Merge pull request #274 from samber/consul-catalog-with-tags-settings

feat(traefik,consul-catalog): Set attributes from consul catalog tags (loadbalancer,circuitbreaker,weight)

cmd.go

@@ -142,6 +142,7 @@ func init() {
 	traefikCmd.PersistentFlags().BoolVar(&arguments.consulCatalog, "consulCatalog", false, "Enable Consul catalog backend")
 	traefikCmd.PersistentFlags().StringVar(&arguments.ConsulCatalog.Domain, "consulCatalog.domain", "", "Default domain used")
 	traefikCmd.PersistentFlags().StringVar(&arguments.ConsulCatalog.Endpoint, "consulCatalog.endpoint", "127.0.0.1:8500", "Consul server endpoint")
+	traefikCmd.PersistentFlags().StringVar(&arguments.ConsulCatalog.Prefix, "consulCatalog.prefix", "traefik", "Consul catalog tag prefix")
 
 	traefikCmd.PersistentFlags().BoolVar(&arguments.zookeeper, "zookeeper", false, "Enable Zookeeper backend")
 	traefikCmd.PersistentFlags().BoolVar(&arguments.Zookeeper.Watch, "zookeeper.watch", true, "Watch provider")

docs/toml.md

@@ -675,11 +675,26 @@ endpoint = "127.0.0.1:8500"
 # Optional
 #
 domain = "consul.localhost"
+
+# Prefix for Consul catalog tags
+#
+# Optional
+#
+prefix = "traefik"
 ```
 
 This backend will create routes matching on hostname based on the service name
 used in consul.
 
+Additional settings can be defined using Consul Catalog tags:
+- ```traefik.enable=false```: disable this container in Træfɪk
+- ```traefik.protocol=https```: override the default `http` protocol
+- ```traefik.backend.weight=10```: assign this weight to the container
+- ```traefik.backend.circuitbreaker=NetworkErrorRatio() > 0.5```
+- ```traefik.backend.loadbalancer=drr```: override the default load balancing mode
+- ```traefik.frontend.rule=Host:test.traefik.io```: override the default frontend rule (Default: `Host:{containerName}.{domain}`). See [frontends](#frontends).
+- ```traefik.frontend.passHostHeader=true```: forward client `Host` header to the backend.
+- ```traefik.frontend.entryPoints=http,https```: assign this frontend to entry points `http` and `https`. Overrides `defaultEntryPoints`.
 
 ## Etcd backend
 

integration/consul_catalog_test.go

@@ -39,7 +39,7 @@ func (s *ConsulCatalogSuite) SetUpSuite(c *check.C) {
 	time.Sleep(2000 * time.Millisecond)
 }
 
-func (s *ConsulCatalogSuite) registerService(name string, address string, port int) error {
+func (s *ConsulCatalogSuite) registerService(name string, address string, port int, tags []string) error {
 	catalog := s.consulClient.Catalog()
 	_, err := catalog.Register(
 		&api.CatalogRegistration{
@@ -50,6 +50,7 @@ func (s *ConsulCatalogSuite) registerService(name string, address string, port i
 				Service: name,
 				Address: address,
 				Port:    port,
+				Tags:    tags,
 			},
 		},
 		&api.WriteOptions{},
@@ -93,7 +94,7 @@ func (s *ConsulCatalogSuite) TestSingleService(c *check.C) {
 
 	nginx := s.composeProject.Container(c, "nginx")
 
-	err = s.registerService("test", nginx.NetworkSettings.IPAddress, 80)
+	err = s.registerService("test", nginx.NetworkSettings.IPAddress, 80, []string{})
 	c.Assert(err, checker.IsNil, check.Commentf("Error registering service"))
 	defer s.deregisterService("test", nginx.NetworkSettings.IPAddress)
 

provider/consul_catalog.go

@@ -16,6 +16,8 @@ import (
 const (
 	// DefaultWatchWaitTime is the duration to wait when polling consul
 	DefaultWatchWaitTime = 15 * time.Second
+	// DefaultConsulCatalogTagPrefix is a prefix for additional service/node configurations
+	DefaultConsulCatalogTagPrefix = "traefik"
 )
 
 // ConsulCatalog holds configurations of the Consul catalog provider.
@@ -24,10 +26,16 @@ type ConsulCatalog struct {
 	Endpoint     string
 	Domain       string
 	client       *api.Client
+	Prefix       string
+}
+
+type serviceUpdate struct {
+	ServiceName string
+	Attributes  []string
 }
 
 type catalogUpdate struct {
