Golang util.ErrCast函数代码示例

// Parse parses the input commandline string (cmd, flags, and args).
// returns the corresponding command Request object.
func Parse(input []string, stdin *os.File, root *cmds.Command) (cmds.Request, *cmds.Command, []string, error) {
	path, opts, stringVals, cmd, err := parseOpts(input, root)
	if err != nil {
		return nil, nil, path, err
	}

	optDefs, err := root.GetOptions(path)
	if err != nil {
		return nil, cmd, path, err
	}

	req, err := cmds.NewRequest(path, opts, nil, nil, cmd, optDefs)
	if err != nil {
		return nil, cmd, path, err
	}

	// if -r is provided, and it is associated with the package builtin
	// recursive path option, allow recursive file paths
	recursiveOpt := req.Option(cmds.RecShort)
	recursive := false
	if recursiveOpt != nil && recursiveOpt.Definition() == cmds.OptionRecursivePath {
		recursive, _, err = recursiveOpt.Bool()
		if err != nil {
			return req, nil, nil, u.ErrCast()
		}
	}

	// if '--hidden' is provided, enumerate hidden paths
	hiddenOpt := req.Option("hidden")
	hidden := false
	if hiddenOpt != nil {
		hidden, _, err = hiddenOpt.Bool()
		if err != nil {
			return req, nil, nil, u.ErrCast()
		}
	}

	stringArgs, fileArgs, err := parseArgs(stringVals, stdin, cmd.Arguments, recursive, hidden, root)
	if err != nil {
		return req, cmd, path, err
	}
	req.SetArguments(stringArgs)

	if len(fileArgs) > 0 {
		file := files.NewSliceFile("", "", fileArgs)
		req.SetFiles(file)
	}

	err = cmd.CheckArguments(req)
	if err != nil {
		return req, cmd, path, err
	}

	return req, cmd, path, nil
}

func objectMarshaler(res cmds.Response) (io.Reader, error) {
	o, ok := res.Output().(*Object)
	if !ok {
		return nil, u.ErrCast()
	}

	return strings.NewReader(o.Hash + "\n"), nil
}

// value accessor methods, gets the value as a certain type
func (ov OptionValue) Bool() (value bool, found bool, err error) {
	if !ov.found {
		return false, false, nil
	}
	val, ok := ov.value.(bool)
	if !ok {
		err = util.ErrCast()
	}
	return val, ov.found, err
}

func (ov OptionValue) String() (value string, found bool, err error) {
	if !ov.found {
		return "", false, nil
	}
	val, ok := ov.value.(string)
	if !ok {
		err = util.ErrCast()
	}
	return val, ov.found, err
}

func (ov OptionValue) Float() (value float64, found bool, err error) {
	if !ov.found {
		return 0, false, nil
	}
	val, ok := ov.value.(float64)
	if !ok {
		err = util.ErrCast()
	}
	return val, ov.found, err
}

func (ov OptionValue) Uint() (value uint, found bool, err error) {
	if !ov.found {
		return 0, false, nil
	}
	val, ok := ov.value.(uint)
	if !ok {
		err = util.ErrCast()
	}
	return val, ov.found, err
}

func bootstrapMarshaler(res cmds.Response) (io.Reader, error) {
	v, ok := res.Output().(*BootstrapOutput)
	if !ok {
		return nil, u.ErrCast()
	}

	buf := new(bytes.Buffer)
	err := bootstrapWritePeers(buf, "", v.Peers)
	return buf, err
}

func (r *request) ConvertOptions() error {
	for k, v := range r.options {
		opt, ok := r.optionDefs[k]
		if !ok {
			continue
		}

		kind := reflect.TypeOf(v).Kind()
		if kind != opt.Type() {
			if kind == String {
				convert := converters[opt.Type()]
				str, ok := v.(string)
				if !ok {
					return u.ErrCast()
				}
				val, err := convert(str)
				if err != nil {
					value := fmt.Sprintf("value '%v'", v)
					if len(str) == 0 {
						value = "empty value"
					}
					return fmt.Errorf("Could not convert %s to type '%s' (for option '-%s')",
						value, opt.Type().String(), k)
				}
				r.options[k] = val

			} else {
				return fmt.Errorf("Option '%s' should be type '%s', but got type '%s'",
					k, opt.Type().String(), kind.String())
			}
		} else {
			r.options[k] = v
		}

		for _, name := range opt.Names() {
			if _, ok := r.options[name]; name != k && ok {
				return fmt.Errorf("Duplicate command options were provided ('%s' and '%s')",
					k, name)
			}
		}
	}

	return nil
}

		go func() {
			defer close(outChan)
			if err := addAllAndPin(req.Files()); err != nil {
				res.SetError(err, cmds.ErrNormal)
				return
			}

		}()
	},
	PostRun: func(req cmds.Request, res cmds.Response) {
		if res.Error() != nil {
			return
		}
		outChan, ok := res.Output().(<-chan interface{})
		if !ok {
			res.SetError(u.ErrCast(), cmds.ErrNormal)
			return
		}
		res.SetOutput(nil)

		quiet, _, err := req.Option("quiet").Bool()
		if err != nil {
			res.SetError(u.ErrCast(), cmds.ErrNormal)
			return
		}

		size := int64(0)
		s, found := req.Values()["size"]
		if found {
			size = s.(int64)
		}

		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		node, err := core.Resolve(req.Context(), n, p)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		key, err := node.Key()
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		res.SetOutput(&ResolvedPath{path.FromKey(key)})
	},
	Marshalers: cmds.MarshalerMap{
		cmds.Text: func(res cmds.Response) (io.Reader, error) {
			output, ok := res.Output().(*ResolvedPath)
			if !ok {
				return nil, u.ErrCast()
			}
			return strings.NewReader(output.Path.String() + "\n"), nil
		},
	},
	Type: ResolvedPath{},
}

	},
	Run: func(req cmds.Request, res cmds.Response) {
		nd, err := req.InvocContext().GetNode()
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}

		if !nd.OnlineMode() {
			res.SetError(errNotOnline, cmds.ErrClient)
			return
		}

		bs, ok := nd.Exchange.(*bitswap.Bitswap)
		if !ok {
			res.SetError(u.ErrCast(), cmds.ErrNormal)
			return
		}

		var ks []key.Key
		for _, arg := range req.Arguments() {
			dec := key.B58KeyDecode(arg)
			if dec == "" {
				res.SetError(fmt.Errorf("incorrectly formatted key: %s", arg), cmds.ErrNormal)
				return
			}

			ks = append(ks, dec)
		}

		bs.CancelWants(ks)

		cmds.BoolOption("recursive", "r", "Resolve until the result is not a DNS link."),
	},
	Run: func(req cmds.Request, res cmds.Response) {

		recursive, _, _ := req.Option("recursive").Bool()
		name := req.Arguments()[0]
		resolver := namesys.NewDNSResolver()

		depth := 1
		if recursive {
			depth = namesys.DefaultDepthLimit
		}
		output, err := resolver.ResolveN(req.Context(), name, depth)
		if err != nil {
			res.SetError(err, cmds.ErrNormal)
			return
		}
		res.SetOutput(&ResolvedPath{output})
	},
	Marshalers: cmds.MarshalerMap{
		cmds.Text: func(res cmds.Response) (io.Reader, error) {
			output, ok := res.Output().(*ResolvedPath)
			if !ok {
				return nil, util.ErrCast()
			}
			return strings.NewReader(output.Path.String() + "\n"), nil
		},
	},
	Type: ResolvedPath{},
}