fix: catching the wrong exception class (#68)

Author: karenc-bq

aws_wrapper/dialect.py

@@ -18,11 +18,14 @@
 from contextlib import closing
 from enum import Enum, auto
 from logging import getLogger
-from typing import Dict, Optional, Protocol, Tuple, runtime_checkable
+from typing import (TYPE_CHECKING, Dict, Optional, Protocol, Tuple,
+                    runtime_checkable)
+
+if TYPE_CHECKING:
+    from aws_wrapper.pep249 import Connection
 
 from aws_wrapper.errors import AwsWrapperError
 from aws_wrapper.hostinfo import HostInfo
-from aws_wrapper.pep249 import Connection, Error
 from aws_wrapper.utils.properties import (Properties, PropertiesUtils,
                                           WrapperProperties)
 from aws_wrapper.utils.rdsutils import RdsUtils
@@ -162,7 +165,7 @@ def is_dialect(self, conn: Connection) -> bool:
                     for column_value in record:
                         if "mysql" in column_value.lower():
                             return True
-        except Error:
+        except Exception:
             pass
 
         return False
@@ -203,8 +206,10 @@ def is_dialect(self, conn: Connection) -> bool:
                 aws_cursor.execute('SELECT 1 FROM pg_proc LIMIT 1')
                 if aws_cursor.fetchone() is not None:
                     return True
-        except Error:
-            pass
+        except Exception:
+            # Executing the select statements will start a transaction, if the queries failed due to invalid syntax,
+            # the transaction will be aborted, no further commands can be executed. We need to call rollback here.
+            conn.rollback()
 
         return False
 
@@ -252,7 +257,7 @@ def is_dialect(self, conn: Connection) -> bool:
                 for record in aws_cursor:
                     if "mariadb" in record[0].lower():
                         return True
-        except Error:
+        except Exception:
             pass
 
         return False
@@ -286,7 +291,7 @@ def is_dialect(self, conn: Connection) -> bool:
                     for column_value in record:
                         if "source distribution" in column_value.lower():
                             return True
-        except Error:
+        except Exception:
             pass
 
         return False
@@ -318,8 +323,10 @@ def is_dialect(self, conn: Connection) -> bool:
                     if rds_tools and not aurora_utils:
                         return True
 
-        except Error:
-            pass
+        except Exception:
+            # Executing the select statements will start a transaction, if the queries failed due to invalid syntax,
+            # the transaction will be aborted, no further commands can be executed. We need to call rollback here.
+            conn.rollback()
         return False
 
     @property
@@ -345,7 +352,7 @@ def is_dialect(self, conn: Connection) -> bool:
                 # If variable with such a name is presented then it means it's an Aurora cluster
                 if aws_cursor.fetchone() is not None:
                     return True
-        except Error:
+        except Exception:
             pass
 
         return False
@@ -392,8 +399,10 @@ def is_dialect(self, conn: Connection) -> bool:
                     has_topology = True
 
             return has_extensions and has_topology
-        except Error:
-            pass
+        except Exception:
+            # Executing the select statements will start a transaction, if the queries failed due to invalid syntax,
+            # the transaction will be aborted, no further commands can be executed. We need to call rollback here.
+            conn.rollback()
 
         return False
 

aws_wrapper/failover_plugin.py

@@ -67,7 +67,7 @@ def __init__(self, plugin_service: PluginService, props: Properties):
         self._last_exception: Optional[Exception] = None
         self._rds_utils = RdsUtils()
         self._rds_url_type: RdsUrlType = self._rds_utils.identify_rds_type(self._properties.get("host"))
-        FailoverPlugin._SUBSCRIBED_METHODS.add(*self._plugin_service.network_bound_methods)
+        FailoverPlugin._SUBSCRIBED_METHODS.update(*self._plugin_service.network_bound_methods)
 
     def init_host_provider(
             self,