func Enum(val string, enumValMap map[string]int32) (int32, error) {
	e, ok := enumValMap[val]
	if ok {
		return e, nil
	}
	i, err := Int32(val)
	if err != nil {
		return 0, fmt.Errorf("%s is not valid", val)
	}
	for _, v := range enumValMap {
		if v == i {
			return i, nil
		}
	}
	return 0, fmt.Errorf("%s is not valid", val)
}
Enum converts the given string into an int32 that should be type casted into the
correct enum proto type.
package runtime
import (
	"encoding/base64"
	"fmt"
	"strconv"
	"strings"
	"github.com/golang/protobuf/jsonpb"
	"github.com/golang/protobuf/ptypes/duration"
	"github.com/golang/protobuf/ptypes/timestamp"
	"github.com/golang/protobuf/ptypes/wrappers"
)
func String(val string) (string, error) {
	return val, nil
}
func StringSlice(val, sep string) ([]string, error) {
	return strings.Split(val, sep), nil
}
func Bool(val string) (bool, error) {
	return strconv.ParseBool(val)
}
func BoolSlice(val, sep string) ([]bool, error) {
	s := strings.Split(val, sep)
	values := make([]bool, len(s))
	for i, v := range s {
		value, err := Bool(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Float64(val string) (float64, error) {
	return strconv.ParseFloat(val, 64)
}
func Float64Slice(val, sep string) ([]float64, error) {
	s := strings.Split(val, sep)
	values := make([]float64, len(s))
	for i, v := range s {
		value, err := Float64(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Float32(val string) (float32, error) {
	f, err := strconv.ParseFloat(val, 32)
	if err != nil {
		return 0, err
	}
	return float32(f), nil
}
func Float32Slice(val, sep string) ([]float32, error) {
	s := strings.Split(val, sep)
	values := make([]float32, len(s))
	for i, v := range s {
		value, err := Float32(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Int64(val string) (int64, error) {
	return strconv.ParseInt(val, 0, 64)
}
func Int64Slice(val, sep string) ([]int64, error) {
	s := strings.Split(val, sep)
	values := make([]int64, len(s))
	for i, v := range s {
		value, err := Int64(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Int32(val string) (int32, error) {
	i, err := strconv.ParseInt(val, 0, 32)
	if err != nil {
		return 0, err
	}
	return int32(i), nil
}
func Int32Slice(val, sep string) ([]int32, error) {
	s := strings.Split(val, sep)
	values := make([]int32, len(s))
	for i, v := range s {
		value, err := Int32(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Uint64(val string) (uint64, error) {
	return strconv.ParseUint(val, 0, 64)
}
func Uint64Slice(val, sep string) ([]uint64, error) {
	s := strings.Split(val, sep)
	values := make([]uint64, len(s))
	for i, v := range s {
		value, err := Uint64(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Uint32(val string) (uint32, error) {
	i, err := strconv.ParseUint(val, 0, 32)
	if err != nil {
		return 0, err
	}
	return uint32(i), nil
}
func Uint32Slice(val, sep string) ([]uint32, error) {
	s := strings.Split(val, sep)
	values := make([]uint32, len(s))
	for i, v := range s {
		value, err := Uint32(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Bytes(val string) ([]byte, error) {
	b, err := base64.StdEncoding.DecodeString(val)
	if err != nil {
		b, err = base64.URLEncoding.DecodeString(val)
		if err != nil {
			return nil, err
		}
	}
	return b, nil
}
func BytesSlice(val, sep string) ([][]byte, error) {
	s := strings.Split(val, sep)
	values := make([][]byte, len(s))
	for i, v := range s {
		value, err := Bytes(v)
		if err != nil {
			return values, err
		}
		values[i] = value
	}
	return values, nil
}
func Timestamp(val string) (*timestamp.Timestamp, error) {
	var r timestamp.Timestamp
	err := jsonpb.UnmarshalString(val, &r)
	if err != nil {
		return nil, err
	}
	return &r, nil
}
func Duration(val string) (*duration.Duration, error) {
	var r duration.Duration
	err := jsonpb.UnmarshalString(val, &r)
	if err != nil {
		return nil, err
	}
	return &r, nil
}