Function updateNetworks

cli/command/service/update.go:1309–1359

(ctx context.Context, apiClient client.NetworkAPIClient, flags *pflag.FlagSet, spec *swarm.ServiceSpec)

}

func updateNetworks(ctx context.Context, apiClient client.NetworkAPIClient, flags *pflag.FlagSet, spec *swarm.ServiceSpec) error {
	// spec.TaskTemplate.Networks takes precedence over the deprecated
	// spec.Networks field. If spec.Network is in use, we'll migrate those
	// values to spec.TaskTemplate.Networks.
	specNetworks := spec.TaskTemplate.Networks

	toRemove := buildToRemoveSet(flags, flagNetworkRemove)
	idsToRemove := make(map[string]struct{})
	for networkIDOrName := range toRemove {
		nw, err := apiClient.NetworkInspect(ctx, networkIDOrName, client.NetworkInspectOptions{Scope: "swarm"})
		if err != nil {
			return err
		}
		idsToRemove[nw.Network.ID] = struct{}{}
	}

	existingNetworks := make(map[string]struct{})
	var newNetworks []swarm.NetworkAttachmentConfig
	for _, nw := range specNetworks {
		if _, exists := idsToRemove[nw.Target]; exists {
			continue
		}

		newNetworks = append(newNetworks, nw)
		existingNetworks[nw.Target] = struct{}{}
	}

	if flags.Changed(flagNetworkAdd) {
		values := flags.Lookup(flagNetworkAdd).Value.(*opts.NetworkOpt)
		networks := convertNetworks(*values)
		for _, nw := range networks {
			nwID, err := resolveNetworkID(ctx, apiClient, nw.Target)
			if err != nil {
				return err
			}
			if _, exists := existingNetworks[nwID]; exists {
				return fmt.Errorf("service is already attached to network %s", nw.Target)
			}
			nw.Target = nwID
			newNetworks = append(newNetworks, nw)
			existingNetworks[nw.Target] = struct{}{}
		}
	}

	sort.Slice(newNetworks, func(i, j int) bool {
		return newNetworks[i].Target < newNetworks[j].Target
	})

	spec.TaskTemplate.Networks = newNetworks
	return nil
}

// updateCredSpecConfig updates the value of the credential spec Config field
// to the config ID if the credential spec has changed. it mutates the passed