tagParts ...string) []string {
 	tags := make([]string, 0)
 	for _, element := range tagParts {
-		if element != "" {
-			tags = append(tags, strings.Split(element, ",")...)
-		}
+		tags = append(tags, recParseEscapedComma(element)...)
 	}
 	return tags
 }
diff --git a/bridge/util_test.go b/bridge/util_test.go
new file mode 100644
index 000000000..149186a9b
--- /dev/null
+++ b/bridge/util_test.go
@@ -0,0 +1,59 @@
+package bridge
+
+import (
+	"sort"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestEscapedComma(t *testing.T) {
+	cases := []struct {
+		Tag      string
+		Expected []string
+	}{
+		{
+			Tag:      "",
+			Expected: []string{},
+		},
+		{
+			Tag:      "foobar",
+			Expected: []string{"foobar"},
+		},
+		{
+			Tag:      "foo,bar",
+			Expected: []string{"foo", "bar"},
+		},
+		{
+			Tag:      "foo\\,bar",
+			Expected: []string{"foo,bar"},
+		},
+		{
+			Tag:      "foo,bar\\,baz",
+			Expected: []string{"foo", "bar,baz"},
+		},
+		{
+			Tag:      "\\,foobar\\,",
+			Expected: []string{",foobar,"},
+		},
+		{
+			Tag:      ",,,,foo,,,bar,,,",
+			Expected: []string{"foo", "bar"},
+		},
+		{
+			Tag:      ",,,,",
+			Expected: []string{},
+		},
+		{
+			Tag:      ",,\\,,",
+			Expected: []string{","},
+		},
+	}
+
+	for _, c := range cases {
+		results := recParseEscapedComma(c.Tag)
+		sort.Strings(c.Expected)
+		sort.Strings(results)
+		assert.EqualValues(t, c.Expected, results)
+	}
+}
diff --git a/docs/user/services.md b/docs/user/services.md
index d7a187c1e..5065b9739 100644
--- a/docs/user/services.md
+++ b/docs/user/services.md
@@ -166,6 +166,13 @@ Results in `Service`:
 
 Keep in mind not all of the `Service` object may be used by the registry backend. For example, currently none of them support registering arbitrary attributes. This field is there for future use.
 
+The comma can be escaped by adding a backslash, such as the following example:
+
+    $ docker run -d --name redis.0 -p 10000:6379 \
+        -e "SERVICE_NAME=db" \
+        -e "SERVICE_TAGS=/(;\\,:-_)/" \
+        -e "SERVICE_REGION=us2" progrium/redis
+
 ### Multiple services with defaults
 
 	$ docker run -d --name nginx.0 -p 4443:443 -p 8000:80 progrium/nginx