add go-sockaddr templating support to nomad consul address (#12084)

.changelog/12084.txt

+```release-note:improvement
+consul: add go-sockaddr templating support to nomad consul address
+```

command/agent/config.go

@@ -16,6 +16,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/hashicorp/go-secure-stdlib/listenerutil"
 	sockaddr "github.com/hashicorp/go-sockaddr"
 	"github.com/hashicorp/go-sockaddr/template"
 	client "github.com/hashicorp/nomad/client/config"
@@ -1230,7 +1231,7 @@ 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 := listenerutil.ParseSingleIPTemplate(c.BindAddr)
 		if err != nil {
 			return fmt.Errorf("Bind address resolution failed: %v", err)
 		}
@@ -1325,25 +1326,6 @@ 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) {
@@ -1367,7 +1349,7 @@ func normalizeBind(addr, bind string) (string, error) {
 	if addr == "" {
 		return bind, nil
 	}
-	return parseSingleIPTemplate(addr)
+	return listenerutil.ParseSingleIPTemplate(addr)
 }
 
 // normalizeMultipleBind returns normalized bind addresses.
@@ -1393,7 +1375,7 @@ 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 := listenerutil.ParseSingleIPTemplate(addr)
 	if err != nil {
 		return "", fmt.Errorf("Error parsing advertise address template: %v", err)
 	}
@@ -1434,7 +1416,7 @@ 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 = listenerutil.ParseSingleIPTemplate("{{ GetPrivateIP }}")
 	if err != nil {
 		return "", fmt.Errorf("Unable to parse default advertise address: %v", err)
 	}

go.mod

@@ -64,6 +64,7 @@ require (
 	github.com/hashicorp/go-msgpack v1.1.5
 	github.com/hashicorp/go-multierror v1.1.1
 	github.com/hashicorp/go-plugin v1.4.3
+	github.com/hashicorp/go-secure-stdlib/listenerutil v0.1.4
 	github.com/hashicorp/go-sockaddr v1.0.2
 	github.com/hashicorp/go-syslog v1.0.0
 	github.com/hashicorp/go-uuid v1.0.2
@@ -86,7 +87,7 @@ require (
 	github.com/kr/text v0.2.0
 	github.com/mattn/go-colorable v0.1.9
 	github.com/miekg/dns v1.1.26
-	github.com/mitchellh/cli v1.1.0
+	github.com/mitchellh/cli v1.1.2
 	github.com/mitchellh/colorstring v0.0.0-20150917214807-8631ce90f286
 	github.com/mitchellh/copystructure v1.2.0
 	github.com/mitchellh/go-glint v0.0.0-20210722152315-6515ceb4a127
@@ -143,6 +144,9 @@ require (
 	github.com/Azure/go-autorest/tracing v0.6.0 // indirect
 	github.com/BurntSushi/toml v0.4.1 // indirect
 	github.com/DataDog/datadog-go v3.2.0+incompatible // indirect
+	github.com/Masterminds/goutils v1.1.0 // indirect
+	github.com/Masterminds/semver v1.5.0 // indirect
+	github.com/Masterminds/sprig v2.22.0+incompatible // indirect
 	github.com/Microsoft/hcsshim v0.8.23 // indirect
 	github.com/VividCortex/ewma v1.1.1 // indirect
 	github.com/agext/levenshtein v1.2.1 // indirect
@@ -197,9 +201,16 @@ require (
 	github.com/hashicorp/go-retryablehttp v0.6.7 // indirect
 	github.com/hashicorp/go-rootcerts v1.0.2 // indirect
 	github.com/hashicorp/go-safetemp v1.0.0 // indirect
+	github.com/hashicorp/go-secure-stdlib/parseutil v0.1.1 // indirect
+	github.com/hashicorp/go-secure-stdlib/reloadutil v0.1.1 // indirect
+	github.com/hashicorp/go-secure-stdlib/strutil v0.1.1 // indirect
+	github.com/hashicorp/go-secure-stdlib/tlsutil v0.1.1 // indirect
 	github.com/hashicorp/mdns v1.0.1 // indirect
 	github.com/hashicorp/vic v1.5.1-0.20190403131502-bbfe86ec9443 // indirect
+	github.com/huandu/xstrings v1.3.2 // indirect
+	github.com/imdario/mergo v0.3.12 // indirect
 	github.com/ishidawataru/sctp v0.0.0-20191218070446-00ab2ac2db07 // indirect
+	github.com/jefferai/isbadcipher v0.0.0-20190226160619-51d2077c035f // indirect
 	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/joyent/triton-go v0.0.0-20190112182421-51ffac552869 // indirect
 	github.com/klauspost/compress v1.13.6 // indirect

go.sum

@@ -103,6 +103,12 @@ github.com/DataDog/datadog-go v3.2.0+incompatible h1:qSG2N4FghB1He/r2mFrWKCaL7dX
 github.com/DataDog/datadog-go v3.2.0+incompatible/go.mod h1:LButxg5PwREeZtORoXG3tL4fMGNddJ+vMq1mwgfaqoQ=
 github.com/LK4D4/joincontext v0.0.0-20171026170139-1724345da6d5 h1:U7q69tqXiCf6m097GRlNQB0/6SI1qWIOHYHhCEvDxF4=
 github.com/LK4D4/joincontext v0.0.0-20171026170139-1724345da6d5/go.mod h1:nxQPcNPR/34g+HcK2hEsF99O+GJgIkW/OmPl8wtzhmk=
+github.com/Masterminds/goutils v1.1.0 h1:zukEsf/1JZwCMgHiK3GZftabmxiCw4apj3a28RPBiVg=
+github.com/Masterminds/goutils v1.1.0/go.mod h1:8cTjp+g8YejhMuvIA5y2vz3BpJxksy863GQaJW2MFNU=
+github.com/Masterminds/semver v1.5.0 h1:H65muMkzWKEuNDnfl9d70GUjFniHKHRbFPGBuZ3QEww=
+github.com/Masterminds/semver v1.5.0/go.mod h1:MB6lktGJrhw8PrUyiEoblNEGEQ+RzHPF078ddwwvV3Y=
+github.com/Masterminds/sprig v2.22.0+incompatible h1:z4yfnGrZ7netVz+0EDJ0Wi+5VZCSYp4Z0m2dk6cEM60=
+github.com/Masterminds/sprig v2.22.0+incompatible/go.mod h1:y6hNFY5UBTIWBxnzTeuNhlNS5hqE0NB0E6fgfo2Br3o=
 github.com/Microsoft/hcsshim v0.8.6/go.mod h1:Op3hHsoHPAvb6lceZHDtd9OkTew38wNoXnJs8iY7rUg=
 github.com/Microsoft/hcsshim v0.8.7-0.20190325164909-8abdbb8205e4/go.mod h1:Op3hHsoHPAvb6lceZHDtd9OkTew38wNoXnJs8iY7rUg=
 github.com/Microsoft/hcsshim v0.8.7/go.mod h1:OHd7sQqRFrYd3RmSgbgji+ctCwkbq2wbEYNSzOYtcBQ=
@@ -729,6 +735,16 @@ github.com/hashicorp/go-rootcerts v1.0.2 h1:jzhAVGtqPKbwpyCPELlgNWhE1znq+qwJtW5O
 github.com/hashicorp/go-rootcerts v1.0.2/go.mod h1:pqUvnprVnM5bf7AOirdbb01K4ccR319Vf4pU3K5EGc8=
 github.com/hashicorp/go-safetemp v1.0.0 h1:2HR189eFNrjHQyENnQMMpCiBAsRxzbTMIgBhEyExpmo=
 github.com/hashicorp/go-safetemp v1.0.0/go.mod h1:oaerMy3BhqiTbVye6QuFhFtIceqFoDHxNAB65b+Rj1I=
+github.com/hashicorp/go-secure-stdlib/listenerutil v0.1.4 h1:6ajbq64FhrIJZ6prrff3upVVDil4yfCrnSKwTH0HIPE=
+github.com/hashicorp/go-secure-stdlib/listenerutil v0.1.4/go.mod h1:myX7XYMJRIP4PLHtYJiKMTJcKOX0M5ZJNwP0iw+l3uw=
+github.com/hashicorp/go-secure-stdlib/parseutil v0.1.1 h1:78ki3QBevHwYrVxnyVeaEz+7WtifHhauYF23es/0KlI=
+github.com/hashicorp/go-secure-stdlib/parseutil v0.1.1/go.mod h1:QmrqtbKuxxSWTN3ETMPuB+VtEiBJ/A9XhoYGv8E1uD8=
+github.com/hashicorp/go-secure-stdlib/reloadutil v0.1.1 h1:SMGUnbpAcat8rIKHkBPjfv81yC46a8eCNZ2hsR2l1EI=
+github.com/hashicorp/go-secure-stdlib/reloadutil v0.1.1/go.mod h1:Ch/bf00Qnx77MZd49JRgHYqHQjtEmTgGU2faufpVZb0=
+github.com/hashicorp/go-secure-stdlib/strutil v0.1.1 h1:nd0HIW15E6FG1MsnArYaHfuw9C2zgzM8LxkG5Ty/788=
+github.com/hashicorp/go-secure-stdlib/strutil v0.1.1/go.mod h1:gKOamz3EwoIoJq7mlMIRBpVTAUn8qPCrEclOKKWhD3U=
+github.com/hashicorp/go-secure-stdlib/tlsutil v0.1.1 h1:Yc026VyMyIpq1UWRnakHRG01U8fJm+nEfEmjoAb00n8=
+github.com/hashicorp/go-secure-stdlib/tlsutil v0.1.1/go.mod h1:l8slYwnJA26yBz+ErHpp2IRCLr0vuOMGBORIz4rRiAs=
 github.com/hashicorp/go-sockaddr v1.0.0/go.mod h1:7Xibr9yA9JjQq1JpNB2Vw7kxv8xerXegt+ozgdvDeDU=
 github.com/hashicorp/go-sockaddr v1.0.2 h1:ztczhD1jLxIRjVejw8gFomI1BQZOe2WoVOu0SyteCQc=
 github.com/hashicorp/go-sockaddr v1.0.2/go.mod h1:rB4wwRAUzs07qva3c5SdrY/NEtAUjGlgmH/UkBUC97A=
@@ -799,6 +815,8 @@ github.com/hexdigest/gowrap v1.1.7/go.mod h1:Z+nBFUDLa01iaNM+/jzoOA1JJ7sm51rnYFa
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/hpcloud/tail v1.0.1-0.20170814160653-37f427138745 h1:8as8OQ+RF1QrsHvWWsKBtBKINhD9QaD1iozA1wrO4aA=
