traefik/pkg/config/parser/element_fill.go
Fernandez Ludovic 4c5e7a238d chore: go module
2019-08-12 05:06:04 -07:00

327 lines
7.2 KiB
Go

package parser
import (
"fmt"
"reflect"
"strconv"
"strings"
"time"
"github.com/containous/traefik/v2/pkg/types"
)
type initializer interface {
SetDefaults()
}
// Fill populates the fields of the element using the information in node.
func Fill(element interface{}, node *Node) error {
if element == nil || node == nil {
return nil
}
if node.Kind == 0 {
return fmt.Errorf("missing node type: %s", node.Name)
}
root := reflect.ValueOf(element)
if root.Kind() == reflect.Struct {
return fmt.Errorf("struct are not supported, use pointer instead")
}
return fill(root.Elem(), node)
}
func fill(field reflect.Value, node *Node) error {
// related to allow-empty tag
if node.Disabled {
return nil
}
switch field.Kind() {
case reflect.String:
field.SetString(node.Value)
return nil
case reflect.Bool:
val, err := strconv.ParseBool(node.Value)
if err != nil {
return err
}
field.SetBool(val)
return nil
case reflect.Int8:
return setInt(field, node.Value, 8)
case reflect.Int16:
return setInt(field, node.Value, 16)
case reflect.Int32:
return setInt(field, node.Value, 32)
case reflect.Int64, reflect.Int:
return setInt(field, node.Value, 64)
case reflect.Uint8:
return setUint(field, node.Value, 8)
case reflect.Uint16:
return setUint(field, node.Value, 16)
case reflect.Uint32:
return setUint(field, node.Value, 32)
case reflect.Uint64, reflect.Uint:
return setUint(field, node.Value, 64)
case reflect.Float32:
return setFloat(field, node.Value, 32)
case reflect.Float64:
return setFloat(field, node.Value, 64)
case reflect.Struct:
return setStruct(field, node)
case reflect.Ptr:
return setPtr(field, node)
case reflect.Map:
return setMap(field, node)
case reflect.Slice:
return setSlice(field, node)
default:
return nil
}
}
func setPtr(field reflect.Value, node *Node) error {
if field.IsNil() {
field.Set(reflect.New(field.Type().Elem()))
if field.Type().Implements(reflect.TypeOf((*initializer)(nil)).Elem()) {
method := field.MethodByName("SetDefaults")
if method.IsValid() {
method.Call([]reflect.Value{})
}
}
}
return fill(field.Elem(), node)
}
func setStruct(field reflect.Value, node *Node) error {
for _, child := range node.Children {
fd := field.FieldByName(child.FieldName)
zeroValue := reflect.Value{}
if fd == zeroValue {
return fmt.Errorf("field not found, node: %s (%s)", child.Name, child.FieldName)
}
err := fill(fd, child)
if err != nil {
return err
}
}
return nil
}
func setSlice(field reflect.Value, node *Node) error {
if field.Type().Elem().Kind() == reflect.Struct ||
field.Type().Elem().Kind() == reflect.Ptr && field.Type().Elem().Elem().Kind() == reflect.Struct {
return setSliceStruct(field, node)
}
if len(node.Value) == 0 {
return nil
}
values := strings.Split(node.Value, ",")
slice := reflect.MakeSlice(field.Type(), len(values), len(values))
field.Set(slice)
for i := 0; i < len(values); i++ {
value := strings.TrimSpace(values[i])
switch field.Type().Elem().Kind() {
case reflect.String:
field.Index(i).SetString(value)
case reflect.Int:
val, err := strconv.ParseInt(value, 10, 64)
if err != nil {
return err
}
field.Index(i).SetInt(val)
case reflect.Int8:
err := setInt(field.Index(i), value, 8)
if err != nil {
return err
}
case reflect.Int16:
err := setInt(field.Index(i), value, 16)
if err != nil {
return err
}
case reflect.Int32:
err := setInt(field.Index(i), value, 32)
if err != nil {
return err
}
case reflect.Int64:
