urfave-cli/flag_duration.go
Dmitry Kutakov 8c28ae347a
refactor flag names - make it more explicitly
avoid the using 'reflect' package while getting flag names
2019-12-29 08:58:12 +01:00

106 lines
2.4 KiB
Go

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 := lookupFlagSet(name, c); 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
}