provider/aws: Add Support for aws_cloudwatch_metric_alarm extended

statistic

Fixes: #11189

This introduces a new parameter and makes an existing parameter from
`required` to `optional` as both cannot be specified together

```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSCloudWatchMetricAlarm_' 2 ↵ ✹ ✭
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/01/13 11:25:24 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSCloudWatchMetricAlarm_ -timeout 120m
=== RUN   TestAccAWSCloudWatchMetricAlarm_importBasic
--- PASS: TestAccAWSCloudWatchMetricAlarm_importBasic (19.80s)
=== RUN   TestAccAWSCloudWatchMetricAlarm_basic
--- PASS: TestAccAWSCloudWatchMetricAlarm_basic (20.42s)
=== RUN   TestAccAWSCloudWatchMetricAlarm_extendedStatistic
--- PASS: TestAccAWSCloudWatchMetricAlarm_extendedStatistic (18.92s)
PASS
```

builtin/providers/aws/resource_aws_cloudwatch_metric_alarm.go

@@ -21,71 +21,75 @@ func resourceAwsCloudWatchMetricAlarm() *schema.Resource {
 		},
 
 		Schema: map[string]*schema.Schema{
-			"alarm_name": &schema.Schema{
+			"alarm_name": {
 				Type:     schema.TypeString,
 				Required: true,
 				ForceNew: true,
 			},
-			"comparison_operator": &schema.Schema{
+			"comparison_operator": {
 				Type:     schema.TypeString,
 				Required: true,
 			},
-			"evaluation_periods": &schema.Schema{
+			"evaluation_periods": {
 				Type:     schema.TypeInt,
 				Required: true,
 			},
-			"metric_name": &schema.Schema{
+			"metric_name": {
 				Type:     schema.TypeString,
 				Required: true,
 			},
-			"namespace": &schema.Schema{
+			"namespace": {
 				Type:     schema.TypeString,
 				Required: true,
 			},
-			"period": &schema.Schema{
+			"period": {
 				Type:     schema.TypeInt,
 				Required: true,
 			},
-			"statistic": &schema.Schema{
+			"statistic": {
 				Type:     schema.TypeString,
-				Required: true,
+				Optional: true,
 			},
-			"threshold": &schema.Schema{
+			"threshold": {
 				Type:     schema.TypeFloat,
 				Required: true,
 			},
-			"actions_enabled": &schema.Schema{
+			"actions_enabled": {
 				Type:     schema.TypeBool,
 				Optional: true,
 				Default:  true,
 			},
-			"alarm_actions": &schema.Schema{
+			"alarm_actions": {
 				Type:     schema.TypeSet,
 				Optional: true,
 				Elem:     &schema.Schema{Type: schema.TypeString},
 				Set:      schema.HashString,
 			},
-			"alarm_description": &schema.Schema{
+			"alarm_description": {
 				Type:     schema.TypeString,
 				Optional: true,
 			},
-			"dimensions": &schema.Schema{
+			"dimensions": {
 				Type:     schema.TypeMap,
 				Optional: true,
 			},
-			"insufficient_data_actions": &schema.Schema{
+			"insufficient_data_actions": {
 				Type:     schema.TypeSet,
 				Optional: true,
 				Elem:     &schema.Schema{Type: schema.TypeString},
 				Set:      schema.HashString,
 			},
-			"ok_actions": &schema.Schema{
+			"ok_actions": {
 				Type:     schema.TypeSet,
 				Optional: true,
 				Elem:     &schema.Schema{Type: schema.TypeString},
 				Set:      schema.HashString,
 			},
-			"unit": &schema.Schema{
+			"unit": {
+				Type:     schema.TypeString,
+				Optional: true,
+			},
+			"extended_statistic": {
 				Type:     schema.TypeString,
 				Optional: true,
 			},
@@ -147,6 +151,7 @@ func resourceAwsCloudWatchMetricAlarmRead(d *schema.ResourceData, meta interface
 	d.Set("statistic", a.Statistic)
 	d.Set("threshold", a.Threshold)
 	d.Set("unit", a.Unit)
+	d.Set("extended_statistic", a.ExtendedStatistic)
 
 	return nil
 }
@@ -199,7 +204,6 @@ func getAwsCloudWatchPutMetricAlarmInput(d *schema.ResourceData) cloudwatch.PutM
 		MetricName:         aws.String(d.Get("metric_name").(string)),
 		Namespace:          aws.String(d.Get("namespace").(string)),
 		Period:             aws.Int64(int64(d.Get("period").(int))),
-		Statistic:          aws.String(d.Get("statistic").(string)),
 		Threshold:          aws.Float64(d.Get("threshold").(float64)),
 	}
 
@@ -215,6 +219,14 @@ func getAwsCloudWatchPutMetricAlarmInput(d *schema.ResourceData) cloudwatch.PutM
 		params.Unit = aws.String(v.(string))
 	}
 
