I am having trouble with the following code:
import praw
import argparse
# argument handling was here
def main():
r = praw.Reddit(user_agent='Python Reddit Image Grabber v0.1')
for i in range(len(args.subreddits)):
try:
r.get_subreddit(args.subreddits[i]) # test to see if the subreddit is valid
except:
print "Invalid subreddit"
else:
submissions = r.get_subreddit(args.subreddits[i]).get_hot(limit=100)
print [str(x) for x in submissions]
if __name__ == '__main__':
main()
subreddit
names are taken as arguments to the program.
When an invalid args.subreddits
is passed to get_subreddit
, it throws an exception which should be caught in the above code.
When a valid args.subreddit
name is given as an argument, the program runs fine.
But when an invalid args.subreddit
name is given, the exception is not thrown, and instead the following uncaught exception is outputted.
Traceback (most recent call last):
File "./pyrig.py", line 33, in <module>
main()
File "./pyrig.py", line 30, in main
print [str(x) for x in submissions]
File "/usr/local/lib/python2.7/dist-packages/praw/__init__.py", line 434, in get_content
page_data = self.request_json(url, params=params)
File "/usr/local/lib/python2.7/dist-packages/praw/decorators.py", line 95, in wrapped
return_value = function(reddit_session, *args, **kwargs)
File "/usr/local/lib/python2.7/dist-packages/praw/__init__.py", line 469, in request_json
response = self._request(url, params, data)
File "/usr/local/lib/python2.7/dist-packages/praw/__init__.py", line 342, in _request
response = handle_redirect()
File "/usr/local/lib/python2.7/dist-packages/praw/__init__.py", line 316, in handle_redirect
url = _raise_redirect_exceptions(response)
File "/usr/local/lib/python2.7/dist-packages/praw/internal.py", line 165, in _raise_redirect_exceptions
.format(subreddit))
praw.errors.InvalidSubreddit: `soccersdsd` is not a valid subreddit
I can't tell what I am doing wrong. I have also tried rewriting the exception code as
except praw.errors.InvalidSubreddit:
which also does not work.
File "./pyrig.py", line 30, in main
print [str(x) for x in submissions]
The problem, as your traceback indicates is that the exception doesn't occur when you call get_subreddit
In fact, it also doesn't occur when you call get_hot
. The first is a lazy invocation that just creates a dummy Subreddit
object but doesn't do anything with it. The second, is a generator that doesn't make any requests until you actually try to iterate over it.
Thus you need to move the exception handling code around your print statement (line 30) which is where the request is actually made that results in the exception.
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