7bb19bef64
Go's time parsing uses UTC when the format doesn't have a tiemzone, and has even weirder behavior when it has a zone name but no numeric offset. A caller to `cast.ToTime` won't know if the returned time was explicitly in UTC, or defaulted there, so the caller cannot fix it. These new functions allow a user to supply a different timezone to default to, with nil using the local zone.
537 lines
13 KiB
Go
537 lines
13 KiB
Go
// Copyright © 2014 Steve Francia <spf@spf13.com>.
|
|
//
|
|
// Use of this source code is governed by an MIT-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package cast
|
|
|
|
import (
|
|
"fmt"
|
|
"html/template"
|
|
"reflect"
|
|
"strconv"
|
|
"strings"
|
|
"time"
|
|
|
|
jww "github.com/spf13/jwalterweatherman"
|
|
)
|
|
|
|
// ToTimeE casts an empty interface to time.Time.
|
|
func ToTimeE(i interface{}) (tim time.Time, err error) {
|
|
return ToTimeInDefaultLocationE(i, time.UTC)
|
|
}
|
|
|
|
// ToTimeInDefaultLocationE casts an empty interface to time.Time,
|
|
// interpreting inputs without a timezone to be in the given location,
|
|
// or the local timezone if nil.
|
|
func ToTimeInDefaultLocationE(i interface{}, location *time.Location) (tim time.Time, err error) {
|
|
i = indirect(i)
|
|
jww.DEBUG.Println("ToTimeE called on type:", reflect.TypeOf(i))
|
|
|
|
switch s := i.(type) {
|
|
case time.Time:
|
|
return s, nil
|
|
case string:
|
|
d, e := StringToDateInDefaultLocation(s, location)
|
|
if e == nil {
|
|
return d, nil
|
|
}
|
|
return time.Time{}, fmt.Errorf("Could not parse Date/Time format: %v\n", e)
|
|
default:
|
|
return time.Time{}, fmt.Errorf("Unable to Cast %#v to Time\n", i)
|
|
}
|
|
}
|
|
|
|
// ToDurationE casts an empty interface to time.Duration.
|
|
func ToDurationE(i interface{}) (d time.Duration, err error) {
|
|
i = indirect(i)
|
|
jww.DEBUG.Println("ToDurationE called on type:", reflect.TypeOf(i))
|
|
|
|
switch s := i.(type) {
|
|
case time.Duration:
|
|
return s, nil
|
|
case int64:
|
|
d = time.Duration(s)
|
|
return
|
|
case float64:
|
|
d = time.Duration(s)
|
|
return
|
|
case string:
|
|
d, err = time.ParseDuration(s)
|
|
return
|
|
default:
|
|
err = fmt.Errorf("Unable to Cast %#v to Duration\n", i)
|
|
return
|
|
}
|
|
}
|
|
|
|
// ToBoolE casts an empty interface to a bool.
|
|
func ToBoolE(i interface{}) (bool, error) {
|
|
i = indirect(i)
|
|
jww.DEBUG.Println("ToBoolE called on type:", reflect.TypeOf(i))
|
|
|
|
switch b := i.(type) {
|
|
case bool:
|
|
return b, nil
|
|
case nil:
|
|
return false, nil
|
|
case int:
|
|
if i.(int) != 0 {
|
|
return true, nil
|
|
}
|
|
return false, nil
|
|
case string:
|
|
return strconv.ParseBool(i.(string))
|
|
default:
|
|
return false, fmt.Errorf("Unable to Cast %#v to bool", i)
|
|
}
|
|
}
|
|
|
|
// ToFloat64E casts an empty interface to a float64.
