Re: Proxying PHP Pages

On Fri, 11 Dec 1998, Steve Judge wrote:

> 2) Dynamic PHP pages, are these the same as cgi's and should we include
> them under the stoplist part not to cache or fetch from neighbors etc ?

PHP (www.php.net) is like any other dynamic page creation tool - that is,
there is the possibility of page output changing between requests (same for
any CGI tool, embedded Perl, Cold Fusion, ASP, whatever).

That having been said, however, there is also the possibility of the page
output NOT changing between requests received over a certain period - that is,
that a certain object data is identical for a given request URL until some
period of time has expired.

Like anything, it's up to the Web author to properly publish their expiration
policies in the HTTP headers (not just for proxies, but also browsers).

For example, on an Apache Web server with the Expires module included, a PHP
document includes no "Last-Modified", "Expires" or "Cache-control" header.

You can, however, include these headers in the output of your PHP (or other
dynamic - yes, even CGI) script (as we've done on some of our PHP pages).

> I've also emailed the company concerned suggesting that their product
> should be more proxy aware as they are a fact of life on the internet now
> instead of adding isp's to a ban list that are running " aggressive
> cacheing practices " as they put it.

Agreed.

> >I'm writing from Digital Addiction, a game company. Our game, Sanctum, is
> >played over the Internet.
> >One of our players uses Globec as her Internet Service Provider. She has
> >problems accessing our registration-required web pages because of your
> >company's cacheing practices.
> >We believe that your aggressive cacheing practices do not respect our
> >dynamic PHP web pages as dynamic.

Observations:

- I think I've found a few PHP pages on their site (in the absence of
  example URLs), and no headers are produced (as commented above).

- I thought we had fairly aggressive caching practices; for example:

  #hierarchy_stoplist cgi-bin ? -- (ie., default, nothing uncommented)
  #no_cache -- nothing
  refresh_pattern . 1440 200% 43200

- Either the clients know to do the right thing, or I'm missing something
  entirely because each time I request a page (say, /account/store.html)
  I'm seeing "TCP_MISS ... DIRECT/www.digitaladdiction.com"

I take the "/account/store.html" page to be a PHP script based on some
comments in the page's output, and also the fact that the form therein refers
back to the same URL (ie., the page is self-referential).

> >Our shared customer consistently gets expired cookies. Can you recommend a
> >solution? We do not want to include Globec on our list of ISPs
> >that are incompatible with our game. I hope we can find a way for our
> shared >customer to continue her relationship with both companies.

Cheers..

dave
Received on Fri Dec 11 1998 - 04:41:10 MST