refactor: restructure API packages into client/http and server/http with typed proxy/visitor models (#5193)

pkg/config/v1/common.go

@@ -16,35 +16,10 @@ package v1
 
 import (
 	"maps"
-	"sync"
 
 	"github.com/fatedier/frp/pkg/util/util"
 )
 
-// TODO(fatedier): Migrate typed config decoding to encoding/json/v2 when it is stable for production use.
-// The current encoding/json(v1) path cannot propagate DisallowUnknownFields into custom UnmarshalJSON
-// methods, so we temporarily keep this global strictness flag protected by a mutex.
-//
-// https://github.com/golang/go/issues/41144
-// https://github.com/golang/go/discussions/63397
-var (
-	DisallowUnknownFields   = false
-	DisallowUnknownFieldsMu sync.Mutex
-)
-
-// WithDisallowUnknownFields temporarily overrides typed config JSON strictness.
-// It restores the previous value before returning.
-func WithDisallowUnknownFields(disallow bool, fn func() error) error {
-	DisallowUnknownFieldsMu.Lock()
-	prev := DisallowUnknownFields
-	DisallowUnknownFields = disallow
-	defer func() {
-		DisallowUnknownFields = prev
-		DisallowUnknownFieldsMu.Unlock()
-	}()
-	return fn()
-}
-
 type AuthScope string
 
