[#1425] Avoid panic in Kea commands creation

Author: msiodelski

backend/appctrl/kea/subnetcmds.go

@@ -1,8 +1,6 @@
 package keactrl
 
 import (
-	"fmt"
-
 	keaconfig "isc.org/stork/appcfg/kea"
 )
 
@@ -71,16 +69,13 @@ func NewCommandNetwork6SubnetDel(sharedNetworkName string, localSubnetID int64,
 }
 
 // Creates network4-subnet-del or network6-subnet-del depending on the family.
-// It panics if the family is neither 4 nor 6.
 func NewCommandNetworkSubnetDel(family int, sharedNetworkName string, localSubnetID int64, daemonNames ...DaemonName) *Command {
 	var commandName CommandName
 	switch family {
 	case 4:
 		commandName = Network4SubnetDel
-	case 6:
-		commandName = Network6SubnetDel
 	default:
-		panic(fmt.Sprintf("invalid family %d", family))
+		commandName = Network6SubnetDel
 	}
 	return NewCommandBase(commandName, daemonNames...).
 		WithArgument("id", localSubnetID).
@@ -113,10 +108,8 @@ func NewCommandSubnetDel(family int, subnet *keaconfig.SubnetCmdsDeletedSubnet,
 	switch family {
 	case 4:
 		commandName = Subnet4Del
-	case 6:
-		commandName = Subnet6Del
 	default:
-		panic(fmt.Sprintf("invalid family %d", family))
+		commandName = Subnet6Del
 	}
 	return NewCommandBase(commandName, daemonNames...).
 		WithArgument("id", subnet.ID)

backend/appctrl/kea/subnetcmds_test.go

@@ -156,24 +156,19 @@ func TestNewCommandNetworkSubnetDelFamily4(t *testing.T) {
 
 // Tests network6-subnet-del command.
 func TestNewCommandNetworkSubnetDelFamily6(t *testing.T) {
-	command := NewCommandNetworkSubnetDel(6, "foo", 123, DHCPv6)
-	require.NotNil(t, command)
-	require.JSONEq(t, `{
+	// The network6-subnet-del command should be returned for different families.
+	for family := range []int64{6, 1, 0} {
+		command := NewCommandNetworkSubnetDel(family, "foo", 123, DHCPv6)
+		require.NotNil(t, command)
+		require.JSONEq(t, `{
 		"command": "network6-subnet-del",
 		"service": ["dhcp6"],
 		"arguments": {
 			"id": 123,
 			"name": "foo"
 		}
 	}`, command.Marshal())
-}
-
-// Test that the function creating network4-subnet-del or network6-subnet-del
-// panics when the family is invalid.
-func TestNewCommandNetworkSubnetDelInvalidFamily(t *testing.T) {
-	require.Panics(t, func() {
-		_ = NewCommandNetworkSubnetDel(0, "foo", 123, DHCPv4)
-	})
+	}
 }
 
 // Tests subnet4-add command.
@@ -269,27 +264,20 @@ func TestNewCommandSubnetDelFamily4(t *testing.T) {
 
 // Tests subnet6-del command.
 func TestNewCommandSubnetDelFamily6(t *testing.T) {
-	command := NewCommandSubnetDel(6, &keaconfig.SubnetCmdsDeletedSubnet{
-		ID: 4,
-	}, "dhcp6")
-	require.NotNil(t, command)
-	require.JSONEq(t, `{
+	// The subnet6-del command should be returned for different families.
+	for family := range []int64{6, 1, 0} {
+		command := NewCommandSubnetDel(family, &keaconfig.SubnetCmdsDeletedSubnet{
+			ID: 4,
+		}, "dhcp6")
+		require.NotNil(t, command)
+		require.JSONEq(t, `{
 		"command": "subnet6-del",
 		"service": ["dhcp6"],
 		"arguments": {
 			"id": 4
 		}
 	}`, command.Marshal())
-}
-
-// Test that the function returning subnet4-del or subnet6-del command
-// panics when the family is invalid.
-func TestNewCommandSubnetDelInvalidFamily(t *testing.T) {
-	require.Panics(t, func() {
-		_ = NewCommandSubnetDel(123, &keaconfig.SubnetCmdsDeletedSubnet{
-			ID: 2,
-		}, DHCPv4)
-	})
+	}
 }
 
 // Tests subnet4-update command.