A strange rss feed behaviour

J_F_Moyen · Janvier 21, 2009, 1:07

Bonjour,

J'ai posé ma question de flux rss sur le newsgroup opera; la réponse ne m'a pas plus éclairé mais comporte, il me semble, des commentaires intéressants sur la syntaxe du flux rss diffusé par spip (et partant sur la rédaction du fichier backend). Si des développeurs passent par ici, le message et les commentaires qu'il contient sont peut être plus intéressants pour vous que pour moi.

Si vous voulez répondre à l'auteur, faites le sur le newsgroup d'origine à opera.mail+news sur nntp://news.opera.com

JF

---- Forwarded Usenet-message ----
From: Calc-Yolatuh <relgoshan@gmail.com>
Newsgroups: opera.mail+news
Subject: Re: A strange rss feed behaviour
Date: Mon, 19 Jan 2009 23:19:04 +0200
URL: news://<op.un0v52uvb90lyj@kings_tower>

Eh, this'll be a kinda tl;dr sort of message. (too long; don't read)

Firstly I've just got to mention that the site's base encoding is listed
as perfectly valid utf-8 standard text.

Also the french site uses xmlns:dc and xmlns:content descriptors, pointing
to purl.org, while a working site laid out below uses the xmlns:atom
descriptor and points to the 2005 Atom standards page.

(The purl.org links redirect to two other sites, and the material found
there indicates that free.fr's standard is very much out of date. One page
has had no activity since 2002, and the other shows a gap from 1999.)

This is a full recent dump of the page source from your personal feed.
There is a separator at the end, followed by a dump from a working site.

<?xml version="1.0" encoding="utf-8"?>
<rss version="2.0"
xmlns:dc="DCMI: DCMI Metadata Terms;
xmlns:content="http://purl.org/rss/1.0/modules/content/"

<channel>
  <title>Géologie et géo-tourisme</title>
  <link>http://jfmoyen.free.fr/</link>
  <description></description>
  <language>fr</language>
  <generator>SPIP - www.spip.net</generator>

  <item>
    <title>Les hauts du Pilat</title>
    <link>Les hauts du Pilat, par Jeff - Géologie et géo-tourisme;
    <guid
isPermaLink="true">Les hauts du Pilat, par Jeff - Géologie et géo-tourisme;
    <dc:date>2009-01-19T08:43:49Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Un peu de neige

-
<a href="France - Géologie et géo-tourisme;
rel="directory">045. France</a>

</description>

  <item>
    <title>Port-Béni</title>
    <link>Free.fr - Pages personnelles: Trop de slots demandes;
    <guid
isPermaLink="true">Free.fr - Pages personnelles: Trop de slots demandes;
    <dc:date>2009-01-16T13:53:34Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Bretagne Nord et (presque) vieux cailloux

-
<a href="France - Géologie et géo-tourisme;
rel="directory">045. France</a>

</description>

  <item>
    <title>Bretagne Nord</title>
    <link>Free.fr - Pages personnelles: Trop de slots demandes;
    <guid
isPermaLink="true">Free.fr - Pages personnelles: Trop de slots demandes;
    <dc:date>2009-01-16T13:52:42Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Côte, îles et vagues

-
<a href="France - Géologie et géo-tourisme;
rel="directory">045. France</a>

</description>

  <item>
    <title>Fabrique planaire, fabrique linéaire</title>
    <link>Free.fr - Pages personnelles: Trop de slots demandes;
    <guid
isPermaLink="true">Free.fr - Pages personnelles: Trop de slots demandes;
    <dc:date>2009-01-16T12:26:31Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Foliation, linéation et différentes
géométries de déformation ductile.

-
<a href="Free.fr - Pages personnelles: Trop de slots demandes;
rel="directory">033. Photos géologiques</a>

</description>

  <item>
    <title>Le complexe du Bushveld - Présentation ppt pour R2M</title>
    <link>Free.fr - Pages personnelles: Trop de slots demandes;
    <guid
isPermaLink="true">Free.fr - Pages personnelles: Trop de slots demandes;
    <dc:date>2009-01-15T14:24:47Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Diapos d'une conférence

-
<a href="http://jfmoyen.free.fr/spip.php?rubrique4"
rel="directory">031. Polys</a>

</description>

  <item>
    <title>Message de service (2)</title>
    <link>http://jfmoyen.free.fr/spip.php?article261</link>
    <guid
isPermaLink="true">http://jfmoyen.free.fr/spip.php?article261</guid>
    <dc:date>2009-01-07T13:39:27Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Quelques modifications techniques

-
<a href="http://jfmoyen.free.fr/spip.php?rubrique9"
rel="directory">99. Bavardages</a>

</description>

</item>

  <item>
    <title>Message de service (commentaires)</title>
    <link>http://jfmoyen.free.fr/spip.php?article260</link>
    <guid
isPermaLink="true">http://jfmoyen.free.fr/spip.php?article260</guid>
    <dc:date>2008-10-23T07:46:29Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Les commentaires sont désormais modérés.

-
<a href="http://jfmoyen.free.fr/spip.php?rubrique9"
rel="directory">99. Bavardages</a>

</description>

</item>

  <item>
    <title>HDR</title>
    <link>http://jfmoyen.free.fr/spip.php?article259</link>
    <guid
isPermaLink="true">http://jfmoyen.free.fr/spip.php?article259</guid>
    <dc:date>2008-10-09T16:00:45Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Mémoire HDR

-
<a href="http://jfmoyen.free.fr/spip.php?rubrique2"
rel="directory">02. Publications et travaux</a>

</description>

  <item>
    <title>Livrets-guides 2008</title>
    <link>http://jfmoyen.free.fr/spip.php?article258</link>
    <guid
isPermaLink="true">http://jfmoyen.free.fr/spip.php?article258</guid>
    <dc:date>2008-10-02T07:29:36Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Itinéraire et descriptions pour l'excursion 2008

-
<a href="http://jfmoyen.free.fr/spip.php?rubrique35"
rel="directory">344. Afrique du Sud 2008</a>

</description>

  <item>
    <title>Badplaas - la fin d'un monde ?</title>
    <link>http://jfmoyen.free.fr/spip.php?article257</link>
    <guid
isPermaLink="true">http://jfmoyen.free.fr/spip.php?article257</guid>
    <dc:date>2008-09-29T09:59:51Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Fragments de récits dans l'Afrique du Sud rurale

-
<a href="http://jfmoyen.free.fr/spip.php?rubrique37"
rel="directory">06. Frog biltong</a>

</description>

</channel>

</rss>

------------------------------------------------------------------------

The following is a full recent dump of the page source from a feed
provider that I have had no issues with.
There are a few more comments after another separator. As shown, site is
"crazymanga.be"

<rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom">
<channel>
       <atom:link href="http://crazymanga.be/rss.php" rel="self"
type="application/rss+xml" />
       <title>Crazy's Manga's: RSS</title>
       <description>Latest additions to the site</description>
       <link>http://crazymanga.be</link>
       <language>en</language>
       <image>
           <title>Crazy's Manga's: RSS</title>
           <url>http://crazymanga.be/images/rss.png</url>
           <link>http://crazymanga.be</link>
       </image>
       <item>
           <title>Moyashimon c091[Raw]</title>
           <link>http://crazymanga.be/Manga/285</link>
           <description>Moyashimon c091[Raw]</description>
           <pubDate>1232387857</pubDate>
           <guid>4974bf11-5b3c-4c16-9ab4-6a75439f3c61</guid>
       </item>
       <item>
           <title>Tona-Gura v05 c29[FoOls]</title>
           <link>http://crazymanga.be/Manga/147</link>
           <description>Tona-Gura v05 c29[FoOls]</description>
           <pubDate>1232384115</pubDate>
           <guid>4974b073-6bcc-43da-940a-634a439f3c61</guid>
       </item>
       <item>
           <title>Ace of the Diamond c010 [3TP]</title>
           <link>http://crazymanga.be/Manga/49661e60-4548-428d-856e-2f4e439f3c61</link>
           <description>Ace of the Diamond c010 [3TP]</description>
           <pubDate>1232384103</pubDate>
           <guid>4974b067-2b34-4159-85fb-6493439f3c61</guid>
       </item>
       <item>
           <title>Yuutai Nova v01 ch08[Hidoi]</title>
           <link>http://crazymanga.be/Manga/49640d0a-552c-49df-bd78-42ce439f3c61</link>
           <description>Yuutai Nova v01 ch08[Hidoi]</description>
           <pubDate>1232364166</pubDate>
           <guid>49746286-8f60-4592-87a9-3be9439f3c61</guid>
       </item>
       <item>
           <title>Fly High v01ch01 [SH].zip</title>
           <link>http://crazymanga.be/Manga/4974603b-4a1c-4af0-b96f-32ec439f3c61</link>
           <description>Fly High v01ch01 [SH].zip</description>
           <pubDate>1232363579</pubDate>
           <guid>4974603b-d65c-45de-8b8c-32ec439f3c61</guid>
       </item>
       <item>
           <title>Ashita no Yoichi! - v08[Raw]</title>
           <link>http://crazymanga.be/Manga/89</link>
           <description>Ashita no Yoichi! - v08[Raw]</description>
           <pubDate>1232363290</pubDate>
           <guid>49745f1a-6f80-48be-a8ee-37e5439f3c61</guid>
       </item>
       <item>
           <title>Star Ocean 2 Second Evolution ch05[Project Kurai
Ryu]</title>
           <link>http://crazymanga.be/Manga/48d3d65f-7b8c-4e43-b0da-2339425a6735</link>
           <description>Star Ocean 2 Second Evolution ch05[Project Kurai
Ryu]</description>
           <pubDate>1232360174</pubDate>
           <guid>497452ee-0ac0-4565-a46a-3071439f3c61</guid>
       </item>
       <item>
           <title>Golden Boy v06 Study40[Kna]</title>
           <link>http://crazymanga.be/Manga/4923dc6e-49d0-437e-85ac-4b24425a6735</link>
           <description>Golden Boy v06 Study40[Kna]</description>
           <pubDate>1232344546</pubDate>
           <guid>497415e2-08b8-4393-8810-0d87439f3c61</guid>
       </item>
       <item>
           <title>Toshiue no Hito v05 c27[FT]</title>
           <link>http://crazymanga.be/Manga/187</link>
           <description>Toshiue no Hito v05 c27[FT]</description>
           <pubDate>1232343559</pubDate>
           <guid>49741207-8740-4dcd-aad1-0605439f3c61</guid>
       </item>
       <item>
           <title>Umisho c043[Nonbiri]</title>
           <link>http://crazymanga.be/Manga/21</link>
           <description>Umisho c043[Nonbiri]</description>
           <pubDate>1232343545</pubDate>
           <guid>497411f9-3228-4c3c-9d30-0af0439f3c61</guid>
       </item>
       <item>
           <title>Bamboo Blade 56[CXC]</title>
           <link>http://crazymanga.be/Manga/67</link>
           <description>Bamboo Blade 56[CXC]</description>
           <pubDate>1232331743</pubDate>
           <guid>4973e3df-ec10-4901-8ea7-7243439f3c61</guid>
       </item>
       <item>
           <title>Bamboo Blade B ch01[CXC].zip</title>
           <link>http://crazymanga.be/Manga/4973e340-eec4-4cac-8f06-70d8439f3c61</link>
           <description>Bamboo Blade B ch01[CXC].zip</description>
           <pubDate>1232331584</pubDate>
           <guid>4973e340-8818-4c72-bc6b-70d8439f3c61</guid>
       </item>
       <item>
           <title>Ojiichan wa Shounen Tantei v04 c24[Desudesu]</title>
           <link>http://crazymanga.be/Manga/488778fa-f32c-4cbb-a224-4421425a6735</link>
           <description>Ojiichan wa Shounen Tantei v04
c24[Desudesu]</description>
           <pubDate>1232283999</pubDate>
           <guid>4973295f-a510-4cd3-9dcf-3a59439f3c61</guid>
       </item>
       <item>
           <title>SaruLock v03c22[Illuminati-Manga]</title>
           <link>http://crazymanga.be/Manga/48caad98-3d04-4330-aa13-2116425a6735</link>
           <description>SaruLock v03c22[Illuminati-Manga]</description>
           <pubDate>1232275122</pubDate>
           <guid>497306b2-c8a4-4759-8976-745c439f3c61</guid>
       </item>
       <item>
           <title>Team Medical Dragon v06 c44[ETC]</title>
           <link>http://crazymanga.be/Manga/48ca455f-4c74-4262-8aef-7a56425a6735</link>
           <description>Team Medical Dragon v06 c44[ETC]</description>
           <pubDate>1232273914</pubDate>
           <guid>497301fa-78a0-4b6e-a527-73a3439f3c61</guid>
       </item>
       <item>
           <title>Usagi Drop v02 ch12[J-SiS]</title>
           <link>http://crazymanga.be/Manga/342</link>
           <description>Usagi Drop v02 ch12[J-SiS]</description>
           <pubDate>1232273483</pubDate>
           <guid>4973004b-18e8-41f2-ae75-61e9439f3c61</guid>
       </item>
       <item>
           <title>Smash! ch113[Raw]</title>
           <link>http://crazymanga.be/Manga/487a0df9-18f0-485b-afb8-47be425a6735</link>
           <description>Smash! ch113[Raw]</description>
           <pubDate>1232272577</pubDate>
           <guid>4972fcc1-82d0-4e05-800b-6de3439f3c61</guid>
       </item>
       <item>
           <title>Psyren ch54[Hitsugaara]</title>
           <link>http://crazymanga.be/Manga/484962c3-e978-43c7-8f4b-1ba14e81ae29</link>
           <description>Psyren ch54[Hitsugaara]</description>
           <pubDate>1232271232</pubDate>
           <guid>4972f780-a6f8-4445-a49e-6ae7439f3c61</guid>
       </item>
       <item>
           <title>Freezing v02 c07[kmts-NCIS]</title>
           <link>http://crazymanga.be/Manga/242</link>
           <description>Freezing v02 c07[kmts-NCIS]</description>
           <pubDate>1232225865</pubDate>
           <guid>49724649-dca8-444c-994e-2efd439f3c61</guid>
       </item>
       <item>
           <title>Akumetsu v09c73[att-inr-md]</title>
           <link>http://crazymanga.be/Manga/294</link>
           <description>Akumetsu v09c73[att-inr-md]</description>
           <pubDate>1232192402</pubDate>
           <guid>4971c392-36bc-44e4-aedf-74ab439f3c61</guid>
       </item>
       <item>
           <title>To Love-Ru c132[RH]</title>
           <link>http://crazymanga.be/Manga/65</link>
           <description>To Love-Ru c132[RH]</description>
           <pubDate>1232178581</pubDate>
           <guid>49718d95-04e8-414a-a695-58e2439f3c61</guid>
       </item>
       <item>
           <title>Bakuman ch21[SleepyFans]</title>
           <link>http://crazymanga.be/Manga/48a0a4b6-f300-4e54-a7d8-530d425a6735</link>
           <description>Bakuman ch21[SleepyFans]</description>
           <pubDate>1232167771</pubDate>
           <guid>4971635b-bd14-4c33-8a8c-4be2439f3c61</guid>
       </item>
       <item>
           <title>Mysterious Girlfriend X chapter 30 [tktranslate]</title>
           <link>http://crazymanga.be/Manga/70</link>
           <description>Mysterious Girlfriend X chapter 30
[tktranslate]</description>
           <pubDate>1232167749</pubDate>
           <guid>49716345-3994-4267-8805-4ded439f3c61</guid>
       </item>
       <item>
           <title>Buster Keel v01 ch4[SIN]</title>
           <link>http://crazymanga.be/Manga/4904c191-6278-4168-a442-113b425a6735</link>
           <description>Buster Keel v01 ch4[SIN]</description>
           <pubDate>1232151010</pubDate>
           <guid>497121e2-eee4-43db-ae7e-36c1439f3c61</guid>
       </item>
       <item>
           <title>Ojiichan wa Shounen Tantei v04 c23[Desudesu]</title>
           <link>http://crazymanga.be/Manga/488778fa-f32c-4cbb-a224-4421425a6735</link>
           <description>Ojiichan wa Shounen Tantei v04
c23[Desudesu]</description>
           <pubDate>1232125908</pubDate>
           <guid>4970bfd4-5e54-40c6-9dc4-2898439f3c61</guid>
       </item>
       <item>
           <title>Kami to Sengoku Seitokai v03 c017[FH]</title>
           <link>http://crazymanga.be/Manga/190</link>
           <description>Kami to Sengoku Seitokai v03 c017[FH]</description>
           <pubDate>1232104901</pubDate>
           <guid>49706dc5-949c-4a03-8be1-6714439f3c61</guid>
       </item>
       <item>
           <title>Girls Saurus DX v07 c46[Solaris-SVU]</title>
           <link>http://crazymanga.be/Manga/43</link>
           <description>Girls Saurus DX v07 c46[Solaris-SVU]</description>
           <pubDate>1232081582</pubDate>
           <guid>497012ae-5390-49d4-bf12-2ab4439f3c61</guid>
       </item>
       <item>
           <title>Bartender v02c12[DATS]</title>
           <link>http://crazymanga.be/Manga/493fdc23-9e74-4ef5-a5e5-3550425a6735</link>
           <description>Bartender v02c12[DATS]</description>
           <pubDate>1232057936</pubDate>
           <guid>496fb650-e820-49af-9a00-12a4439f3c61</guid>
       </item>
</channel>
</rss>

