On Fri, Aug 23, 2013 at 7:06 AM, Sumana Harihareswara &lt;sumanah(a)wikimedia.org > On 08/01/2013 03:08 AM, Jiang BIAN &lt;bianjiang(a)google.com> > Hi, > > > > I noticed some pages we crawled containing error message like this; > > > > <div id="mw-content-text" lang="zh-CN" dir="ltr" > class="mw-content-ltr"><p > > class="error">Failed to render property P373: > > Wikibase\LanguageWithConversion::factory: given languages do not have the > > same parent language</p> > > > > > > But when I open the url in browser, there is no such message. And using > > index.php can also get normal content without error messages. > > > > Here are examples you can retry: > > > > bad > > $ wget 'http://zh.wikipedia.org/zh-cn/Google' > > > > good > > $ wget 'http://zh.wikipedia.org/w/index.php?title=Google' > > > > > > Looks like something is wrong on Wikipedia side, anything need to fix? > > > > > > > > Thanks > > I checked with Jiang Bian and found out that this is still happening -- > can anyone help Google out here? :-) > > -- > Sumana Harihareswara > Engineering Community Manager > Wikimedia Foundation > > _______________________________________________ > Wikitech-l mailing list > Wikitech-l(a)lists.wikimedia.org > https://lists.wikimedia.org/mailman/listinfo/wikitech-l > There was a bug in some Wikibase version deployed in July which caused this error, but a fix was backported soon and since then I've never seen any similar error as a logged in user. If you still see some errors only when unlogged in at particular URLs (like what you described) now, it's likely that those URLs got cached in Squid when the bug was live... In this case purging those pages[1] should be able to fix the issue. [1] https://en.wikipedia.org/wiki/Wikipedia:Purge -Liangent

On Fri, Aug 23, 2013 at 8:13 AM, Jiang BIAN &lt;bianjiang(a)google.com&gt; wrote: I can't think of a good way to fix the problem from this aspect besides waiting for old cached page to expire, unless some sysadmin is happy to nuke all existing Squid cached pages. However if you have a list of affected pages as you're crawling HTML, which we don't have, you can simply purge them in batch and recrawl those pages. There was no bug created in bugzilla... I submitted a patch[1] directly to fix the bug once it was spotted. [1] https://gerrit.wikimedia.org/r/#/c/76060/ -Liangent

On Fri, Aug 23, 2013 at 8:33 AM, Jiang BIAN &lt;bianjiang(a)google.com&gt; wrote: This is the root cause of that behavior you mentioned. (It only happens / happened on zhwiki and maybe as well as some wikis with variants, right?) -Liangent