Re: Q & A: $r->custom_response
At 22:04 23.04.2002, Perrin Harkins wrote: >Per Einar Ellefsen wrote: >>I suppose Apache::Constants could have been extended to return globals if >>requested... But is there really any gain in that? > >Only in that people will not get tripped up by the possible bugs that >using subroutines as constants causes. I guess Apache::Constants is >difficult to replace, so everyone will just have to keep an eye out for >this sort of problem. Agreed. I'll add a warning in the docs for Apache::Constants which might help out in the future. -- Per Einar Ellefsen [EMAIL PROTECTED]
Re: Q & A: $r->custom_response
Per Einar Ellefsen wrote: > I suppose Apache::Constants could have been extended to return globals > if requested... But is there really any gain in that? Only in that people will not get tripped up by the possible bugs that using subroutines as constants causes. I guess Apache::Constants is difficult to replace, so everyone will just have to keep an eye out for this sort of problem. - Perrin
Re: Q & A: $r->custom_response
At 19:51 23.04.2002, Perrin Harkins wrote:
>Per Einar Ellefsen wrote:
>>Well, this one is exported by Apache::Constants, so if you don't want to do
>>$FORBIDDEN = FORBIDDEN;
>>somewhere at the top of your code, you're bound to continue using
>>constants, right?
>
>That's still safer. I used the constants pragma on a big project and I
>saw people get bitten by $hash{CONSTANT} and "string interp CONSTANT" as
>well as the aforementioned CONSTANT => value problem. It's just asking
>for trouble, in my opinion.
>
>Can anyone tell us if the Apache::Constants all just standard HTTP
>response codes, or are some of them actually Apache-specific?
Apache::Constants gets them from httpd.h. Here is the expert:
#define HTTP_CONTINUE 100
#define HTTP_SWITCHING_PROTOCOLS 101
#define HTTP_PROCESSING102
#define HTTP_OK200
#define HTTP_CREATED 201
#define HTTP_ACCEPTED 202
#define HTTP_NON_AUTHORITATIVE 203
#define HTTP_NO_CONTENT204
#define HTTP_RESET_CONTENT 205
#define HTTP_PARTIAL_CONTENT 206
#define HTTP_MULTI_STATUS 207
#define HTTP_MULTIPLE_CHOICES 300
#define HTTP_MOVED_PERMANENTLY 301
#define HTTP_MOVED_TEMPORARILY 302
#define HTTP_SEE_OTHER 303
#define HTTP_NOT_MODIFIED 304
#define HTTP_USE_PROXY 305
#define HTTP_TEMPORARY_REDIRECT307
#define HTTP_BAD_REQUEST 400
#define HTTP_UNAUTHORIZED 401
#define HTTP_PAYMENT_REQUIRED 402
#define HTTP_FORBIDDEN 403
#define HTTP_NOT_FOUND 404
#define HTTP_METHOD_NOT_ALLOWED405
#define HTTP_NOT_ACCEPTABLE406
#define HTTP_PROXY_AUTHENTICATION_REQUIRED 407
#define HTTP_REQUEST_TIME_OUT 408
#define HTTP_CONFLICT 409
#define HTTP_GONE 410
#define HTTP_LENGTH_REQUIRED 411
#define HTTP_PRECONDITION_FAILED 412
#define HTTP_REQUEST_ENTITY_TOO_LARGE 413
#define HTTP_REQUEST_URI_TOO_LARGE 414
#define HTTP_UNSUPPORTED_MEDIA_TYPE415
#define HTTP_RANGE_NOT_SATISFIABLE 416
#define HTTP_EXPECTATION_FAILED417
#define HTTP_UNPROCESSABLE_ENTITY 422
#define HTTP_LOCKED423
#define HTTP_FAILED_DEPENDENCY 424
#define HTTP_INTERNAL_SERVER_ERROR 500
#define HTTP_NOT_IMPLEMENTED 501
#define HTTP_BAD_GATEWAY 502
#define HTTP_SERVICE_UNAVAILABLE 503
#define HTTP_GATEWAY_TIME_OUT 504
#define HTTP_VERSION_NOT_SUPPORTED 505
#define HTTP_VARIANT_ALSO_VARIES 506
#define HTTP_INSUFFICIENT_STORAGE 507
#define HTTP_NOT_EXTENDED 510
#define DOCUMENT_FOLLOWSHTTP_OK
#define PARTIAL_CONTENT HTTP_PARTIAL_CONTENT
#define MULTIPLE_CHOICESHTTP_MULTIPLE_CHOICES
#define MOVED HTTP_MOVED_PERMANENTLY
#define REDIRECTHTTP_MOVED_TEMPORARILY
#define USE_LOCAL_COPY HTTP_NOT_MODIFIED
#define BAD_REQUEST HTTP_BAD_REQUEST
#define AUTH_REQUIRED HTTP_UNAUTHORIZED
#define FORBIDDEN HTTP_FORBIDDEN
#define NOT_FOUND HTTP_NOT_FOUND
#define METHOD_NOT_ALLOWED HTTP_METHOD_NOT_ALLOWED
#define NOT_ACCEPTABLE HTTP_NOT_ACCEPTABLE
#define LENGTH_REQUIRED HTTP_LENGTH_REQUIRED
#define PRECONDITION_FAILED HTTP_PRECONDITION_FAILED
#define SERVER_ERRORHTTP_INTERNAL_SERVER_ERROR
#define NOT_IMPLEMENTED HTTP_NOT_IMPLEMENTED
#define BAD_GATEWAY HTTP_BAD_GATEWAY
#define VARIANT_ALSO_VARIES HTTP_VARIANT_ALSO_VARIES
So apparently, FORBIDDEN == HTTP_FORBIDDEN == 403.
