rat/lonambiguous.pm - view

File: [LON-CAPA] / rat / lonambiguous.pm
Revision 1.2: download - view: text, annotated - select for diffs
Thu Oct 12 14:54:08 2000 UTC (23 years, 6 months ago) by www
Branches: MAIN
CVS tags: HEAD

Now does multiple choice for ambiguous situations

1: # The LearningOnline Network with CAPA 2: # Handler to resolve ambiguous file locations 3: # 4: # (TeX Content Handler 5: # 6: # 05/29/00,05/30,10/11 Gerd Kortemeyer) 7: # 8: # 10/11,10/12 Gerd Kortemeyer 9: 10: package Apache::lonambiguous; 11: 12: use strict; 13: use Apache::lonnet; 14: use Apache::Constants qw(:common REDIRECT); 15: use GDBM_File; 16: 17: 18: # ----------------------------------------------------------- Could not resolve 19: 20: sub getlost { 21: my ($r,$errmsg)=@_; 22: $r->content_type('text/html'); 23: $r->send_http_header; 24: $r->print( 25: '<head><title>Unknown Error</title></head><body bgcolor="#FFFFFF"><h1>'. 26: 'LON-CAPA</h1>Could not handle ambiguous resource reference.<p>'.$errmsg. 27: '</body></html>'); 28: } 29: 30: # ================================================================ Main Handler 31: 32: sub handler { 33: my $r=shift; 34: 35: if ($r->header_only) { 36: $r->content_type('text/html'); 37: $r->send_http_header; 38: return OK; 39: } 40: 41: # ---------------------------------------------------------- Is this selecting? 42: 43: my %bighash; 44: 45: if ($ENV{'form.selecturl'}) { 46: my $envkey; 47: if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db', 48: &GDBM_READER,0640)) { 49: foreach $envkey (keys %ENV) { 50: if ($envkey=~/^form\.(\d+)\.(\d+)$/) { 51: my $mapid=$1; 52: my $resid=$2; 53: my $resurl=$bighash{'src_'.$mapid.'.'.$resid}; 54: &Apache::lonnet::symblist($bighash{'map_id_'.$mapid}, 55: $resurl => $resid); 56: $r->header_out(Location => 57: 'http://'.$ENV{'HTTP_HOST'}.$resurl); 58: return REDIRECT; 59: } 60: } 61: untie(%bighash); 62: # ---------------------------------------------------- Update symb and redirect 63: } else { 64: &getlost($r,'Could not access course structure.'); 65: return OK; 66: } 67: } 68: 69: # ---------------------------------------------------------- Do we have a case? 70: 71: my $thisfn; 72: unless (($thisfn=$ENV{'request.ambiguous'})&&($ENV{'request.course.fn'})) { 73: &getlost($r,'Could not find information on resource.'); 74: return OK; 75: } 76: 77: # ---------------------------------- Should this file have been part of a page? 78: 79: $thisfn=&Apache::lonnet::declutter($thisfn); 80: my %hash; 81: my $syval=''; 82: 83: if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'_symb.db', 84: &GDBM_READER,0640)) { 85: $syval=$hash{$thisfn}; 86: untie(%hash); 87: } 88: 89: # ---------------------------------------------------------- There was an entry 90: 91: if ($syval) { 92: 93: if ($syval=~/\_$/) { 94: # ----------------------------------- Okay, this should have appeared on a page 95: $syval=~s/\_\_\_$//; 96: $r->content_type('text/html'); 97: $r->header_out(Location => 98: 'http://'.$ENV{'HTTP_HOST'}.'/res/'.$syval); 99: return REDIRECT; 100: } else { 101: # There is not really a problem (???), but cannot go back without endless loop 102: &getlost($r,'The nature of the problem is unclear'); 103: return OK; 104: } 105: } 106: 107: # ------------------------------------------------ Would be standalone resource 108: 109: if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db', 110: &GDBM_READER,0640)) { 111: # ---------------------------------------------- Get ID(s) for current resource 112: my $ids=$bighash{'ids_/res/'.$thisfn}; 113: if ($ids) { 114: # ------------------------------------------------------------------- Has ID(s) 115: my @possibilities=split(/\,/,$ids); 116: my $couldbe=''; 117: map { 118: if (&Apache::lonnet::allowed('bre',$bighash{'src_'.$_})) { 119: if ($couldbe) { 120: $couldbe.=','.$_; 121: } else { 122: $couldbe=$_; 123: } 124: } 125: } @possibilities; 126: if ($couldbe) { 127: @possibilities=split(/\,/,$couldbe); 128: if ($#possibilities>0) { 129: # ----------------------------------------------- Okay, really multiple choices 130: $r->content_type('text/html'); 131: $r->send_http_header; 132: $r->print(<<ENDSTART); 133: <head><title>Choose Location</title></head> 134: <body bgcolor="#FFFFFF"> 135: <h1>LON-CAPA</h1> 136: The resource you had been accessing appears more than once in this course, 137: and LON-CAPA has insufficient session information to determine which instance 138: of the resource you meant. 139: <p> 140: Please click on the instance of the resource you intended to access: 141: <p> 142: <form action="/adm/ambiguous" method=post> 143: <input type=hidden name=orgurl value="$thisfn"> 144: <input type=hidden name=selecturl value=1> 145: <table border=2> 146: <tr><th> </th><th>Title</th><th>Type</th><th>Part of ...</th></tr> 147: ENDSTART 148: map { 149: my $mapurl=$bighash{'map_id_'.(split(/\./,$_))[0]}; 150: $r->print('<tr><td><input type=submit value=Select name="'. 151: $_.'"></td><td>'.$bighash{'title_'.$_}. 152: '</td><td>'.$bighash{'type_'.$_}. 153: '</td><td><a href="'.$mapurl.'">'.$mapurl. 154: '</a></td></tr>'); 155: } @possibilities; 156: $r->print('</table></form></body></html>'); 157: untie(%bighash); 158: return OK; 159: } 160: } 161: } 162: untie(%bighash); 163: } 164: 165: # ------------------------------------ This handler should not have been called 166: &getlost($r,'Invalid call of handler'); 167: return OK; 168: } 169: 170: 1; 171: __END__ 172: 173: 174: 175: 176: 177: 178: