Find LB listener by the LB ARN

aws/data_source_aws_lb_listener.go

@@ -1,6 +1,13 @@
 package aws
 
-import "github.com/hashicorp/terraform/helper/schema"
+import (
+	"fmt"
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/elbv2"
+	"github.com/hashicorp/errwrap"
+	"github.com/hashicorp/terraform/helper/schema"
+	"log"
+)
 
 func dataSourceAwsLbListener() *schema.Resource {
 	return &schema.Resource{
@@ -9,11 +16,13 @@ func dataSourceAwsLbListener() *schema.Resource {
 		Schema: map[string]*schema.Schema{
 			"arn": {
 				Type:     schema.TypeString,
-				Required: true,
+				Optional: true,
+				Computed: true,
 			},
 
 			"load_balancer_arn": {
 				Type:     schema.TypeString,
+				Optional: true,
 				Computed: true,
 			},
 			"port": {
@@ -57,6 +66,35 @@ func dataSourceAwsLbListener() *schema.Resource {
 }
 
 func dataSourceAwsLbListenerRead(d *schema.ResourceData, meta interface{}) error {
-	d.SetId(d.Get("arn").(string))
+	listenerArn := d.Get("arn").(string)
+	lbArn := d.Get("load_balancer_arn").(string)
+
+	switch {
+	case listenerArn != "":
+		d.SetId(d.Get("arn").(string))
+	case lbArn != "":
+		elbconn := meta.(*AWSClient).elbv2conn
+
+		resp, err := elbconn.DescribeListeners(&elbv2.DescribeListenersInput{
+			LoadBalancerArn: aws.String(lbArn),
+		})
+
+		if err != nil {
+			if isListenerNotFound(err) {
+				log.Printf("[WARN] DescribeListeners - removing %s from state", d.Id())
+				d.SetId("")
+				return nil
+			}
+			return errwrap.Wrapf("Error retrieving Listener: {{err}}", err)
+		}
+
+		if len(resp.Listeners) != 1 {
+			return fmt.Errorf("Multiple listeners found for load balancer %s. This data source only supports single listener load balancers when searching by load balancer.", lbArn)
+		}
+
+		d.SetId(*resp.Listeners[0].ListenerArn)
+	}
+
 	return resourceAwsLbListenerRead(d, meta)
+
 }

aws/data_source_aws_lb_listener_test.go

@@ -34,6 +34,30 @@ func TestAccDataSourceAWSLBListener_basic(t *testing.T) {
 	})
 }
 
+func TestAccDataSourceAWSLBListenerByLBArn(t *testing.T) {
+	lbName := fmt.Sprintf("testlistener-lbarn-%s", acctest.RandStringFromCharSet(13, acctest.CharSetAlphaNum))
+	targetGroupName := fmt.Sprintf("testtargetgroup-%s", acctest.RandStringFromCharSet(10, acctest.CharSetAlphaNum))
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:  func() { testAccPreCheck(t) },
+		Providers: testAccProviders,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccDataSourceAWSLBListenerConfigByLBArn(lbName, targetGroupName),
+				Check: resource.ComposeAggregateTestCheckFunc(
+					resource.TestCheckResourceAttrSet("data.aws_lb_listener.front_end", "load_balancer_arn"),
+					resource.TestCheckResourceAttrSet("data.aws_lb_listener.front_end", "arn"),
+					resource.TestCheckResourceAttr("data.aws_lb_listener.front_end", "protocol", "HTTP"),
+					resource.TestCheckResourceAttr("data.aws_lb_listener.front_end", "port", "80"),
+					resource.TestCheckResourceAttr("data.aws_lb_listener.front_end", "default_action.#", "1"),
+					resource.TestCheckResourceAttr("data.aws_lb_listener.front_end", "default_action.0.type", "forward"),
+					resource.TestCheckResourceAttrSet("data.aws_lb_listener.front_end", "default_action.0.target_group_arn"),
+				),
+			},
+		},
+	})
+}
+
 func TestAccDataSourceAWSLBListenerBackwardsCompatibility(t *testing.T) {
 	lbName := fmt.Sprintf("testlistener-basic-%s", acctest.RandStringFromCharSet(13, acctest.CharSetAlphaNum))
 	targetGroupName := fmt.Sprintf("testtargetgroup-%s", acctest.RandStringFromCharSet(10, acctest.CharSetAlphaNum))
@@ -184,6 +208,106 @@ data "aws_lb_listener" "front_end" {
 }`, lbName, targetGroupName)
 }
 