However, I wouldn't rely on any of this, because that's the reason behind
constants: they hide what they really are!
For example, we have this:
#define DECLINED -1 /* Module declines to handle */
#define DONE -2 /* Module has served the response completely
* - it's safe to die() with no more output
*/
#define OK 0/* Module has handled this stage. */
OK should therefore not be confused with HTTP_OK (many people seem to bite
the bug and return 200, which isn't supposed to be right).
I suppose Apache::Constants could have been extended to return globals if
requested... But is there really any gain in that?
--
Per Einar Ellefsen
[EMAIL PROTECTED]
Re: Q & A: $r->custom_response
> Can anyone tell us if the Apache::Constants all just standard HTTP > response codes, or are some of them actually Apache-specific? > there are over 90 constants in Apache::Constants, which range from HTTP constants (like FORBIDDEN for 403) to Apache specific ones (like DECLINED for -1 and OPT_INCLUDES for 2). there is also stuff like SERVER_VERSION which is really a runtime call to ap_get_server_version(). --Geoff
Re: Q & A: $r->custom_response
Per Einar Ellefsen wrote:
> Well, this one is exported by Apache::Constants, so if you don't want to do
> $FORBIDDEN = FORBIDDEN;
> somewhere at the top of your code, you're bound to continue using
> constants, right?
That's still safer. I used the constants pragma on a big project and I
saw people get bitten by $hash{CONSTANT} and "string interp CONSTANT" as
well as the aforementioned CONSTANT => value problem. It's just asking
for trouble, in my opinion.
Can anyone tell us if the Apache::Constants all just standard HTTP
response codes, or are some of them actually Apache-specific?
- Perrin
Re: Q & A: $r->custom_response
At 19:38 23.04.2002, Perrin Harkins wrote: >Issac Goldstand wrote: >>Reposting a question (and the answer) that geoff and I discussed in the >>IRC room, as I think it's worthwhile to mention... >>I had the following line of code (actually many of the sort): >>$r->custom_response(FORBIDDEN=>"File size exceeds quota."); >>And kept getting errors like: >>[Tue Apr 23 19:46:14 2002] null: Argument "FORBIDDEN" isn't numeric in >>subroutine entry at /usr/local/httpd/lib/perl/Mine/Pic/Application.pm >>line 1343. >>The answer to the problem is that by using '=>' instead of ',', I was >>making 'FORBIDDEN' become '"FORBIDDEN"' (string instead of numeric 403). >>Moral of the story: don't use => with Apache::Constants! > >In fact, don't use constants at all. At least not the kind created by the >"use constants" pragma and similar tricks. They have all kinds of >problems like this. Use package variables instead ($FORBIDDEN). Maybe >some day Perl will have real constants, but I'm perfectly happy with >package variables in the meantime. Well, this one is exported by Apache::Constants, so if you don't want to do $FORBIDDEN = FORBIDDEN; somewhere at the top of your code, you're bound to continue using constants, right? -- Per Einar Ellefsen [EMAIL PROTECTED]
Re: Q & A: $r->custom_response
At 19:29 23.04.2002, Issac Goldstand wrote: >Reposting a question (and the answer) that geoff and I discussed in the >IRC room, as I think it's worthwhile to mention... > >I had the following line of code (actually many of the sort): >$r->custom_response(FORBIDDEN=>"File size exceeds quota."); > >And kept getting errors like: >[Tue Apr 23 19:46:14 2002] null: Argument "FORBIDDEN" isn't numeric in >subroutine entry at /usr/local/httpd/lib/perl/Mine/Pic/Application.pm line >1343. > >The answer to the problem is that by using '=>' instead of ',', I was >making 'FORBIDDEN' become '"FORBIDDEN"' (string instead of numeric 403). > >Moral of the story: don't use => with Apache::Constants! Or you can use &FORBIDDEN or FORBIDDEN() or +FORBIDDEN, which are another fix if you want to continue using =>. -- Per Einar Ellefsen [EMAIL PROTECTED]
Re: Q & A: $r->custom_response
Issac Goldstand wrote: > Reposting a question (and the answer) that geoff and I discussed in the > IRC room, as I think it's worthwhile to mention... > > I had the following line of code (actually many of the sort): > $r->custom_response(FORBIDDEN=>"File size exceeds quota."); > > And kept getting errors like: > [Tue Apr 23 19:46:14 2002] null: Argument "FORBIDDEN" isn't numeric in > subroutine entry at /usr/local/httpd/lib/perl/Mine/Pic/Application.pm > line 1343. > > The answer to the problem is that by using '=>' instead of ',', I was > making 'FORBIDDEN' become '"FORBIDDEN"' (string instead of numeric 403). > > Moral of the story: don't use => with Apache::Constants! In fact, don't use constants at all. At least not the kind created by the "use constants" pragma and similar tricks. They have all kinds of problems like this. Use package variables instead ($FORBIDDEN). Maybe some day Perl will have real constants, but I'm perfectly happy with package variables in the meantime. - Perrin