|
|
func ToFloat64E(i interface{}) (float64, error) {
|
|
i = indirect(i)
|
|
jww.DEBUG.Println("ToFloat64E called on type:", reflect.TypeOf(i))
|
|
|
|
switch s := i.(type) {
|
|
case float64:
|
|
return s, nil
|
|
case float32:
|
|
return float64(s), nil
|
|
case int64:
|
|
return float64(s), nil
|
|
case int32:
|
|
return float64(s), nil
|
|
case int16:
|
|
return float64(s), nil
|
|
case int8:
|
|
return float64(s), nil
|
|
case int:
|
|
return float64(s), nil
|
|
case string:
|
|
v, err := strconv.ParseFloat(s, 64)
|
|
if err == nil {
|
|
return float64(v), nil
|
|
}
|
|
return 0.0, fmt.Errorf("Unable to Cast %#v to float", i)
|
|
default:
|
|
return 0.0, fmt.Errorf("Unable to Cast %#v to float", i)
|
|
}
|
|
}
|
|
|
|
// ToInt64E casts an empty interface to an int64.
|
|
func ToInt64E(i interface{}) (int64, error) {
|
|
i = indirect(i)
|
|
jww.DEBUG.Println("ToInt64E called on type:", reflect.TypeOf(i))
|
|
|
|
switch s := i.(type) {
|
|
case int64:
|
|
return s, nil
|
|
case int:
|
|
return int64(s), nil
|
|
case int32:
|
|
return int64(s), nil
|
|
case int16:
|
|
return int64(s), nil
|
|
case int8:
|
|
return int64(s), nil
|
|
case string:
|
|
v, err := strconv.ParseInt(s, 0, 0)
|
|
if err == nil {
|
|
return v, nil
|
|
}
|
|
return 0, fmt.Errorf("Unable to Cast %#v to int64", i)
|
|
case float64:
|
|
return int64(s), nil
|
|
case bool:
|
|
if bool(s) {
|
|
return int64(1), nil
|
|
}
|
|
return int64(0), nil
|
|
case nil:
|
|
return int64(0), nil
|
|
default:
|
|
return int64(0), fmt.Errorf("Unable to Cast %#v to int64", i)
|
|
}
|
|
}
|
|
|
|
// ToIntE casts an empty interface to an int.
|
|
func ToIntE(i interface{}) (int, error) {
|
|
i = indirect(i)
|
|
jww.DEBUG.Println("ToIntE called on type:", reflect.TypeOf(i))
|
|
|
|
switch s := i.(type) {
|
|
case int:
|
|
return s, nil
|
|
case int64:
|
|
return int(s), nil
|
|
case int32:
|
|
return int(s), nil
|
|
case int16:
|
|
return int(s), nil
|
|
case int8:
|
|
return int(s), nil
|
|
case string:
|
|
v, err := strconv.ParseInt(s, 0, 0)
|
|
if err == nil {
|
|
return int(v), nil
|
|
}
|
|
return 0, fmt.Errorf("Unable to Cast %#v to int", i)
|
|
case float64:
|
|
return int(s), nil
|
|
case bool:
|
|
if bool(s) {
|
|
return 1, nil
|
|
}
|
|
return 0, nil
|
|
case nil:
|
|
return 0, nil
|
|
default:
|
|
return 0, fmt.Errorf("Unable to Cast %#v to int", i)
|
|
}
|
|
}
|
|
|
|
// From html/template/content.go
|
|
// Copyright 2011 The Go Authors. All rights reserved.
|
|
// indirect returns the value, after dereferencing as many times
|
|
// as necessary to reach the base type (or nil).
|
|
func indirect(a interface{}) interface{} {
|
|
if a == nil {
|
|
return nil
|
|
}
|
|
if t := reflect.TypeOf(a); t.Kind() != reflect.Ptr {
|
|
// Avoid creating a reflect.Value if it's not a pointer.
|
|
return a
|
|
}
|
|
v := reflect.ValueOf(a)
|
|
for v.Kind() == reflect.Ptr && !v.IsNil() {
|
|
v = v.Elem()
|
|
}
|
|
return v.Interface()
|
|
}
|
|
|
|
// From html/template/content.go
|
|
// Copyright 2011 The Go Authors. All rights reserved.
