generic_filter.go

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package impl

import (
	hessian "github.com/apache/dubbo-go-hessian2"
	"reflect"
	"strings"
)
import (
	"github.com/apache/dubbo-go/common/constant"
	"github.com/apache/dubbo-go/common/extension"
	"github.com/apache/dubbo-go/filter"
	"github.com/apache/dubbo-go/protocol"
	invocation2 "github.com/apache/dubbo-go/protocol/invocation"
)

const (
	GENERIC = "generic"
)

func init() {
	extension.SetFilter(GENERIC, GetGenericFilter)
}

//  when do a generic invoke, struct need to be map

type GenericFilter struct{}

func (ef *GenericFilter) Invoke(invoker protocol.Invoker, invocation protocol.Invocation) protocol.Result {
	if invocation.MethodName() == constant.GENERIC && len(invocation.Arguments()) == 3 {
		var (
			oldArguments = invocation.Arguments()
		)
		newArguments := []interface{}{
			oldArguments[0],
			oldArguments[1],
			hessian.Object(struct2MapAll(oldArguments[2])),
		}
		newInvocation := invocation2.NewRPCInvocation(invocation.MethodName(), newArguments, invocation.Attachments())
		return invoker.Invoke(newInvocation)
	}
	return invoker.Invoke(invocation)
}

func (ef *GenericFilter) OnResponse(result protocol.Result, invoker protocol.Invoker, invocation protocol.Invocation) protocol.Result {
	return result
}

func GetGenericFilter() filter.Filter {
	return &GenericFilter{}
}
func struct2MapAll(obj interface{}) map[string]interface{} {
	result := make(map[string]interface{})
	if obj == nil {
		return result
	}
	t := reflect.TypeOf(obj)
	v := reflect.ValueOf(obj)

	if reflect.TypeOf(obj).Kind() == reflect.Struct {
		for i := 0; i < t.NumField(); i++ {
			if v.Field(i).Kind() == reflect.Struct {
				if v.Field(i).CanInterface() {
					result[headerAtoa(t.Field(i).Name)] = struct2MapAll(v.Field(i).Interface())
				}
			} else {
				if v.Field(i).CanInterface() {
					if tagName := t.Field(i).Tag.Get("m"); tagName == "" {
						result[headerAtoa(t.Field(i).Name)] = v.Field(i).Interface()
					} else {
						result[tagName] = v.Field(i).Interface()
					}
				}
			}
		}
	}
	return result
}
func headerAtoa(a string) (b string) {
	b = strings.ToLower(a[:1]) + a[1:]
	return
}