#100DaysOfCode in Python Transcripts
Chapter: Days 52-54: Parsing RSS feeds with Feedparser
Lecture: Feedparser Sanity Check
0:00 Okay, one last little thing for you
0:02 which is a bit of a best practice
0:04 as always with Python scripts, you would
0:06 normally put in some sort of an error check,
0:08 just to make sure or a conditional check,
0:10 just to make sure everything is in place
0:13 before you run your script, right.
0:16 So in this case, what happens if one
0:19 of these tags doesn't exist in the feed?
0:23 Well, sometimes these RSS feeds out there
0:28 don't always include the default tags,
0:32 like title and link or description
0:34 or whatever else, okay, if that happens
0:37 well then your script's going to break.
0:38 So you should try and capture those errors
0:41 but right now, I'm not going to walk you
0:42 through error catching and testing
0:45 and trying except and everything that's
0:47 another module in itself, right.
0:50 So what I will show is just a really
0:53 quick, if statement that just works, okay.
0:57 So you could do if and then your tag name,
1:01 now I would definitely insist on title being in there,
1:05 so if title in feed.entries, we're looking at the
1:11 first item in feed.entries there.
1:16 Then we want you to run the full loop and that's it,
1:21 okay, that's all I'm looking at now then you can put
1:26 ls break or something like that or you could run your
1:30 try and except and what if you want to wrap around it.
1:32 But in this case, that's all we need, so we can save that
1:37 and then we can run that, so Python
1:40 and we'll get the same output as last time.
1:45 Okay, we can go and see all of that data
1:51 now just to prove that this actually worked,
1:53 here's what we can do, let's clear and let's
2:01 change the actual tag we're looking for.
2:04 So let's come up with something that's
2:05 definitely not going to be in there.
2:09 Let's see if I can spell, so that should be in every feed
2:12 right but unfortunately not so if Julian rocks
2:16 in feed.entries then run your forward.
2:20 Okay, let's run that and bang, nothing
2:25 happened, let's put title back in and there we have it,
2:32 okay, so that's it if you want to do some
2:35 sort of testing against it before you run
2:38 it, well that's the way to do it.
2:40 Okay, and that's pretty much feed parser nice and simple.