-------------------------------------------------------------------------------

Firstly, I tried checking both pages with Opera's Validate button. The
SPIP output supposedly passes minimal W3C but not be properly identified
for full validation. The second output actually failed in several places
AND it could not be identified by the validator, but it's been working in
Opera without any issues.

Did you say that this issue has been occurring with other SPIP-derived
feeds? If so then possibly the code above may prove helpful to someone who
works with feed sources.

My personal suspicion is that the generator method is throwing Opera for a
loop. The browser is designed to permanently store new entries until they
are manually deleted. It is possible (but unlikely) that Opera's feed
preview display is generated from the same caching mechanism.

I have hundreds of stored, generated entries from crazymanga.be with no
duplicates. The same number of entries shows up in Firefox as it does in
Opera. There are no extra or duplicate entries in the output of
latest/rss, which means that Opera either freshly generates the list from
site sources, or filters cached entries that do not meet the cutoff.

Hmmm.... crazymanga.be uses pubDate to indicate when an entry was created.
The free.fr feed uses dc:date and several other dc: commands. Possibly
Opera cannot comprehend the dc:date tag and therefore must use other means
to determine the age of an entry? And since SPIP sites *sometimes*
generate a page and *sometimes* pull it from their cache, this may be
confusing Opera even more.

In short it would be best for compatibility's sake if free.fr's SPIP
parsers had a better template for generating feed data. An RSS 2.0 feed
does not contain references to a dead website's RSS 1.0 documentation.
Firefox is PARTIALLY capable of handling this format (as it shows a valid
publication date, same as it does for crazymanga.be's output), but it is
NOT able to show what free.fr is trying to display.

Illustration.

--------------------------
  <item>
    <title>Fabrique planaire, fabrique linéaire</title>
    <link>Free.fr - Pages personnelles: Trop de slots demandes;
    <guid
isPermaLink="true">Free.fr - Pages personnelles: Trop de slots demandes;
    <dc:date>2009-01-16T12:26:31Z</dc:date>
    <dc:format>text/html</dc:format>
    <dc:language>fr</dc:language>
    <dc:creator>Jeff</dc:creator>

<description>Foliation, linéation et différentes
géométries de déformation ductile.

-
<a href="Free.fr - Pages personnelles: Trop de slots demandes;
rel="directory">033. Photos géologiques</a>

</description>

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/L-S.jpg" length="204085"
type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0785.jpg"
length="176561" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0790.jpg"
length="135590" type="image/jpeg" />

    <enclosure
url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0802-Canada08_IMG_0805.jpg"
length="656766" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0806.jpg"
length="153352" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0811.jpg"
length="148526" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0820.jpg"
length="153788" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0822.jpg"
length="154348" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0825.jpg"
length="153615" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_0869.jpg"
length="177298" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_1134.jpg"
length="117332" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_Canada08_IMG_1140.jpg"
length="134860" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/TN_IMG_9655.jpg"
length="141407" type="image/jpeg" />

    <enclosure url="http://jfmoyen.free.fr/IMG/jpg/pli_en_fourreau.jpg"
length="64033" type="image/jpeg" />

  </item>
-----------------------------
Note how many "enclosure" tags there are? A series of embedded pictures.
Firefox shows one entry from that list. Internet Explorer 7 shows one
entry. Opera shows none. I do not know what free.fr is hoping to
accomplish, but the only browser on my computer that can process their
feed, is Safari. SAFARI. The Safari Web Browser is able to chew through
their mess and turn it into a meaningful display. This may indicate that
webkit-type Google Chrome may also work, but I do not currently have a
working install of that. If you must have feed output you'll have to put
up with a non-Opera program.

Shameless plug: my.opera provides 1GB of storage, and feeds by RSS 2.0,
Atom 1.0, or an automatically generated widget.

--
Using Opera's revolutionary e-mail client: http://www.opera.com/mail/