diff --git a/.pylintrc b/.pylintrc
index c900bb48..7f97f88a 100644
--- a/.pylintrc
+++ b/.pylintrc
@@ -66,6 +66,7 @@ disable=
     missing-docstring,
     unused-argument,
     no-self-use,
+    no-member,  # dataclass is not well supported by pylint
 
 
 # Enable the message, report, category or checker with the given id(s). You can
@@ -159,7 +160,7 @@ class-naming-style=PascalCase
 
 # Regular expression matching correct constant names. Overrides const-naming-
 # style.
-const-rgx=^([A-Z][A-Z0-9_]+|[a-z][a-z0-9_]+|__\w+__)$
+const-rgx=^_?([A-Z][A-Z0-9_]+|[a-z][a-z0-9_]+|__\w+__)$
 
 
 # Minimum line length for functions/classes that require docstrings, shorter
diff --git a/.travis.yml b/.travis.yml
index 091f336d..5fd6f616 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,6 +7,5 @@ install:
   - pip install -r requirements-dev.txt
 # command to run tests
 script:
-  - python tools/ci/check_format.py
-  - pylint --rcfile=.pylintrc vnpy
+  - python tools/ci/check_all.py
   - python tests/test_all.py
diff --git a/README.md b/README.md
index 73b6e205..98a15033 100644
--- a/README.md
+++ b/README.md
@@ -9,8 +9,9 @@ vnpy 2.0
 
 在提交代码的时候，请遵守以下规则，以提高代码质量：
 
-  * 使用[yapf]（目前必须使用github上的最新代码：```pip install https://github.com/google/yapf/archive/master.zip```）格式化你的代码。对你的每一个文件运行```yapf -i --style .style.yapf <file>```即可。
-  * 使用[pylint]检查你的代码，确保没有error和warning。我们使用的pylint规则在项目根目录下。运行```pylint --rcfile=.pylintrc vnpy```即可。
+  * 使用[black]格式化你的代码。运行```black .```即可。
+  * 使用[pylint]检查你的代码(主要检查命名规则)，确保没有error和warning。在项目根目录下运行```pylint vnpy```即可。
+  * 使用[flake8]检查你的代码，确保没有error和warning。在项目根目录下运行```flake8```即可。
   
   [yapf]:https://github.com/google/yapf
   [pylint]:https://github.com/PyCQA/pylint
diff --git a/binding/__init__.py b/binding/__init__.py
new file mode 100644
index 00000000..838c2d2c
--- /dev/null
+++ b/binding/__init__.py
@@ -0,0 +1 @@
+# this file is created only for making pylint work
diff --git a/binding/generator/__init__.py b/binding/generator/__init__.py
new file mode 100644
index 00000000..838c2d2c
--- /dev/null
+++ b/binding/generator/__init__.py
@@ -0,0 +1 @@
+# this file is created only for making pylint work
diff --git a/binding/generator/autocxxpy/__init__.py b/binding/generator/autocxxpy/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/binding/generator/autocxxpy/preprocessor.py b/binding/generator/autocxxpy/preprocessor.py
index 4fcca56c..2c8dee90 100644
--- a/binding/generator/autocxxpy/preprocessor.py
+++ b/binding/generator/autocxxpy/preprocessor.py
@@ -4,7 +4,6 @@ import ast
 import re
 from collections import defaultdict
 from dataclasses import dataclass, field
-from enum import Enum
 from typing import Dict, List, Optional, Set
 
 from .cxxparser import (
@@ -18,12 +17,6 @@ from .cxxparser import (
 from .type import array_base, base_types, is_array_type
 
 
-class CallbackType(Enum):
-    NotCallback = 0  # not a callback
-    Direct = 1
-    Async = 2
-
-
 """
 42          - dec
 0b101010    - bin
diff --git a/binding/generator/autocxxpy/type.py b/binding/generator/autocxxpy/type.py
index eb57d84d..a09f2636 100644
--- a/binding/generator/autocxxpy/type.py
+++ b/binding/generator/autocxxpy/type.py
@@ -35,11 +35,11 @@ def is_pointer_type(t: str):
     return "*" in t
 
