Handle exceptions when closing DB connection

When using JayDeBeApi, closing the connection can cause the following
exception to be raised:

jpype._core.JVMNotRunning: Java Virtual Machine is not running

Since we're closing the connection anyway, it seems like the best
behavior is to log the exception and continue on.

Fixes #71

Author: kadler

src/itoolkit/transport/database.py

@@ -1,4 +1,6 @@
 # -*- coding: utf-8 -*-
+import logging
+
 from .base import XmlServiceTransport
 
 __all__ = [
@@ -81,4 +83,12 @@ def _call(self, tk):
         return "".join(row[0] for row in cursor.fetchall()).rstrip('\0')
 
     def _close(self):
-        self.conn.close()
+        try:
+            self.conn.close()
+        except RuntimeError:
+            # JayDeBeApi can fail to close a connection with
+            # jpype._core.JVMNotRunning: Java Virtual Machine is not running
+            #
+            # Doesn't seem to be anything reasonable to do but log the
+            # exception and continue.
+            logging.exception("Unexpected exception closing database connection")

tests/conftest.py

@@ -67,6 +67,13 @@ def database_execute():
     return mock_database(use_callproc=False)
 
 
+@pytest.fixture
+def database_close_exception():
+    conn = mock_database(use_callproc=True)
+    conn.close.side_effect = RuntimeError
+    return conn
+
+
 @pytest.fixture
 def database():
     return mock_database(use_callproc=True)

tests/test_unit_transport_database.py

@@ -71,3 +71,21 @@ def test_database_transport_call_raises_when_closed(database_execute):
     with pytest.raises(TransportClosedException):
         tk = iToolKit()
         out = transport.call(tk)
+
+
+def test_database_transport_logs_exception_on_close(database_close_exception, caplog, capsys):
+    schema = 'MYSCHEMA'
+    transport = DatabaseTransport(database_close_exception, schema=schema)
+
+    tk = iToolKit()
+    out = transport.call(tk)
+
+    with capsys.disabled():
+        transport.close()
+
+    assert len(caplog.records) == 1
+    l = caplog.records[0]
+    assert l.levelname == "ERROR"
+    assert 'Unexpected exception' in l.message
+
+    caplog.clear()