-	Service string
+	Service *serviceUpdate
 	Nodes   []*api.ServiceEntry
 }
 
@@ -79,41 +87,76 @@ func (provider *ConsulCatalog) healthyNodes(service string) (catalogUpdate, erro
 		return catalogUpdate{}, err
 	}
 
+	set := map[string]bool{}
+	tags := []string{}
+	for _, node := range data {
+		for _, tag := range node.Service.Tags {
+			if _, ok := set[tag]; ok == false {
+				set[tag] = true
+				tags = append(tags, tag)
+			}
+		}
+	}
+
 	return catalogUpdate{
-		Service: service,
-		Nodes:   data,
+		Service: &serviceUpdate{
+			ServiceName: service,
+			Attributes:  tags,
+		},
+		Nodes: data,
 	}, nil
 }
 
+func (provider *ConsulCatalog) getEntryPoints(list string) []string {
+	return strings.Split(list, ",")
+}
+
 func (provider *ConsulCatalog) getBackend(node *api.ServiceEntry) string {
 	return strings.ToLower(node.Service.Service)
 }
 
-func (provider *ConsulCatalog) getFrontendValue(service string) string {
-	return "Host:" + service + "." + provider.Domain
+func (provider *ConsulCatalog) getFrontendRule(service serviceUpdate) string {
+	customFrontendRule := provider.getAttribute("frontend.rule", service.Attributes, "")
+	if customFrontendRule != "" {
+		return customFrontendRule
+	}
+	return "Host:" + service.ServiceName + "." + provider.Domain
+}
+
+func (provider *ConsulCatalog) getAttribute(name string, tags []string, defaultValue string) string {
+	for _, tag := range tags {
+		if strings.Index(tag, DefaultConsulCatalogTagPrefix+".") == 0 {
+			if kv := strings.SplitN(tag[len(DefaultConsulCatalogTagPrefix+"."):], "=", 2); len(kv) == 2 && kv[0] == name {
+				return kv[1]
+			}
+		}
+	}
+	return defaultValue
 }
 
 func (provider *ConsulCatalog) buildConfig(catalog []catalogUpdate) *types.Configuration {
 	var FuncMap = template.FuncMap{
-		"getBackend":       provider.getBackend,
-		"getFrontendValue": provider.getFrontendValue,
-		"replace":          replace,
+		"getBackend":      provider.getBackend,
+		"getFrontendRule": provider.getFrontendRule,
+		"getAttribute":    provider.getAttribute,
+		"getEntryPoints":  provider.getEntryPoints,
+		"replace":         replace,
 	}
 
 	allNodes := []*api.ServiceEntry{}
-	serviceNames := []string{}
+	services := []*serviceUpdate{}
 	for _, info := range catalog {
 		if len(info.Nodes) > 0 {
-			serviceNames = append(serviceNames, info.Service)
+			services = append(services, info.Service)
 			allNodes = append(allNodes, info.Nodes...)
 		}
 	}
 
 	templateObjects := struct {
-		Services []string
+		Services []*serviceUpdate
 		Nodes    []*api.ServiceEntry
 	}{
-		Services: serviceNames,
+		Services: services,
 		Nodes:    allNodes,
 	}
 

provider/consul_catalog_test.go

@@ -14,17 +14,68 @@ func TestConsulCatalogGetFrontendRule(t *testing.T) {
 	}
 
 	services := []struct {
-		service  string
+		service  serviceUpdate
 		expected string
 	}{
 		{
-			service:  "foo",
+			service: serviceUpdate{
+				ServiceName: "foo",
+				Attributes:  []string{},
+			},
 			expected: "Host:foo.localhost",
 		},
+		{
+			service: serviceUpdate{
+				ServiceName: "foo",
+				Attributes: []string{
+					"traefik.frontend.rule=Host:*.example.com",
+				},
+			},
+			expected: "Host:*.example.com",
+		},
 	}
 
 	for _, e := range services {
-		actual := provider.getFrontendValue(e.service)
+		actual := provider.getFrontendRule(e.service)
+		if actual != e.expected {
+			t.Fatalf("expected %q, got %q", e.expected, actual)
+		}
+	}
+}
+
+func TestConsulCatalogGetAttribute(t *testing.T) {
+	provider := &ConsulCatalog{
+		Domain: "localhost",
+	}
+
+	services := []struct {
+		tags         []string
+		key          string
+		defaultValue string
+		expected     string
+	}{
+		{
+			tags: []string{
+				"foo.bar=ramdom",
+				"traefik.backend.weight=42",
+			},
+			key:          "backend.weight",
+			defaultValue: "",