 
-_remove_pointer_re = re.compile("[ \t]*\\*[ \t]*")
+_REMOVE_POINTER_RE = re.compile("[ \t]*\\*[ \t]*")
 
 
 def pointer_base(t: str):
-    return _remove_pointer_re.sub("", t)
+    return _REMOVE_POINTER_RE.sub("", t)
 
 
 def is_reference_type(t: str):
diff --git a/binding/tests/__init__.py b/binding/tests/__init__.py
new file mode 100644
index 00000000..838c2d2c
--- /dev/null
+++ b/binding/tests/__init__.py
@@ -0,0 +1 @@
+# this file is created only for making pylint work
diff --git a/binding/tests/test.py b/binding/tests/test.py
index 65eead86..bb3ff46d 100644
--- a/binding/tests/test.py
+++ b/binding/tests/test.py
@@ -26,6 +26,7 @@ api = CThostFtdcTraderApi.CreateFtdcTraderApi("flow2")
 print("creating ctp spi")
 
 
+# pylint: disable=invalid-name
 class Spi(CThostFtdcTraderSpi):
     def OnFrontConnected(self) -> None:
         print("OnFrontConnected!")
@@ -64,6 +65,7 @@ class Spi(CThostFtdcTraderSpi):
         self, pRspInfo: CThostFtdcRspInfoField, nRequestID: int, bIsLast: bool
     ) -> None:
         print("OnRspError!")
+# pylint: enable=invalid-name
 
 
 spi = Spi()
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 00000000..838c2d2c
--- /dev/null
+++ b/tests/__init__.py
@@ -0,0 +1 @@
+# this file is created only for making pylint work
diff --git a/tests/trader/__init__.py b/tests/trader/__init__.py
new file mode 100644
index 00000000..838c2d2c
--- /dev/null
+++ b/tests/trader/__init__.py
@@ -0,0 +1 @@
+# this file is created only for making pylint work
diff --git a/tools/check/check_linter.py b/tools/check/check_linter.py
index d4dbc7a4..3f59a3a7 100644
--- a/tools/check/check_linter.py
+++ b/tools/check/check_linter.py
@@ -18,7 +18,7 @@ def check_flake8():
 def check_pylint():
     passed = True
     try:
-        subprocess.check_call(["pylint", "vnpy", "-j", "0"])
+        subprocess.check_call(["pylint", "-j", "0", "vnpy", "binding", "tests"])
     except subprocess.SubprocessError:
         passed = False
     return passed
diff --git a/tools/check/utils.py b/tools/check/utils.py
index 02548a3c..52152c6c 100644
--- a/tools/check/utils.py
+++ b/tools/check/utils.py
@@ -1,4 +1,5 @@
 import logging
+import os
 from typing import Callable
 
 logger = logging.getLogger(__file__)
@@ -9,7 +10,10 @@ def check_and_warning(*args, fast_fail: bool = False):
     for i in args:
         if isinstance(i, Callable):
             print(f"check using {i}")
-            if not i():
+            cwd = os.getcwd()
+            res = i()
+            os.chdir(cwd)
+            if not res:
                 passed = False
                 logger.warning("check of %s failed!", i)
             if not passed and fast_fail:
diff --git a/vnpy/app/cta_strategy/template.py b/vnpy/app/cta_strategy/template.py
index 3dc3624d..1f4e328f 100644
--- a/vnpy/app/cta_strategy/template.py
+++ b/vnpy/app/cta_strategy/template.py
@@ -192,10 +192,7 @@ class CtaTemplate(ABC):
         return self.cta_engine.get_engine_type()
 
     def load_bar(
-        self,
-        days: int,
-        interval: Interval = Interval.MINUTE,
-        callback=None,
+        self, days: int, interval: Interval = Interval.MINUTE, callback=None
     ):
         """
         Load historical bar data for initializing strategy.