provider/aws: Add Support for maintenance_window and back_window to rds_cluster_instance (#13134)

* provider/aws: Add Support for maintenance_window and back_window to rds_cluster_instance

Fixes: #9489

```
% make testacc TEST=./builtin/providers/aws TESTARGS='-run=TestAccAWSRDSClusterInstance_basic'
==> Checking that code complies with gofmt requirements...
go generate $(go list ./... | grep -v /terraform/vendor/)
2017/03/28 23:08:45 Generated command/internal_plugin_list.go
TF_ACC=1 go test ./builtin/providers/aws -v -run=TestAccAWSRDSClusterInstance_basic -timeout 120m
=== RUN   TestAccAWSRDSClusterInstance_basic
--- PASS: TestAccAWSRDSClusterInstance_basic (1433.41s)
PASS
ok  	github.com/hashicorp/terraform/builtin/providers/aws	1433.438s
```

* Update rds_cluster_instance.html.markdown

* Update rds_cluster_instance.html.markdown

builtin/providers/aws/resource_aws_rds_cluster_instance.go

@@ -3,6 +3,7 @@ package aws
 import (
 	"fmt"
 	"log"
+	"strings"
 	"time"
 
 	"github.com/aws/aws-sdk-go/aws"
@@ -105,6 +106,27 @@ func resourceAwsRDSClusterInstance() *schema.Resource {
 				Computed: true,
 			},
 
+			"preferred_maintenance_window": {
+				Type:     schema.TypeString,
+				Optional: true,
+				Computed: true,
+				StateFunc: func(v interface{}) string {
+					if v != nil {
+						value := v.(string)
+						return strings.ToLower(value)
+					}
+					return ""
+				},
+				ValidateFunc: validateOnceAWeekWindowFormat,
+			},
+
+			"preferred_backup_window": {
+				Type:         schema.TypeString,
+				Optional:     true,
+				Computed:     true,
+				ValidateFunc: validateOnceADayWindowFormat,
+			},
+
 			"monitoring_interval": {
 				Type:     schema.TypeInt,
 				Optional: true,
@@ -154,6 +176,14 @@ func resourceAwsRDSClusterInstanceCreate(d *schema.ResourceData, meta interface{
 		createOpts.MonitoringRoleArn = aws.String(attr.(string))
 	}
 
+	if attr, ok := d.GetOk("preferred_backup_window"); ok {
+		createOpts.PreferredBackupWindow = aws.String(attr.(string))
+	}
+
+	if attr, ok := d.GetOk("preferred_maintenance_window"); ok {
+		createOpts.PreferredMaintenanceWindow = aws.String(attr.(string))
+	}
+
 	if attr, ok := d.GetOk("monitoring_interval"); ok {
 		createOpts.MonitoringInterval = aws.Int64(int64(attr.(int)))
 	}
@@ -239,6 +269,8 @@ func resourceAwsRDSClusterInstanceRead(d *schema.ResourceData, meta interface{})
 	d.Set("kms_key_id", db.KmsKeyId)
 	d.Set("auto_minor_version_upgrade", db.AutoMinorVersionUpgrade)
 	d.Set("promotion_tier", db.PromotionTier)
+	d.Set("preferred_backup_window", db.PreferredBackupWindow)
+	d.Set("preferred_maintenance_window", db.PreferredMaintenanceWindow)
 
 	if db.MonitoringInterval != nil {
 		d.Set("monitoring_interval", db.MonitoringInterval)
@@ -290,6 +322,18 @@ func resourceAwsRDSClusterInstanceUpdate(d *schema.ResourceData, meta interface{
 		requestUpdate = true
 	}
 
+	if d.HasChange("preferred_backup_window") {
+		d.SetPartial("preferred_backup_window")
+		req.PreferredBackupWindow = aws.String(d.Get("preferred_backup_window").(string))
+		requestUpdate = true
+	}
+
+	if d.HasChange("preferred_maintenance_window") {
+		d.SetPartial("preferred_maintenance_window")
+		req.PreferredMaintenanceWindow = aws.String(d.Get("preferred_maintenance_window").(string))
+		requestUpdate = true
+	}
+
 	if d.HasChange("monitoring_interval") {
 		d.SetPartial("monitoring_interval")
 		req.MonitoringInterval = aws.Int64(int64(d.Get("monitoring_interval").(int)))

builtin/providers/aws/resource_aws_rds_cluster_instance_test.go

@@ -30,6 +30,8 @@ func TestAccAWSRDSClusterInstance_basic(t *testing.T) {
 					testAccCheckAWSClusterInstanceExists("aws_rds_cluster_instance.cluster_instances", &v),
 					testAccCheckAWSDBClusterInstanceAttributes(&v),
 					resource.TestCheckResourceAttr("aws_rds_cluster_instance.cluster_instances", "auto_minor_version_upgrade", "true"),
+					resource.TestCheckResourceAttrSet("aws_rds_cluster_instance.cluster_instances", "preferred_maintenance_window"),
+					resource.TestCheckResourceAttrSet("aws_rds_cluster_instance.cluster_instances", "preferred_backup_window"),
 				),
 			},
 			{

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

@@ -70,7 +70,11 @@ details on controlling this property.
 enhanced monitoring metrics to CloudWatch Logs. You can find more information on the [AWS Documentation](http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Monitoring.html)
 what IAM permissions are needed to allow Enhanced Monitoring for RDS Instances.
 * `monitoring_interval` - (Optional) The interval, in seconds, between points when Enhanced Monitoring metrics are collected for the DB instance. To disable collecting Enhanced Monitoring metrics, specify 0. The default is 0. Valid Values: 0, 1, 5, 10, 15, 30, 60.
-* `promotion_tier` - (Optional) Default 0. Failover Priority setting on instance level. The reader who has lower tier has higher priority to get promoter to writer
+* `promotion_tier` - (Optional) Default 0. Failover Priority setting on instance level. The reader who has lower tier has higher priority to get promoter to writer. 
+* `preferred_backup_window` - (Optional) The daily time range during which automated backups are created if automated backups are enabled.
+  Eg: "04:00-09:00"
+* `preferred_maintenance_window` - (Optional) The window to perform maintenance in.
+  Syntax: "ddd:hh24:mi-ddd:hh24:mi". Eg: "Mon:00:00-Mon:03:00".
 * `tags` - (Optional) A mapping of tags to assign to the instance.
 
 ## Attributes Reference