Bug 23314 – Twitter Javascript Rendering

• Status: RESOLVED
• Resolution: FIXED
• Component: Evangelism

[Anthony Robertson]

zensmile.com has a javascript Twitter feed on the site. The javascript loads and renders the first time the site is visited, but does not render on any subsequent refreshes or visits until the browser app is quit and the user returns to the site.

[Mark Rowe (bdash)]

<rdar://problem/6496828>

[Deirdre Saoirse Moen]

Is this a regression?

[Henrik Blomqvist]

This is certainly odd. I haven't noticed it until now. I also have a twitter-feed on my website (www.henkeblomqvist.se) but just today I noticed this issue. 

[Mark Rowe (bdash)]

*** Bug 24265 has been marked as a duplicate of this bug. ***

[Mark Rowe (bdash)]

Bug 24265 has a reduction of this.

[Cameron Zwarich (cpst)]

Created attachment 28157 [details]
Reduction

Here's the reduction from the other bug. The JS alert should always display something, but when you reload it doesn't.

[Cameron Zwarich (cpst)]

This bug goes away if you disable caches. I'll include some of the headers from the web inspector.

With caches disabled:

Accept:*/*
Cache-Control:max-age=0
User-Agent:Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_6; en-us) AppleWebKit/528.16 (KHTML, like Gecko) Version/4.0 Safari/528.16

First time with caches enabled:

Accept:*/*
User-Agent:Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_6; en-us) AppleWebKit/528.16 (KHTML, like Gecko) Version/4.0 Safari/528.16

If this is done after loading the page with caches disabled and renabling, the Cache-Control header also appears.

Reload with caches enabled:

Accept:*/*
Cache-Control:max-age=0
If-Modified-Since:Mon, 02 Mar 2009 00:37:10 GMT
If-None-Match:"6671b9bb98042a4a52d541a3ce1da4d6"-gzip
User-Agent:Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_6; en-us) AppleWebKit/528.16 (KHTML, like Gecko) Version/4.0 Safari/528.16

I am not sure if these are all of the headers, because of bug 24272. I'll play around with Curl to see if any of these headers are confusing Twitter's server.

[Cameron Zwarich (cpst)]

The problem here is with Twitter. This returns a JS callback with no data:

curl "http://twitter.com/statuses/user_timeline/webkit.json?callback=twitterCallback2&count=5" -H "If-Modified-Since:Mon, 02 Mar 2009 00:37:10 GMT"

However, this returns data:

curl "http://twitter.com/statuses/user_timeline/webkit.json?callback=twitterCallback2&count=5"

If you change the date in the If-Modified-Since to the distant past, it also returns data. The problem seems to be that the HTTP headers are being handled by something that just returns a chunk of data that is put in the JS callback. When there is no new data, they should be giving a 304.

[Cameron Zwarich (cpst)]

I have filed a bug with Twitter's ticket system. I will still mark this an evangelism bug. If I don't have any success, perhaps Apple's evangelism people will.

[Cameron Zwarich (cpst)]

This has been fixed by Twitter:

http://apiwiki.twitter.com/REST-API-Changelog

See the April 8th entry there.