HTTP Compression for Flash XML

HTTP Compression works so transparently that even some of the most technically aware folks that I've know haven't known of it. Some files are highly compressible, HTML, TXT and XML are sometimes reduce to only 10% of their original size. Webservers will often (with mod_gzip) compress files before sending them out and browsers will automatically unzip them when received. That's an ideal solution when CPU cycles (for compression) are plentiful and bandwidth (for sending) is scarce.

Some files are already compressed - like .gif, .jpg, often .swf files - and these would make bad candidates for further compression, so the webserver has a list of file extensions that it typically applies compression to. Inexplicably, often this does not include .xml files. Check with your hosting provider. Alternatively, rename the files with a .txt or .htm extension to guarantee the benefits of HTTP Compression on your large XML files.

Posted by Alexander at February 14, 2005 10:44 AM

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HTTP compression is neat as soon as you could deal with it client side.
My provider use HTTP compression for all the .xml files.
But Flash is unable to decompress natively text file.
Moreover, Flash report a false weight for that compressed file. Than, try to preload…

So it's a goodie in theory, but an headache in practice.
(I had bad time to figure out what happen when my provider didn't communicate about this """feature""")


Posted by: erixtekila at February 14, 2005 11:36 AM

Yes, the preloader status can be awkward, but I'd rather spend one second looking at a preloader that didn't work than ten seconds looking at one that does.

I just checked with my current hosting company
and they use HTTP Compression on XML by default. I switched the file extension to .jpg and a 70K document took a lot longer to arrive.

I think what's going on is that most XML that is being sent is being compressed, but many people aren't aware of this and fret needlessly about 'XML Bloat'.

Posted by: Alexander McCabe at February 14, 2005 03:27 PM