Reputation: 3477
I use sqlachemy to connect to a remote database but I do not know the type (can be PostgreSQL, MariaDB, etc.). I try them in a loop and I keep the first working driver:
for driver in drivers:
try:
uri = get_uri_from_driver(driver)
engine = create_engine(uri, echo=False)
print('Try connection')
con = engine.engine.connect()
# Try to get some lines
return engine
except Exception:
continue
return None
In some case the con = engine.engine.connect() does not end and it happens when you try the MySQL driver to connect to something which is not MySQL (Oracle).
Questions:
How can I set a timeout to this?
If I cannot, is there any other way to achieve this ? (I will for example base the test order with the default port but I would like to be able to kill the connect() after some seconds.
EDIT:
This code is in a Django so I cannot use signal/alarm because of multi-threading.
Upvotes: 1
Views: 864
Reputation: 2454
This can be done with a generic timeout solution like in:
What should I do if socket.setdefaulttimeout() is not working?
import signal
class Timeout():
"""Timeout class using ALARM signal"""
class TimeoutException(Exception): pass
def __init__(self, sec):
self.sec = sec
def __enter__(self):
signal.signal(signal.SIGALRM, self.raise_timeout)
signal.alarm(self.sec)
def __exit__(self, *args):
signal.alarm(0) # disable alarm
def raise_timeout(self, *args):
raise Timeout.TimeoutException()
# In your example
try:
uri = get_uri_from_driver(driver)
engine = create_engine(uri, echo=False)
print('Try connection')
with Timeout(10):
con = engine.engine.connect()
# Try to get some lines
return engine
except Exception:
continue
Upvotes: 1