micro/registry/extractor.go
Vasiliy Tolstov 40b0870cf8
fix linting (#4)
Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>
2020-11-03 01:08:23 +03:00

124 lines
2.1 KiB
Go

package registry
import (
"fmt"
"reflect"
"strings"
)
// Extract *Value from reflect.Type
func ExtractValue(v reflect.Type, d int) *Value {
if d == 3 {
return nil
}
if v == nil {
return nil
}
if v.Kind() == reflect.Ptr {
v = v.Elem()
}
arg := &Value{
Name: v.Name(),
Type: v.Name(),
}
switch v.Kind() {
case reflect.Struct:
for i := 0; i < v.NumField(); i++ {
f := v.Field(i)
val := ExtractValue(f.Type, d+1)
if val == nil {
continue
}
// if we can find a json tag use it
if tags := f.Tag.Get("json"); len(tags) > 0 {
parts := strings.Split(tags, ",")
if parts[0] == "-" || parts[0] == "omitempty" {
continue
}
val.Name = parts[0]
}
// if there's no name default it
if len(val.Name) == 0 {
val.Name = v.Field(i).Name
}
arg.Values = append(arg.Values, val)
}
case reflect.Slice:
p := v.Elem()
if p.Kind() == reflect.Ptr {
p = p.Elem()
}
arg.Type = "[]" + p.Name()
}
return arg
}
// 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)
ep := &Endpoint{
Name: method.Name,
Request: request,
Response: response,
Metadata: make(map[string]string),
}
if stream {
ep.Metadata = map[string]string{
"stream": fmt.Sprintf("%v", stream),
}
}
return ep
}
// ExtractSubValue exctact *Value from reflect.Type
func ExtractSubValue(typ reflect.Type) *Value {
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 nil
}
return ExtractValue(reqType, 0)
}