diff --git a/server_environment/__init__.py b/server_environment/__init__.py
index 3824827..0ff0f53 100644
--- a/server_environment/__init__.py
+++ b/server_environment/__init__.py
@@ -18,4 +18,8 @@
 #
 ##############################################################################
 from . import models
+# Add an alias to access to the 'serv_config' module as it is shadowed
+# the next line by an import of a variable with the same name.
+# We can't change the import of serv_config for backward compatibility.
+from . import serv_config as server_env
 from .serv_config import serv_config, setboolean
diff --git a/server_environment/models/server_env_mixin.py b/server_environment/models/server_env_mixin.py
index 7c3b717..09c5264 100644
--- a/server_environment/models/server_env_mixin.py
+++ b/server_environment/models/server_env_mixin.py
@@ -178,7 +178,7 @@ class ServerEnvMixin(models.AbstractModel):
                 value = getter(section_name, field_name)
             else:
                 value = getter(global_section_name, field_name)
-        except:
+        except Exception:
             _logger.exception(
                 "error trying to read field %s in section %s",
                 field_name,
diff --git a/server_environment/serv_config.py b/server_environment/serv_config.py
index 9807e13..4af4061 100644
--- a/server_environment/serv_config.py
+++ b/server_environment/serv_config.py
@@ -130,6 +130,7 @@ def _load_config():
     config_p = configparser.SafeConfigParser()
     # options are case-sensitive
     config_p.optionxform = str
+
     if _dir:
         _load_config_from_server_env_files(config_p)
     _load_config_from_rcfile(config_p)
diff --git a/server_environment/tests/__init__.py b/server_environment/tests/__init__.py
index 990f3cb..4c7aa90 100644
--- a/server_environment/tests/__init__.py
+++ b/server_environment/tests/__init__.py
@@ -18,3 +18,4 @@
 #
 ##############################################################################
 from . import test_server_environment
+from . import test_environment_variable
diff --git a/server_environment/tests/common.py b/server_environment/tests/common.py
new file mode 100644
index 0000000..37f3fb0
--- /dev/null
+++ b/server_environment/tests/common.py
@@ -0,0 +1,43 @@
+# Copyright 2018 Camptocamp (https://www.camptocamp.com).
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+
+import os
+from contextlib import contextmanager
+from unittest.mock import patch
+
+from odoo.tests import common
+from odoo.addons.server_environment import server_env
+from odoo.tools.config import config
+
+
+class ServerEnvironmentCase(common.TransactionCase):
+
+    def setUp(self):
+        super().setUp()
+        self._original_running_env = config.get('running_env')
+        config['running_env'] = 'testing'
+
+    def tearDown(self):
+        super().tearDown()
+        config['running_env'] = self._original_running_env
+
+    @contextmanager
+    def set_config_dir(self, path):
+        original_dir = server_env._dir
+        if path and not os.path.isabs(path):
+            path = os.path.join(os.path.dirname(__file__,), path)
+        server_env._dir = path
+        try:
+            yield
+        finally:
+            server_env._dir = original_dir
+
+    @contextmanager
+    def set_env_variables(self, public=None, secret=None):
+        newkeys = {}
+        if public:
+            newkeys['SERVER_ENV_CONFIG'] = public
+        if secret:
+            newkeys['SERVER_ENV_CONFIG_SECRET'] = secret
+        with patch.dict('os.environ', newkeys):
+            yield
diff --git a/server_environment/tests/test_environment_variable.py b/server_environment/tests/test_environment_variable.py
new file mode 100644
index 0000000..6d29dc5
--- /dev/null
+++ b/server_environment/tests/test_environment_variable.py
@@ -0,0 +1,45 @@
+# Copyright 2018 Camptocamp (https://www.camptocamp.com).
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+
+
+from odoo.addons.server_environment import server_env
+from .common import ServerEnvironmentCase
+
+
+class TestEnvironmentVariables(ServerEnvironmentCase):
+
+    def test_env_variables(self):
+        public = (
+            "[section]\n"
+            "foo=bar\n"
+            "bar=baz\n"
+        )
+        secret = (
+            "[section]\n"
+            "bar=foo\n"
+            "alice=bob\n"
+        )
+        with self.set_config_dir(None), \
+                self.set_env_variables(public, secret):
+            parser = server_env._load_config()
+            self.assertEqual(
+                list(parser.keys()),
+                ['DEFAULT', 'section']
+            )
+            self.assertDictEqual(
+                dict(parser['section'].items()),
+                {'alice': 'bob',
+                 'bar': 'foo',
+                 'foo': 'bar'}
+            )
+
+    def test_env_variables_override(self):
+        public = (
+            "[external_service.ftp]\n"
+            "user=foo\n"
+        )
+        with self.set_config_dir('testfiles'), \
+                self.set_env_variables(public):
+            parser = server_env._load_config()
+            val = parser.get('external_service.ftp', 'user')
+            self.assertEqual(val, 'foo')
diff --git a/server_environment/tests/test_server_environment.py b/server_environment/tests/test_server_environment.py
index 012f93d..2212a6c 100644
--- a/server_environment/tests/test_server_environment.py
+++ b/server_environment/tests/test_server_environment.py
@@ -17,11 +17,11 @@
 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 ##############################################################################
-from odoo.tests import common
-from odoo.addons.server_environment import serv_config
+from odoo.addons.server_environment import server_env
+from . import common
 
 
-class TestEnv(common.TransactionCase):
+class TestEnv(common.ServerEnvironmentCase):
 
     def test_view(self):
         model = self.env['server.config']
@@ -43,5 +43,9 @@ class TestEnv(common.TransactionCase):
         self.assertTrue(pass_checked)
 
     def test_value_retrival(self):
-        val = serv_config.get('external_service.ftp', 'user')
-        self.assertEqual(val, 'toto')
+        with self.set_config_dir('testfiles'):
+            parser = server_env._load_config()
+            val = parser.get('external_service.ftp', 'user')
+            self.assertEqual(val, 'testing')
+            val = parser.get('external_service.ftp', 'host')
+            self.assertEqual(val, 'sftp.example.com')
diff --git a/server_environment/tests/testfiles/default/base.conf b/server_environment/tests/testfiles/default/base.conf
new file mode 100644
index 0000000..566de2b
--- /dev/null
+++ b/server_environment/tests/testfiles/default/base.conf
@@ -0,0 +1,4 @@
+[external_service.ftp]
+host = sftp.example.com
+user = foo
+password = bar
\ No newline at end of file
diff --git a/server_environment/tests/testfiles/testing/base.conf b/server_environment/tests/testfiles/testing/base.conf
new file mode 100644
index 0000000..544e95b
--- /dev/null
+++ b/server_environment/tests/testfiles/testing/base.conf
@@ -0,0 +1,2 @@
+[external_service.ftp]
+user = testing