Re: PHP 4.0 Bug #8017: PHP ignores "If-Modified-Since" headers

Hello again, Header("Status: 304 Not Modified") does not work for me. All that did was add a "Status" header to the regular 200 response: HTTP/1.1 200 OK Date: Wed, 29 Nov 2000 03:41:12 GMT Server: Apache/1.3.14 (Unix) PHP/4.0.3pl1 X-Powered-By: PHP/4.0.3pl1 Status: 304 Not Modified Connection: close Content-Type: text/html which obviously isn't the desired effect.. Again, I still think PHP should automatically handle If-Modified-Since itself, by sending back a 304 response code and no content if the PHP script sends out a Modified header which is less than or equal to If-Modified-Since. As I've said, CGI scripts written in non-web languages such as Perl or sh do this automatically (i.e. with *no* special coding at all), so IMHO it only stands to reason that a high-level language like PHP should too. Jordan Russell ----- Original Message ----- From: "Frank M. Kromann" <fmk@swwwing.com> To: "Jordan Russell" <jr@quo.to> Cc: <php-dev@lists.php.net> Sent: Tuesday, November 28, 2000 9:19 PM Subject: Re: [PHP-DEV] PHP 4.0 Bug #8017: PHP ignores "If-Modified-Since" headers > Hi Jordan, > > The ETAG is returned in $HTTP_IF_NONE_MATCH and id send Header("Status: 304 Not Modified"); to the browser and terminates the script with an exit command if data is not modified. That works fo me. > This will also work if the browser is configured to check for new versions on every visit. I might mention that we also uses header to set expiredate back in time to force the browser to check on every visit, no mater the browser settings. > > If the webserver did cache the page, how would you get new content displayed in the situation where the script was untouched but data was modified in the database. I still dont see this as a bug. > > - Frank > > >Hi, > > > >I understand that I could use an ETAG or manually parse the > >If-Modified-Since header myself, but it seems like PHP should handle > >If-Modified-Since itself. After all, a very simple shell script like the one > >I posted below handles it properly (i.e. returns 304 codes), and "sh" isn't > >even designed for HTTP like PHP is! It is for that reason I filed this issue > >as a bug report. > > > >If I have no other choice but to manually send back a 304 code myself, what > >is the proper way to do it? I tried: > > > >Header ("HTTP/1.0 304 Not Modified"); > > > >but that sent back a 304 code which included a Content-Type header -- a > >violation of the HTTP spec. (HTTP says 304 responses "must be returned > >without any message-body".) > > > >Jordan Russell > > > >----- Original Message ----- > >From: "Frank M. Kromann" <fmk@swwwing.com> > >To: <jr-php@quo.to> > >Cc: <php-dev@lists.php.net> > >Sent: Tuesday, November 28, 2000 8:42 PM > >Subject: Re: [PHP-DEV] PHP 4.0 Bug #8017: PHP ignores "If-Modified-Since" > >headers > > > > > >> Hi All, > >> > >> I use "Last-Modified" and an ETAG header with my php scripts. I use the > >ETAG header to check if data has been modified in the database, if not I > >have the php script return a HTTP 304 header alowing the browser to use the > >page from cache. > >> This works fine for me. > >> > >> I dont think anye webserver would be able to detect this for all php > >scrpts and keep the contents in cache (dynamic web pages does not exist on > >the harddisk). > >> > >> - Frank > >> > >> >From: jr-php@quo.to > >> >Operating system: Linux > >> >PHP version: 4.0.3pl1 > >> >PHP Bug Type: Apache related > >> >Bug description: PHP ignores "If-Modified-Since" headers > >> > > >> >PHP: 4.0.3p1 > >> >Apache: 1.3.14 > >> >Browser: IE 5.5 SP1 > >> > > >> >Because I want my PHP pages to be cached, my PHP script sends out a > >Last-Modified header (entire code follows): > >> > > >> ><?php > >> >Header ("Last-Modified: Mon, 27 Nov 2000 00:00:00 GMT"); > >> >?> > >> >Test... > >> > > >> >One would think that this would be enough to get a web browser to cache > >the page, but evidently it is not. Examining my web server's access log > >shows that each time the page is subsequently requested (e.g. by pressing > >Refresh), it sends back a "200 OK" response code instead of a "304 Not > >Modified" as it should. In other words, the server is sending back a fresh > >copy of the page every time. > >> > > >> >However, if I do a similar thing using a CGI script, the server *does* > >send back "304" codes as it should (entire code follows): > >> > > >> >#!/bin/sh > >> >echo "Last-Modified: Mon, 27 Nov 2000 00:00:00 GMT" > >> >echo "Content-Type: text/html" > >> >echo "" > >> >echo "Test..." > >> > > >> >In both cases, an "If-Modified-Since" header is being sent to the server. > >Yet the PHP script appears to ignore it completely and send a fresh page, > >while the very simple CGI shell script doesn't. > >> > > >> >P.S. At the bottom of this are transcripts of the HTTP requests for the > >PHP & CGI scripts. Notice how PHP sends back a fresh page even though the > >If-Modified-Since date is the same as the Last-Modified date. > >> > > >> >P.P.S. I just noticed that this problem affects PHP's own web site too! > >The page http://www.php.net/ returns a Last-Modified > >header, but browsers > >receive a fresh copy of the page every time since If-Modified-Since is > >ignored. > >> > > >> > > >> >--- PHP script --- > >> > > >> >GET /test.php HTTP/1.0 > >> >If-Modified-Since: Mon, 27 Nov 2000 00:00:00 GMT > >> > > >> >HTTP/1.1 200 OK > >> >Date: Mon, 27 Nov 2000 20:41:29 GMT > >> >Server: Apache/1.3.14 (Unix) PHP/4.0.3pl1 > >> >X-Powered-By: PHP/4.0.3pl1 > >> >Last-Modified: Mon, 27 Nov 2000 00:00:00 GMT > >> >Connection: close > >> >Content-Type: text/html > >> > > >> >Test... > >> > > >> > > >> >--- CGI shell script --- > >> > > >> >GET /cgi-bin/test.cgi HTTP/1.0 > >> >If-Modified-Since: Mon, 27 Nov 2000 00:00:00 GMT > >> > > >> >HTTP/1.1 304 Not Modified > >> >Date: Mon, 27 Nov 2000 20:41:46 GMT > >> >Server: Apache/1.3.14 (Unix) PHP/4.0.3pl1 > >> >Connection: close > >> > > >> > > >> >-- > >> >Edit Bug report at: > >> >http://bugs.php.net/?id=8017&edit=1 > >> > > >> > > >> > > >> >-- > >> >PHP Development Mailing List > >> ><http://www.php.net/> > >> >To unsubscribe, e-mail: php-dev-unsubscribe@lists.php.net > >> >For additional commands, e-mail: php-dev-help@lists.php.net > >> >To contact the list administrators, e-mail: php-list-admin@lists.php.net > >> > > >> > > >> > > >> > >> > >> > > > > > > > > > > > -- > PHP Development Mailing List <http://www.php.net/> > To unsubscribe, e-mail: php-dev-unsubscribe@lists.php.net > For additional commands, e-mail: php-dev-help@lists.php.net > To contact the list administrators, e-mail: php-list-admin@lists.php.net >