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Up to [LON-CAPA] / loncom / interface

- Bug 6754 LON-CAPA as LTI Consumer
  - Missing : in URLs for retrieval of roster from LTI Consumer, and
    passback of grades to LTI Consumer.
  - Correct secret used to make signature for ext_ims_lis_memberships_id

    1: # The LearningOnline Network with CAPA
    2: # Launch External Tool Provider (LTI)
    3: #
    4: # $Id: lonexttool.pm,v 1.8 2017/12/06 02:15:35 raeburn Exp $
    5: #
    6: # Copyright Michigan State University Board of Trustees
    7: #
    8: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
    9: #
   10: # LON-CAPA is free software; you can redistribute it and/or modify
   11: # it under the terms of the GNU General Public License as published by
   12: # the Free Software Foundation; either version 2 of the License, or
   13: # (at your option) any later version.
   14: #
   15: # LON-CAPA is distributed in the hope that it will be useful,
   16: # but WITHOUT ANY WARRANTY; without even the implied warranty of
   17: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   18: # GNU General Public License for more details.
   19: #
   20: # You should have received a copy of the GNU General Public License
   21: # along with LON-CAPA; if not, write to the Free Software
   22: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   23: #
   24: # /home/httpd/html/adm/gpl.txt
   25: #
   26: # http://www.lon-capa.org/
   27: #
   28: 
   29: =pod
   30: 
   31: =head1 NAME
   32: 
   33: Apache::lonexttool - Tool Provider launcher
   34: 
   35: =head1 SYNOPSIS
   36: 
   37: 
   38: =head1 OVERVIEW
   39: 
   40: =cut
   41: 
   42: package Apache::lonexttool;
   43: 
   44: use strict;
   45: use Apache::Constants qw(:common :http);
   46: use Net::OAuth;
   47: use Encode;
   48: use Digest::SHA;
   49: use UUID::Tiny ':std';
   50: use HTML::Entities;
   51: use Apache::lonlocal;
   52: use Apache::lonnet;
   53: use Apache::loncommon;
   54: 
   55: sub handler {
   56:     my $r=shift;
   57:     &Apache::loncommon::content_type($r,'text/html');
   58:     $r->send_http_header;
   59: 
   60:     return OK if $r->header_only;
   61: 
   62:     my $target=$env{'form.grade_target'};
   63: # ------------------------------------------------------------ Print the screen
   64:     if ($target eq 'tex') {
   65:         $r->print(&Apache::lonprintout::print_latex_header($env{'form.latex_type'}));
   66:     }
   67: 
   68: # Is this even in a course?
   69:     unless ($env{'request.course.id'}) {
   70:         if ($target ne 'tex') {
   71:             &Apache::loncommon::simple_error_page($r,'','Not in a course');
   72:         } else {
   73:             $r->print('\textbf{Not in a course}\end{document}');
   74:         }
   75:         return OK;
   76:     }
   77: 
   78:     my ($marker,$exttool) = (split(m{/},$r->uri))[4,5];
   79:     $marker=~s/\D//g;
   80: 
   81:     if (!$marker) {
   82:         if ($target ne 'tex') {
   83:             $r->print(&mt('Invalid Call'));
   84:         } else {
   85:             $r->print('\textbf{'&mt('Invalid Call').'}\end{document}');
   86:         }
   87:         return OK;
   88:     }
   89: 
   90:     my $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
   91:     my $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
   92:     my $chome = $env{'course.'.$env{'request.course.id'}.'.home'};
   93:     my $is_tool;
   94: 
   95:     if ($r->uri eq "/adm/$cdom/$cnum/$marker/$exttool") {
   96:         my %toolsettings=&Apache::lonnet::dump('exttool_'.$marker,$cdom,$cnum);
   97:         if ($toolsettings{'id'}) {
   98:             my $idx = $toolsettings{'id'};
   99:             my %ltitools = &Apache::lonnet::get_domain_lti($cdom,'consumer');
  100:             if (ref($ltitools{$idx}) eq 'HASH') {
  101:                 my %toolhash = %{$ltitools{$idx}}; 
  102:                 $toolhash{'display'} = {
  103:                                            target => $toolsettings{'target'},
  104:                                            width  => $toolsettings{'width'},
  105:                                            height => $toolsettings{'height'},
