Feature: Add 'ip_version' to Public IP Address (#2019)

* Feature: Add 'ip_version' to Public IP Address

* Public IP Data Source Info for 'ip_version'

* Public IP Documentation

Update to include 'ip_version' for data and resource documentation.

* Making the IP Version field case sensitive

* Fixing the broken tests

* Adding back in the Zones test

```
$ acctests azurerm TestAccAzureRMPublicIpStatic_zones
=== RUN   TestAccAzureRMPublicIpStatic_zones
--- PASS: TestAccAzureRMPublicIpStatic_zones (111.60s)
PASS
ok  	github.com/terraform-providers/terraform-provider-azurerm/azurerm	113.048s
```

azurerm/data_source_public_ip.go

@@ -20,6 +20,11 @@ func dataSourceArmPublicIP() *schema.Resource {
 
 			"resource_group_name": resourceGroupNameForDataSourceSchema(),
 
+			"ip_version": {
+				Type:     schema.TypeString,
+				Computed: true,
+			},
+
 			"domain_name_label": {
 				Type:     schema.TypeString,
 				Computed: true,
@@ -73,6 +78,10 @@ func dataSourceArmPublicIPRead(d *schema.ResourceData, meta interface{}) error {
 			}
 		}
 
+		if ipVersion := props.PublicIPAddressVersion; string(ipVersion) != "" {
+			d.Set("ip_version", string(ipVersion))
+		}
+
 		if v := props.IPAddress; v != nil && *v != "" {
 			d.Set("ip_address", v)
 		}

azurerm/data_source_public_ip_test.go

@@ -31,6 +31,7 @@ func TestAccDataSourceAzureRMPublicIP_basic(t *testing.T) {
 					resource.TestCheckResourceAttr(dataSourceName, "idle_timeout_in_minutes", "30"),
 					resource.TestCheckResourceAttrSet(dataSourceName, "fqdn"),
 					resource.TestCheckResourceAttrSet(dataSourceName, "ip_address"),
+					resource.TestCheckResourceAttr(dataSourceName, "ip_version", "IPv4"),
 					resource.TestCheckResourceAttr(dataSourceName, "tags.%", "1"),
 					resource.TestCheckResourceAttr(dataSourceName, "tags.environment", "test"),
 				),

azurerm/helpers/validate/network.go

@@ -5,6 +5,30 @@ import (
 	"net"
 )
 
+func IPv6Address(i interface{}, k string) (_ []string, errors []error) {
+	return validateIpv6Address(i, k, false)
+}
+
+func validateIpv6Address(i interface{}, k string, allowEmpty bool) (_ []string, errors []error) {
+	v, ok := i.(string)
+	if !ok {
+		errors = append(errors, fmt.Errorf("expected type of %q to be string", k))
+		return
+	}
+
+	if v == "" && allowEmpty {
+		return
+	}
+
+	ip := net.ParseIP(v)
+	if six := ip.To16(); six == nil {
+		errors = append(errors, fmt.Errorf("%q is not a valid IPv6 address: %q", k, v))
+	}
+
+	return
+
+}
+
 func IPv4Address(i interface{}, k string) (_ []string, errors []error) {
 	return validateIpv4Address(i, k, false)
 }
@@ -26,7 +50,7 @@ func validateIpv4Address(i interface{}, k string, allowEmpty bool) (_ []string,
 
 	ip := net.ParseIP(v)
 	if four := ip.To4(); four == nil {
-		errors = append(errors, fmt.Errorf("%q is not a valid IP4 address: %q", k, v))
+		errors = append(errors, fmt.Errorf("%q is not a valid IPv4 address: %q", k, v))
 	}
 
 	return

azurerm/helpers/validate/network_test.go

@@ -5,6 +5,57 @@ import (
 	"testing"
 )
 
