ftr: add json struct parser to support cli tool

go.mod

 module github.com/dubbogo/gost
 
 require (
+	github.com/apache/dubbo-go-hessian2 v1.8.0-rc1
+	github.com/buger/jsonparser v1.0.0
 	github.com/davecgh/go-spew v1.1.1
 	github.com/k0kubun/colorstring v0.0.0-20150214042306-9440f1994b88 // indirect
 	github.com/k0kubun/pp v3.0.1+incompatible

go.sum

+github.com/apache/dubbo-go-hessian2 v1.8.0-rc1 h1:IJyHFLhJrNE5VdKtN6/0n7rJqCjHraHuORcHkZhwQyQ=
+github.com/apache/dubbo-go-hessian2 v1.8.0-rc1/go.mod h1:7rEw9guWABQa6Aqb8HeZcsYPHsOS7XT1qtJvkmI6c5w=
+github.com/buger/jsonparser v1.0.0 h1:etJTGF5ESxjI0Ic2UaLQs2LQQpa8G9ykQScukbh4L8A=
+github.com/buger/jsonparser v1.0.0/go.mod h1:tgcrVJ81GPSF0mz+0nu1Xaz0fazGPrmmJfJtxjbHhUQ=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/dubbogo/gost v1.9.0/go.mod h1:pPTjVyoJan3aPxBPNUX0ADkXjPibLo+/Ib0/fADXSG8=
 github.com/k0kubun/colorstring v0.0.0-20150214042306-9440f1994b88 h1:uC1QfSlInpQF+M0ao65imhwqKnz3Q2z/d8PWZRMQvDM=
 github.com/k0kubun/colorstring v0.0.0-20150214042306-9440f1994b88/go.mod h1:3w7q1U84EfirKl04SVQ/s7nPm1ZPhiXd34z40TNz36k=
 github.com/k0kubun/pp v3.0.1+incompatible h1:3tqvf7QgUnZ5tXO6pNAZlrvHgl6DvifjDrd9g2S9Z40=
@@ -10,12 +15,14 @@ github.com/mattn/go-colorable v0.1.7 h1:bQGKb3vps/j0E9GfJQ03JyhRuxsvdAanXlT9BTw3
 github.com/mattn/go-colorable v0.1.7/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-isatty v0.0.12 h1:wuysRhFDzyxgEmMf5xjvJ2M9dZoWAXNNr5LSBS7uHXY=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.6.1 h1:hDPOHmpOpP40lSULcqw7IrRb/u7w6RpDC9399XyoNd0=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42 h1:vEOn+mP2zCOVzKckCZy6YsCtDblrpj/w7B9nxGNELpg=
@@ -24,5 +31,6 @@ golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae h1:/WDfKMnPU+m5M4xB+6x4kaepx
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

