feature(config): Add go-sockaddr templating support to nomad consul a…

…ddress

command/agent/config.go

@@ -20,6 +20,7 @@ import (
 	"github.com/hashicorp/go-sockaddr/template"
 	client "github.com/hashicorp/nomad/client/config"
 	"github.com/hashicorp/nomad/helper"
+	helperConfig "github.com/hashicorp/nomad/helper/config"
 	"github.com/hashicorp/nomad/nomad"
 	"github.com/hashicorp/nomad/nomad/structs"
 	"github.com/hashicorp/nomad/nomad/structs/config"
@@ -1213,7 +1214,7 @@ func (c *Config) Merge(b *Config) *Config {
 // initialized and have reasonable defaults.
 func (c *Config) normalizeAddrs() error {
 	if c.BindAddr != "" {
-		ipStr, err := parseSingleIPTemplate(c.BindAddr)
+		ipStr, err := helperConfig.ParseSingleIPTemplate(c.BindAddr)
 		if err != nil {
 			return fmt.Errorf("Bind address resolution failed: %v", err)
 		}
@@ -1308,25 +1309,6 @@ func parseSingleInterfaceTemplate(tpl string) (string, error) {
 	return out, nil
 }
 
-// parseSingleIPTemplate is used as a helper function to parse out a single IP
-// address from a config parameter.
-func parseSingleIPTemplate(ipTmpl string) (string, error) {
-	out, err := template.Parse(ipTmpl)
-	if err != nil {
-		return "", fmt.Errorf("Unable to parse address template %q: %v", ipTmpl, err)
-	}
-
-	ips := strings.Split(out, " ")
-	switch len(ips) {
-	case 0:
-		return "", errors.New("No addresses found, please configure one.")
-	case 1:
-		return ips[0], nil
-	default:
-		return "", fmt.Errorf("Multiple addresses found (%q), please configure one.", out)
-	}
-}
-
 // parseMultipleIPTemplate is used as a helper function to parse out a multiple IP
 // addresses from a config parameter.
 func parseMultipleIPTemplate(ipTmpl string) ([]string, error) {
@@ -1350,7 +1332,7 @@ func normalizeBind(addr, bind string) (string, error) {
 	if addr == "" {
 		return bind, nil
 	}
-	return parseSingleIPTemplate(addr)
+	return helperConfig.ParseSingleIPTemplate(addr)
 }
 
 // normalizeMultipleBind returns normalized bind addresses.
@@ -1376,7 +1358,7 @@ func normalizeMultipleBind(addr, bind string) ([]string, error) {
 //
 // Loopback is only considered a valid advertise address in dev mode.
 func normalizeAdvertise(addr string, bind string, defport int, dev bool) (string, error) {
-	addr, err := parseSingleIPTemplate(addr)
+	addr, err := helperConfig.ParseSingleIPTemplate(addr)
 	if err != nil {
 		return "", fmt.Errorf("Error parsing advertise address template: %v", err)
 	}
@@ -1417,7 +1399,7 @@ func normalizeAdvertise(addr string, bind string, defport int, dev bool) (string
 	}
 
 	// Bind is not localhost but not a valid advertise IP, use first private IP
-	addr, err = parseSingleIPTemplate("{{ GetPrivateIP }}")
+	addr, err = helperConfig.ParseSingleIPTemplate("{{ GetPrivateIP }}")
 	if err != nil {
 		return "", fmt.Errorf("Unable to parse default advertise address: %v", err)
 	}

helper/config/config.go

@@ -0,0 +1,28 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/hashicorp/go-sockaddr/template"
+)
+
+// ParseSingleIPTemplate is used as a helper function to parse out a single IP
+// address from a config parameter.
+func ParseSingleIPTemplate(ipTmpl string) (string, error) {
+	out, err := template.Parse(ipTmpl)
+	if err != nil {
+		return "", fmt.Errorf("unable to parse address template %q: %v", ipTmpl, err)
+	}
+
+	ips := strings.Split(out, " ")
+	switch len(ips) {
+	case 0:
+		return "", errors.New("no addresses found, please configure one")
+	case 1:
+		return strings.TrimSpace(ips[0]), nil
+	default:
+		return "", fmt.Errorf("multiple addresses found (%q), please configure one", out)
+	}
+}

