Throw exception if version number <4.6 (#220)

With #188, we need to prevent users using OmniSci <=4.5 from using pymapd >= 0.11. This is because of the backend change to switch encoding of dates from epoch seconds to epoch days. It was determined by myself and JP that it's better to throw the error on login, rather than allow user to have a script blow up unexpectedly once using columnar load.

pymapd/connection.py

@@ -28,6 +28,8 @@
 from ._pandas_loaders import build_row_desc, _serialize_arrow_payload
 from . import _pandas_loaders
 
+from packaging.version import Version
+
 
 ConnectionInfo = namedtuple("ConnectionInfo", ['user', 'password', 'host',
                                                'port', 'dbname', 'protocol'])
@@ -174,6 +176,15 @@ def __init__(self,
         except TMapDException as e:
             raise _translate_exception(e) from e
 
+        # if OmniSci version <4.6, raise RuntimeError, as data import can be
+        # incorrect for columnar date loads
+        # Caused by https://github.com/omnisci/pymapd/pull/188
+        semver = self._client.get_version()
+        if Version(semver.split("-")[0]) < Version("4.6"):
+            raise RuntimeError(f"Version {semver} of OmniSci detected. "
+                               "Please use pymapd <0.11. See release notes "
+                               "for more details.")
+
     def __repr__(self):
         # type: () -> str
         tpl = ('Connection(mapd://{user}:***@{host}:{port}/{dbname}?protocol'

tests/test_connection.py

@@ -6,6 +6,7 @@
 from pymapd._parsers import ColumnDetails, _extract_column_details
 
 
+@pytest.mark.usefixtures("mapd_server")
 class TestConnect:
 
     def test_host_specified(self):
@@ -16,33 +17,21 @@ def test_raises_right_exception(self):
         with pytest.raises(OperationalError):
             connect(host='localhost', protocol='binary', port=1234)
 
-    def test_close(self, mock_client):
-        con = connect(user='user', password='password',
-                      host='localhost', dbname='dbname')
-        assert con.closed == 0
-        con.close()
-        assert con.closed == 1
-
-    def test_connect(self, mock_client):
-        con = connect(user='user', password='password',
-                      host='localhost', dbname='dbname')
-        assert mock_client.call_count == 1
-        assert con._client.connect.call_args == [
-            ('user', 'password', 'dbname')
-        ]
+    def test_close(self):
+        conn = connect(user='mapd', password='HyperInteractive',
+                       host='localhost', dbname='mapd')
+        assert conn.closed == 0
+        conn.close()
+        assert conn.closed == 1
 
-    def test_context_manager(self, mock_client):
-        con = connect(user='user', password='password',
-                      host='localhost', dbname='dbname')
+    def test_context_manager(self, con):
         with con as cur:
             pass
 
         assert isinstance(cur, Cursor)
         assert con.closed == 0
 
-    def test_commit_noop(self, mock_client):
-        con = connect(user='user', password='password',
-                      host='localhost', dbname='dbname')
+    def test_commit_noop(self, con):
         result = con.commit()  # it worked
         assert result is None
 

tests/test_cursor.py

@@ -23,11 +23,6 @@ def test_empty_iterable(self):
         result = list(c)
         assert result == []
 
-    def test_context_manager(self, mock_connection):
-        c = mock_connection.cursor()
-        with c:
-            c.execute("select 1;")
-
     def test_escape_basic(self):
         query = "select * from foo where bar > :baz"
         result = str(_bind_parameters(query, {"baz": 10}))