RE: Setting Content-Type in a custom response (mp2)

Torsten Förtsch wrote on 2010-03-11:
> On Thursday 11 March 2010 15:18:08 Steve Hay wrote:
>> I have a mod_perl-2 handler that uses custom_response() to display
>> error messages if something goes wrong:
>> 
>> $r->custom_response(Apache2::Const::SERVER_ERROR, $error);
>> return Apache2::Const::SERVER_ERROR;
>> 
>> That almost works fine, but the trouble is that the Content-Type header
>> is always set to "text/html; charset=iso-8859-1", in which the charset,
>> at least, is potentially wrong: all the pages in my software produce
>> UTF-8 and are normally output with Content-Type "application/xhtml+xml;
>> charset=utf-8".
>> 
>> How do I set the Content-Type when issuing a custom_reponse()? The
>> usual thing of calling
>> 
>> $r->content_type("application/xhtml+xml; charset=utf-8");
>> 
>> doesn't seem to work in this case.
>> 
> I think that is impossible. ap_send_error_response() contains this code:
> 
>         if (apr_table_get(r->subprocess_env,
>                           "suppress-error-charset") != NULL) {
>             core_request_config *request_conf =
>                         ap_get_module_config(r->request_config,
> &core_module);
>             request_conf->suppress_charset = 1; /* avoid adding default
>                                                  * charset later
>                                                  */
>             ap_set_content_type(r, "text/html");
>         }
>         else {
>             ap_set_content_type(r, "text/html; charset=iso-8859-1");
>         }
>  The resulting content-type is either "text/html; charset=iso-8859-1" or
> "text/html".
> 
> But instead of passing the response text directly to $r-
>> custom_response you
> can specify an URL. ap_die() will then create an internal redirect to
> this URL. Via $r->prev->pnotes you can then access the pnotes of the
> failed request. Putting all together a solution could look like:
> 
>   $r->pnotes->{estring}=$error;
>   $r->pnotes->{ect}='my/special-content-type'; # use an otherwise not
>   used URL here $r->custom_response(Apache2::Const::SERVER_ERROR,
>   '/-/error');
>   
>   <Location /-/error>
>     SetHandler modperl
>     # please insert a \ at the end of each of the following lines
>     # up to }"
>     PerlResponseHandler "sub {
>       my ($r)=@_; return Apache2::Const::NOT_FOUND unless $r->prev;
>       $r->content_type($r->prev->pnotes->{ect});
>       $r->print($r->prev->pnotes->{estring}); return Apache2::Const::OK;
>     }"
>   </Location>
> 

Thanks! That works a treat :-)