urfave-cli/flag_int64_slice.go
Mostyn Bramley-Moore 500d6b04e6 Report the source of a value when we cannot parse it
If you allow a flag to be set from environment variables or files and
a parse error occurs from one of them, it is very useful for the error
message to mention where the value came from.

Without this, it can be difficult to notice an error caused by an
unexpected environment variable being set.

Implements #1167.
2020-11-03 23:57:00 +01:00

160 lines
3.6 KiB
Go

package cli
import (
"encoding/json"
"flag"
"fmt"
"strconv"
"strings"
)
// Int64Slice wraps []int64 to satisfy flag.Value
type Int64Slice struct {
slice []int64
hasBeenSet bool
}
// NewInt64Slice makes an *Int64Slice with default values
func NewInt64Slice(defaults ...int64) *Int64Slice {
return &Int64Slice{slice: append([]int64{}, defaults...)}
}
// Set parses the value into an integer and appends it to the list of values
func (i *Int64Slice) Set(value string) error {
if !i.hasBeenSet {
i.slice = []int64{}
i.hasBeenSet = true
}
if strings.HasPrefix(value, slPfx) {
// Deserializing assumes overwrite
_ = json.Unmarshal([]byte(strings.Replace(value, slPfx, "", 1)), &i.slice)
i.hasBeenSet = true
return nil
}
tmp, err := strconv.ParseInt(value, 0, 64)
if err != nil {
return err
}
i.slice = append(i.slice, tmp)
return nil
}
// String returns a readable representation of this value (for usage defaults)
func (i *Int64Slice) String() string {
return fmt.Sprintf("%#v", i.slice)
}
// Serialize allows Int64Slice to fulfill Serializer
func (i *Int64Slice) Serialize() string {
jsonBytes, _ := json.Marshal(i.slice)
return fmt.Sprintf("%s%s", slPfx, string(jsonBytes))
}
// Value returns the slice of ints set by this flag
func (i *Int64Slice) Value() []int64 {
return i.slice
}
// Get returns the slice of ints set by this flag
func (i *Int64Slice) Get() interface{} {
return *i
}
// Int64SliceFlag is a flag with type *Int64Slice
type Int64SliceFlag struct {
Name string
Aliases []string
Usage string
EnvVars []string
FilePath string
Required bool
Hidden bool
Value *Int64Slice
DefaultText string
HasBeenSet bool
}
// IsSet returns whether or not the flag has been set through env or file
func (f *Int64SliceFlag) IsSet() bool {
return f.HasBeenSet
}
// String returns a readable representation of this value
// (for usage defaults)
func (f *Int64SliceFlag) String() string {
return FlagStringer(f)
}
// Names returns the names of the flag
func (f *Int64SliceFlag) Names() []string {
return flagNames(f.Name, f.Aliases)
}
// IsRequired returns whether or not the flag is required
func (f *Int64SliceFlag) IsRequired() bool {
return f.Required
}
// TakesValue returns true of the flag takes a value, otherwise false
func (f *Int64SliceFlag) TakesValue() bool {
return true
}
// GetUsage returns the usage string for the flag
func (f Int64SliceFlag) 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 *Int64SliceFlag) GetValue() string {
if f.Value != nil {
return f.Value.String()
}
return ""
}
// Apply populates the flag given the flag set and environment
func (f *Int64SliceFlag) Apply(set *flag.FlagSet) error {
if val, ok, source := flagFromEnvOrFile(f.EnvVars, f.FilePath); ok {
f.Value = &Int64Slice{}
for _, s := range strings.Split(val, ",") {
if err := f.Value.Set(strings.TrimSpace(s)); err != nil {
return fmt.Errorf("could not parse %q as int64 slice value %s for flag %s: %s", val, source, f.Name, err)
}
}
f.HasBeenSet = true
}
for _, name := range f.Names() {
if f.Value == nil {
f.Value = &Int64Slice{}
}
set.Var(f.Value, name, f.Usage)
}
return nil
}
// Int64Slice looks up the value of a local Int64SliceFlag, returns
// nil if not found
func (c *Context) Int64Slice(name string) []int64 {
return lookupInt64Slice(name, c.flagSet)
}
func lookupInt64Slice(name string, set *flag.FlagSet) []int64 {
f := set.Lookup(name)
if f != nil {
if slice, ok := f.Value.(*Int64Slice); ok {
return slice.Value()
}
}
return nil
}