297569 - Subscription hangs indefinitely on "Verifying feed" when <link> is empty

Status: VERIFIED FIXED

(MailNews Core :: Feed Reader, defect)

Description

[[e-mail]]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.7) Gecko/20050414
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.7) Gecko/20050414

Thunderbird is apparently far too finicky about RSS feed
format, or tries to verify against the DTD or something
because this feed fails to get added during the lifetime
of this universe. The RSS plugin for mozilla mail, with
nearly identical functionality has no problems with it.

Reproducible: Always

Steps to Reproduce:
1. Try to add the given URL as an RSS feed, thunderbird sits and waits.
2. wait
3. wait
4. close the dialog
5. Are you sure you want to cancel? Yes.



Expected Results:  
Added the feed and parsed the items.

Comment 1

[[e-mail]]

This is the 1.1a about dialog shows version 1.0+ (20050531)

Comment 2

[Thomas K. (:tom)]

It was doing this for me too (latest trunk, just look at the timestamp of this
post, heh)

http://feedvalidator.org/check.cgi?url=http%3A%2F%2Fpthbb.org%2Fcgi-bin%2Fcomics.cgi
says you have a blank <link></link> on line 10, which is invalid.  Maybe this is
what thunderbird chokes on?

Actually, after writing that I set about testing it.  Guess what.  Setting that
link to not be blank fixed the whole thing and tb got all the items fine, i was
able to view CTRL+ALT+DEL in thunderbird.

editing summary accordingly

Comment 3

[Thomas K. (:tom)]

oops, if i found out why the bug was happening, i also found out that the bug is
happening.

confirming

Comment 4

[Thomas K. (:tom)]

related to bug 296998?

Comment 5

[Mike Cowperthwaite]

It appears that the specified feed has now put a URL inside its <link> tag, so 
it doesn't generate this problem any longer.

xref bug 306997, which has URL for a feed that (in current trunk/branch builds) 
doesn't load -- altho that feed *also* has a non-blank <link>.

Comment 6

[Mike Cowperthwaite]

*** Bug 314954 has been marked as a duplicate of this bug. ***

Comment 7

[Mike Cowperthwaite]

From the dupe, this feed exhibits the same problem:
  http://www.theonion.com/content/feeds/weekly
Hangs with TB 1.5a2-1006 and 1.6a1-1101.

Comment 8

[Mike Cowperthwaite]

Bug 315600 is nearly identical to this, except the problem occurs on an empty <title> element, rather than <link>.  As noted in that bug, an error is shown in the JavaScript console, which implies two things: fixing the immediate symptom should be easy; and the verify code should be exception-aware and halt itself, rather than hanging, when the exception is thrown.

Comment 9

[Mike Cowperthwaite]

*** Bug 337067 has been marked as a duplicate of this bug. ***

Comment 10

[Chris Wren]

I'm attaching a patch that allows me, at least, to add an rss feed with an empty title property.

This is not production code, but maybe it'll focus the search for someone.  I have no idea what parts of the code might be affected by this.  I don't really know what the data scructures are.  But I blindly caught the offered eception and ignored it, and nothing bad seems to have happened.  OSmeone who understands the deeper implications of the exception might want ot look into this.

the only negative is that the feed is titles with the (rather long and ugly) url.

1.5.0.7 (20060909)

Chris

the offending iWeb feed:
http://rss.mac.com/champart/iWeb/Paint%20Squared%3A%20%208%20Days%20a%20Week/Paint%20Squared%3A%20%208%20Days%20a%20Week/rss.xml

Comment 11

[Chris Wren]

Attachment: non-production patch

This is "works for me" code that needs the attention of someone who knows
what's really going on in this module.

Comment 12

[[:Aleksej]]

Seen on Linux with
version 3.0a1pre (2007071203)
version 2.0.0.5pre (20070712)
at http://library.fes.de/library/html/rss/digbib/rss-all.xml

Comment 13

[Christian Schmidt]

Attachment: Support for entries without links

This patch adds support for feeds without links. I am not really sure about the intention behind item.id, item.isStoredWithId and item.messageID, though.

The patch still needs some testing.

Comment 14

[Magnus Melin [:mkmelin]]

Did you have an URL that causes the problem? 

Comment 15

[Christian Schmidt]

Attachment: Support for entries without links, v2

Comment 16

[Christian Schmidt]

Attachment: Testcase

(In reply to comment #14)
> Did you have an URL that causes the problem? 
This is an artificial feed that causes the problem. According to http://feedvalidator.org/ it is valid RSS.

Comment 17

[Scott MacGregor]

Comment on attachment 290454 [details] [diff] [review]
Support for entries without links, v2

bouncing this to Phil whose always enjoyed reviewing the RSS code :)

Comment 18

[Phil Ringnalda (:philor)]

Comment on attachment 290454 [details] [diff] [review]
Support for entries without links, v2

One of these days, we really need to get some useful explanatory comments in this code; say, once we find someone who understands it.

But to the extent I do, this seems like the right thing to do, so r=philringnalda, and thanks for puzzling it out, Christian!

> bouncing this to Phil whose always enjoyed reviewing the RSS code

Scott, you've got a typo there, I think you meant "Bouncing this to Phil. Who's always enjoyed reviewing the RSS code?"

Comment 19

[Christian Schmidt]

Who's on first? :-)

Thanks for the review.

Comment 20

[Reed Loden [:reed]]

Checking in mail/extensions/newsblog/content/FeedItem.js;
/cvsroot/mozilla/mail/extensions/newsblog/content/FeedItem.js,v  <--  FeedItem.js
new revision: 1.42; previous revision: 1.41
done
Checking in mail/extensions/newsblog/content/feed-parser.js;
/cvsroot/mozilla/mail/extensions/newsblog/content/feed-parser.js,v  <--  feed-parser.js
new revision: 1.21; previous revision: 1.20
done