  106:                                        };
  107:                 $toolhash{'crslabel'} = $toolsettings{'crslabel'};
  108:                 $toolhash{'crstitle'} = $toolsettings{'crstitle'};
  109:                 $toolhash{'crsappend'} = $toolsettings{'crsappend'};
  110:                 $is_tool = 1;
  111:                 my $launchok = 1;
  112:                 if ($target eq 'tex') {
  113:                     $r->print(&mt('External Tool'));
  114:                 } else {
  115:                     my $now = time;
  116:                     if ($toolhash{'passback'}) {
  117:                         unless (&set_callback_secret($cdom,$cnum,$marker,'grade',$now,
  118:                                                      \%toolsettings,\%toolhash) eq 'ok') {
  119:                             undef($launchok);
  120:                         }
  121:                     }
  122:                     if ($toolhash{'roster'}) {
  123:                         &set_callback_secret($cdom,$cnum,$marker,'roster',$now,
  124:                                              \%toolsettings,\%toolhash);
  125:                     }
  126:                     my $submittext = &mt('Launch [_1]',$toolhash{'title'});
  127:                     if (($toolhash{'key'} ne '') && ($toolhash{'secret'} ne '') && 
  128:                         ($toolhash{'url'} ne '') && ($launchok)) {
  129:                         my %lti = &lti_params($r,$cnum,$cdom,$idx,$submittext,\%toolhash);
  130:                         my $url = $toolhash{'url'};
  131:                         if ($toolhash{'crsappend'} ne '') {
  132:                             $url .= $toolhash{'crsappend'};
  133:                         }
  134:                         $r->print(&launch_html($url,$toolhash{'key'},$toolhash{'secret'},
  135:                                                $submittext,\%lti));
  136:                     } else {
  137:                         $r->print('<div>'.&mt('External Tool Unavailable').'</div>');
  138:                     }
  139:                 }
  140:             }
  141:         }
  142:     }
  143:     unless ($is_tool) {
  144:         if ($target ne 'tex') {
  145:             $r->print('<div>'.&mt('Invalid Call').'</div>');
  146:         } else {
  147:             $r->print('\textbf{'.&mt(Invalid Call).'}\end{document}');
  148:         }
  149:     }
  150:     return OK;
  151: }
  152: 
  153: sub set_callback_secret {
  154:     my ($cdom,$cnum,$marker,$name,$now,$toolsettings,$toolhash) = @_;
  155:     return unless ((ref($toolsettings) eq 'HASH') && (ref($toolhash) eq 'HASH'));
  156:     my $warning;
  157:     my ($needsnew,$oldsecret,$lifetime);
  158:     if ($name eq 'grade') {  
  159:         $lifetime = $toolhash->{'passbackvalid'}
  160:     } elsif ($name eq 'roster') {
  161:         $lifetime = $toolhash->{'rostervalid'};
  162:     }  
  163:     if ($toolsettings->{$name} eq '') {
  164:         $needsnew = 1;
  165:     } elsif (($toolsettings->{$name.'date'} + $lifetime) < $now) {
  166:         $oldsecret = $toolsettings->{$name.'secret'};
  167:         $needsnew = 1;
  168:     }
  169:     if ($needsnew) {
  170:         if (&get_tool_lock($cdom,$cnum,$marker,$now) eq 'ok') {
  171:             my $secret = UUID::Tiny::create_uuid_as_string(UUID_V4);
  172:             $toolhash->{$name.'secret'} = $secret;
  173:             my %secrethash = (
  174:                            $name.'secret' => $secret,
  175:                            $name.'secretdate' => $now,
  176:                           );
  177:             if ($oldsecret ne '') {
  178:                 $secrethash{'old'.$name.'secret'} = $oldsecret;
  179:             }
  180:             my $putres = &Apache::lonnet::put('exttool_'.$marker,
  181:                                               \%secrethash,$cdom,$cnum);
  182:             my $delresult = &release_tool_lock($cdom,$cnum,$marker);
  183:             if ($delresult ne 'ok') {
  184:                 $warning = $delresult ;
  185:             }
  186:             if ($putres eq 'ok') {
  187:                 return 'ok';
  188:             }
  189:         } else {
  190:             $warning = '<span class="LC_error">'.
  191:                        &mt('Could not obtain exclusive lock').
  192:                        '</span>';
  193:         }
  194:     } else {
  195:         $toolhash->{$name.'secret'} = $toolsettings->{$name.'secret'};
  196:         return 'ok';
  197:     }
  198:     return;
  199: }
  200: 
  201: sub lti_params {
  202:     my ($r,$cnum,$cdom,$idx,$submittext,$toolsref) = @_;
  203:     my ($version,$context_type,$msgtype,$toolname,$passback,$roster,$locale,
  204:         $crslabel,$crstitle,$gradesecret,$rostersecret,%fields,%rolesmap,
  205:         %display,%custom,@userlangs);
  206:     if (ref($toolsref) eq 'HASH') {
  207:         $version = $toolsref->{'version'};
  208:         $toolname = $toolsref->{'title'};
  209:         $passback = $toolsref->{'passback'};
  210:         $gradesecret = $toolsref->{'gradesecret'};
  211:         $roster = $toolsref->{'roster'};
  212:         $rostersecret = $toolsref->{'rostersecret'};
  213:         $msgtype = $toolsref->{'messagetype'};
  214:         if (ref($toolsref->{'fields'}) eq 'HASH') {
  215:             %fields = %{$toolsref->{'fields'}};
  216:         }
  217:         if (ref($toolsref->{'roles'}) eq 'HASH') {
  218:             %rolesmap = %{$toolsref->{'roles'}};
  219:         }
  220:         if (ref($toolsref->{'display'}) eq 'HASH') {
  221:             %display = %{$toolsref->{'display'}};
  222:         }
  223:         if (ref($toolsref->{'custom'}) eq 'HASH') {
  224:             %custom = %{$toolsref->{'custom'}};
  225:         }
  226:         $crslabel = $toolsref->{'crslabel'};
  227:         $crstitle = $toolsref->{'crstitle'};
  228:     }
  229:     if ($version eq '') {
  230:         $version = 'LTI-1p0';
  231:     }
  232:     if ($context_type eq '') {
  233:         $context_type = 'CourseSection';
  234:     }
  235:     if ($msgtype eq '') {
  236:         $msgtype = 'basic-lti-launch-request';
  237:     }
  238:     if ($crslabel eq '') {
  239:         $crslabel = $env{'course.'.$env{'request.course.id'}.'.internal.coursecode'},
  240:     }
  241:     if ($crstitle eq '') {
  242:         $crstitle = $env{'course.'.$env{'request.course.id'}.'.description'},;
  243:     }
  244:     my $lonhost = $r->dir_config('lonHostID');
  245:     my $loncaparev = $r->dir_config('lonVersion');
  246:     my $uname = $env{'user.name'};
  247:     my $udom = $env{'user.domain'};
  248:     my @possroles = qw(Instructor ContentDeveloper TeachingAssistant Learner);
  249:     my ($roleprefix) = ($env{'request.role'} =~ /^(\w+)\./);
  250:     my $ltirole = $rolesmap{$roleprefix};
  251:     unless (grep(/^\Q$ltirole\E$/,@possroles)) {
  252:         $ltirole = 'Learner';
  253:     }
  254:     my $digest_user = &Encode::decode_utf8($uname.':'.$udom);
  255:     $digest_user = &Digest::SHA::sha1_hex($digest_user);
  256:     if ($env{'course.'.$env{'request.course.id'}.'.languages'} ne '') {
  257:         @userlangs=(@userlangs,split(/\s*(\,|\;|\:)\s*/,
  258:                     $env{'course.'.$env{'request.course.id'}.'.languages'}));
  259:     } else {
  260:         my %langhash = &Apache::loncommon::getlangs($uname,$udom);
  261:         if ($langhash{'languages'} ne '') {
  262:             @userlangs = split(/\s*(\,|\;|\:)\s*/,$langhash{'languages'});
  263:         } else {
  264:             my %domdefs = &Apache::lonnet::get_domain_defaults($udom);
  265:             if ($domdefs{'lang_def'} ne '') {
  266:                 @userlangs = ($domdefs{'lang_def'});
