# The LearningOnline Network with CAPA # # Sequence Handler # # (Handler to resolve ambiguous file locations # # (TeX Content Handler # # 05/29/00,05/30,10/11 Gerd Kortemeyer) # # 10/11,10/12 Gerd Kortemeyer) # # 10/16 Gerd Kortemeyer package Apache::lonsequence; use strict; use Apache::lonnet; use Apache::Constants qw(:common :http REDIRECT); use GDBM_File; # ----------------------------------------------------------- Could not resolve sub getlost { my ($r,$errmsg)=@_; $r->content_type('text/html'); $r->send_http_header; $r->print( 'Unknown Error

'. 'LON-CAPA

Could not handle sequence resource reference.

'.$errmsg. ''); } # ================================================================ Main Handler sub handler { my $r=shift; if ($r->header_only) { $r->content_type('text/html'); $r->send_http_header; return OK; } my %hash; my %bighash; my $requrl=$r->uri; # ------------------------------------------------------------ Tie symb db file if ($ENV{'request.course.fn'}) { my $last; if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'_symb.db', &GDBM_READER,0640)) { $last=$hash{'last_direction'}; untie(%hash); } my $direction=''; my $prevmap=''; if ($last) { ($prevmap,$direction)=(split(/\_\_\_/,$last)); } # ------------------------------------------------------------- Tie big db file if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db', &GDBM_READER,0640)) { my $disid=''; my $whatend=''; if ($direction eq 'back') { $disid=$bighash{'map_finish_'.$requrl}; $whatend='End'; } else { $disid=$bighash{'map_start_'.$requrl}; $whatend='Beginning'; } my $disurl=''; my $dismapid=''; if ($disid) { $disurl=$bighash{'src_'.$disid}; $dismapid=(split(/\./,$disid))[1]; } my $symb=''; my $sequencetitle=''; unless($disurl) { if ($symb=&Apache::lonnet::symbread()) { my ($mapurl,$mapid)=split(/\_\_\_/,$symb); $sequencetitle=$bighash{'title_'. $bighash{'map_pc_/res/'.$mapurl}.'.'. $mapid}; } } # --------------------------------------- Untie hash, make sure to come by here untie(%bighash); if ($disurl) { # -------------------------------------------------- Has first or last resource &Apache::lonnet::symblist($requrl,$disurl => $dismapid, 'last_known' => &Apache::lonnet::declutter($disurl)); $r->content_type('text/html'); $r->header_out(Location => 'http://'.$ENV{'HTTP_HOST'}.$disurl); return REDIRECT; } else { # ---------- Does not have first or last resource, try to find out where we are unless ($symb) { $r->internal_redirect('/adm/ambiguous'); } $r->content_type('text/html'); $r->send_http_header; $r->print(<

$whatend of

$sequencetitle

ENDSYMB return OK } } else { &getlost($r,'Could not access course structure.'); return OK; } } else { $ENV{'user.error.msg'}="$requrl:bre:0:0:Course not initialized"; return HTTP_NOT_ACCEPTABLE; } return OK; } 1; __END__ 500 Internal Server Error

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator at root@localhost to inform them of the time this error occurred, and the actions you performed just before this error.

More information about this error may be available in the server error log.