Check oncall rolling_users shift does not include empty group (#1685)

* Check oncall rolling_users shift does not include empty group

* Add test for error case

Author: matiasb

internal/resources/oncall/resource_shift.go

@@ -292,6 +292,12 @@ func resourceOnCallShiftCreate(ctx context.Context, d *schema.ResourceData, clie
 	rollingUsersData, rollingUsersOk := d.GetOk(rollingUsers)
 	if rollingUsersOk {
 		if typeData == rollingUsers {
+			listSet := rollingUsersData.([]interface{})
+			for _, set := range listSet {
+				if set == nil {
+					return diag.Errorf("`rolling_users` can not include an empty group")
+				}
+			}
 			rollingUsersDataSlice := common.ListOfSetsToStringSlice(rollingUsersData.([]interface{}))
 			createOptions.RollingUsers = &rollingUsersDataSlice
 		} else {
@@ -419,6 +425,12 @@ func resourceOnCallShiftUpdate(ctx context.Context, d *schema.ResourceData, clie
 	rollingUsersData, rollingUsersOk := d.GetOk(rollingUsers)
 	if rollingUsersOk {
 		if typeData == rollingUsers {
+			listSet := rollingUsersData.([]interface{})
+			for _, set := range listSet {
+				if set == nil {
+					return diag.Errorf("`rolling_users` can not include an empty group")
+				}
+			}
 			rollingUsersDataSlice := common.ListOfSetsToStringSlice(rollingUsersData.([]interface{}))
 			updateOptions.RollingUsers = &rollingUsersDataSlice
 		} else {

internal/resources/oncall/resource_shift_test.go

@@ -2,6 +2,7 @@ package oncall_test
 
 import (
 	"fmt"
+	"regexp"
 	"testing"
 
 	onCallAPI "github.com/grafana/amixr-api-go-client"
@@ -46,6 +47,17 @@ func TestAccOnCallOnCallShift_basic(t *testing.T) {
 					resource.TestCheckResourceAttr("grafana_oncall_on_call_shift.test-acc-on_call_shift", "frequency", "hourly"),
 				),
 			},
+			{
+				Config: testAccOnCallOnCallShiftEmptyRollingUsers(scheduleName, shiftName),
+				Check: resource.ComposeTestCheckFunc(
+					testAccCheckOnCallOnCallShiftResourceExists("grafana_oncall_on_call_shift.test-acc-on_call_shift"),
+					resource.TestCheckResourceAttr("grafana_oncall_on_call_shift.test-acc-on_call_shift", "rolling_users.#", "0"),
+				),
+			},
+			{
+				Config:      testAccOnCallOnCallShiftRollingUsersEmptyGroup(scheduleName, shiftName),
+				ExpectError: regexp.MustCompile("Error: `rolling_users` can not include an empty group"),
+			},
 			{
 				Config: testAccOnCallOnCallShiftConfigSingle(scheduleName, shiftName),
 				Check: resource.ComposeTestCheckFunc(
@@ -113,6 +125,52 @@ resource "grafana_oncall_on_call_shift" "test-acc-on_call_shift" {
 `, scheduleName, shiftName)
 }
 
+func testAccOnCallOnCallShiftEmptyRollingUsers(scheduleName, shiftName string) string {
+	return fmt.Sprintf(`
+resource "grafana_oncall_schedule" "test-acc-schedule" {
+	type = "calendar"
+	name = "%s"
+	time_zone = "UTC"
+}
+
+resource "grafana_oncall_on_call_shift" "test-acc-on_call_shift" {
+	name = "%s"
+	type = "rolling_users"
+	start = "2020-09-04T16:00:00"
+	duration = 3600
+	level = 1
+	frequency = "weekly"
+	week_start = "SU"
+	interval = 2
+	by_day = ["MO", "FR"]
+	rolling_users = []
+}
+`, scheduleName, shiftName)
+}
+
+func testAccOnCallOnCallShiftRollingUsersEmptyGroup(scheduleName, shiftName string) string {
+	return fmt.Sprintf(`
+resource "grafana_oncall_schedule" "test-acc-schedule" {
+	type = "calendar"
+	name = "%s"
+	time_zone = "UTC"
+}
+
+resource "grafana_oncall_on_call_shift" "test-acc-on_call_shift" {
+	name = "%s"
+	type = "rolling_users"
+	start = "2020-09-04T16:00:00"
+	duration = 3600
+	level = 1
+	frequency = "weekly"
+	week_start = "SU"
+	interval = 2
+	by_day = ["MO", "FR"]
+	rolling_users = [[]]
+}
+`, scheduleName, shiftName)
+}
+
 func testAccOnCallOnCallShiftConfigSingle(scheduleName, shiftName string) string {
 	return fmt.Sprintf(`
 resource "grafana_oncall_schedule" "test-acc-schedule" {