func()

in network.go [326:382]

• 35 lines of code
• 7 McCabe index (conditional complexity)

func (cniConf CNIConfiguration) invokeCNI(ctx context.Context, logger *log.Entry) (*types.Result, error, []func() error) {
	var cleanupFuncs []func() error

	cniPlugin := libcni.NewCNIConfigWithCacheDir(cniConf.BinPath, cniConf.CacheDir, nil)

	networkConf := cniConf.NetworkConfig

	var err error

	if networkConf == nil {
		networkConf, err = libcni.LoadConfList(cniConf.ConfDir, cniConf.NetworkName)
		if err != nil {
			return nil, errors.Wrapf(err, "failed to load CNI configuration from dir %q for network %q",
				cniConf.ConfDir, cniConf.NetworkName), cleanupFuncs
		}
	}

	runtimeConf := cniConf.asCNIRuntimeConf()

	delNetworkFunc := func() error {
		err := cniPlugin.DelNetworkList(ctx, networkConf, runtimeConf)
		if err != nil {
			return errors.Wrapf(err, "failed to delete CNI network list %q", cniConf.NetworkName)
		}
		return nil
	}

	// Try deleting the network in case it already exists, which can happen if there is
	// a crash before cleanup from a previous invocations. If it doesn't exist,
	// well-behaved CNI plugins should treat this as a no-op without returning an error
	// (resulting also in a nil error here).
	// We can be reasonably sure any previous VM that was using this network is gone due
	// to earlier validation that the VM's socket path does not already exists.
	err = delNetworkFunc()
	if err != nil {
		errMsg := fmt.Sprintf("failed to delete pre-existing CNI network %+v", cniConf)
		// We are checking Force parameter to choose, should we fail with error
		// or continue execution with just logging error
		if !cniConf.Force {
			// something actually went wrong deleting the network, return an error and Force wasn't used so we don't
			// try to create a new network on top of a possibly half-deleted previous one.
			return nil, errors.Wrap(err, errMsg), cleanupFuncs
		}
		logger.Error(err, errMsg)
	}

	// Append cleanup of the network list before calling AddNetworkList to handle
	// case where AddNetworkList fails but leaves intermediate resources around like
	// devices and ip allocations.
	cleanupFuncs = append(cleanupFuncs, delNetworkFunc)
	cniResult, err := cniPlugin.AddNetworkList(ctx, networkConf, runtimeConf)
	if err != nil {
		return nil, errors.Wrap(err, "failed to create CNI network"), cleanupFuncs
	}

	return &cniResult, nil, cleanupFuncs
}