 const (

pkg/config/v1/decode.go

@@ -0,0 +1,195 @@
+// Copyright 2026 The frp Authors
+//
+// Licensed 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 v1
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+
+	"github.com/fatedier/frp/pkg/util/jsonx"
+)
+
+type DecodeOptions struct {
+	DisallowUnknownFields bool
+}
+
+func decodeJSONWithOptions(b []byte, out any, options DecodeOptions) error {
+	return jsonx.UnmarshalWithOptions(b, out, jsonx.DecodeOptions{
+		RejectUnknownMembers: options.DisallowUnknownFields,
+	})
+}
+
+func isJSONNull(b []byte) bool {
+	return len(b) == 0 || string(b) == "null"
+}
+
+type typedEnvelope struct {
+	Type   string           `json:"type"`
+	Plugin jsonx.RawMessage `json:"plugin,omitempty"`
+}
+
+func DecodeProxyConfigurerJSON(b []byte, options DecodeOptions) (ProxyConfigurer, error) {
+	if isJSONNull(b) {
+		return nil, errors.New("type is required")
+	}
+
+	var env typedEnvelope
+	if err := jsonx.Unmarshal(b, &env); err != nil {
+		return nil, err
+	}
+
+	configurer := NewProxyConfigurerByType(ProxyType(env.Type))
+	if configurer == nil {
+		return nil, fmt.Errorf("unknown proxy type: %s", env.Type)
+	}
+	if err := decodeJSONWithOptions(b, configurer, options); err != nil {
+		return nil, fmt.Errorf("unmarshal ProxyConfig error: %v", err)
+	}
+
+	if len(env.Plugin) > 0 && !isJSONNull(env.Plugin) {
+		plugin, err := DecodeClientPluginOptionsJSON(env.Plugin, options)
+		if err != nil {
+			return nil, fmt.Errorf("unmarshal proxy plugin error: %v", err)
+		}
+		configurer.GetBaseConfig().Plugin = plugin
+	}
+	return configurer, nil
+}
+
+func DecodeVisitorConfigurerJSON(b []byte, options DecodeOptions) (VisitorConfigurer, error) {
+	if isJSONNull(b) {
+		return nil, errors.New("type is required")
+	}
+
+	var env typedEnvelope
+	if err := jsonx.Unmarshal(b, &env); err != nil {
+		return nil, err
+	}
+
+	configurer := NewVisitorConfigurerByType(VisitorType(env.Type))
+	if configurer == nil {
+		return nil, fmt.Errorf("unknown visitor type: %s", env.Type)
+	}
+	if err := decodeJSONWithOptions(b, configurer, options); err != nil {
+		return nil, fmt.Errorf("unmarshal VisitorConfig error: %v", err)
+	}
+
+	if len(env.Plugin) > 0 && !isJSONNull(env.Plugin) {
+		plugin, err := DecodeVisitorPluginOptionsJSON(env.Plugin, options)
+		if err != nil {
+			return nil, fmt.Errorf("unmarshal visitor plugin error: %v", err)
+		}
+		configurer.GetBaseConfig().Plugin = plugin
+	}
+	return configurer, nil
+}
+
+func DecodeClientPluginOptionsJSON(b []byte, options DecodeOptions) (TypedClientPluginOptions, error) {
+	if isJSONNull(b) {
+		return TypedClientPluginOptions{}, nil
+	}
+
+	var env typedEnvelope
+	if err := jsonx.Unmarshal(b, &env); err != nil {
+		return TypedClientPluginOptions{}, err
+	}
+	if env.Type == "" {
+		return TypedClientPluginOptions{}, errors.New("plugin type is empty")
+	}
+
+	v, ok := clientPluginOptionsTypeMap[env.Type]
+	if !ok {
+		return TypedClientPluginOptions{}, fmt.Errorf("unknown plugin type: %s", env.Type)
+	}
+	optionsStruct := reflect.New(v).Interface().(ClientPluginOptions)
+	if err := decodeJSONWithOptions(b, optionsStruct, options); err != nil {
+		return TypedClientPluginOptions{}, fmt.Errorf("unmarshal ClientPluginOptions error: %v", err)
+	}
+	return TypedClientPluginOptions{
+		Type:                env.Type,
+		ClientPluginOptions: optionsStruct,
+	}, nil
+}
+
+func DecodeVisitorPluginOptionsJSON(b []byte, options DecodeOptions) (TypedVisitorPluginOptions, error) {
+	if isJSONNull(b) {
+		return TypedVisitorPluginOptions{}, nil
+	}
+
+	var env typedEnvelope
+	if err := jsonx.Unmarshal(b, &env); err != nil {
+		return TypedVisitorPluginOptions{}, err
+	}
+	if env.Type == "" {
+		return TypedVisitorPluginOptions{}, errors.New("visitor plugin type is empty")
+	}
+
+	v, ok := visitorPluginOptionsTypeMap[env.Type]
+	if !ok {
+		return TypedVisitorPluginOptions{}, fmt.Errorf("unknown visitor plugin type: %s", env.Type)
+	}
+	optionsStruct := reflect.New(v).Interface().(VisitorPluginOptions)
+	if err := decodeJSONWithOptions(b, optionsStruct, options); err != nil {
+		return TypedVisitorPluginOptions{}, fmt.Errorf("unmarshal VisitorPluginOptions error: %v", err)
+	}
+	return TypedVisitorPluginOptions{
+		Type:                 env.Type,
+		VisitorPluginOptions: optionsStruct,
+	}, nil
+}
+
+func DecodeClientConfigJSON(b []byte, options DecodeOptions) (ClientConfig, error) {
+	type rawClientConfig struct {
+		ClientCommonConfig
+		Proxies  []jsonx.RawMessage `json:"proxies,omitempty"`
+		Visitors []jsonx.RawMessage `json:"visitors,omitempty"`
+	}
+
+	raw := rawClientConfig{}
+	if err := decodeJSONWithOptions(b, &raw, options); err != nil {
+		return ClientConfig{}, err
+	}
+
+	cfg := ClientConfig{
+		ClientCommonConfig: raw.ClientCommonConfig,
+		Proxies:            make([]TypedProxyConfig, 0, len(raw.Proxies)),
+		Visitors:           make([]TypedVisitorConfig, 0, len(raw.Visitors)),
+	}
+
+	for i, proxyData := range raw.Proxies {
+		proxyCfg, err := DecodeProxyConfigurerJSON(proxyData, options)
+		if err != nil {
+			return ClientConfig{}, fmt.Errorf("decode proxy at index %d: %w", i, err)
+		}
+		cfg.Proxies = append(cfg.Proxies, TypedProxyConfig{
+			Type:            proxyCfg.GetBaseConfig().Type,
+			ProxyConfigurer: proxyCfg,
+		})
+	}
+
+	for i, visitorData := range raw.Visitors {
+		visitorCfg, err := DecodeVisitorConfigurerJSON(visitorData, options)
+		if err != nil {
+			return ClientConfig{}, fmt.Errorf("decode visitor at index %d: %w", i, err)
+		}
+		cfg.Visitors = append(cfg.Visitors, TypedVisitorConfig{
+			Type:              visitorCfg.GetBaseConfig().Type,
+			VisitorConfigurer: visitorCfg,
+		})
+	}
+
+	return cfg, nil
+}