 github.com/hpcloud/tail v1.0.1-0.20170814160653-37f427138745/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
+github.com/huandu/xstrings v1.3.2 h1:L18LIDzqlW6xN2rEkpdV8+oL/IXWJ1APd+vsdYy4Wdw=
+github.com/huandu/xstrings v1.3.2/go.mod h1:y5/lhBue+AyNmUVz9RLU9xbLR0o4KIIExikq4ovT0aE=
 github.com/iancoleman/strcase v0.2.0/go.mod h1:iwCmte+B7n89clKwxIoIXy/HfoL7AsD47ZCWhYzw7ho=
 github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
 github.com/ianlancetaylor/demangle v0.0.0-20200824232613-28f6c0f3b639/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
@@ -807,6 +825,7 @@ github.com/imdario/mergo v0.3.6/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJ
 github.com/imdario/mergo v0.3.8/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJh5FfA=
 github.com/imdario/mergo v0.3.10/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/imdario/mergo v0.3.11/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
+github.com/imdario/mergo v0.3.12 h1:b6R2BslTbIEToALKP7LxUvijTsNI9TAe80pLWN2g/HU=
 github.com/imdario/mergo v0.3.12/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
 github.com/ishidawataru/sctp v0.0.0-20191218070446-00ab2ac2db07 h1:rw3IAne6CDuVFlZbPOkA7bhxlqawFh7RJJ+CejfMaxE=
@@ -815,6 +834,8 @@ github.com/j-keck/arping v0.0.0-20160618110441-2cf9dc699c56/go.mod h1:ymszkNOg6t
 github.com/j-keck/arping v1.0.2/go.mod h1:aJbELhR92bSk7tp79AWM/ftfc90EfEi2bQJrbBFOsPw=
 github.com/jarcoal/httpmock v0.0.0-20180424175123-9c70cfe4a1da h1:FjHUJJ7oBW4G/9j1KzlHaXL09LyMVM9rupS39lncbXk=
 github.com/jarcoal/httpmock v0.0.0-20180424175123-9c70cfe4a1da/go.mod h1:ks+b9deReOc7jgqp+e7LuFiCBH6Rm5hL32cLcEAArb4=
+github.com/jefferai/isbadcipher v0.0.0-20190226160619-51d2077c035f h1:E87tDTVS5W65euzixn7clSzK66puSt1H4I5SC0EmHH4=
+github.com/jefferai/isbadcipher v0.0.0-20190226160619-51d2077c035f/go.mod h1:3J2qVK16Lq8V+wfiL2lPeDZ7UWMxk5LemerHa1p6N00=
 github.com/jhump/protoreflect v1.6.0 h1:h5jfMVslIg6l29nsMs0D8Wj17RDVdNYti0vDN/PZZoE=
 github.com/jhump/protoreflect v1.6.0/go.mod h1:eaTn3RZAmMBcV0fifFvlm6VHNz3wSkYyXYWUh7ymB74=
 github.com/jmespath/go-jmespath v0.0.0-20160202185014-0b12d6b521d8/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
@@ -911,8 +932,9 @@ github.com/miekg/dns v1.1.26/go.mod h1:bPDLeHnStXmXAq1m/Ch/hvfNHr14JKNPMBo3VZKju
 github.com/miekg/pkcs11 v1.0.3/go.mod h1:XsNlhZGX73bx86s2hdc/FuaLm2CPZJemRLMA+WTFxgs=
 github.com/mistifyio/go-zfs v2.1.2-0.20190413222219-f784269be439+incompatible/go.mod h1:8AuVvqP/mXw1px98n46wfvcGfQ4ci2FwoAjKYxuo3Z4=
 github.com/mitchellh/cli v1.0.0/go.mod h1:hNIlj7HEI86fIcpObd7a0FcrxTWetlwJDGcceTlRvqc=
-github.com/mitchellh/cli v1.1.0 h1:tEElEatulEHDeedTxwckzyYMA5c86fbmNIUL1hBIiTg=
 github.com/mitchellh/cli v1.1.0/go.mod h1:xcISNoH86gajksDmfB23e/pu+B+GeFRMYmoHXxx3xhI=
+github.com/mitchellh/cli v1.1.2 h1:PvH+lL2B7IQ101xQL63Of8yFS2y+aDlsFcsqNc+u/Kw=
+github.com/mitchellh/cli v1.1.2/go.mod h1:6iaV0fGdElS6dPBx0EApTxHrcWvmJphyh2n8YBLPPZ4=
 github.com/mitchellh/colorstring v0.0.0-20150917214807-8631ce90f286 h1:KHyL+3mQOF9sPfs26lsefckcFNDcIZtiACQiECzIUkw=
 github.com/mitchellh/colorstring v0.0.0-20150917214807-8631ce90f286/go.mod h1:l0dey0ia/Uv7NcFFVbCLtqEBQbrT4OCwCSKTEv6enCw=
 github.com/mitchellh/copystructure v1.0.0/go.mod h1:SNtv71yrdKgLRyLFxmLdkAbkKEFWgYaq1OVrnRcwhnw=

