package client import ( "errors" "fmt" "io" "io/ioutil" "os" "reflect" "strings" flag "github.com/docker/docker/pkg/mflag" ) // CallFunc provides environment specific call utility to invoke backend functions from UI type CallFunc func(string, string, interface{}, map[string][]string) (io.ReadCloser, int, error) // NetworkCli is the UI object for network subcmds type NetworkCli struct { out io.Writer err io.Writer call CallFunc } // NewNetworkCli is a conveninent function to create a NetworkCli object func NewNetworkCli(out, err io.Writer, call CallFunc) *NetworkCli { return &NetworkCli{ out: out, err: err, call: call, } } // getMethod is Borrowed from Docker UI which uses reflection to identify the UI Handler func (cli *NetworkCli) getMethod(args ...string) (func(string, ...string) error, bool) { camelArgs := make([]string, len(args)) for i, s := range args { if len(s) == 0 { return nil, false } camelArgs[i] = strings.ToUpper(s[:1]) + strings.ToLower(s[1:]) } methodName := "Cmd" + strings.Join(camelArgs, "") method := reflect.ValueOf(cli).MethodByName(methodName) if !method.IsValid() { return nil, false } return method.Interface().(func(string, ...string) error), true } // Cmd is borrowed from Docker UI and acts as the entry point for network UI commands. // network UI commands are designed to be invoked from multiple parent chains func (cli *NetworkCli) Cmd(chain string, args ...string) error { var errStr string if len(args) > 1 { method, exists := cli.getMethod(args[:2]...) if exists { return method(chain, args[2:]...) } } if len(args) > 0 { method, exists := cli.getMethod(args[0]) if !exists { errStr = fmt.Sprintf("%s: '%s' is not a %s command. See '%s --help'.\n", chain, args[0], chain, chain) fmt.Fprintf(cli.err, errStr) return errors.New(errStr) } return method(chain, args[1:]...) } errStr = fmt.Sprintf("'%s' is not a valid command. See '%s --help'.\n", chain, chain) fmt.Fprintf(cli.err, errStr) return errors.New(errStr) } // Subcmd is borrowed from Docker UI and performs the same function of configuring the subCmds func (cli *NetworkCli) Subcmd(chain, name, signature, description string, exitOnError bool) *flag.FlagSet { var errorHandling flag.ErrorHandling if exitOnError { errorHandling = flag.ExitOnError } else { errorHandling = flag.ContinueOnError } flags := flag.NewFlagSet(name, errorHandling) flags.Usage = func() { options := "" if signature != "" { signature = " " + signature } if flags.FlagCountUndeprecated() > 0 { options = " [OPTIONS]" } fmt.Fprintf(cli.out, "\nUsage: %s %s%s%s\n\n%s\n\n", chain, name, options, signature, description) flags.SetOutput(cli.out) flags.PrintDefaults() os.Exit(0) } return flags } func readBody(stream io.ReadCloser, statusCode int, err error) ([]byte, int, error) { if stream != nil { defer stream.Close() } if err != nil { return nil, statusCode, err } body, err := ioutil.ReadAll(stream) if err != nil { return nil, -1, err } return body, statusCode, nil }