micro/register/extractor.go
Vasiliy Tolstov ebd8ddf05b move to v4
Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
2023-04-11 22:21:25 +03:00

103 lines
1.7 KiB
Go

package register
import (
"fmt"
"reflect"
"unicode"
"unicode/utf8"
"go.unistack.org/micro/v4/metadata"
)
// ExtractValue from reflect.Type from specified depth
func ExtractValue(v reflect.Type, d int) string {
if d == 3 {
return ""
}
if v == nil {
return ""
}
if v.Kind() == reflect.Ptr {
v = v.Elem()
}
// slices and maps don't have a defined name
if (v.Kind() == reflect.Slice || v.Kind() == reflect.Map) || len(v.Name()) == 0 {
return ""
}
// get the rune character
a, _ := utf8.DecodeRuneInString(string(v.Name()[0]))
// crude check for is unexported field
if unicode.IsLower(a) {
return ""
}
return v.Name()
}
// ExtractEndpoint extract *Endpoint from reflect.Method
func ExtractEndpoint(method reflect.Method) *Endpoint {
if method.PkgPath != "" {
return nil
}
var rspType, reqType reflect.Type
var stream bool
mt := method.Type
switch mt.NumIn() {
case 3:
reqType = mt.In(1)
rspType = mt.In(2)
case 4:
reqType = mt.In(2)
rspType = mt.In(3)
default:
return nil
}
// are we dealing with a stream?
switch rspType.Kind() {
case reflect.Func, reflect.Interface:
stream = true
}
request := ExtractValue(reqType, 0)
response := ExtractValue(rspType, 0)
if request == "" || response == "" {
return nil
}
ep := &Endpoint{
Name: method.Name,
Request: request,
Response: response,
Metadata: metadata.New(0),
}
if stream {
ep.Metadata.Set("stream", fmt.Sprintf("%v", stream))
}
return ep
}
// ExtractSubValue exctact *Value from reflect.Type
func ExtractSubValue(typ reflect.Type) string {
var reqType reflect.Type
switch typ.NumIn() {
case 1:
reqType = typ.In(0)
case 2:
reqType = typ.In(1)
case 3:
reqType = typ.In(2)
default:
return ""
}
return ExtractValue(reqType, 0)
}