+func TestIPv6Address(t *testing.T) {
+	cases := []struct {
+		IP     string
+		Errors int
+	}{
+		{
+			IP:     "",
+			Errors: 1,
+		},
+		{
+			IP:     "0.0.0.0",
+			Errors: 0,
+		},
+		{
+			IP:     "not:a:real:address:1:2:3:4",
+			Errors: 1,
+		},
+		{
+			IP:     "text",
+			Errors: 1,
+		},
+		{
+			IP:     "::",
+			Errors: 0,
+		},
+		{
+			IP:     "0:0:0:0:0:0:0:0",
+			Errors: 0,
+		},
+		{
+			IP:     "2001:0db8:85a3:0:0:8a2e:0370:7334",
+			Errors: 0,
+		},
+		{
+			IP:     "2001:0db8:85a3:0000:0000:8a2e:0370:7334",
+			Errors: 0,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.IP, func(t *testing.T) {
+			_, errors := IPv6Address(tc.IP, "test")
+
+			if len(errors) != tc.Errors {
+				t.Fatalf("Expected IPv6Address to return %d error(s) not %d", tc.Errors, len(errors))
+			}
+		})
+	}
+
+}
+
 func TestIPv4Address(t *testing.T) {
 	cases := []struct {
 		IP     string

azurerm/resource_arm_public_ip.go

@@ -2,11 +2,12 @@ package azurerm
 
 import (
 	"fmt"
-	"github.com/terraform-providers/terraform-provider-azurerm/azurerm/helpers/suppress"
 	"log"
 	"regexp"
 	"strings"
 
+	"github.com/terraform-providers/terraform-provider-azurerm/azurerm/helpers/suppress"
+
 	"github.com/Azure/azure-sdk-for-go/services/network/mgmt/2018-04-01/network"
 	"github.com/hashicorp/terraform/helper/schema"
 	"github.com/hashicorp/terraform/helper/validation"
@@ -60,6 +61,18 @@ func resourceArmPublicIp() *schema.Resource {
 				}, true),
 			},
 
+			"ip_version": {
+				Type:             schema.TypeString,
+				Optional:         true,
+				Default:          string(network.IPv4),
+				ForceNew:         true,
+				DiffSuppressFunc: suppress.CaseDifference,
+				ValidateFunc: validation.StringInSlice([]string{
+					string(network.IPv4),
+					string(network.IPv6),
+				}, true),
+			},
+
 			"sku": {
 				Type:             schema.TypeString,
 				Optional:         true,
@@ -122,6 +135,13 @@ func resourceArmPublicIpCreate(d *schema.ResourceData, meta interface{}) error {
 
 	idleTimeout := d.Get("idle_timeout_in_minutes").(int)
 	ipAllocationMethod := network.IPAllocationMethod(d.Get("public_ip_address_allocation").(string))
+	ipVersion := network.IPVersion(d.Get("ip_version").(string))
+
+	if strings.EqualFold(string(ipVersion), string(network.IPv6)) {
+		if strings.EqualFold(string(ipAllocationMethod), "static") {
+			return fmt.Errorf("Cannot specify publicIpAllocationMethod as Static for IPv6 PublicIp")
+		}
+	}
 
 	if strings.ToLower(string(sku.Name)) == "standard" {
 		if strings.ToLower(string(ipAllocationMethod)) != "static" {
@@ -135,6 +155,7 @@ func resourceArmPublicIpCreate(d *schema.ResourceData, meta interface{}) error {
 		Sku:      &sku,
 		PublicIPAddressPropertiesFormat: &network.PublicIPAddressPropertiesFormat{
 			PublicIPAllocationMethod: ipAllocationMethod,
+			PublicIPAddressVersion:   ipVersion,
 			IdleTimeoutInMinutes:     utils.Int32(int32(idleTimeout)),
 		},
 		Tags:  expandTags(tags),
@@ -218,6 +239,7 @@ func resourceArmPublicIpRead(d *schema.ResourceData, meta interface{}) error {
 
 	if props := resp.PublicIPAddressPropertiesFormat; props != nil {
 		d.Set("public_ip_address_allocation", strings.ToLower(string(props.PublicIPAllocationMethod)))
+		d.Set("ip_version", strings.ToLower(string(props.PublicIPAddressVersion)))
 
 		if settings := props.DNSSettings; settings != nil {
 			d.Set("fqdn", settings.Fqdn)