diff --git a/Basis/Filter.py b/Basis/Filter.py
index 7384495..76bdf7d 100644
--- a/Basis/Filter.py
+++ b/Basis/Filter.py
@@ -1,85 +1,120 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
+import copy
+
 filterObject = {
     'optional': {
+        'type': bool,
         'optional': True,  # `optional` is not force require
         'default': False,  # disable `optional` option in default
         'allowNone': False,  # `optional` couldn't be None
-        'type': bool,
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `optional` key'
     },
     'default': {
+        'type': any,  # skip type check
         'optional': True,  # `default` is not force require
         'default': None,
         'allowNone': True,  # `default` can be None
-        'type': any,  # skip type check
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `default` key'
     },
     'allowNone': {
+        'type': bool,
         'optional': True,  # `allowNone` is not force require
         'default': False,  # disable `allowNone` option in default
         'allowNone': False,  # `allowNone` couldn't be None
-        'type': bool,
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `allowNone` key'
     },
     'type': {
+        'type': [any, type, list, dict],
         'optional': False,  # `type` is force require
         'allowNone': False,  # `type` couldn't be None
-        'type': [any, type, list, dict],
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `type` key'
     },
     'multiSub': {
+        'type': bool,
         'optional': True,  # `multiSub` is not force require
         'default': False,  # disable `multiSub` option in default
         'allowNone': False,  # `multiSub` couldn't be None
-        'type': bool,
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `multiSub` key'
     },
     'indexKey': {
+        'type': str,
         'optional': True,  # `indexKey` is not force require
         'default': 'type',
         'allowNone': False,  # `indexKey` couldn't be None
-        'type': str,
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `indexKey` key'
     },
     'format': {
+        'type': any,
         'optional': True,  # `format` is not force require
         'default': lambda x: x,  # don't change anything
         'allowNone': False,  # `format` couldn't be None
-        'type': any,
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `format` key'
     },
     'filter': {
+        'type': any,
         'optional': True,  # `filter` is not force require
         'default': lambda x: True,  # always pass filter
         'allowNone': False,  # `filter` couldn't be None
-        'type': any,
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `filter` key'
     },
     'errMsg': {
+        'type': str,
         'optional': True,  # `errMsg` is not force require
         'default': 'filter error',
         'allowNone': False,  # `errMsg` couldn't be None
-        'type': str,
-        'format': lambda x: x,  # return same value
-        'filter': lambda b: True,  # always return True
-        'errMsg': 'Invalid `errMsg` key'
-    },
+    }
 }
+
+for field in filterObject:
+    filterObject[field]['errMsg'] = 'Invalid `%s` key' % field
+    filterObject[field]['format'] = filterObject['format']['default']  # return same value
+    filterObject[field]['filter'] = filterObject['filter']['default']  # always return True
+
+
+def Filter(raw: dict, rules: dict) -> dict:
+    if type(raw) != dict:
+        raise RuntimeError('Invalid input for filter')
+    data = {}
+    raw = copy.deepcopy(raw)
+    rules = copy.deepcopy(rules)
+    for key, rule in rules.items():
+        # pretreatment process (raw --[copy / default value]--> data)
+        if key not in raw:  # key not exist
+            if not rule['optional']:  # force require key not exist
+                raise RuntimeError('Miss `%s` field' % key)
+            data[key] = rule['default']  # set default value
+        else:  # key exist
+            data[key] = raw[key]
+        # format process (data --[format]--> data)
+        try:
+            data[key] = rule['format'](data[key])  # run format
+        except:
+            raise RuntimeError(rule['errMsg'])  # format error
+        if data[key] is None:  # key content is None
+            if not rule['allowNone']:  # key is not allow None
+                raise RuntimeError('Field `%s` shouldn\'t be None' % key)
+            continue  # skip following process
+        # filter process (data --[type check (& filter check)]--> pass / non-pass)
+        if type(rule['type']) == type:  # str / int / bool / ...
+            rule['type'] = [rule['type']]  # str -> [str] / int -> [int] / ...
+        if type(rule['type']) == list:  # [str, int, bool, ...]
+            if data[key] == any and any in rule['type']:  # special case -> skip type filter
+                pass
+            elif type(data[key]) not in rule['type']:  # type not in allow list
+                raise RuntimeError('Invalid `%s` field' % key)
+        elif type(rule['type']) == dict:  # check subObject
+            if not rule['multiSub']:  # single subObject
+                data[key] = Filter(data[key], rule['type'])
+            else:  # multi subObject
+                # TODO: multi sub filter
+                pass
+            continue
+        elif rule['type'] != any:  # type == any -> skip type filter
+            raise RuntimeError('Unknown `type` in rules')
+        if not rule['filter'](data[key]):  # run filter
+            raise RuntimeError(rule['errMsg'])
+    return data
+
+
+def rulesFilter(rules: dict) -> dict:
+    result = {}
+    for key, rule in rules.items():  # filter by basic rules
+        result[key] = Filter(rule, filterObject)
+    return result
+
+
+filterObject = rulesFilter(filterObject)  # format itself
diff --git a/Filter/Shadowsocks.py b/Filter/Shadowsocks.py
index 9702174..0f038ec 100644
--- a/Filter/Shadowsocks.py
+++ b/Filter/Shadowsocks.py
@@ -4,9 +4,10 @@
 from Filter.Plugin import pluginFormat
 from Basis.Functions import toInt, toStr
 from Basis.Functions import isHost, isPort
+from Basis.Filter import Filter, rulesFilter
 from Basis.Constant import ssMethods, pluginClients
 
-pluginObject = {
+pluginObject = rulesFilter({
     'type': {
         'type': str,
         'format': lambda s: pluginFormat(toStr(s).strip().lower()),
@@ -20,9 +21,9 @@ pluginObject = {
         'format': toStr,
         'errMsg': 'Invalid SIP003 param'
     }
-}
+})
 
-ssObject = {
+ssObject = rulesFilter({
     'server': {
         'type': str,
         'format': toStr,
@@ -53,4 +54,7 @@ ssObject = {
         'type': pluginObject,
         'errMsg': 'Invalid pluginObject'
     }
-}
+})
+
+from pprint import pprint
+pprint(ssObject, sort_dicts = False)
diff --git a/demo.py b/demo.py
new file mode 100755
index 0000000..7be03fd
--- /dev/null
+++ b/demo.py
@@ -0,0 +1,7 @@
+#!/usr/bin/env python
+
+import Filter.Shadowsocks
+
+# from pprint import pprint
+# from Basis.Filter import filterObject
+# pprint(filterObject, sort_dicts = False)