feat: accept camelcase for config keys (#2651)

* feat: accept camelcase for config keys

* chore: refactor

* chore: refactor

* chore: add more tests

* chore: refactor

* fix: map elements of array

internal/encoding/encoding.go

@@ -0,0 +1,75 @@
+package encoding
+
+import (
+	"bytes"
+	"encoding/json"
+
+	"github.com/pelletier/go-toml/v2"
+	"github.com/zeromicro/go-zero/core/lang"
+	"gopkg.in/yaml.v2"
+)
+
+func TomlToJson(data []byte) ([]byte, error) {
+	var val interface{}
+	if err := toml.NewDecoder(bytes.NewReader(data)).Decode(&val); err != nil {
+		return nil, err
+	}
+
+	var buf bytes.Buffer
+	if err := json.NewEncoder(&buf).Encode(val); err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}
+
+func YamlToJson(data []byte) ([]byte, error) {
+	var val interface{}
+	if err := yaml.Unmarshal(data, &val); err != nil {
+		return nil, err
+	}
+
+	val = toStringKeyMap(val)
+
+	var buf bytes.Buffer
+	if err := json.NewEncoder(&buf).Encode(val); err != nil {
+		return nil, err
+	}
+
+	return buf.Bytes(), nil
+}
+
+func convertKeyToString(in map[interface{}]interface{}) map[string]interface{} {
+	res := make(map[string]interface{})
+	for k, v := range in {
+		res[lang.Repr(k)] = toStringKeyMap(v)
+	}
+	return res
+}
+
+func convertNumberToJsonNumber(in interface{}) json.Number {
+	return json.Number(lang.Repr(in))
+}
+
+func convertSlice(in []interface{}) []interface{} {
+	res := make([]interface{}, len(in))
+	for i, v := range in {
+		res[i] = toStringKeyMap(v)
+	}
+	return res
+}
+
+func toStringKeyMap(v interface{}) interface{} {
+	switch v := v.(type) {
+	case []interface{}:
+		return convertSlice(v)
+	case map[interface{}]interface{}:
+		return convertKeyToString(v)
+	case bool, string:
+		return v
+	case int, uint, int8, uint8, int16, uint16, int32, uint32, int64, uint64, float32, float64:
+		return convertNumberToJsonNumber(v)
+	default:
+		return lang.Repr(v)
+	}
+}