diff --git a/docs/api.rst b/docs/api.rst
index 0f88467..b965b14 100644
--- a/docs/api.rst
+++ b/docs/api.rst
@@ -23,11 +23,19 @@ db
 .. automodule:: hobbit_core.flask_hobbit.db
    :members:
    :undoc-members:
-   :exclude-members: SurrogatePK
+   :exclude-members: SurrogatePK, EnumExt
 
    .. autoclass:: SurrogatePK
        :members: __repr__
 
+   .. autoclass:: EnumExt
+       :members:
+
+       .. automethod:: strict_dump
+       .. automethod:: dump
+       .. automethod:: load
+       .. automethod:: to_opts
+
 pagination
 ^^^^^^^^^^
 
diff --git a/hobbit_core/flask_hobbit/db.py b/hobbit_core/flask_hobbit/db.py
index 3063f7f..0c87094 100644
--- a/hobbit_core/flask_hobbit/db.py
+++ b/hobbit_core/flask_hobbit/db.py
@@ -1,5 +1,6 @@
 # -*- encoding: utf-8 -*-
 import enum
+import six
 
 from sqlalchemy import Integer, Column, ForeignKey, func, DateTime
 
@@ -61,29 +62,90 @@ def reference_col(tablename, nullable=False, pk_name='id', **kwargs):
 
 
 class EnumExt(enum.Enum):
-    """ serialize/deserialize sqlalchemy enum field
+    """ Extension for serialize/deserialize sqlalchemy enum field.
+
+    Be sure ``type(key)`` is ``int`` and ``type(value)`` is ``str``
+    (``label = (key, value)``).
+
+    Examples::
+
+        class TaskState(EnumExt):
+            # label = (key, value)
+            CREATED = (0, '新建')
+            PENDING = (1, '等待')
+            STARTING = (2, '开始')
+            RUNNING = (3, '运行中')
+            FINISHED = (4, '已完成')
+            FAILED = (5, '失败')
     """
+
     @classmethod
-    def strict_dump(cls, key, verbose=False):
-        pos = 1 if verbose else 0
-        return cls[key].value[pos]
+    def strict_dump(cls, label, verbose=False):
+        """Get key or value by label.
+
+        Examples::
+
+            TaskState.strict_dump('CREATED')  # 0
+            TaskState.strict_dump('CREATED', verbose=True)  # '新建'
+
+        Returns:
+            int|str: Key or value, If label not exist, raise ``KeyError``.
+        """
+
+        return cls[label].value[1 if verbose else 0]
 
     @classmethod
-    def dump(cls, key, verbose=False):
-        ret = {'key': cls[key].value[0], 'value': cls[key].value[1]}
+    def dump(cls, label, verbose=False):
+        """Dump one label to option.
+
+        Examples::
+
+            TaskState.dump('CREATED')  # {'key': 0, 'value': '新建'}
+
+        Returns:
+
+            dict: Dict of label's key and value. If label not exist,
+            raise ``KeyError``.
+        """
+
+        ret = {'key': cls[label].value[0], 'value': cls[label].value[1]}
         if verbose:
-            ret.update({'label': key})
+            ret.update({'label': label})
         return ret
 
     @classmethod
     def load(cls, val):
-        pos = 1 if isinstance(val, str) else 0
+        """Get label by key or value.
+
+        Examples::
+
+            TaskState.load(4)  # 'FINISHED'
+            TaskState.load('新建')  # 'CREATED'
+
+        Returns:
+            str|None: Label.
+        """
+
+        pos = 1 if isinstance(val, six.string_types) else 0
         for elem in cls:
             if elem.value[pos] == val:
                 return elem.name
 
     @classmethod
     def to_opts(cls, verbose=False):
+        """Enum to options.
+
+        Examples::
+
+            opts = TaskState.to_opts(verbose=True)
+            print(opts)
+
+            [{'key': 0, 'label': 'CREATED', 'value': u'新建'}, ...]
+
+        Returns:
+            list: List of dict which key is `key`, `value`, label.
+        """
+
         opts = []
         for elem in cls:
             opt = {'key': elem.value[0], 'value': elem.value[1]}
diff --git a/hobbit_core/hobbit/static/bootstrap/shire/pytest.ini.jinja2 b/hobbit_core/hobbit/static/bootstrap/shire/pytest.ini.jinja2
index 47823a2..fe39cf4 100644
--- a/hobbit_core/hobbit/static/bootstrap/shire/pytest.ini.jinja2
+++ b/hobbit_core/hobbit/static/bootstrap/shire/pytest.ini.jinja2
@@ -2,4 +2,4 @@
 env =
     LASK_APP=app/run.py
     FLASK_ENV=testing
-addopts = --cov . --cov-report term-missing -s -x -v -p no:warnings
+addopts = --cov . --cov-report term-missing -s -x -vv -p no:warnings
diff --git a/pytest.ini b/pytest.ini
index 73aa72c..93961b6 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -1,2 +1,2 @@
 [pytest]
-addopts = --cov hobbit_core --cov=tests --cov-report term-missing -s -x -v -p no:warnings
+addopts = --cov hobbit_core --cov=tests --cov-report term-missing -s -x -vv -p no:warnings
diff --git a/tests/test_db.py b/tests/test_db.py
new file mode 100644
index 0000000..6fa3418
--- /dev/null
+++ b/tests/test_db.py
@@ -0,0 +1,40 @@
+# -*- encoding: utf-8 -*-
+import pytest
+
+from hobbit_core.flask_hobbit import db
+
+from . import BaseTest
+
+
+class TestEnumExt(BaseTest):
+
+    @pytest.fixture
+    def TaskState(self):
+        class _TaskState(db.EnumExt):
+            CREATED = (0, u'新建')
+            FINISHED = (1, u'已完成')
+        return _TaskState
+
+    def test_strict_dump(self, TaskState):
+        assert 0 == TaskState.strict_dump('CREATED')
+        assert u'新建' == TaskState.strict_dump('CREATED', True)
+
+    def test_dump(self, TaskState):
+        assert {'key': 0, 'value': u'新建'} == TaskState.dump('CREATED')
+
+    def test_load(self, TaskState):
+        assert 'FINISHED' == TaskState.load(1)
+        assert 'CREATED' == TaskState.load(u'新建')
+        assert TaskState.load(100) is None
+
+    def test_to_opts(self, TaskState):
+        opts = TaskState.to_opts()
+        assert opts == [
+            {'key': 0, 'value': u'新建'},
+            {'key': 1, 'value': u'已完成'},
+        ]
+        opts = TaskState.to_opts(verbose=True)
+        assert opts == [
+            {'key': 0, 'label': 'CREATED', 'value': u'新建'},
+            {'key': 1, 'label': 'FINISHED', 'value': u'已完成'},
+        ]
diff --git a/tox.ini b/tox.ini
index e6b2b64..ed926ee 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,4 +9,4 @@ deps =
     py27: ipython==5.8.0
 commands =
     flake8 .
-    py.test --cov=hobbit_core --cov=tests --cov-report term-missing -s
+    py.test