1517092 - Server error causes RSS feed load error

Status: RESOLVED INVALID

(MailNews Core :: Feed Reader, defect)

Description

[Meik Neubauer]

Attachment: news.rss.feed

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:64.0) Gecko/20100101 Firefox/64.0

Steps to reproduce:

An already subscribed feed failed to load on 2019/01/01.
Feed URL: https://www.stuttgarter-zeitung.de/news.rss.feed
(redirected from http://www.stuttgarter-zeitung.de/news.rss.feed)


Actual results:

Console log shows:

XML Parsing Error: XML or text declaration not at start of entity
Location: https://www.stuttgarter-zeitung.de/news.rss.feed
Line Number 2, Column 1:  news.rss.feed:2:1
2019-01-01 09:40:09	Feeds	INFO	Feed.onDownloaded: request errType:errName:statusCode - Network:NetworkError:503

2019-01-01 09:40:09	Feeds	WARN	downloaded: updates disabled due to error, check the url - http://www.stuttgarter-zeitung.de/news.rss.feed

2019-01-01 09:40:09	Feeds	INFO	downloaded: Update: News Feeds/News/General/StZ/Stuttgarter Zeitung - Nachrichten des Tages -> http://www.stuttgarter-zeitung.de/news.rss.feed could not be found. Please check the name and try again.



Expected results:

The server's response is actually a valid feed.
The XML-Header of the response contains the XML namespace definition

xmlns:taxo="http://purl.org/rss/1.0/modules/taxonomy/"

which is actually never referenced within the XML document.
However, this URL resolves to an HTTP 404.
I assume this is the root cause of the overall failure. (But I may be wrong. Anyway, I could not spot any other apparent problem.)

Maybe a question of philosophical magnitude, but I would assume that an unused namespace should not cause such a failure.

Comment 1

[alta88]

The assumptions and conclusions are quite incorrect. The log clearly states what is wrong - a 503 error code which passed on a document that was not valid xml. Both of those urls work now.  All feeds failures are due to network or publisher errors, either permanent or transient.

Please avoid filing frivolous bugs, as they expend scarce time resources.

Comment 2

[Meik Neubauer]

Of course, I saw the 503, but this (or any other network/server error) was not reproducible outside Thunderbird or with other feed domains in Thunderbird - whereas the error appeared permanent within Thunderbird for only that domain. I repeated this 20x or so - always with the same result. I deem it unlikely that the server or network failed only on the exact milliseconds that the requests came from Thunderbird, when "parallel" requests (i.e. within 1-2 seconds ahead/behind) from Firefox did not fail.

Comment 3

[Meik Neubauer]

Could the error be related to an attempt by Thunderbird to fetch a favicon from the server?
I remember I had seen an error in the Firefox log for the favicon when I was doing the parallel requests. I did not pay much attention to this, as the XML did not contain any link to a favicon. But thinking about this now... it may be related.

Would Thunderbird fail to display a valid feed if there was a problem fetching the favicon (wherever it is trying to get it from)?

Comment 4

[Jorg K (CEST = GMT+2)]

https://www.stuttgarter-zeitung.de/news.rss.feed works for me, I've just added it. 503 is "service unavailable". We had a few cases of 403 "Forbidden" where TB was explicitly blocked (bug 1344513, bug 1355733).