+	if v, ok := d.GetOk("statistic"); ok {
+		params.Statistic = aws.String(v.(string))
+	}
+
+	if v, ok := d.GetOk("extended_statistic"); ok {
+		params.ExtendedStatistic = aws.String(v.(string))
+	}
+
 	var alarmActions []*string
 	if v := d.Get("alarm_actions"); v != nil {
 		for _, v := range v.(*schema.Set).List() {

builtin/providers/aws/resource_aws_cloudwatch_metric_alarm_test.go

@@ -18,7 +18,7 @@ func TestAccAWSCloudWatchMetricAlarm_basic(t *testing.T) {
 		Providers:    testAccProviders,
 		CheckDestroy: testAccCheckAWSCloudWatchMetricAlarmDestroy,
 		Steps: []resource.TestStep{
-			resource.TestStep{
+			{
 				Config: testAccAWSCloudWatchMetricAlarmConfig,
 				Check: resource.ComposeTestCheckFunc(
 					testAccCheckCloudWatchMetricAlarmExists("aws_cloudwatch_metric_alarm.foobar", &alarm),
@@ -32,6 +32,25 @@ func TestAccAWSCloudWatchMetricAlarm_basic(t *testing.T) {
 	})
 }
 
+func TestAccAWSCloudWatchMetricAlarm_extendedStatistic(t *testing.T) {
+	var alarm cloudwatch.MetricAlarm
+
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckAWSCloudWatchMetricAlarmDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccAWSCloudWatchMetricAlarmConfigExtendedStatistic,
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckCloudWatchMetricAlarmExists("aws_cloudwatch_metric_alarm.foobar", &alarm),
+					resource.TestCheckResourceAttr("aws_cloudwatch_metric_alarm.foobar", "extended_statistic", "p88.0"),
+				),
+			},
+		},
+	})
+}
+
 func testAccCheckCloudWatchMetricAlarmDimension(n, k, v string) resource.TestCheckFunc {
 	return func(s *terraform.State) error {
 		rs, ok := s.RootModule().Resources[n]
@@ -116,3 +135,21 @@ resource "aws_cloudwatch_metric_alarm" "foobar" {
   }
 }
 `)
+
+var testAccAWSCloudWatchMetricAlarmConfigExtendedStatistic = fmt.Sprintf(`
+resource "aws_cloudwatch_metric_alarm" "foobar" {
+  alarm_name                = "terraform-test-foobar6"
+  comparison_operator       = "GreaterThanOrEqualToThreshold"
+  evaluation_periods        = "2"
+  metric_name               = "CPUUtilization"
+  namespace                 = "AWS/EC2"
+  period                    = "120"
+  extended_statistic	    = "p88.0"
+  threshold                 = "80"
+  alarm_description         = "This metric monitors ec2 cpu utilization"
+  insufficient_data_actions = []
+  dimensions {
+    InstanceId = "i-abc123"
+  }
+}
+`)

website/source/docs/providers/aws/r/cloudwatch_metric_alarm.html.markdown

@@ -67,7 +67,7 @@ The following arguments are supported:
 * `namespace` - (Required) The namespace for the alarm's associated metric. See docs for the [list of namespaces](https://docs.aws.amazon.com/AmazonCloudWatch/latest/DeveloperGuide/aws-namespaces.html).
   See docs for [supported metrics](https://docs.aws.amazon.com/AmazonCloudWatch/latest/DeveloperGuide/CW_Support_For_AWS.html).
 * `period` - (Required) The period in seconds over which the specified `statistic` is applied.
-* `statistic` - (Required) The statistic to apply to the alarm's associated metric.
+* `statistic` - (Optional) The statistic to apply to the alarm's associated metric.
    Either of the following is supported: `SampleCount`, `Average`, `Sum`, `Minimum`, `Maximum`
 * `threshold` - (Required) The value against which the specified statistic is compared.
 * `actions_enabled` - (Optional) Indicates whether or not actions should be executed during any changes to the alarm's state. Defaults to `true`.
@@ -77,6 +77,7 @@ The following arguments are supported:
 * `insufficient_data_actions` - (Optional) The list of actions to execute when this alarm transitions into an INSUFFICIENT_DATA state from any other state. Each action is specified as an Amazon Resource Number (ARN).
 * `ok_actions` - (Optional) The list of actions to execute when this alarm transitions into an OK state from any other state. Each action is specified as an Amazon Resource Number (ARN).
 * `unit` - (Optional) The unit for the alarm's associated metric.
+* `extended_statistic` - (Optional) The percentile statistic for the metric associated with the alarm. Specify a value between p0.0 and p100. You cannot create a metric alarm made of both `statistic` and `extended_statistic` parameters.
 
 ## Attributes Reference
 
@@ -85,7 +86,6 @@ The following attributes are exported:
 * `id` - The ID of the health check
 
 
-
 ## Import
 
 Cloud Metric Alarms can be imported using the `alarm_name`, e.g.