func()

in plugins/vpc-branch-eni/plugin/commands.go [187:265]
62 lines of code
12 McCabe index (conditional complexity)

func (plugin *Plugin) Del(args *cniSkel.CmdArgs) error {
	// Parse network configuration.
	netConfig, err := config.New(args)
	if err != nil {
		log.Errorf("Failed to parse netconfig from args: %v.", err)
		return err
	}

	log.Infof("Executing DEL with netconfig: %+v.", netConfig)

	// Derive names from CNI network config.
	var branchName string
	if netConfig.InterfaceType == config.IfTypeVLAN {
		branchName = args.IfName
	} else {
		// Find the trunk link name if not known.
		if netConfig.TrunkName == "" {
			trunk, err := eni.NewTrunk("", netConfig.TrunkMACAddress, eni.TrunkIsolationModeVLAN)
			if err != nil {
				// Log and ignore the failure.
				log.Errorf("Failed to find trunk with MAC address %v: %v.", netConfig.TrunkMACAddress, err)
				return nil
			}
			netConfig.TrunkName = trunk.GetLinkName()
		}
		branchName = fmt.Sprintf(branchLinkNameFormat, netConfig.TrunkName, netConfig.BranchVlanID)
	}
	tapBridgeName := fmt.Sprintf(bridgeNameFormat, netConfig.BranchVlanID)
	tapLinkName := args.IfName

	// Search for the target network namespace.
	netns, err := netns.GetNetNS(args.Netns)
	if err == nil {
		// In target network namespace...
		err = netns.Run(func() error {
			if netConfig.InterfaceType == config.IfTypeMACVTAP ||
				netConfig.InterfaceType == config.IfTypeTAP {
				// Delete the tap link.
				la := netlink.NewLinkAttrs()
				la.Name = tapLinkName
				tapLink := &netlink.Tuntap{LinkAttrs: la}
				log.Infof("Deleting tap link: %v.", tapLinkName)
				err = netlink.LinkDel(tapLink)
				if err != nil {
					log.Errorf("Failed to delete tap link: %v.", err)
				}
			}

			// Delete the branch link.
			la := netlink.NewLinkAttrs()
			la.Name = branchName
			branchLink := &netlink.Vlan{LinkAttrs: la}
			log.Infof("Deleting branch link: %v.", branchName)
			err = netlink.LinkDel(branchLink)
			if err != nil {
				log.Errorf("Failed to delete branch link: %v.", err)
			}

			if netConfig.InterfaceType == config.IfTypeTAP {
				// Delete the tap bridge.
				la = netlink.NewLinkAttrs()
				la.Name = tapBridgeName
				tapBridge := &netlink.Bridge{LinkAttrs: la}
				log.Infof("Deleting tap bridge: %v.", tapBridgeName)
				err = netlink.LinkDel(tapBridge)
				if err != nil {
					log.Errorf("Failed to delete tap bridge: %v.", err)
				}
			}

			return nil
		})
	} else {
		// Log and ignore the failure. DEL can be called multiple times and thus must be idempotent.
		log.Errorf("Failed to find netns %s, ignoring: %v.", args.Netns, err)
	}

	return nil
}