  267:             }
  268:         }
  269:     }
  270:     if (scalar(@userlangs) == 1) {
  271:         $locale = $userlangs[0];
  272:     }
  273:     my ($title,$digest_symb);
  274:     my ($symb) = &Apache::lonnet::whichuser();
  275:     if ($symb) {
  276:         $digest_symb = &Encode::decode_utf8($symb);
  277:         $digest_symb = &Digest::SHA::sha1_hex($digest_symb);
  278:         my $navmap = Apache::lonnavmaps::navmap->new();
  279:         if (ref($navmap)) {
  280:             my $res = $navmap->getBySymb($symb);
  281:             if (ref($res)) {
  282:                 $title = $res->compTitle();
  283:             }
  284:         }
  285:     }
  286:     my $domdesc = &Apache::lonnet::domain($cdom);
  287:     my $primary_id = &Apache::lonnet::domain($cdom,'primary');
  288:     my $int_dom = &Apache::lonnet::internet_dom($primary_id);
  289:     my $portal_url = &Apache::lonnet::course_portal_url($cnum,$cdom);
  290: 
  291:     my %ltiparams = (
  292:         lti_version                            => $version,
  293:         lti_message_type                       => $msgtype,
  294:         resource_link_title                    => $title,
  295:         resource_link_id                       => $digest_symb,
  296:         tool_consumer_instance_guid            => $lonhost,
  297:         tool_consumer_instance_description     => $domdesc,
  298:         tool_consumer_info_product_family_code => 'loncapa',
  299:         tool_consumer_instance_name            => $int_dom,  
  300:         tool_consumer_instance_url             => $portal_url,
  301:         tool_consumer_info_version             => $loncaparev,
  302:         user_id                                => $digest_user,
  303:         roles                                  => $ltirole,
  304:         context_id                             => $env{'request.course.id'},
  305:         context_type                           => $context_type,
  306:         context_label                          => $crslabel,
  307:         context_title                          => $crstitle,
  308:         launch_presentation_locale             => $locale,
  309:     );
  310:     my $crshome = $env{'course.'.$env{'request.course.id'}.'.home'};
  311:     my $crshostname = &Apache::lonnet::hostname($crshome);
  312:     if ($crshostname) {
  313:         my $crsprotocol = $Apache::lonnet::protocol{$crshome};
  314:         unless ($crsprotocol eq 'https') {
  315:             $crsprotocol = 'http';
  316:         }
  317:         if (($passback) || ($roster)) {
  318:             if ($passback) {
  319:                 $ltiparams{'lis_outcome_service_url'} = $crsprotocol.'://'.$crshostname.'/adm/service/passback';
  320:                 $ltiparams{'ext_ims_lis_basic_outcome_url'} = $ltiparams{'lis_outcome_service_url'};
  321:                 if ($gradesecret) {
  322:                     my $result_sig = 
  323:                         Digest::SHA::sha1_hex($gradesecret.':::'.$digest_symb.':::'.$digest_user.':::'.$env{'request.course.id'});
  324:                     $ltiparams{'lis_result_sourcedid'} =
  325:                         $result_sig.':::'.$digest_symb.':::'.$digest_user.':::'.$env{'request.course.id'};
  326:                 }
  327:             }
  328:             if ($roster) {
  329:                 if (&Apache::lonnet::allowed('opa',$env{'request.course.id'})) {
  330:                     $ltiparams{'ext_ims_lis_memberships_url'} = $crsprotocol.'://'.$crshostname.'/adm/service/roster';