err := setInt(field.Index(i), value, 64)
if err != nil {
return err
}
case reflect.Uint:
val, err := strconv.ParseUint(value, 10, 64)
if err != nil {
return err
}
field.Index(i).SetUint(val)
case reflect.Uint8:
err := setUint(field.Index(i), value, 8)
if err != nil {
return err
}
case reflect.Uint16:
err := setUint(field.Index(i), value, 16)
if err != nil {
return err
}
case reflect.Uint32:
err := setUint(field.Index(i), value, 32)
if err != nil {
return err
}
case reflect.Uint64:
err := setUint(field.Index(i), value, 64)
if err != nil {
return err
}
case reflect.Float32:
err := setFloat(field.Index(i), value, 32)
if err != nil {
return err
}
case reflect.Float64:
err := setFloat(field.Index(i), value, 64)
if err != nil {
return err
}
case reflect.Bool:
val, err := strconv.ParseBool(value)
if err != nil {
return err
}
field.Index(i).SetBool(val)
default:
return fmt.Errorf("unsupported type: %s", field.Type().Elem())
}
}
return nil
}
func setSliceStruct(field reflect.Value, node *Node) error {
if node.Tag.Get(TagLabelSliceAsStruct) != "" {
return setSliceAsStruct(field, node)
}
field.Set(reflect.MakeSlice(field.Type(), len(node.Children), len(node.Children)))
for i, child := range node.Children {
// use Ptr to allow "SetDefaults"
value := reflect.New(reflect.PtrTo(field.Type().Elem()))
err := setPtr(value, child)
if err != nil {
return err
}
field.Index(i).Set(value.Elem().Elem())
}
return nil
}
func setSliceAsStruct(field reflect.Value, node *Node) error {
if len(node.Children) == 0 {
return fmt.Errorf("invalid slice: node %s", node.Name)
}
// use Ptr to allow "SetDefaults"
value := reflect.New(reflect.PtrTo(field.Type().Elem()))
err := setPtr(value, node)
if err != nil {
return err
}
elem := value.Elem().Elem()
field.Set(reflect.MakeSlice(field.Type(), 1, 1))
field.Index(0).Set(elem)
return nil
}
func setMap(field reflect.Value, node *Node) error {
if field.IsNil() {
field.Set(reflect.MakeMap(field.Type()))
}
for _, child := range node.Children {
ptrValue := reflect.New(reflect.PtrTo(field.Type().Elem()))
err := fill(ptrValue, child)
if err != nil {
return err
}
value := ptrValue.Elem().Elem()
key := reflect.ValueOf(child.Name)
field.SetMapIndex(key, value)
}
return nil
}
func setInt(field reflect.Value, value string, bitSize int) error {
switch field.Type() {
case reflect.TypeOf(types.Duration(0)):
return setDuration(field, value, bitSize, time.Second)
case reflect.TypeOf(time.Duration(0)):
return setDuration(field, value, bitSize, time.Nanosecond)
default:
val, err := strconv.ParseInt(value, 10, bitSize)
if err != nil {
return err
}
field.Set(reflect.ValueOf(val).Convert(field.Type()))
return nil
}
}
func setDuration(field reflect.Value, value string, bitSize int, defaultUnit time.Duration) error {
val, err := strconv.ParseInt(value, 10, bitSize)
if err == nil {
field.Set(reflect.ValueOf(time.Duration(val) * defaultUnit).Convert(field.Type()))
return nil
}
duration, err := time.ParseDuration(value)
if err != nil {
return err
}
field.Set(reflect.ValueOf(duration).Convert(field.Type()))
return nil
}
func setUint(field reflect.Value, value string, bitSize int) error {
val, err := strconv.ParseUint(value, 10, bitSize)
if err != nil {
return err
}
field.Set(reflect.ValueOf(val).Convert(field.Type()))
return nil
}
func setFloat(field reflect.Value, value string, bitSize int) error {
val, err := strconv.ParseFloat(value, bitSize)
if err != nil {
return err
}
field.Set(reflect.ValueOf(val).Convert(field.Type()))
return nil
}