chore: update readme, update action script

.github/workflows/go.yml

@@ -26,7 +26,6 @@ jobs:
 
     - name: Revive check
       uses: morphy2k/revive-action@v2.3.1
-      if: ${{ matrix.os == 'ubuntu-latest' }}
       with:
         # Exclude patterns, separated by semicolons (optional)
         exclude: "./internal/..."

README.md

@@ -283,10 +283,10 @@ ioutil.WriteFile("my-config.json", buf.Bytes(), 0755)
 
 **Pretty dump JSON**
 
+You can set the default var `JSONMarshalIndent` or custom a new JSON driver. 
+
 ```go
-config.SetEncoder(config.JSON, func(v interface{}) ([]byte, error) {
-    return json.MarshalIndent(v, "", "    ")
-})
+config.JSONMarshalIndent = "    "
 ```
 
 ## Available options

README.zh-CN.md

@@ -265,10 +265,10 @@ ioutil.WriteFile("my-config.json", buf.Bytes(), 0755)
 
 **示例:美化导出的JSON**
 
+可以设置默认变量 `JSONMarshalIndent` 的值 或 自定义新的 JSON 驱动程序。
+
 ```go
-config.SetEncoder(config.JSON, func(v interface{}) ([]byte, error) {
-    return json.MarshalIndent(v, "", "    ")
-})
+config.JSONMarshalIndent = "    "
 ```
 
 ## 可用选项

write.go

@@ -10,8 +10,8 @@ import (
 )
 
 var (
-	readonlyErr   = errors.New("the config instance in 'readonly' mode")
-	keyIsEmptyErr = errors.New("the config key is cannot be empty")
+	errReadonly   = errors.New("the config instance in 'readonly' mode")
+	errKeyIsEmpty = errors.New("the config key is cannot be empty")
 )
 
 // SetData for override the Config.Data
@@ -36,15 +36,15 @@ func Set(key string, val interface{}, setByPath ...bool) error {
 // Set a value by key string.
 func (c *Config) Set(key string, val interface{}, setByPath ...bool) (err error) {
 	if c.opts.Readonly {
-		return readonlyErr
+		return errReadonly
 	}
 
 	c.lock.Lock()
 	defer c.lock.Unlock()
 
 	sep := c.opts.Delimiter
 	if key = formatKey(key, string(sep)); key == "" {
-		return keyIsEmptyErr
+		return errKeyIsEmpty
 	}
 
 	defer c.fireHook(OnSetValue)