  331:                     if ($rostersecret) {
  332:                         my $roster_sig = Digest::SHA::sha1_hex($rostersecret.':::'.$digest_symb.':::'.$env{'request.course.id'});
  333:                         $ltiparams{'ext_ims_lis_memberships_id'} = $roster_sig.':::'.$digest_symb.':::'.$env{'request.course.id'};
  334:                     }
  335:                 }
  336:             }
  337:             my %digesthash;
  338:             if ($ltiparams{'lis_result_sourcedid'}) {
  339:                 $digesthash{$ltiparams{'lis_result_sourcedid'}} = "$idx\0".time; 
  340:             }
  341:             if ($ltiparams{'ext_ims_lis_memberships_id'}) {
  342:                 $digesthash{$ltiparams{'ext_ims_lis_memberships_id'}} = "$idx\0".time; 
  343:             }
  344:             if (($digest_symb) && ($gradesecret || $rostersecret)) {
  345:                 $digesthash{$digest_symb} = $symb;
  346:             }
  347:             if (($passback) && ($gradesecret)) {
  348:                 $digesthash{$digest_user} = $uname.':'.$udom;
  349:             }
  350:             if (keys(%digesthash)) {
  351:                 &Apache::lonnet::put('exttools',\%digesthash,$cdom,$cnum);
  352:             }
  353:         }
  354:     }
  355:     if ($display{'target'}) {
  356:         $ltiparams{'launch_presentation_document_target'} = $display{'target'};
  357:     }
  358:     if ($display{'width'}) {
  359:         $ltiparams{'launch_presentation_width'} = $display{'width'};
  360:     }
  361:     if ($display{'height'}) {
  362:         $ltiparams{'launch_presentation_height'} = $display{'height'};
  363:     }
  364:     if ($fields{'firstname'}) {
  365:         $ltiparams{'lis_person_name_given'} = $env{'environment.firstname'};
  366:     }
  367:     if ($fields{'lastname'}) {
  368:         $ltiparams{'lis_person_name_family'} = $env{'environment.lastname'};
  369:     }
  370:     if ($fields{'fullname'}) {
  371:         $ltiparams{'lis_person_name_full'} = &Apache::loncommon::plainname($uname,$udom);
  372:     }
  373:     if ($fields{'email'}) {
  374:         my %emails = &Apache::loncommon::getemails($uname,$udom);
  375:         my $contact_email;
  376:         foreach my $type ('permanentemail','critnotification','notification') {
  377:             if ($emails{$type} =~ /\@/) {
  378:                 $contact_email = $emails{$type};
  379:                 last;
  380:             }
  381:         }
  382:         $ltiparams{'lis_person_contact_email_primary'} = $contact_email;
  383:     }
  384:     if ($fields{'user'}) {
  385:         $ltiparams{'lis_person_sourcedid'} = $uname.':'.$udom;
  386:     }
  387:     if (keys(%custom)) {
  388:         foreach my $key (keys(%custom)) {
  389:             my $value = $custom{$key};
  390:             $value =~ s/^\s+|\s+\$//g;
  391:             if ($value =~ /^\QLONCAPA::env{\E([^\}]+)\}$/) {
  392:                 if (exists($env{$1})) {
  393:                     $value = $env{$1};
  394:                 }
  395:             }
  396:             $ltiparams{'custom_'.$key} = $value;
  397:         }
  398:     }
  399:     foreach my $key (keys(%ltiparams)) {
  400:         $ltiparams{$key} = &Encode::decode_utf8($ltiparams{$key});
  401:     }
  402:     $ltiparams{'basiclti_submit'} = $submittext;
  403:     return %ltiparams;
  404: }
  405: 
  406: sub launch_html {
  407:     my ($url,$key,$secret,$submittext,$paramsref) = @_;
  408:     my $hashref = &sign_params($url,$key,$secret,$paramsref);