|
|
// indirectToStringerOrError returns the value, after dereferencing as many times
|
|
// as necessary to reach the base type (or nil) or an implementation of fmt.Stringer
|
|
// or error,
|
|
func indirectToStringerOrError(a interface{}) interface{} {
|
|
if a == nil {
|
|
return nil
|
|
}
|
|
|
|
var errorType = reflect.TypeOf((*error)(nil)).Elem()
|
|
var fmtStringerType = reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
|
|
|
|
v := reflect.ValueOf(a)
|
|
for !v.Type().Implements(fmtStringerType) && !v.Type().Implements(errorType) && v.Kind() == reflect.Ptr && !v.IsNil() {
|
|
v = v.Elem()
|
|
}
|
|
return v.Interface()
|
|
}
|
|
|
|
// ToStringE casts an empty interface to a string.
|
|
func ToStringE(i interface{}) (string, error) {
|
|
i = indirectToStringerOrError(i)
|
|
jww.DEBUG.Println("ToStringE called on type:", reflect.TypeOf(i))
|
|
|
|
switch s := i.(type) {
|
|
case string:
|
|
return s, nil
|
|
case bool:
|
|
return strconv.FormatBool(s), nil
|
|
case float64:
|
|
return strconv.FormatFloat(i.(float64), 'f', -1, 64), nil
|
|
case int64:
|
|
return strconv.FormatInt(i.(int64), 10), nil
|
|
case int:
|
|
return strconv.FormatInt(int64(i.(int)), 10), nil
|
|
case []byte:
|
|
return string(s), nil
|
|
case template.HTML:
|
|
return string(s), nil
|
|
case template.URL:
|
|
return string(s), nil
|
|
case template.JS:
|
|
return string(s), nil
|
|
case template.CSS:
|
|
return string(s), nil
|
|
case template.HTMLAttr:
|
|
return string(s), nil
|
|
case nil:
|
|
return "", nil
|
|
case fmt.Stringer:
|
|
return s.String(), nil
|
|
case error:
|
|
return s.Error(), nil
|
|
default:
|
|
return "", fmt.Errorf("Unable to Cast %#v to string", i)
|
|
}
|
|
}
|
|
|
|
// ToStringMapStringE casts an empty interface to a map[string]string.
|
|
func ToStringMapStringE(i interface{}) (map[string]string, error) {
|
|
jww.DEBUG.Println("ToStringMapStringE called on type:", reflect.TypeOf(i))
|
|
|
|
var m = map[string]string{}
|
|
|
|
switch v := i.(type) {
|
|
case map[string]string:
|
|
return v, nil
|
|
case map[string]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToString(val)
|
|
}
|
|
return m, nil
|
|
case map[interface{}]string:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToString(val)
|
|
}
|
|
return m, nil
|
|
case map[interface{}]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToString(val)
|
|
}
|
|
return m, nil
|
|
default:
|
|
return m, fmt.Errorf("Unable to Cast %#v to map[string]string", i)
|
|
}
|
|
}
|
|
|
|
// ToStringMapStringSliceE casts an empty interface to a map[string][]string.
|
|
func ToStringMapStringSliceE(i interface{}) (map[string][]string, error) {
|
|
jww.DEBUG.Println("ToStringMapStringSliceE called on type:", reflect.TypeOf(i))
|
|
|
|
var m = map[string][]string{}
|
|
|
|
switch v := i.(type) {
|
|
case map[string][]string:
|
|
return v, nil
|
|
case map[string][]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToStringSlice(val)
|
|
}
|
|
return m, nil
|
|
case map[string]string:
|
|
for k, val := range v {
|
|
m[ToString(k)] = []string{val}
|
|
}
|
|
case map[string]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = []string{ToString(val)}
|
|
}
|
|
return m, nil
|
|
case map[interface{}][]string:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToStringSlice(val)
|
|
}
|
|
return m, nil
|
|
case map[interface{}]string:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToStringSlice(val)
|
|
}
|
|
return m, nil
|
|
case map[interface{}][]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToStringSlice(val)
|
|
}
|
|
return m, nil
|
|
case map[interface{}]interface{}:
|
|
for k, val := range v {
|
|
key, err := ToStringE(k)
|
|
if err != nil {
|
|
return m, fmt.Errorf("Unable to Cast %#v to map[string][]string", i)
|
|
}
|
|
value, err := ToStringSliceE(val)
|
|
if err != nil {
|
|
return m, fmt.Errorf("Unable to Cast %#v to map[string][]string", i)
|
|
}
|
|
m[key] = value
|
|
}
|
|
default:
|
|
return m, fmt.Errorf("Unable to Cast %#v to map[string][]string", i)
|
|
}
|
|
return m, nil
|
|
}
|
|
|
|
// ToStringMapBoolE casts an empty interface to a map[string]bool.
