feat(rancher): added constraint management for rancher provider

docs/toml.md

@@ -117,6 +117,7 @@ Supported backends:
 - Zookeeper
 - Etcd
 - Consul Catalog
+- Rancher
 
 Supported filters:
 

provider/rancher/rancher.go

@@ -234,6 +234,7 @@ func getenv(key, fallback string) string {
 // Provide allows the rancher provider to provide configurations to traefik
 // using the given configuration channel.
 func (p *Provider) Provide(configurationChan chan<- types.ConfigMessage, pool *safe.Pool, constraints types.Constraints) error {
+	p.Constraints = append(p.Constraints, constraints...)
 
 	safe.Go(func() {
 		operation := func() error {
@@ -485,6 +486,14 @@ func (p *Provider) serviceFilter(service rancherData) bool {
 		return false
 	}
 
+	constraintTags := strings.Split(service.Labels["traefik.tags"], ",")
+	if ok, failingConstraint := p.MatchConstraints(constraintTags); !ok {
+		if failingConstraint != nil {
+			log.Debugf("Filtering service %s with constraint %s", service.Name, failingConstraint.String())
+		}
+		return false
+	}
+
 	// Only filter services by Health (HealthState) and State if EnableServiceHealthFilter is true
 	if p.EnableServiceHealthFilter {
 

provider/rancher/rancher_test.go

@@ -15,6 +15,9 @@ func TestRancherServiceFilter(t *testing.T) {
 		EnableServiceHealthFilter: true,
 	}
 
+	constraint, _ := types.NewConstraint("tag==ch*se")
+	provider.Constraints = types.Constraints{constraint}
+
 	services := []struct {
 		service  rancherData
 		expected bool
@@ -54,6 +57,7 @@ func TestRancherServiceFilter(t *testing.T) {
 		{
 			service: rancherData{
 				Labels: map[string]string{
+					"traefik.tags":   "not-cheesy",
 					"traefik.port":   "80",
 					"traefik.enable": "true",
 				},
@@ -65,6 +69,7 @@ func TestRancherServiceFilter(t *testing.T) {
 		{
 			service: rancherData{
 				Labels: map[string]string{
+					"traefik.tags":   "cheese",
 					"traefik.port":   "80",
 					"traefik.enable": "true",
 				},
@@ -76,6 +81,7 @@ func TestRancherServiceFilter(t *testing.T) {
 		{
 			service: rancherData{
 				Labels: map[string]string{
+					"traefik.tags":   "cheeeeese",
 					"traefik.port":   "80",
 					"traefik.enable": "true",
 				},
@@ -84,6 +90,18 @@ func TestRancherServiceFilter(t *testing.T) {
 			},
 			expected: true,
 		},
+		{
+			service: rancherData{
+				Labels: map[string]string{
+					"traefik.tags":   "chose",
+					"traefik.port":   "80",
+					"traefik.enable": "true",
+				},
+				Health: "healthy",
+				State:  "active",
+			},
+			expected: true,
+		},
 	}
 
 	for _, e := range services {

traefik.sample.toml

@@ -1081,6 +1081,12 @@
 # Required
 # SecretKey = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
 
+# Constraints
+#
+# Optional
+#
+# constraints = ["tag==api", "tag==chee*e"]
+# Matching with containers having this tag: "traefik.tags=cheese,wine"
 
 ################################################################
 # DynamoDB configuration backend