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Accepted
Sam
Asked: 2010-12-05 11:01:08 +0800 CST

How to rewrite query strings in url (\img?src=foo.jpg) into cachable urls (\img-foo.jpg)?

  • 772

a question that is now partially resolved. A genius who can speak Apache fluently can shine light into this matter...

GIVEN: Most proxies, do not cache resources with a "?" in their URL even if a Cache-control: public header is present in the response. To enable proxy caching for these resources, i have to remove query strings from references to static resources, and instead encode the parameters into the file names themselves.*

CURRENTLY HAVE

 <img src="/imgcpu?src=folder1/photo_citty.jpg&w=3500&h=10&c=p&q=90" />
 <img src="/imgcpu?src=folder2/photo_doggy.jpg&w=100&h=200&c=p" />
 <img src="/imgcpu?src=folder3/photo_birds.jpg&w=200&h=500&f=bw" />
 <img src="/imgcpu?src=folder3/photo_frogs.jpg&w=200&f=bw" />

WOULD LIKE

 <img src="/IMG-folder1/photo_citty.jpg_w3500_h10_cp_q90" />
 <img src="/IMG-folder2/photo_doggy.jpg_w100_h200_cp" />
 <img src="/IMG-folder3/photo_birds.jpg_w200_h500_cs_fbw" />
 <img src="/IMG-folder3/photo_frogs.jpg_w200_fbw" />
  • The images will reside in 1 folder deep on the root (never deeper)
  • the img.php?src= or img?src= will be consistently named this forever

I know the "img?src=" is a bad part and have already handled with that:

# Rewrite imgcpu?src= thumbnail maker to nice static urls
RewriteRule ^IMG-(.*) /imgcpu?src=$1 [L]

But the rest im stuck at. any and all clues are greatly welcome. Thanks.

PROGRESS
IMG-folder1/photo_citty.jpg&w=3500&h=10&c=p&q=90 WORKS
IMG-folder1/photo_citty.jpg_w-3500_h-10_c-p_q-90 DOESNT WORK
IMG-folder1/photo_citty_w-3500_h-10_c-p_q-90.jpg DOESNT WORK 

RewriteRule ^IMG-(.+)_w-(.+)_h-(.+)_c-(.+)$ imgcpu\?src=$1&w=$2&h=$3&c=$4 [L]
RewriteRule ^IMG-(.+)_w-(.+)_h-(.+)_f-(.+)$ imgcpu\?src=$1&w=$2&h=$3&f=$4 [L]   
RewriteRule ^IMG-(.+)_w-(.+)_h-(.+)$ imgcpu\?src=$1&w=$2&h=$3 [L]
RewriteRule ^IMG-(.+)_w-(.+)$ imgcpu\?src=$1&w=$2 [L]
RewriteRule ^IMG-(.+)_h-(.+)$ imgcpu\?src=$1&h=$3 [L]
# pfff endless possibilities!!

And this doesnt even cover the cases where first the height is given the width. No this shall not work!

Lets find a solution to redirect all OPTIONAL &w= or &h= with something like &[a-z]=(.*) sothat _h- or _w- are universal and doesnt matter what letter is there _c- or _q- anything could then fit. THAT would be a very welcome rewrite.

Meanwhile this does works!! 

<img src"/IMG-folder/photo_w100_h100_cf_q60.jpg"/>

by using:

RewriteRule ^IMG-(.+)_w(.+)_h(.+)_c(.+)_q(.+).jpg$ 
            imgcpu\?src=$1\.jpg&w=$2&h=$3&c=$4&q=$5 [L]

So the assignment Now is:
Rewrite any or all of the queries that follow [photo123.jpg]&[a-z]=(.*)&[a-z]=(.*)etcettera into photo123_X-x_Y-y(optionally more queries).jpg

php apache-2.2 rewrite mod-rewrite query

2 Answers

  1. Best Answer

    The rule

    RewriteRule ^/imgcpu\?src=(.+)&w=(.+)&h=(.+)&c=(.+)&q=(.+)$ /IMG-$1_w-$2_h-$3_c-$4_q-$5

    Will deal with the first case, the problem is that you would need a much more complex RE to deal with the differences on the second and third line (missing q and p parts of the url, extra s variable, etc).

    To prevent the mess of a long and write-only regular expression I would make one different rule for each of the three cases.

    • 1 
  2. RewriteRule ^IMG-(.+)_w-(.+)_h-(.+)_c-(.+)$ imgcpu\?src=$1&w=$2&h=$3&c=$4 [L]
RewriteRule ^IMG-(.+)_w-(.+)_h-(.+)_f-(.+)$ imgcpu\?src=$1&w=$2&h=$3&f=$4 [L]   
RewriteRule ^IMG-(.+)_w-(.+)_h-(.+)$ imgcpu\?src=$1&w=$2&h=$3 [L]
RewriteRule ^IMG-(.+)_w-(.+)$ imgcpu\?src=$1&w=$2 [L]
RewriteRule ^IMG-(.+)_h-(.+)$ imgcpu\?src=$1&h=$3 [L]
# pfff endless possibilities!!

    And this doesnt even cover the cases where first the height is given the width. No this shall not work!

    Lets find a solution to redirect all OPTIONAL &w= or &h= with something like &[a-z]=(.*) sothat _h- or _w- are universal and doesnt matter what letter is there _c- or _q- anything could then fit. THAT would be a very welcome rewrite.

    Meanwhile this does works!! 

    <img src"/IMG-folder/photo_w100_h100_cf_q60.jpg"/>

    by using:

    RewriteRule ^IMG-(.+)_w(.+)_h(.+)_c(.+)_q(.+).jpg$ 
            imgcpu\?src=$1\.jpg&w=$2&h=$3&c=$4&q=$5 [L]

    So the assignment Now is:
    Rewrite any or all of the queries that follow [photo123.jpg]&[a-z]=(.*)&[a-z]=(.*)etcettera into photo123_X-x_Y-y(optionally more queries).jpg

    • 0