package cli import ( "flag" "fmt" "time" ) // DurationFlag is a flag with type time.Duration (see https://golang.org/pkg/time/#ParseDuration) type DurationFlag struct { Name string Aliases []string Usage string EnvVars []string FilePath string Required bool Hidden bool Value time.Duration DefaultText string Destination *time.Duration HasBeenSet bool } // IsSet returns whether or not the flag has been set through env or file func (f *DurationFlag) IsSet() bool { return f.HasBeenSet } // String returns a readable representation of this value // (for usage defaults) func (f *DurationFlag) String() string { return FlagStringer(f) } // Names returns the names of the flag func (f *DurationFlag) Names() []string { return flagNames(f.Name, f.Aliases) } // IsRequired returns whether or not the flag is required func (f *DurationFlag) IsRequired() bool { return f.Required } // TakesValue returns true of the flag takes a value, otherwise false func (f *DurationFlag) TakesValue() bool { return true } // GetUsage returns the usage string for the flag func (f *DurationFlag) GetUsage() string { return f.Usage } // GetValue returns the flags value as string representation and an empty // string if the flag takes no value at all. func (f *DurationFlag) GetValue() string { return f.Value.String() } // Apply populates the flag given the flag set and environment func (f *DurationFlag) Apply(set *flag.FlagSet) error { if val, ok := flagFromEnvOrFile(f.EnvVars, f.FilePath); ok { if val != "" { valDuration, err := time.ParseDuration(val) if err != nil { return fmt.Errorf("could not parse %q as duration value for flag %s: %s", val, f.Name, err) } f.Value = valDuration f.HasBeenSet = true } } for _, name := range f.Names() { if f.Destination != nil { set.DurationVar(f.Destination, name, f.Value, f.Usage) continue } set.Duration(name, f.Value, f.Usage) } return nil } // Duration looks up the value of a local DurationFlag, returns // 0 if not found func (c *Context) Duration(name string) time.Duration { if fs := c.lookupFlagSet(name); fs != nil { return lookupDuration(name, fs) } return 0 } func lookupDuration(name string, set *flag.FlagSet) time.Duration { f := set.Lookup(name) if f != nil { parsed, err := time.ParseDuration(f.Value.String()) if err != nil { return 0 } return parsed } return 0 }