Ordering of query string parameters

[Poul-Henning Kamp]

In message <BANLkTi=b12PEvHxgu2PBtTBTb8kVY8wsfg at mail.gmail.com>, Daniel Sell wr
ites:

>For example, these two URLs result in the same content:
>
>/index.php?a=1&b=2
>/index.php?b=2&a=1
>
>The URL generation is out of my control, and there are many possible
>parameters.
>
>As far as I can tell, Varnish will generate different hashes for these two
>URLs.  Is there anything I can do?

If you know the parameters are from a finite set, you can rewrite
vcl_hash to do them one at a time in a specific order:

	hash_data (the url)
	hash_data (param 'a')
	hash_data (param 'b')
	hash_data (param 'c')

A Vmod which sorts the params alphabetically might be a good idea if
this is a general problem

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