def _check_connection(self):
"""
Return false if the connection is broken
:rtype: bool
"""
# If the connection is not present return False
if not self._conn:
return False
# Check if the connection works by running 'SELECT 1'
cursor = None
try:
cursor = self._conn.cursor()
cursor.execute(self.CHECK_QUERY)
except psycopg2.DatabaseError:
# Connection is broken, so we need to reconnect
self.close()
# Raise an error if reconnect is not allowed
if not self.allow_reconnect:
raise PostgresConnectionError(
"Connection lost, reconnection not allowed")
return False
finally:
if cursor:
cursor.close()
return True
def connect(self):
"""
Generic function for Postgres connection (using psycopg2)
"""
if not self._conn:
try:
self._conn = psycopg2.connect(self.conninfo)
# If psycopg2 fails to connect to the host,
# raise the appropriate exception
except psycopg2.DatabaseError as e:
raise PostgresConnectionError(str(e).strip())
# Register the connection to the live connections list
_live_connections.append(self)
return self._conn
def connect(self):
"""
Generic function for Postgres connection (using psycopg2)
"""
if self._conn and self._conn.closed:
# Close the broken connection and let the following code to open
# it again
self.close()
# Raise an error if the connection is broken
# and reconnect is not allowed
if not self.allow_reconnect:
raise PostgresConnectionError(
"The connection is broken and reconnection is not allowed")
if not self._conn:
try:
self._conn = psycopg2.connect(self.conninfo)
# If psycopg2 fails to connect to the host,
# raise the appropriate exception
except psycopg2.DatabaseError as e:
raise PostgresConnectionError(str(e).strip())
# Register the connection to the live connections list
_live_connections.append(self)
return self._conn
def connect(self):
"""
Connect to the PostgreSQL server. It reuses an existing connection.
"""
if self._conn:
return self._conn
self._conn = super(PostgreSQLConnection, self).connect()
if (self._conn.server_version >= 90000 and
'application_name' not in self.conn_parameters):
try:
cur = self._conn.cursor()
cur.execute('SET application_name TO barman')
cur.close()
# If psycopg2 fails to set the application name,
# raise the appropriate exception
except psycopg2.ProgrammingError as e:
raise PostgresConnectionError(
"Cannot set the application name: %s" % str(e).strip())
return self._conn