+func testAccDataSourceAWSLBListenerConfigByLBArn(lbName, targetGroupName string) string {
+	return fmt.Sprintf(`resource "aws_lb_listener" "front_end" {
+   load_balancer_arn = "${aws_lb.alb_test.id}"
+   protocol = "HTTP"
+   port = "80"
+
+   default_action {
+     target_group_arn = "${aws_lb_target_group.test.id}"
+     type = "forward"
+   }
+}
+
+resource "aws_lb" "alb_test" {
+  name            = "%s"
+  internal        = true
+  security_groups = ["${aws_security_group.alb_test.id}"]
+  subnets         = ["${aws_subnet.alb_test.*.id}"]
+
+  idle_timeout = 30
+  enable_deletion_protection = false
+
+  tags {
+    TestName = "TestAccAWSALB_basic"
+  }
+}
+
+resource "aws_lb_target_group" "test" {
+  name = "%s"
+  port = 8080
+  protocol = "HTTP"
+  vpc_id = "${aws_vpc.alb_test.id}"
+
+  health_check {
+    path = "/health"
+    interval = 60
+    port = 8081
+    protocol = "HTTP"
+    timeout = 3
+    healthy_threshold = 3
+    unhealthy_threshold = 3
+    matcher = "200-299"
+  }
+}
+
+variable "subnets" {
+  default = ["10.0.1.0/24", "10.0.2.0/24"]
+  type    = "list"
+}
+
+data "aws_availability_zones" "available" {}
+
+resource "aws_vpc" "alb_test" {
+  cidr_block = "10.0.0.0/16"
+
+  tags {
+    TestName = "TestAccAWSALB_basic"
+  }
+}
+
+resource "aws_subnet" "alb_test" {
+  count                   = 2
+  vpc_id                  = "${aws_vpc.alb_test.id}"
+  cidr_block              = "${element(var.subnets, count.index)}"
+  map_public_ip_on_launch = true
+  availability_zone       = "${element(data.aws_availability_zones.available.names, count.index)}"
+
+  tags {
+    TestName = "TestAccAWSALB_basic"
+  }
+}
+
+resource "aws_security_group" "alb_test" {
+  name        = "allow_all_alb_test"
+  description = "Used for ALB Testing"
+  vpc_id      = "${aws_vpc.alb_test.id}"
+
+  ingress {
+    from_port   = 0
+    to_port     = 0
+    protocol    = "-1"
+    cidr_blocks = ["0.0.0.0/0"]
+  }
+
+  egress {
+    from_port   = 0
+    to_port     = 0
+    protocol    = "-1"
+    cidr_blocks = ["0.0.0.0/0"]
+  }
+
+  tags {
+    TestName = "TestAccAWSALB_basic"
+  }
+}
+
+data "aws_lb_listener" "front_end" {
+	load_balancer_arn = "${aws_lb_listener.front_end.load_balancer_arn}"
+}`, lbName, targetGroupName)
+}
+
 func testAccDataSourceAWSLBListenerConfigBackwardsCompatibility(lbName, targetGroupName string) string {
 	return fmt.Sprintf(`resource "aws_alb_listener" "front_end" {
    load_balancer_arn = "${aws_alb.alb_test.id}"

website/docs/d/lb_listener.html.markdown

@@ -28,11 +28,26 @@ data "aws_lb_listener" "listener" {
 }
 ```
 
+```hcl
+variable "lb_name" {
+  type = "string"
+}
+
+data "aws_lb" "load_balancer" {
+  name = "${var.lb_name}"
+}
+
+data "aws_lb_listener" "listener" {
+  load_balancer_arn = "${data.aws_lb.load_balancer.arn}"
+}
+```
+
 ## Argument Reference
 
 The following arguments are supported:
 
-* `arn` - (Required) The ARN of the listener.
+* `arn` - (Optional) The ARN of the listener.
+* `load_balancer_arn` - (Optional) The ARN of the load balancer.
 
 ## Attributes Reference