App Service Custom Hostname Binding: support for multiple bindings (#…

…1970)

before this change:

```
$ ARM_TEST_APP_SERVICE=tomdevacctest12345 ARM_TEST_DOMAIN=REDACTED ARM_ALT_TEST_DOMAIN=REDACTED acctests azurerm TestAccAzureRMAppServiceCustomHostnameBinding

=== RUN   TestAccAzureRMAppServiceCustomHostnameBinding
=== RUN   TestAccAzureRMAppServiceCustomHostnameBinding/basic
=== RUN   TestAccAzureRMAppServiceCustomHostnameBinding/basic/basic
=== RUN   TestAccAzureRMAppServiceCustomHostnameBinding/basic/import
--- PASS: TestAccAzureRMAppServiceCustomHostnameBinding (299.70s)
    --- PASS: TestAccAzureRMAppServiceCustomHostnameBinding/basic (299.70s)
        --- PASS: TestAccAzureRMAppServiceCustomHostnameBinding/basic/basic (135.97s)
        --- PASS: TestAccAzureRMAppServiceCustomHostnameBinding/basic/import (163.72s)
=== RUN   TestAccAzureRMAppServiceCustomHostnameBinding_multiple
--- FAIL: TestAccAzureRMAppServiceCustomHostnameBinding_multiple (112.01s)
	testing.go:573: Error destroying resource! WARNING: Dangling resources
		may exist. The full state and error is shown below.

		Error: Error applying: 1 error(s) occurred:

		* azurerm_app_service_custom_hostname_binding.test2 (destroy): 1 error(s) occurred:

		* azurerm_app_service_custom_hostname_binding.test2: web.AppsClient#DeleteHostNameBinding: Failure sending request: StatusCode=409 -- Original Error: autorest/azure: Service returned an error. Status=<nil> <nil>
```

after this change:

```
$ ARM_TEST_APP_SERVICE=tomdevacctest12345 ARM_TEST_DOMAIN=REDACTED ARM_ALT_TEST_DOMAIN=REDACTED acctests azurerm TestAccAzureRMAppServiceCustomHostnameBinding_multiple
=== RUN   TestAccAzureRMAppServiceCustomHostnameBinding_multiple
--- PASS: TestAccAzureRMAppServiceCustomHostnameBinding_multiple (157.72s)
PASS
ok  	github.com/terraform-providers/terraform-provider-azurerm/azurerm	158.148s
```

azurerm/import_arm_app_service_hostname_binding_test.go

@@ -13,8 +13,9 @@ func TestAccAzureRMAppServiceCustomHostnameBinding(t *testing.T) {
 	// the app service name being shared (so the tests don't conflict with each other)
 	testCases := map[string]map[string]func(t *testing.T){
 		"basic": {
-			"basic":  testAccAzureRMAppServiceCustomHostnameBinding_basic,
-			"import": testAccAzureRMAppServiceCustomHostnameBinding_import,
+			"basic":    testAccAzureRMAppServiceCustomHostnameBinding_basic,
+			"multiple": testAccAzureRMAppServiceCustomHostnameBinding_multiple,
+			"import":   testAccAzureRMAppServiceCustomHostnameBinding_import,
 		},
 	}
 

azurerm/resource_arm_app_service_custom_hostname_binding.go

@@ -9,6 +9,8 @@ import (
 	"github.com/terraform-providers/terraform-provider-azurerm/azurerm/utils"
 )
 
+var appServiceCustomHostnameBindingResourceName = "azurerm_app_service_custom_hostname_binding"
+
 func resourceArmAppServiceCustomHostnameBinding() *schema.Resource {
 	return &schema.Resource{
 		Create: resourceArmAppServiceCustomHostnameBindingCreate,
@@ -46,6 +48,9 @@ func resourceArmAppServiceCustomHostnameBindingCreate(d *schema.ResourceData, me
 	appServiceName := d.Get("app_service_name").(string)
 	hostname := d.Get("hostname").(string)
 
+	azureRMLockByName(appServiceName, appServiceCustomHostnameBindingResourceName)
+	defer azureRMUnlockByName(appServiceName, appServiceCustomHostnameBindingResourceName)
+
 	properties := web.HostNameBinding{
 		HostNameBindingProperties: &web.HostNameBindingProperties{
 			SiteName: utils.String(appServiceName),
@@ -110,6 +115,9 @@ func resourceArmAppServiceCustomHostnameBindingDelete(d *schema.ResourceData, me
 	appServiceName := id.Path["sites"]
 	hostname := id.Path["hostNameBindings"]
 
+	azureRMLockByName(appServiceName, appServiceCustomHostnameBindingResourceName)
+	defer azureRMUnlockByName(appServiceName, appServiceCustomHostnameBindingResourceName)
+
 	log.Printf("[DEBUG] Deleting App Service Hostname Binding %q (App Service %q / Resource Group %q)", hostname, appServiceName, resGroup)
 
 	ctx := meta.(*ArmClient).StopContext

azurerm/resource_arm_app_service_custom_hostname_binding_test.go

@@ -45,6 +45,45 @@ func testAccAzureRMAppServiceCustomHostnameBinding_basic(t *testing.T) {
 	})
 }
 
+func testAccAzureRMAppServiceCustomHostnameBinding_multiple(t *testing.T) {
+	appServiceEnvVariable := "ARM_TEST_APP_SERVICE"
+	appServiceEnv := os.Getenv(appServiceEnvVariable)
+	if appServiceEnv == "" {
+		t.Skipf("Skipping as %q is not specified", appServiceEnvVariable)
+	}
+
+	domainEnvVariable := "ARM_TEST_DOMAIN"
+	domainEnv := os.Getenv(domainEnvVariable)
+	if domainEnv == "" {
+		t.Skipf("Skipping as %q is not specified", domainEnvVariable)
+	}
+
+	altDomainEnvVariable := "ARM_ALT_TEST_DOMAIN"
+	altDomainEnv := os.Getenv(altDomainEnvVariable)
+	if domainEnv == "" {
+		t.Skipf("Skipping as %q is not specified", domainEnvVariable)
+	}
+
+	resourceName := "azurerm_app_service_custom_hostname_binding.test"
+	ri := acctest.RandInt()
+	location := testLocation()
+	config := testAccAzureRMAppServiceCustomHostnameBinding_multipleConfig(ri, location, appServiceEnv, domainEnv, altDomainEnv)
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testCheckAzureRMAppServiceCustomHostnameBindingDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: config,
+				Check: resource.ComposeTestCheckFunc(
+					testCheckAzureRMAppServiceCustomHostnameBindingExists(resourceName),
+				),
+			},
+		},
+	})
+}
+
 func testCheckAzureRMAppServiceCustomHostnameBindingDestroy(s *terraform.State) error {
 	client := testAccProvider.Meta().(*ArmClient).appServicesClient
 
@@ -132,3 +171,16 @@ resource "azurerm_app_service_custom_hostname_binding" "test" {
 }
 `, rInt, location, rInt, appServiceName, domain)
 }
+
+func testAccAzureRMAppServiceCustomHostnameBinding_multipleConfig(rInt int, location, appServiceName, domain, altDomain string) string {
+	template := testAccAzureRMAppServiceCustomHostnameBinding_basicConfig(rInt, location, appServiceName, domain)
+	return fmt.Sprintf(`
+%s
+
+resource "azurerm_app_service_custom_hostname_binding" "test2" {
+  hostname            = "%s"
+  app_service_name    = "${azurerm_app_service.test.name}"
+  resource_group_name = "${azurerm_resource_group.test.name}"
+}
+`, template, altDomain)
+}