nomad/structs/config/consul.go

@@ -1,12 +1,14 @@
 package config
 
 import (
+	"fmt"
 	"net/http"
 	"strings"
 	"time"
 
 	consul "github.com/hashicorp/consul/api"
 	"github.com/hashicorp/nomad/helper"
+	helperConfig "github.com/hashicorp/nomad/helper/config"
 )
 
 // ConsulConfig contains the configuration information necessary to
@@ -251,7 +253,11 @@ func (c *ConsulConfig) ApiConfig() (*consul.Config, error) {
 	// http.Transport.
 	config := consul.DefaultConfig()
 	if c.Addr != "" {
-		config.Address = c.Addr
+		ipStr, err := helperConfig.ParseSingleIPTemplate(c.Addr)
+		if err != nil {
+			return nil, fmt.Errorf("unable to parse address template %q: %v", c.Addr, err)
+		}
+		config.Address = ipStr
 	}
 	if c.Token != "" {
 		config.Token = c.Token

nomad/structs/config/consul_test.go

@@ -5,10 +5,12 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"strings"
 	"testing"
 	"time"
 
 	consulapi "github.com/hashicorp/consul/api"
+	sockaddr "github.com/hashicorp/go-sockaddr"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
@@ -167,3 +169,42 @@ func TestConsulConfig_Exec(t *testing.T) {
 	require.NotNil(t, conf.VerifySSL)
 	assert.True(t, *conf.VerifySSL)
 }
+
+func TestConsulConfig_StringAddr(t *testing.T) {
+	t.Parallel()
+
+	conf := ConsulConfig{
+		Addr: "10.0.1.0:8500",
+	}
+
+	apiConf, err := conf.ApiConfig()
+	assert.Nil(t, err)
+	assert.Equal(t, apiConf.Address, "10.0.1.0:8500")
+}
+
+func TestConsulConfig_SockAddr(t *testing.T) {
+	t.Parallel()
+
+	privateIps, err := sockaddr.GetPrivateIP()
+	if err != nil {
+		t.Fatalf("failed to get private IPs: %v", err)
+	}
+	privateIp := strings.Split(privateIps, " ")[0]
+	conf := ConsulConfig{
+		Addr: "{{ GetPrivateIP }}:8500",
+	}
+
+	apiConf, err := conf.ApiConfig()
+	assert.Nil(t, err)
+	assert.Equal(t, apiConf.Address, privateIp+":8500")
+}
+
+func TestConsulConfig_SockAddrOnlyOneIP(t *testing.T) {
+	conf := ConsulConfig{
+		Addr: "{{ GetPrivateIPs }}",
+	}
+
+	result, err := conf.ApiConfig()
+	assert.Nil(t, result)
+	assert.NotNil(t, err)
+}

website/content/docs/configuration/consul.mdx

@@ -44,6 +44,7 @@ configuring Nomad to talk to Consul via DNS such as consul.service.consul
   Consul agent, given in the format `host:port`. Supports Unix sockets with the
   format: `unix:///tmp/consul/consul.sock`. Will default to the
   `CONSUL_HTTP_ADDR` environment variable if set.
+  The value supports [go-sockaddr/template format][go-sockaddr/template].
 
 - `allow_unauthenticated` `(bool: true)` - Specifies if users submitting jobs to
   the Nomad server should be required to provide their own Consul token, proving
@@ -225,3 +226,4 @@ namespace "nomad-ns" {
 
 [consul]: https://www.consul.io/ 'Consul by HashiCorp'
 [bootstrap]: https://learn.hashicorp.com/tutorials/nomad/clustering 'Automatic Bootstrapping'
+[go-sockaddr/template]: https://godoc.org/github.com/hashicorp/go-sockaddr/template