emr_cluster/instance: force emr connection argument for refresh func

aws/resource_aws_emr_cluster.go

@@ -360,7 +360,7 @@ func resourceAwsEMRClusterRead(d *schema.ResourceData, meta interface{}) error {
 		d.Set("cluster_state", cluster.Status.State)
 	}
 
-	instanceGroups, err := fetchAllEMRInstanceGroups(meta, d.Id())
+	instanceGroups, err := fetchAllEMRInstanceGroups(emrconn, d.Id())
 	if err == nil {
 		coreGroup := findGroup(instanceGroups, "CORE")
 		if coreGroup != nil {
@@ -414,7 +414,7 @@ func resourceAwsEMRClusterUpdate(d *schema.ResourceData, meta interface{}) error
 	if d.HasChange("core_instance_count") {
 		d.SetPartial("core_instance_count")
 		log.Printf("[DEBUG] Modify EMR cluster")
-		groups, err := fetchAllEMRInstanceGroups(meta, d.Id())
+		groups, err := fetchAllEMRInstanceGroups(conn, d.Id())
 		if err != nil {
 			log.Printf("[DEBUG] Error finding all instance groups: %s", err)
 			return err

aws/resource_aws_emr_instance_group.go

@@ -155,7 +155,8 @@ func resourceAwsEMRInstanceGroupCreate(d *schema.ResourceData, meta interface{})
 }
 
 func resourceAwsEMRInstanceGroupRead(d *schema.ResourceData, meta interface{}) error {
-	group, err := fetchEMRInstanceGroup(meta, d.Get("cluster_id").(string), d.Id())
+	conn := meta.(*AWSClient).emrconn
+	group, err := fetchEMRInstanceGroup(conn, d.Get("cluster_id").(string), d.Id())
 	if err != nil {
 		switch err {
 		case emrInstanceGroupNotFound:
@@ -186,8 +187,7 @@ func resourceAwsEMRInstanceGroupRead(d *schema.ResourceData, meta interface{}) e
 	return nil
 }
 
-func fetchAllEMRInstanceGroups(meta interface{}, clusterId string) ([]*emr.InstanceGroup, error) {
-	conn := meta.(*AWSClient).emrconn
+func fetchAllEMRInstanceGroups(conn *emr.EMR, clusterId string) ([]*emr.InstanceGroup, error) {
 	req := &emr.ListInstanceGroupsInput{
 		ClusterId: aws.String(clusterId),
 	}
@@ -221,8 +221,8 @@ func fetchAllEMRInstanceGroups(meta interface{}, clusterId string) ([]*emr.Insta
 	return groups, nil
 }
 
-func fetchEMRInstanceGroup(meta interface{}, clusterId, groupId string) (*emr.InstanceGroup, error) {
-	groups, err := fetchAllEMRInstanceGroups(meta, clusterId)
+func fetchEMRInstanceGroup(conn *emr.EMR, clusterId, groupId string) (*emr.InstanceGroup, error) {
+	groups, err := fetchAllEMRInstanceGroups(conn, clusterId)
 	if err != nil {
 		return nil, err
 	}
@@ -280,9 +280,9 @@ func resourceAwsEMRInstanceGroupUpdate(d *schema.ResourceData, meta interface{})
 	return resourceAwsEMRInstanceGroupRead(d, meta)
 }
 
-func instanceGroupStateRefresh(meta interface{}, clusterID, igID string) resource.StateRefreshFunc {
+func instanceGroupStateRefresh(conn *emr.EMR, clusterID, igID string) resource.StateRefreshFunc {
 	return func() (interface{}, string, error) {
-		group, err := fetchEMRInstanceGroup(meta, clusterID, igID)
+		group, err := fetchEMRInstanceGroup(conn, clusterID, igID)
 		if err != nil {
 			return nil, "Not Found", err
 		}

aws/resource_aws_emr_instance_group_test.go

@@ -29,6 +29,27 @@ func TestAccAWSEMRInstanceGroup_basic(t *testing.T) {
 	})
 }
 
+// Confirm we can scale down the instance count. Regression test for https://github.com/terraform-providers/terraform-provider-aws/issues/1264
+func TestAccAWSEMRInstanceGroup_zero_count(t *testing.T) {
+	var ig emr.InstanceGroup
+	rInt := acctest.RandInt()
+	resource.Test(t, resource.TestCase{
+		PreCheck:     func() { testAccPreCheck(t) },
+		Providers:    testAccProviders,
+		CheckDestroy: testAccCheckAWSEmrInstanceGroupDestroy,
+		Steps: []resource.TestStep{
+			{
+				Config: testAccAWSEmrInstanceGroupConfig(rInt),
+				Check:  testAccCheckAWSEmrInstanceGroupExists("aws_emr_instance_group.task", &ig),
+			},
+			{
+				Config: testAccAWSEmrInstanceGroupConfig_zero_count(rInt),
+				Check:  testAccCheckAWSEmrInstanceGroupExists("aws_emr_instance_group.task", &ig),
+			},
+		},
+	})
+}
+
 func TestAccAWSEMRInstanceGroup_ebsBasic(t *testing.T) {
 	var ig emr.InstanceGroup
 	rInt := acctest.RandInt()
@@ -93,7 +114,8 @@ func testAccCheckAWSEmrInstanceGroupExists(n string, v *emr.InstanceGroup) resou
 			return fmt.Errorf("No task group id set")
 		}
 		meta := testAccProvider.Meta()
-		g, err := fetchEMRInstanceGroup(meta, rs.Primary.Attributes["cluster_id"], rs.Primary.ID)
+		conn := meta.(*AWSClient).emrconn
+		g, err := fetchEMRInstanceGroup(conn, rs.Primary.Attributes["cluster_id"], rs.Primary.ID)
 		if err != nil {
 			return fmt.Errorf("EMR error: %v", err)
 		}
@@ -176,6 +198,10 @@ resource "aws_security_group" "allow_all" {
 resource "aws_vpc" "main" {
   cidr_block           = "168.31.0.0/16"
   enable_dns_hostnames = true
+
+	tags {
+		Name = "tf_acc_emr_tests"
+	}
 }
 
 resource "aws_subnet" "main" {
@@ -375,7 +401,17 @@ func testAccAWSEmrInstanceGroupConfig(r int) string {
 	resource "aws_emr_instance_group" "task" {
     cluster_id     = "${aws_emr_cluster.tf-test-cluster.id}"
     instance_count = 1
-    instance_type  = "m3.xlarge"
+    instance_type  = "m1.small"
+  }
+	`, r, r, r, r, r, r)
+}
+
+func testAccAWSEmrInstanceGroupConfig_zero_count(r int) string {
+	return fmt.Sprintf(testAccAWSEmrInstanceGroupBase+`
+	resource "aws_emr_instance_group" "task" {
+    cluster_id     = "${aws_emr_cluster.tf-test-cluster.id}"
+    instance_count = 0
+    instance_type  = "m1.small"
   }
 	`, r, r, r, r, r, r)
 }