1package cli
2
3import (
4	"flag"
5	"fmt"
6	"time"
7)
8
9// DurationFlag is a flag with type time.Duration (see https://golang.org/pkg/time/#ParseDuration)
10type DurationFlag struct {
11	Name        string
12	Usage       string
13	EnvVar      string
14	FilePath    string
15	Required    bool
16	Hidden      bool
17	Value       time.Duration
18	Destination *time.Duration
19}
20
21// String returns a readable representation of this value
22// (for usage defaults)
23func (f DurationFlag) String() string {
24	return FlagStringer(f)
25}
26
27// GetName returns the name of the flag
28func (f DurationFlag) GetName() string {
29	return f.Name
30}
31
32// IsRequired returns whether or not the flag is required
33func (f DurationFlag) IsRequired() bool {
34	return f.Required
35}
36
37// TakesValue returns true of the flag takes a value, otherwise false
38func (f DurationFlag) TakesValue() bool {
39	return true
40}
41
42// GetUsage returns the usage string for the flag
43func (f DurationFlag) GetUsage() string {
44	return f.Usage
45}
46
47// GetValue returns the flags value as string representation and an empty
48// string if the flag takes no value at all.
49func (f DurationFlag) GetValue() string {
50	return f.Value.String()
51}
52
53// Duration looks up the value of a local DurationFlag, returns
54// 0 if not found
55func (c *Context) Duration(name string) time.Duration {
56	return lookupDuration(name, c.flagSet)
57}
58
59// GlobalDuration looks up the value of a global DurationFlag, returns
60// 0 if not found
61func (c *Context) GlobalDuration(name string) time.Duration {
62	if fs := lookupGlobalFlagSet(name, c); fs != nil {
63		return lookupDuration(name, fs)
64	}
65	return 0
66}
67
68// Apply populates the flag given the flag set and environment
69// Ignores errors
70func (f DurationFlag) Apply(set *flag.FlagSet) {
71	_ = f.ApplyWithError(set)
72}
73
74// ApplyWithError populates the flag given the flag set and environment
75func (f DurationFlag) ApplyWithError(set *flag.FlagSet) error {
76	if envVal, ok := flagFromFileEnv(f.FilePath, f.EnvVar); ok {
77		envValDuration, err := time.ParseDuration(envVal)
78		if err != nil {
79			return fmt.Errorf("could not parse %s as duration for flag %s: %s", envVal, f.Name, err)
80		}
81
82		f.Value = envValDuration
83	}
84
85	eachName(f.Name, func(name string) {
86		if f.Destination != nil {
87			set.DurationVar(f.Destination, name, f.Value, f.Usage)
88			return
89		}
90		set.Duration(name, f.Value, f.Usage)
91	})
92
93	return nil
94}
95
96func lookupDuration(name string, set *flag.FlagSet) time.Duration {
97	f := set.Lookup(name)
98	if f != nil {
99		parsed, err := time.ParseDuration(f.Value.String())
100		if err != nil {
101			return 0
102		}
103		return parsed
104	}
105	return 0
106}
107