|
|
func ToStringMapBoolE(i interface{}) (map[string]bool, error) {
|
|
jww.DEBUG.Println("ToStringMapBoolE called on type:", reflect.TypeOf(i))
|
|
|
|
var m = map[string]bool{}
|
|
|
|
switch v := i.(type) {
|
|
case map[interface{}]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToBool(val)
|
|
}
|
|
return m, nil
|
|
case map[string]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = ToBool(val)
|
|
}
|
|
return m, nil
|
|
case map[string]bool:
|
|
return v, nil
|
|
default:
|
|
return m, fmt.Errorf("Unable to Cast %#v to map[string]bool", i)
|
|
}
|
|
}
|
|
|
|
// ToStringMapE casts an empty interface to a map[string]interface{}.
|
|
func ToStringMapE(i interface{}) (map[string]interface{}, error) {
|
|
jww.DEBUG.Println("ToStringMapE called on type:", reflect.TypeOf(i))
|
|
|
|
var m = map[string]interface{}{}
|
|
|
|
switch v := i.(type) {
|
|
case map[interface{}]interface{}:
|
|
for k, val := range v {
|
|
m[ToString(k)] = val
|
|
}
|
|
return m, nil
|
|
case map[string]interface{}:
|
|
return v, nil
|
|
default:
|
|
return m, fmt.Errorf("Unable to Cast %#v to map[string]interface{}", i)
|
|
}
|
|
}
|
|
|
|
// ToSliceE casts an empty interface to a []interface{}.
|
|
func ToSliceE(i interface{}) ([]interface{}, error) {
|
|
jww.DEBUG.Println("ToSliceE called on type:", reflect.TypeOf(i))
|
|
|
|
var s []interface{}
|
|
|
|
switch v := i.(type) {
|
|
case []interface{}:
|
|
for _, u := range v {
|
|
s = append(s, u)
|
|
}
|
|
return s, nil
|
|
case []map[string]interface{}:
|
|
for _, u := range v {
|
|
s = append(s, u)
|
|
}
|
|
return s, nil
|
|
default:
|
|
return s, fmt.Errorf("Unable to Cast %#v of type %v to []interface{}", i, reflect.TypeOf(i))
|
|
}
|
|
}
|
|
|
|
// ToStringSliceE casts an empty interface to a []string.
|
|
func ToStringSliceE(i interface{}) ([]string, error) {
|
|
jww.DEBUG.Println("ToStringSliceE called on type:", reflect.TypeOf(i))
|
|
|
|
var a []string
|
|
|
|
switch v := i.(type) {
|
|
case []interface{}:
|
|
for _, u := range v {
|
|
a = append(a, ToString(u))
|
|
}
|
|
return a, nil
|
|
case []string:
|
|
return v, nil
|
|
case string:
|
|
return strings.Fields(v), nil
|
|
case interface{}:
|
|
str, err := ToStringE(v)
|
|
if err != nil {
|
|
return a, fmt.Errorf("Unable to Cast %#v to []string", i)
|
|
}
|
|
return []string{str}, nil
|
|
default:
|
|
return a, fmt.Errorf("Unable to Cast %#v to []string", i)
|
|
}
|
|
}
|
|
|
|
// ToIntSliceE casts an empty interface to a []int.