  409:     my $action = &HTML::Entities::encode($url,'<>&"');
  410:     my $form = <<"END";
  411: <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
  412: <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
  413: <body>
  414: <div id="LCltiLaunch">
  415: <form name="LCltiLaunchForm" id="LCltiLaunchFormId" action="$action" method="post" encType="application/x-www-form-urlencoded">
  416: END
  417:     if (ref($hashref) eq 'HASH') {
  418:         foreach my $item (keys(%{$hashref})) {
  419:             my $type = 'hidden';
  420:             if ($item eq 'basiclti_submit') {
  421:                 $type = 'submit';
  422:             }
  423:             $form .= '<input type="'.$type.'" name="'.$item.'" value="'.$hashref->{$item}.'" id="id_'.$item.'" />'."\n";
  424:         }
  425:     }
  426:     $form .= "</form></div>\n";
  427:     $form .= <<"ENDJS";
  428: <script type="text/javascript">
  429:     document.getElementById("LCltiLaunch").style.display = "none";
  430:     nei = document.createElement('input');
  431:     nei.setAttribute('type','hidden');
  432:     nei.setAttribute('name','basiclti_submit');
  433:     nei.setAttribute('value','$submittext');
  434:     document.getElementById("LCltiLaunchFormId").appendChild(nei);
  435:     document.LCltiLaunchForm.submit();
  436:  </script>
  437: ENDJS
  438:     $form .= "</body></html>\n";
  439:     return $form;
  440: }
  441: 
  442: sub sign_params {
  443:     my ($url,$key,$secret,$paramsref) = @_;
  444:     my $nonce = Digest::SHA::sha1_hex(sprintf("%06x%06x",rand(0xfffff0),rand(0xfffff0)));
  445: 
  446:     my $request = Net::OAuth->request("request token")->new(
  447:             consumer_key => $key,
  448:             consumer_secret => $secret,
  449:             request_url => $url,
  450:             request_method => 'POST',
  451:             signature_method => 'HMAC-SHA1',
  452:             timestamp => time,
  453:             nonce => $nonce,
  454:             callback => 'about:blank',
  455:             extra_params => $paramsref,
  456:             version      => '1.0',
  457:             );
  458:     $request->sign;
  459:     return $request->to_hash();
  460: }
  461: 
  462: sub get_tool_lock {
  463:     my ($cdom,$cnum,$marker,$now) = @_;
  464:     # get lock for tool for which gradesecret is being set
  465:     my $lockhash = {
  466:                   $marker."\0".'lock' => $now.':'.$env{'user.name'}.
  467:                                          ':'.$env{'user.domain'},
  468:                    };
  469:     my $tries = 0;
  470:     my $gotlock = &Apache::lonnet::newput('exttools',$lockhash,$cdom,$cnum);
  471: 
  472:     while (($gotlock ne 'ok') && $tries <3) {
  473:         $tries ++;
  474:         sleep(1);
  475:         $gotlock = &Apache::lonnet::newput('exttools',$lockhash,$cdom,$cnum);
  476:     }
  477:     return $gotlock;
  478: }
  479: 
  480: sub release_tool_lock {
  481:     my ($cdom,$cnum,$marker) = @_;
  482:     #  remove lock
  483:     my @del_lock = ($marker."\0".'lock');
  484:     my $dellockoutcome=&Apache::lonnet::del('exttools',\@del_lock,$cdom,$cnum);
  485:     if ($dellockoutcome ne 'ok') {
  486:         return ('<div class="LC_error">'
  487:                .&mt('Warning: failed to release lock for exttool: [_1].','<tt>'.$marker.'</tt>')
  488:                .'</div>'
  489:                );
  490:     } else {
  491:         return 'ok';
  492:     }
  493: }
  494: 
  495: 1;