json-struct-parser/parser.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 json_struct_parser
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"reflect"
+	"strconv"
+	"strings"
+	"time"
+
+	hessian2 "github.com/apache/dubbo-go-hessian2"
+	"github.com/buger/jsonparser"
+)
+
+type jsonStructParser struct {
+	structFields   []reflect.StructField
+	valueMap       map[string]string
+	subObjValueMap map[string]reflect.Value
+}
+
+func newJsonStructParser() *jsonStructParser {
+	return &jsonStructParser{
+		structFields:   make([]reflect.StructField, 0),
+		valueMap:       make(map[string]string),
+		subObjValueMap: make(map[string]reflect.Value),
+	}
+}
+
+func init() {
+	defaultJsonStructParser = newJsonStructParser()
+}
+
+var defaultJsonStructParser *jsonStructParser
+
+func JsonFile2Interface(path string) (interface{}, error) {
+	defer func() {
+		defaultJsonStructParser = newJsonStructParser()
+	}()
+	return defaultJsonStructParser.Jsonfile2Struct(path)
+}
+
+func RemoveTargetNameField(v interface{}, targetName string) interface{} {
+	defer func() {
+		defaultJsonStructParser = newJsonStructParser()
+	}()
+	return defaultJsonStructParser.RemoveTargetNameField(v, targetName)
+}
+
+func (jsp *jsonStructParser) cb(key []byte, value []byte, dataType jsonparser.ValueType, offset int) error {
+	switch dataType {
+	case jsonparser.Object: // 嵌套子结构
+		newParser := newJsonStructParser()
+		subObj := newParser.json2Struct(value)
+		hessian2.RegisterPOJOMapping(getJavaClassName(subObj), subObj)
+		jsp.structFields = append(jsp.structFields, reflect.StructField{
+			Name: string(key),
+			Type: reflect.TypeOf(subObj),
+		})
+		jsp.subObjValueMap[string(key)] = reflect.ValueOf(subObj)
+	case jsonparser.Array: //数组结构
+		newParser := newJsonStructParser()
+		subObj := newParser.json2Struct(value)
+		hessian2.RegisterPOJOMapping(getJavaClassName(subObj), subObj) // TODO 目前存在问题
+		jsp.structFields = append(jsp.structFields, reflect.StructField{
+			Name: string(key),
+			Type: reflect.TypeOf(subObj),
+		})
+
+	case jsonparser.String: // 正常结构
+		// "type@value"
+		arr := strings.Split(string(value), "@")
+		var userDefinedType reflect.Type
+		switch arr[0] {
+		case "int":
+			userDefinedType = reflect.TypeOf(0)
+		case "string":
+			userDefinedType = reflect.TypeOf("")
+		case "uint64":
+			userDefinedType = reflect.TypeOf(uint64(0))
+		case "time.Time":
+			userDefinedType = reflect.TypeOf(time.Time{})
+		case "float32":
+			userDefinedType = reflect.TypeOf(float32(0))
+		case "float64":
+			userDefinedType = reflect.TypeOf(float64(0))
+		case "bool":
+			userDefinedType = reflect.TypeOf(false)
+		default:
+			log.Println("warning: val", string(value), " in json is not supported")
+		}
+		if len(arr) > 1 {
+			jsp.valueMap[string(key)] = arr[1]
+		}
+		jsp.structFields = append(jsp.structFields, reflect.StructField{
+			Name: string(key),
+			Type: userDefinedType,
+		})
+	default:
+		log.Println("warning: dataType ", string(value), " in json is not supported")
+	}
+	return nil
+}
+
+func (jsp *jsonStructParser) json2Struct(jsonData []byte) interface{} {
+	if err := jsonparser.ObjectEach(jsonData, jsp.cb); err != nil {
+		log.Println("jsonparser.ObjectEach error = ", err)
+	}
+	typ := reflect.StructOf(jsp.structFields)
+	v := reflect.New(typ).Elem()
+	newty := reflect.TypeOf(v.Addr().Interface()).Elem()
+	for i := 0; i < typ.NumField(); i++ {
+		valStr, ok1 := jsp.valueMap[newty.Field(i).Name]
+		subObj, ok2 := jsp.subObjValueMap[newty.Field(i).Name]
+		if !ok1 && !ok2 {
+			continue
+		}
+
+		if newty.Field(i).Type.Kind() == reflect.Ptr {
+			v.Field(i).Set(subObj)
+			continue
+		}
+		switch newty.Field(i).Type {
+		case reflect.TypeOf(0), reflect.TypeOf(uint64(0)):
+			if parsedInt, err := strconv.Atoi(valStr); err == nil {
+				v.Field(i).SetInt(int64(parsedInt))
+				break
+			}
+			v.Field(i).SetInt(0)
+		case reflect.TypeOf(""):
+			v.Field(i).SetString(valStr)
+		case reflect.TypeOf(time.Time{}):
+			//todo time support v.Field(i).
+		case reflect.TypeOf(float64(0)), reflect.TypeOf(float32(0)):
+			if parsedFloat, err := strconv.ParseFloat(valStr, 64); err == nil {
+				v.Field(i).SetFloat(parsedFloat)
+				break
+			}
+			v.Field(i).SetFloat(0)
+		case reflect.TypeOf(false):
+			if valStr == "true" || valStr == "1" {
+				v.Field(i).SetBool(true)
+			}
+
+		default:
+			log.Println("warning val: ", valStr, " in value is not supported")
+		}
+	}
+	s := v.Addr().Interface()
+	return s
+}
+
+// Jsonfile2Struct read file from @filePath and parse data to interface
+func (jsp *jsonStructParser) Jsonfile2Struct(filePath string) (interface{}, error) {
+	jsonData, err := ioutil.ReadFile(filePath)
+	if err != nil {
+		return nil, err
+	}
+	return jsp.json2Struct(jsonData), nil
+}
+
+// RemoveTargetNameField remove origin interface @v's target field by @targetName
+func (jsp *jsonStructParser) RemoveTargetNameField(v interface{}, targetName string) interface{} {
+	typ := reflect.TypeOf(v).Elem()
+	val := reflect.ValueOf(v).Elem()
+	nums := val.NumField()
+	structFields := make([]reflect.StructField, 0)
+	fieldMap := make(map[string]reflect.Value)
+	for i := 0; i < nums; i++ {
+		if typ.Field(i).Name != targetName {
+			structFields = append(structFields, reflect.StructField{
+				Name: typ.Field(i).Name,
+				Type: typ.Field(i).Type,
+			})
+			fieldMap[typ.Field(i).Name] = val.Field(i)
+		}
+	}
+	newtyp := reflect.StructOf(structFields)
+	newi := reflect.New(newtyp).Elem()
+	newty := reflect.TypeOf(newi.Addr().Interface()).Elem()
+	for i := 0; i < nums-1; i++ {
+		newi.Field(i).Set(fieldMap[newty.Field(i).Name])
+	}
+	return newi.Addr().Interface()
+}
+
+func getJavaClassName(pkg interface{}) string {
+	val := reflect.ValueOf(pkg).Elem()
+	typ := reflect.TypeOf(pkg).Elem()
+	nums := val.NumField()
+	for i := 0; i < nums; i++ {
+		if typ.Field(i).Name == "JavaClassName" {
+			return val.Field(i).String()
+		}
+	}
+	fmt.Println("error: JavaClassName not found")
+	return ""
+}

json-struct-parser/parser_test.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 json_struct_parser
+
+import (
+	"testing"
+)
+
+import (
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_newJsonStructParser(t *testing.T) {
+	path := "./user.json"
+	jparser := newJsonStructParser()
+	_, err := jparser.Jsonfile2Struct(path)
+	assert.Nil(t, err)
+}

json-struct-parser/user.json

+{
+  "ID": "string",
+  "Name": "string",
+  "Age": "int",
+  "JavaClassName":  "string@com.ikurento.user.User",
+  "SubInfo": {
+    "SubID": "string",
+    "SubMale": "bool",
+    "SubAge": "int",
+    "JavaClassName":"string@com.ikurento.user.SubInfo"
+  }
+}
\ No newline at end of file