Add an abstract json layout to make it's easier to change json library (#16528)

* Add an abstract json layout to make it's easier to change json library

* Fix import

* Fix import sequence

* Fix blank lines

* Fix blank lines

1 files changed, 142 insertions, 0 deletions

diff --git a/modules/json/json.go b/modules/json/json.go
new file mode 100644
index 0000000000..be42b6ae6c
--- /dev/null
+++ b/modules/json/json.go
@@ -0,0 +1,142 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package json
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+
+	jsoniter "github.com/json-iterator/go"
+)
+
+// Encoder represents an encoder for json
+type Encoder interface {
+	Encode(v interface{}) error
+}
+
+// Decoder represents a decoder for json
+type Decoder interface {
+	Decode(v interface{}) error
+}
+
+// Interface represents an interface to handle json data
+type Interface interface {
+	Marshal(v interface{}) ([]byte, error)
+	Unmarshal(data []byte, v interface{}) error
+	NewEncoder(writer io.Writer) Encoder
+	NewDecoder(reader io.Reader) Decoder
+	Indent(dst *bytes.Buffer, src []byte, prefix, indent string) error
+}
+
+var (
+	// DefaultJSONHandler default json handler
+	DefaultJSONHandler Interface = JSONiter{jsoniter.ConfigCompatibleWithStandardLibrary}
+
+	_ Interface = StdJSON{}
+	_ Interface = JSONiter{}
+)
+
+// StdJSON implements Interface via encoding/json
+type StdJSON struct{}
+
+// Marshal implements Interface
+func (StdJSON) Marshal(v interface{}) ([]byte, error) {
+	return json.Marshal(v)
+}
+
+// Unmarshal implements Interface
+func (StdJSON) Unmarshal(data []byte, v interface{}) error {
+	return json.Unmarshal(data, v)
+}
+
+// NewEncoder implements Interface
+func (StdJSON) NewEncoder(writer io.Writer) Encoder {
+	return json.NewEncoder(writer)
+}
+
+// NewDecoder implements Interface
+func (StdJSON) NewDecoder(reader io.Reader) Decoder {
+	return json.NewDecoder(reader)
+}
+
+// Indent implements Interface
+func (StdJSON) Indent(dst *bytes.Buffer, src []byte, prefix, indent string) error {
+	return json.Indent(dst, src, prefix, indent)
+}
+
+// JSONiter implements Interface via jsoniter
+type JSONiter struct {
+	jsoniter.API
+}
+
+// Marshal implements Interface
+func (j JSONiter) Marshal(v interface{}) ([]byte, error) {
+	return j.API.Marshal(v)
+}
+
+// Unmarshal implements Interface
+func (j JSONiter) Unmarshal(data []byte, v interface{}) error {
+	return j.API.Unmarshal(data, v)
+}
+
+// NewEncoder implements Interface
+func (j JSONiter) NewEncoder(writer io.Writer) Encoder {
+	return j.API.NewEncoder(writer)
+}
+
+// NewDecoder implements Interface
+func (j JSONiter) NewDecoder(reader io.Reader) Decoder {
+	return j.API.NewDecoder(reader)
+}
+
+// Indent implements Interface, since jsoniter don't support Indent, just use encoding/json's
+func (j JSONiter) Indent(dst *bytes.Buffer, src []byte, prefix, indent string) error {
+	return json.Indent(dst, src, prefix, indent)
+}
+
+// Marshal converts object as bytes
+func Marshal(v interface{}) ([]byte, error) {
+	return DefaultJSONHandler.Marshal(v)
+}
+
+// Unmarshal decodes object from bytes
+func Unmarshal(data []byte, v interface{}) error {
+	return DefaultJSONHandler.Unmarshal(data, v)
+}
+
+// NewEncoder creates an encoder to write objects to writer
+func NewEncoder(writer io.Writer) Encoder {
+	return DefaultJSONHandler.NewEncoder(writer)
+}
+
+// NewDecoder creates a decoder to read objects from reader
+func NewDecoder(reader io.Reader) Decoder {
+	return DefaultJSONHandler.NewDecoder(reader)
+}
+
+// Indent appends to dst an indented form of the JSON-encoded src.
+func Indent(dst *bytes.Buffer, src []byte, prefix, indent string) error {
+	return DefaultJSONHandler.Indent(dst, src, prefix, indent)
+}
+
+// MarshalIndent copied from encoding/json
+func MarshalIndent(v interface{}, prefix, indent string) ([]byte, error) {
+	b, err := Marshal(v)
+	if err != nil {
+		return nil, err
+	}
+	var buf bytes.Buffer
+	err = Indent(&buf, b, prefix, indent)
+	if err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+
+// Valid proxy to json.Valid
+func Valid(data []byte) bool {
+	return json.Valid(data)
+}