|
|
func ToIntSliceE(i interface{}) ([]int, error) {
|
|
jww.DEBUG.Println("ToIntSliceE called on type:", reflect.TypeOf(i))
|
|
|
|
if i == nil {
|
|
return []int{}, fmt.Errorf("Unable to Cast %#v to []int", i)
|
|
}
|
|
|
|
switch v := i.(type) {
|
|
case []int:
|
|
return v, nil
|
|
}
|
|
|
|
kind := reflect.TypeOf(i).Kind()
|
|
switch kind {
|
|
case reflect.Slice, reflect.Array:
|
|
s := reflect.ValueOf(i)
|
|
a := make([]int, s.Len())
|
|
for j := 0; j < s.Len(); j++ {
|
|
val, err := ToIntE(s.Index(j).Interface())
|
|
if err != nil {
|
|
return []int{}, fmt.Errorf("Unable to Cast %#v to []int", i)
|
|
}
|
|
a[j] = val
|
|
}
|
|
return a, nil
|
|
default:
|
|
return []int{}, fmt.Errorf("Unable to Cast %#v to []int", i)
|
|
}
|
|
}
|
|
|
|
// StringToDate casts an empty interface to a time.Time.
|
|
func StringToDate(s string) (time.Time, error) {
|
|
return StringToDateInDefaultLocation(s, time.UTC)
|
|
}
|
|
|
|
// StringToDateInDefaultLocation casts an empty interface to a time.Time,
|
|
// interpreting inputs without a timezone to be in the given location,
|
|
// or the local timezone if nil.
|
|
func StringToDateInDefaultLocation(s string, location *time.Location) (time.Time, error) {
|
|
if location == nil {
|
|
location = time.Local
|
|
}
|
|
return parseDateWith(s, location, timeFormats)
|
|
}
|
|
|
|
type timeFormat struct {
|
|
format string
|
|
hasTimezone bool
|
|
}
|
|
|
|
var (
|
|
timeFormats = []timeFormat{
|
|
timeFormat{time.RFC3339, true},
|
|
timeFormat{"2006-01-02T15:04:05", false}, // iso8601 without timezone
|
|
timeFormat{time.RFC1123Z, true},
|
|
timeFormat{time.RFC1123, false},
|
|
timeFormat{time.RFC822Z, true},
|
|
timeFormat{time.RFC822, false},
|
|
timeFormat{time.ANSIC, false},
|
|
timeFormat{time.UnixDate, false},
|
|
timeFormat{time.RubyDate, true},
|
|
timeFormat{"2006-01-02 15:04:05Z07:00", true},
|
|
timeFormat{"02 Jan 06 15:04 MST", false},
|
|
timeFormat{"2006-01-02", false},
|
|
timeFormat{"02 Jan 2006", false},
|
|
timeFormat{"2006-01-02 15:04:05 -07:00", true},
|
|
timeFormat{"2006-01-02 15:04:05 -0700", true},
|
|
}
|
|
)
|
|
|
|
func parseDateWith(s string, defaultLocation *time.Location, formats []timeFormat) (d time.Time, e error) {
|
|
for _, format := range formats {
|
|
if d, e = time.Parse(format.format, s); e == nil {
|
|
|
|
// Some time formats have a zone name, but no offset, so it gets
|
|
// put in that zone name (not the default one passed in to us), but
|
|
// without that zone's offset. So set the location manually.
|
|
if !format.hasTimezone && defaultLocation != nil {
|
|
year, month, day := d.Date()
|
|
hour, min, sec := d.Clock()
|
|
d = time.Date(year, month, day, hour, min, sec, d.Nanosecond(), defaultLocation)
|
|
}
|
|
|
|
return
|
|
}
|
|
}
|
|
return d, fmt.Errorf("Unable to parse date: %s", s)
|
|
}
|