murgatroid99 murgatroid99 - 3 months ago 12
Python Question

In Python try until no error

I have a piece of code in Python that seems to cause an error probabilistically because it is accessing a server and sometimes that server has a 500 internal server error. I want to keep trying until I do not get the error. My solution was:

while True:
try:
#code with possible error
except:
continue
else:
#the rest of the code
break


This seems like a hack to me. Is there a more Pythonic way to do this?

Answer

It won't get much cleaner. This is not a very clean thing to do. At best (which would be more readable anyway, since the condition for the break is up there with the while), you could create a variable result = None and loop while it is None. You should also adjust the variables and you can replace continue with the semantically perhaps correct pass (you don't care if an error occurs, you just want to ignore it) and drop the break - this also gets the rest of the code, which only executes once, out of the loop. Also note that bare except: clauses are evil for reasons given in the documentation.

Example incorporating all of the above:

result = None
while result is None:
    try:
        # connect
        result = get_data(...)
    except:
         pass
# other code that uses result but is not involved in getting it