func()

in pkg/aws/ec2/instance.go [281:314]

• 26 lines of code
• 8 McCabe index (conditional complexity)

func (i *ec2Instance) updateCurrentSubnetAndCidrBlock(ec2APIHelper api.EC2APIHelper) error {
	// Custom networking is being used on node, point the current subnet ID, CIDR block and
	// instance security group to the one's present in the Custom networking spec
	if i.newCustomNetworkingSubnetID != "" {
		if i.newCustomNetworkingSecurityGroups != nil && len(i.newCustomNetworkingSecurityGroups) > 0 {
			i.currentInstanceSecurityGroups = i.newCustomNetworkingSecurityGroups
		} else {
			// when security groups are not specified in ENIConfig, use the primary network interface SG as per custom networking documentation
			i.currentInstanceSecurityGroups = i.primaryENISecurityGroups
		}
		// Only get the subnet CIDR block again if the subnet ID has changed
		if i.newCustomNetworkingSubnetID != i.currentSubnetID {
			customSubnet, err := ec2APIHelper.GetSubnet(&i.newCustomNetworkingSubnetID)
			if err != nil {
				return err
			}
			if customSubnet == nil || customSubnet.CidrBlock == nil {
				return fmt.Errorf("failed to find subnet %s", i.newCustomNetworkingSubnetID)
			}
			i.currentSubnetID = i.newCustomNetworkingSubnetID
			i.currentSubnetCIDRBlock = *customSubnet.CidrBlock
			// NOTE: IPv6 does not support custom networking
		}
	} else {
		// Custom networking in not being used, point to the primary network interface security group and
		// subnet details
		i.currentSubnetID = i.instanceSubnetID
		i.currentSubnetCIDRBlock = i.instanceSubnetCidrBlock
		i.currentSubnetV6CIDRBlock = i.instanceSubnetV6CidrBlock
		i.currentInstanceSecurityGroups = i.primaryENISecurityGroups
	}

	return nil
}