gotty/vendor/github.com/codegangsta/cli/flag.go
2016-04-13 16:17:57 +09:00

498 lines
12 KiB
Go

package cli
import (
"flag"
"fmt"
"os"
"strconv"
"strings"
"time"
)
// This flag enables bash-completion for all commands and subcommands
var BashCompletionFlag = BoolFlag{
Name: "generate-bash-completion",
}
// This flag prints the version for the application
var VersionFlag = BoolFlag{
Name: "version, v",
Usage: "print the version",
}
// This flag prints the help for all commands and subcommands
// Set to the zero value (BoolFlag{}) to disable flag -- keeps subcommand
// unless HideHelp is set to true)
var HelpFlag = BoolFlag{
Name: "help, h",
Usage: "show help",
}
// Flag is a common interface related to parsing flags in cli.
// For more advanced flag parsing techniques, it is recomended that
// this interface be implemented.
type Flag interface {
fmt.Stringer
// Apply Flag settings to the given flag set
Apply(*flag.FlagSet)
getName() string
}
func flagSet(name string, flags []Flag) *flag.FlagSet {
set := flag.NewFlagSet(name, flag.ContinueOnError)
for _, f := range flags {
f.Apply(set)
}
return set
}
func eachName(longName string, fn func(string)) {
parts := strings.Split(longName, ",")
for _, name := range parts {
name = strings.Trim(name, " ")
fn(name)
}
}
// Generic is a generic parseable type identified by a specific flag
type Generic interface {
Set(value string) error
String() string
}
// GenericFlag is the flag type for types implementing Generic
type GenericFlag struct {
Name string
Value Generic
Usage string
EnvVar string
}
// String returns the string representation of the generic flag to display the
// help text to the user (uses the String() method of the generic flag to show
// the value)
func (f GenericFlag) String() string {
return withEnvHint(f.EnvVar, fmt.Sprintf("%s%s \"%v\"\t%v", prefixFor(f.Name), f.Name, f.Value, f.Usage))
}
// Apply takes the flagset and calls Set on the generic flag with the value
// provided by the user for parsing by the flag
func (f GenericFlag) Apply(set *flag.FlagSet) {
val := f.Value
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
val.Set(envVal)
break
}
}
}
eachName(f.Name, func(name string) {
set.Var(f.Value, name, f.Usage)
})
}
func (f GenericFlag) getName() string {
return f.Name
}
// StringSlice is an opaque type for []string to satisfy flag.Value
type StringSlice []string
// Set appends the string value to the list of values
func (f *StringSlice) Set(value string) error {
*f = append(*f, value)
return nil
}
// String returns a readable representation of this value (for usage defaults)
func (f *StringSlice) String() string {
return fmt.Sprintf("%s", *f)
}
// Value returns the slice of strings set by this flag
func (f *StringSlice) Value() []string {
return *f
}
// StringSlice is a string flag that can be specified multiple times on the
// command-line
type StringSliceFlag struct {
Name string
Value *StringSlice
Usage string
EnvVar string
}
// String returns the usage
func (f StringSliceFlag) String() string {
firstName := strings.Trim(strings.Split(f.Name, ",")[0], " ")
pref := prefixFor(firstName)
return withEnvHint(f.EnvVar, fmt.Sprintf("%s [%v]\t%v", prefixedNames(f.Name), pref+firstName+" option "+pref+firstName+" option", f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f StringSliceFlag) Apply(set *flag.FlagSet) {
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
newVal := &StringSlice{}
for _, s := range strings.Split(envVal, ",") {
s = strings.TrimSpace(s)
newVal.Set(s)
}
f.Value = newVal
break
}
}
}
eachName(f.Name, func(name string) {
if f.Value == nil {
f.Value = &StringSlice{}
}
set.Var(f.Value, name, f.Usage)
})
}
func (f StringSliceFlag) getName() string {
return f.Name
}
// StringSlice is an opaque type for []int to satisfy flag.Value
type IntSlice []int
// Set parses the value into an integer and appends it to the list of values
func (f *IntSlice) Set(value string) error {
tmp, err := strconv.Atoi(value)
if err != nil {
return err
} else {
*f = append(*f, tmp)
}
return nil
}
// String returns a readable representation of this value (for usage defaults)
func (f *IntSlice) String() string {
return fmt.Sprintf("%d", *f)
}
// Value returns the slice of ints set by this flag
func (f *IntSlice) Value() []int {
return *f
}
// IntSliceFlag is an int flag that can be specified multiple times on the
// command-line
type IntSliceFlag struct {
Name string
Value *IntSlice
Usage string
EnvVar string
}
// String returns the usage
func (f IntSliceFlag) String() string {
firstName := strings.Trim(strings.Split(f.Name, ",")[0], " ")
pref := prefixFor(firstName)
return withEnvHint(f.EnvVar, fmt.Sprintf("%s [%v]\t%v", prefixedNames(f.Name), pref+firstName+" option "+pref+firstName+" option", f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f IntSliceFlag) Apply(set *flag.FlagSet) {
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
newVal := &IntSlice{}
for _, s := range strings.Split(envVal, ",") {
s = strings.TrimSpace(s)
err := newVal.Set(s)
if err != nil {
fmt.Fprintf(os.Stderr, err.Error())
}
}
f.Value = newVal
break
}
}
}
eachName(f.Name, func(name string) {
if f.Value == nil {
f.Value = &IntSlice{}
