Add a context manager to manage session handling

osmapi/OsmApi.py

@@ -251,13 +251,26 @@ def __init__(
         self._session = self._get_http_session()
 
     def __del__(self):
+        self.close()
+
+        return None
+
+    def __enter__(self):
+        self._session = self._get_http_session()
+        return self
+
+    def __exit__(self, *args):
+        self.close()
+
+    def close(self):
         try:
             if self._changesetauto:
                 self._changesetautoflush(True)
         except ResponseEmptyApiError:
             pass
 
-        return None
+        if self._session:
+            self._session.close()
 
     ##################################################
     # Capabilities                                   #

tests/helper_tests.py

@@ -23,6 +23,7 @@ def setupMock(self, status=200):
         mock_response.reason = "test reason"
         mock_response.content = 'test response'
         self.api._session.request = mock.Mock(return_value=mock_response)
+        self.api._session.close = mock.Mock()
         self.api._username = 'testuser'
         self.api._password = 'testpassword'
 
@@ -56,6 +57,15 @@ def test_passwordfile_with_colon(self):
         self.assertEquals('testuser', my_api._username)
         self.assertEquals('test:userpass', my_api._password)
 
+    def test_close_call(self):
+        self.api.close()
+        self.assertEquals(self.api._session.close.call_count, 1)
+
+    def test_close_context_manager(self):
+        with osmapi.OsmApi() as my_api:
+            my_api._session.close = mock.Mock()
+        self.assertEquals(my_api._session.close.call_count, 1)
+
     def test_http_request_get(self):
         response = self.api._http_request(
             'GET',