pkg/config/v1/decode_test.go

@@ -0,0 +1,86 @@
+// Copyright 2026 The frp Authors
+//
+// Licensed 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 v1
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestDecodeProxyConfigurerJSON_StrictPluginUnknownFields(t *testing.T) {
+	require := require.New(t)
+
+	data := []byte(`{
+		"name":"p1",
+		"type":"tcp",
+		"localPort":10080,
+		"plugin":{
+			"type":"http2https",
+			"localAddr":"127.0.0.1:8080",
+			"unknownInPlugin":"value"
+		}
+	}`)
+
+	_, err := DecodeProxyConfigurerJSON(data, DecodeOptions{DisallowUnknownFields: false})
+	require.NoError(err)
+
+	_, err = DecodeProxyConfigurerJSON(data, DecodeOptions{DisallowUnknownFields: true})
+	require.ErrorContains(err, "unknownInPlugin")
+}
+
+func TestDecodeVisitorConfigurerJSON_StrictPluginUnknownFields(t *testing.T) {
+	require := require.New(t)
+
+	data := []byte(`{
+		"name":"v1",
+		"type":"stcp",
+		"serverName":"server",
+		"bindPort":10081,
+		"plugin":{
+			"type":"virtual_net",
+			"destinationIP":"10.0.0.1",
+			"unknownInPlugin":"value"
+		}
+	}`)
+
+	_, err := DecodeVisitorConfigurerJSON(data, DecodeOptions{DisallowUnknownFields: false})
+	require.NoError(err)
+
+	_, err = DecodeVisitorConfigurerJSON(data, DecodeOptions{DisallowUnknownFields: true})
+	require.ErrorContains(err, "unknownInPlugin")
+}
+
+func TestDecodeClientConfigJSON_StrictUnknownProxyField(t *testing.T) {
+	require := require.New(t)
+
+	data := []byte(`{
+		"serverPort":7000,
+		"proxies":[
+			{
+				"name":"p1",
+				"type":"tcp",
+				"localPort":10080,
+				"unknownField":"value"
+			}
+		]
+	}`)
+
+	_, err := DecodeClientConfigJSON(data, DecodeOptions{DisallowUnknownFields: false})
+	require.NoError(err)
+
+	_, err = DecodeClientConfigJSON(data, DecodeOptions{DisallowUnknownFields: true})
+	require.ErrorContains(err, "unknownField")
+}

pkg/config/v1/proxy.go

@@ -15,16 +15,13 @@
 package v1
 
 import (
-	"bytes"
-	"encoding/json"
-	"errors"
-	"fmt"
 	"maps"
 	"reflect"
 	"slices"
 
 	"github.com/fatedier/frp/pkg/config/types"
 	"github.com/fatedier/frp/pkg/msg"
+	"github.com/fatedier/frp/pkg/util/jsonx"
 	"github.com/fatedier/frp/pkg/util/util"
 )
 
@@ -202,35 +199,18 @@ type TypedProxyConfig struct {
 }
 
 func (c *TypedProxyConfig) UnmarshalJSON(b []byte) error {
-	if len(b) == 4 && string(b) == "null" {
-		return errors.New("type is required")
-	}
-
-	typeStruct := struct {
-		Type string `json:"type"`
-	}{}
-	if err := json.Unmarshal(b, &typeStruct); err != nil {
+	configurer, err := DecodeProxyConfigurerJSON(b, DecodeOptions{})
+	if err != nil {
 		return err
 	}
 
-	c.Type = typeStruct.Type
-	configurer := NewProxyConfigurerByType(ProxyType(typeStruct.Type))
-	if configurer == nil {
-		return fmt.Errorf("unknown proxy type: %s", typeStruct.Type)
-	}
-	decoder := json.NewDecoder(bytes.NewBuffer(b))
-	if DisallowUnknownFields {
-		decoder.DisallowUnknownFields()
-	}
-	if err := decoder.Decode(configurer); err != nil {
-		return fmt.Errorf("unmarshal ProxyConfig error: %v", err)
-	}
+	c.Type = configurer.GetBaseConfig().Type
 	c.ProxyConfigurer = configurer
 	return nil
 }
 
 func (c *TypedProxyConfig) MarshalJSON() ([]byte, error) {
-	return json.Marshal(c.ProxyConfigurer)
+	return jsonx.Marshal(c.ProxyConfigurer)
 }
 
 type ProxyConfigurer interface {

pkg/config/v1/proxy_plugin.go

@@ -15,14 +15,11 @@
 package v1
 
 import (
-	"bytes"
-	"encoding/json"
-	"errors"
-	"fmt"
 	"reflect"
 
 	"github.com/samber/lo"
 
+	"github.com/fatedier/frp/pkg/util/jsonx"
 	"github.com/fatedier/frp/pkg/util/util"
 )
 
@@ -71,42 +68,16 @@ func (c TypedClientPluginOptions) Clone() TypedClientPluginOptions {
 }
 
 func (c *TypedClientPluginOptions) UnmarshalJSON(b []byte) error {
-	if len(b) == 4 && string(b) == "null" {
-		return nil
-	}
-
-	typeStruct := struct {
-		Type string `json:"type"`
-	}{}
-	if err := json.Unmarshal(b, &typeStruct); err != nil {
+	decoded, err := DecodeClientPluginOptionsJSON(b, DecodeOptions{})
+	if err != nil {
 		return err
 	}
-
-	c.Type = typeStruct.Type
-	if c.Type == "" {
-		return errors.New("plugin type is empty")
-	}
-
-	v, ok := clientPluginOptionsTypeMap[typeStruct.Type]
-	if !ok {
-		return fmt.Errorf("unknown plugin type: %s", typeStruct.Type)
-	}
-	options := reflect.New(v).Interface().(ClientPluginOptions)
-
-	decoder := json.NewDecoder(bytes.NewBuffer(b))
-	if DisallowUnknownFields {
-		decoder.DisallowUnknownFields()
-	}
-
-	if err := decoder.Decode(options); err != nil {
-		return fmt.Errorf("unmarshal ClientPluginOptions error: %v", err)
-	}
-	c.ClientPluginOptions = options
+	*c = decoded
 	return nil
 }
 