nomad/structs/config/consul.go

 package config
 
 import (
+	"fmt"
 	"net/http"
 	"strings"
 	"time"
 
 	consul "github.com/hashicorp/consul/api"
+	"github.com/hashicorp/go-secure-stdlib/listenerutil"
 	"github.com/hashicorp/nomad/helper"
 )
 
@@ -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 := listenerutil.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 +169,40 @@ func TestConsulConfig_Exec(t *testing.T) {
 	require.NotNil(t, conf.VerifySSL)
 	assert.True(t, *conf.VerifySSL)
 }
+
+func TestConsulConfig_IpTemplateParse(t *testing.T) {
+	t.Parallel()
+
+	privateIps, err := sockaddr.GetPrivateIP()
+	require.NoError(t, err)
+	privateIp := strings.Split(privateIps, " ")[0]
+
+	testCases := []struct {
+		name        string
+		tmpl        string
+		expectedOut string
+		expectErr   bool
+	} {
+		{ name: "string address keeps working", tmpl: "10.0.1.0:8500", 					  expectedOut: "10.0.1.0:8500", 	expectErr: false },
+		{ name: "single ip sock-addr template", tmpl: "{{ GetPrivateIP }}:8500",  expectedOut: privateIp+":8500", expectErr: false },
+		{ name: "multi ip sock-addr template", 	tmpl: "{{ GetPrivateIPs }}:8500", expectedOut: "", 								expectErr: true },
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			conf := ConsulConfig{
+				Addr: tc.tmpl,
+			}
+			out, err := conf.ApiConfig()
+
+			if tc.expectErr {
+				require.Error(t, err)
+				return
+			}
+			require.NoError(t, err)
+			require.Equal(t, tc.expectedOut, out.Address)
+		})
+	}
+}

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://pkg.go.dev/github.com/hashicorp/go-sockaddr/template