From 2e126a52f2df46950f48abe9067c9fad0175899d Mon Sep 17 00:00:00 2001
From: Benjamin Boudreau <boudreau.benjamin@gmail.com>
Date: Thu, 23 Mar 2017 19:38:17 -0400
Subject: [PATCH] Adding support for dns in stack files

Signed-off-by: Benjamin Boudreau <boudreau.benjamin@gmail.com>
---
 compose/convert/service.go      | 16 ++++++++++++++
 compose/convert/service_test.go | 39 +++++++++++++++++++++++++++++++++
 compose/types/types.go          |  2 --
 3 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/compose/convert/service.go b/compose/convert/service.go
index 497dbe004f..cd982b6571 100644
--- a/compose/convert/service.go
+++ b/compose/convert/service.go
@@ -93,6 +93,11 @@ func convertService(
 		return swarm.ServiceSpec{}, err
 	}
 
+	dnsConfig, err := convertDNSConfig(service.DNS, service.DNSSearch)
+	if err != nil {
+		return swarm.ServiceSpec{}, err
+	}
+
 	var logDriver *swarm.Driver
 	if service.Logging != nil {
 		logDriver = &swarm.Driver{
@@ -113,6 +118,7 @@ func convertService(
 				Args:            service.Command,
 				Hostname:        service.Hostname,
 				Hosts:           sortStrings(convertExtraHosts(service.ExtraHosts)),
+				DNSConfig:       dnsConfig,
 				Healthcheck:     healthcheck,
 				Env:             sortStrings(convertEnvironment(service.Environment)),
 				Labels:          AddStackLabel(namespace, service.Labels),
@@ -425,3 +431,13 @@ func convertDeployMode(mode string, replicas *uint64) (swarm.ServiceMode, error)
 	}
 	return serviceMode, nil
 }
+
+func convertDNSConfig(DNS []string, DNSSearch []string) (*swarm.DNSConfig, error) {
+	if DNS != nil || DNSSearch != nil {
+		return &swarm.DNSConfig{
+			Nameservers: DNS,
+			Search:      DNSSearch,
+		}, nil
+	}
+	return nil, nil
+}
diff --git a/compose/convert/service_test.go b/compose/convert/service_test.go
index 352e9a61b5..91af572994 100644
--- a/compose/convert/service_test.go
+++ b/compose/convert/service_test.go
@@ -277,3 +277,42 @@ func (s byTargetSort) Less(i, j int) bool {
 func (s byTargetSort) Swap(i, j int) {
 	s[i], s[j] = s[j], s[i]
 }
+
+func TestConvertDNSConfigEmpty(t *testing.T) {
+	dnsConfig, err := convertDNSConfig(nil, nil)
+
+	assert.NilError(t, err)
+	assert.Equal(t, dnsConfig, (*swarm.DNSConfig)(nil))
+}
+
+var (
+	nameservers = []string{"8.8.8.8", "9.9.9.9"}
+	search      = []string{"dc1.example.com", "dc2.example.com"}
+)
+
+func TestConvertDNSConfigAll(t *testing.T) {
+	dnsConfig, err := convertDNSConfig(nameservers, search)
+	assert.NilError(t, err)
+	assert.DeepEqual(t, dnsConfig, &swarm.DNSConfig{
+		Nameservers: nameservers,
+		Search:      search,
+	})
+}
+
+func TestConvertDNSConfigNameservers(t *testing.T) {
+	dnsConfig, err := convertDNSConfig(nameservers, nil)
+	assert.NilError(t, err)
+	assert.DeepEqual(t, dnsConfig, &swarm.DNSConfig{
+		Nameservers: nameservers,
+		Search:      nil,
+	})
+}
+
+func TestConvertDNSConfigSearch(t *testing.T) {
+	dnsConfig, err := convertDNSConfig(nil, search)
+	assert.NilError(t, err)
+	assert.DeepEqual(t, dnsConfig, &swarm.DNSConfig{
+		Nameservers: nil,
+		Search:      search,
+	})
+}
diff --git a/compose/types/types.go b/compose/types/types.go
index 19500e195d..ced12deb6d 100644
--- a/compose/types/types.go
+++ b/compose/types/types.go
@@ -11,8 +11,6 @@ var UnsupportedProperties = []string{
 	"cap_drop",
 	"cgroup_parent",
 	"devices",
-	"dns",
-	"dns_search",
 	"domainname",
 	"external_links",
 	"ipc",