+			expected:     "42",
+		},
+		{
+			tags: []string{
+				"foo.bar=ramdom",
+				"traefik.backend.wei=42",
+			},
+			key:          "backend.weight",
+			defaultValue: "",
+			expected:     "",
+		},
+	}
+
+	for _, e := range services {
+		actual := provider.getAttribute(e.key, e.tags, e.defaultValue)
 		if actual != e.expected {
 			t.Fatalf("expected %q, got %q", e.expected, actual)
 		}
@@ -49,7 +100,10 @@ func TestConsulCatalogBuildConfig(t *testing.T) {
 		{
 			nodes: []catalogUpdate{
 				{
-					Service: "test",
+					Service: &serviceUpdate{
+						ServiceName: "test",
+						Attributes:  []string{},
+					},
 				},
 			},
 			expectedFrontends: map[string]*types.Frontend{},
@@ -58,13 +112,26 @@ func TestConsulCatalogBuildConfig(t *testing.T) {
 		{
 			nodes: []catalogUpdate{
 				{
-					Service: "test",
+					Service: &serviceUpdate{
+						ServiceName: "test",
+						Attributes: []string{
+							"traefik.backend.loadbalancer=drr",
+							"traefik.backend.circuitbreaker=NetworkErrorRatio() > 0.5",
+							"random.foo=bar",
+						},
+					},
 					Nodes: []*api.ServiceEntry{
 						{
 							Service: &api.AgentService{
 								Service: "test",
 								Address: "127.0.0.1",
 								Port:    80,
+								Tags: []string{
+									"traefik.backend.weight=42",
+									"random.foo=bar",
+									"traefik.backend.passHostHeader=true",
+									"traefik.protocol=https",
+								},
 							},
 							Node: &api.Node{
 								Node:    "localhost",
@@ -88,11 +155,16 @@ func TestConsulCatalogBuildConfig(t *testing.T) {
 				"backend-test": {
 					Servers: map[string]types.Server{
 						"test--127-0-0-1--80": {
-							URL: "http://127.0.0.1:80",
+							URL:    "https://127.0.0.1:80",
+							Weight: 42,
 						},
 					},
-					CircuitBreaker: nil,
-					LoadBalancer:   nil,
+					CircuitBreaker: &types.CircuitBreaker{
+						Expression: "NetworkErrorRatio() > 0.5",
+					},
+					LoadBalancer: &types.LoadBalancer{
+						Method: "drr",
+					},
 				},
 			},
 		},

templates/consul_catalog.tmpl

@@ -1,12 +1,40 @@
-[backends]{{range .Nodes}}
+[backends]
+{{range .Nodes}}
+  {{if ne (getAttribute "enable" .Service.Tags "true") "false"}}
     [backends.backend-{{getBackend .}}.servers.{{.Service.Service | replace "." "-"}}--{{.Service.Address | replace "." "-"}}--{{.Service.Port}}]
-    url = "http://{{.Service.Address}}:{{.Service.Port}}"
+      url = "{{getAttribute "protocol" .Service.Tags "http"}}://{{.Service.Address}}:{{.Service.Port}}"
+      {{$weight := getAttribute "backend.weight" .Service.Tags ""}}
+      {{with $weight}}
+        weight = {{$weight}}
+      {{end}}
+    {{end}}
+{{end}}
+
+{{range .Services}}
+  {{$service := .ServiceName}}
+  {{$circuitBreaker := getAttribute "backend.circuitbreaker" .Attributes ""}}
+  {{with $circuitBreaker}}
+  [backends.backend-{{$service}}.circuitbreaker]
+    expression = "{{$circuitBreaker}}"
+  {{end}}
+
+  {{$loadBalancer := getAttribute "backend.loadbalancer" .Attributes ""}}
+  {{with $loadBalancer}}
+  [backends.backend-{{$service}}.loadbalancer]
+    method = "{{$loadBalancer}}"
+  {{end}}
 {{end}}
 
 [frontends]{{range .Services}}
-  [frontends.frontend-{{.}}]
-  backend = "backend-{{.}}"
-  passHostHeader = false
-    [frontends.frontend-{{.}}.routes.route-host-{{.}}]
-    rule = "{{getFrontendValue .}}"
+  [frontends.frontend-{{.ServiceName}}]
+  backend = "backend-{{.ServiceName}}"
+  passHostHeader = {{getAttribute "frontend.passHostHeader" .Attributes "false"}}
+  {{$entryPoints := getAttribute "frontend.entrypoints" .Attributes ""}}
+  {{with $entryPoints}}
+    entrypoints = [{{range getEntryPoints $entryPoints}}
+      "{{.}}",
+    {{end}}]
+  {{end}}
+  [frontends.frontend-{{.ServiceName}}.routes.route-host-{{.ServiceName}}]
+    rule = "{{getFrontendRule .}}"
 {{end}}