}
set.Var(f.Value, name, f.Usage)
})
}
func (f IntSliceFlag) getName() string {
return f.Name
}
// BoolFlag is a switch that defaults to false
type BoolFlag struct {
Name string
Usage string
EnvVar string
}
// String returns a readable representation of this value (for usage defaults)
func (f BoolFlag) String() string {
return withEnvHint(f.EnvVar, fmt.Sprintf("%s\t%v", prefixedNames(f.Name), f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f BoolFlag) Apply(set *flag.FlagSet) {
val := false
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
envValBool, err := strconv.ParseBool(envVal)
if err == nil {
val = envValBool
}
break
}
}
}
eachName(f.Name, func(name string) {
set.Bool(name, val, f.Usage)
})
}
func (f BoolFlag) getName() string {
return f.Name
}
// BoolTFlag this represents a boolean flag that is true by default, but can
// still be set to false by --some-flag=false
type BoolTFlag struct {
Name string
Usage string
EnvVar string
}
// String returns a readable representation of this value (for usage defaults)
func (f BoolTFlag) String() string {
return withEnvHint(f.EnvVar, fmt.Sprintf("%s\t%v", prefixedNames(f.Name), f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f BoolTFlag) Apply(set *flag.FlagSet) {
val := true
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
envValBool, err := strconv.ParseBool(envVal)
if err == nil {
val = envValBool
break
}
}
}
}
eachName(f.Name, func(name string) {
set.Bool(name, val, f.Usage)
})
}
func (f BoolTFlag) getName() string {
return f.Name
}
// StringFlag represents a flag that takes as string value
type StringFlag struct {
Name string
Value string
Usage string
EnvVar string
}
// String returns the usage
func (f StringFlag) String() string {
var fmtString string
fmtString = "%s %v\t%v"
if len(f.Value) > 0 {
fmtString = "%s \"%v\"\t%v"
} else {
fmtString = "%s %v\t%v"
}
return withEnvHint(f.EnvVar, fmt.Sprintf(fmtString, prefixedNames(f.Name), f.Value, f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f StringFlag) Apply(set *flag.FlagSet) {
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
f.Value = envVal
break
}
}
}
eachName(f.Name, func(name string) {
set.String(name, f.Value, f.Usage)
})
}
func (f StringFlag) getName() string {
return f.Name
}
// IntFlag is a flag that takes an integer
// Errors if the value provided cannot be parsed
type IntFlag struct {
Name string
Value int
Usage string
EnvVar string
}
// String returns the usage
func (f IntFlag) String() string {
return withEnvHint(f.EnvVar, fmt.Sprintf("%s \"%v\"\t%v", prefixedNames(f.Name), f.Value, f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f IntFlag) Apply(set *flag.FlagSet) {
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
envValInt, err := strconv.ParseInt(envVal, 0, 64)
if err == nil {
f.Value = int(envValInt)
break
}
}
}
}
eachName(f.Name, func(name string) {
set.Int(name, f.Value, f.Usage)
})
}
func (f IntFlag) getName() string {
return f.Name
}
// DurationFlag is a flag that takes a duration specified in Go's duration
// format: https://golang.org/pkg/time/#ParseDuration
type DurationFlag struct {
Name string
Value time.Duration
Usage string
EnvVar string
}
// String returns a readable representation of this value (for usage defaults)
func (f DurationFlag) String() string {
return withEnvHint(f.EnvVar, fmt.Sprintf("%s \"%v\"\t%v", prefixedNames(f.Name), f.Value, f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f DurationFlag) Apply(set *flag.FlagSet) {
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
envValDuration, err := time.ParseDuration(envVal)
if err == nil {
f.Value = envValDuration
break
}
}
}
}
eachName(f.Name, func(name string) {
set.Duration(name, f.Value, f.Usage)
})
}
func (f DurationFlag) getName() string {
return f.Name
}
// Float64Flag is a flag that takes an float value
// Errors if the value provided cannot be parsed
type Float64Flag struct {
Name string
Value float64
Usage string
EnvVar string
}
// String returns the usage
func (f Float64Flag) String() string {
return withEnvHint(f.EnvVar, fmt.Sprintf("%s \"%v\"\t%v", prefixedNames(f.Name), f.Value, f.Usage))
}
// Apply populates the flag given the flag set and environment
func (f Float64Flag) Apply(set *flag.FlagSet) {
if f.EnvVar != "" {
for _, envVar := range strings.Split(f.EnvVar, ",") {
envVar = strings.TrimSpace(envVar)
if envVal := os.Getenv(envVar); envVal != "" {
envValFloat, err := strconv.ParseFloat(envVal, 10)
if err == nil {
f.Value = float64(envValFloat)
}
}
}
}
eachName(f.Name, func(name string) {
set.Float64(name, f.Value, f.Usage)
})
}
func (f Float64Flag) getName() string {
return f.Name
}
func prefixFor(name string) (prefix string) {
if len(name) == 1 {
prefix = "-"
} else {
prefix = "--"
}
return
}
func prefixedNames(fullName string) (prefixed string) {
parts := strings.Split(fullName, ",")
for i, name := range parts {
name = strings.Trim(name, " ")
prefixed += prefixFor(name) + name
if i < len(parts)-1 {
prefixed += ", "
}
}
return
}
func withEnvHint(envVar, str string) string {
envText := ""
if envVar != "" {
envText = fmt.Sprintf(" [$%s]", strings.Join(strings.Split(envVar, ","), ", $"))
}
return str + envText
}