 func (c *TypedClientPluginOptions) MarshalJSON() ([]byte, error) {
-	return json.Marshal(c.ClientPluginOptions)
+	return jsonx.Marshal(c.ClientPluginOptions)
 }
 
 type HTTP2HTTPSPluginOptions struct {

pkg/config/v1/visitor.go

@@ -15,12 +15,9 @@
 package v1
 
 import (
-	"bytes"
-	"encoding/json"
-	"errors"
-	"fmt"
 	"reflect"
 
+	"github.com/fatedier/frp/pkg/util/jsonx"
 	"github.com/fatedier/frp/pkg/util/util"
 )
 
@@ -93,35 +90,18 @@ type TypedVisitorConfig struct {
 }
 
 func (c *TypedVisitorConfig) UnmarshalJSON(b []byte) error {
-	if len(b) == 4 && string(b) == "null" {
-		return errors.New("type is required")
-	}
-
-	typeStruct := struct {
-		Type string `json:"type"`
-	}{}
-	if err := json.Unmarshal(b, &typeStruct); err != nil {
+	configurer, err := DecodeVisitorConfigurerJSON(b, DecodeOptions{})
+	if err != nil {
 		return err
 	}
 
-	c.Type = typeStruct.Type
-	configurer := NewVisitorConfigurerByType(VisitorType(typeStruct.Type))
-	if configurer == nil {
-		return fmt.Errorf("unknown visitor type: %s", typeStruct.Type)
-	}
-	decoder := json.NewDecoder(bytes.NewBuffer(b))
-	if DisallowUnknownFields {
-		decoder.DisallowUnknownFields()
-	}
-	if err := decoder.Decode(configurer); err != nil {
-		return fmt.Errorf("unmarshal VisitorConfig error: %v", err)
-	}
+	c.Type = configurer.GetBaseConfig().Type
 	c.VisitorConfigurer = configurer
 	return nil
 }
 
 func (c *TypedVisitorConfig) MarshalJSON() ([]byte, error) {
-	return json.Marshal(c.VisitorConfigurer)
+	return jsonx.Marshal(c.VisitorConfigurer)
 }
 
 func NewVisitorConfigurerByType(t VisitorType) VisitorConfigurer {

pkg/config/v1/visitor_plugin.go

@@ -15,11 +15,9 @@
 package v1
 
 import (
-	"bytes"
-	"encoding/json"
-	"errors"
-	"fmt"
 	"reflect"
+
+	"github.com/fatedier/frp/pkg/util/jsonx"
 )
 
 const (
@@ -49,42 +47,16 @@ func (c TypedVisitorPluginOptions) Clone() TypedVisitorPluginOptions {
 }
 
 func (c *TypedVisitorPluginOptions) UnmarshalJSON(b []byte) error {
-	if len(b) == 4 && string(b) == "null" {
-		return nil
-	}
-
-	typeStruct := struct {
-		Type string `json:"type"`
-	}{}
-	if err := json.Unmarshal(b, &typeStruct); err != nil {
+	decoded, err := DecodeVisitorPluginOptionsJSON(b, DecodeOptions{})
+	if err != nil {
 		return err
 	}
-
-	c.Type = typeStruct.Type
-	if c.Type == "" {
-		return errors.New("visitor plugin type is empty")
-	}
-
-	v, ok := visitorPluginOptionsTypeMap[typeStruct.Type]
-	if !ok {
-		return fmt.Errorf("unknown visitor plugin type: %s", typeStruct.Type)
-	}
-	options := reflect.New(v).Interface().(VisitorPluginOptions)
-
-	decoder := json.NewDecoder(bytes.NewBuffer(b))
-	if DisallowUnknownFields {
-		decoder.DisallowUnknownFields()
-	}
-
-	if err := decoder.Decode(options); err != nil {
-		return fmt.Errorf("unmarshal VisitorPluginOptions error: %v", err)
-	}
-	c.VisitorPluginOptions = options
+	*c = decoded
 	return nil
 }
 
 func (c *TypedVisitorPluginOptions) MarshalJSON() ([]byte, error) {
-	return json.Marshal(c.VisitorPluginOptions)
+	return jsonx.Marshal(c.VisitorPluginOptions)
 }
 
 type VirtualNetVisitorPluginOptions struct {