--- rat/lonwrapper.pm 2008/11/20 14:38:00 1.30
+++ rat/lonwrapper.pm 2024/02/28 19:01:41 1.49.2.11.2.7
@@ -1,7 +1,7 @@
# The LearningOnline Network with CAPA
# Wrapper for external and binary files as standalone resources
#
-# $Id: lonwrapper.pm,v 1.30 2008/11/20 14:38:00 jms Exp $
+# $Id: lonwrapper.pm,v 1.49.2.11.2.7 2024/02/28 19:01:41 raeburn Exp $
#
# Copyright Michigan State University Board of Trustees
#
@@ -31,80 +31,303 @@ package Apache::lonwrapper;
use strict;
use Apache::Constants qw(:common);
-use Apache::lonnet;
-use Apache::lonxml();
use Apache::lonenc();
-use Apache::lonmenu();
+use Apache::lonnet;
+use Apache::lonlocal;
+use Apache::loncommon();
+use Apache::lonhtmlcommon();
+use Apache::lonextresedit();
+use Apache::lonexttool();
+use Apache::lonhomework();
+use Apache::lonnavmaps();
+use LONCAPA qw(:DEFAULT :match);
+use HTML::Entities();
+use Digest::MD5();
# ================================================================ Main Handler
+sub wrapper {
+ my ($r,$url,$brcrum,$absolute,$is_ext,$is_pdf,$exttool,$linktext,$explanation,
+ $title,$width,$height,$reuse,$is_supp) = @_;
-sub simple_menu {
-#
-# Producing the menu buttons
-#
- return &Apache::loncommon::start_page('Menu',undef,
- {'only_body' => 1,
- 'bgcolor' => '#FFFFFF',}).
- &Apache::lonmenu::menubuttons(1,'web',1).
- &Apache::loncommon::end_page();
-}
+ my $forcereg;
+ unless ($env{'form.folderpath'}) {
+ $forcereg = 1;
+ }
+ my %lt = &Apache::lonlocal::texthash(
+ 'noif' => 'No iframe support.',
+ 'show' => 'Show content in pop-up window',
+ );
+
+ (undef,undef,undef,undef,undef,undef,my $clientmobile) =
+ &Apache::loncommon::decode_user_agent($r);
+
+ my ($anchor,$uselink);
+ if ($is_ext) {
+ if ($env{'form.symb'}) {
+ (undef,undef,my $res) = &Apache::lonnet::decode_symb($env{'form.symb'});
+ if ($res =~ /(#[^#]+)$/) {
+ $anchor = $1;
+ }
+ } elsif ($env{'form.anchor'} ne '') {
+ $anchor = '#'.$env{'form.anchor'};
+ }
+ if (($is_ext eq 'tab') || ($is_ext eq 'window')) {
+ $uselink = 1;
+ }
+ unless (($is_pdf && $clientmobile) || $uselink) {
+ my $hostname = $r->hostname();
+ my $lonhost = $r->dir_config('lonHostID');
+ my $ip = &Apache::lonnet::get_host_ip($lonhost);
+ $uselink = &Apache::loncommon::is_nonframeable($url,$absolute,$hostname,$ip);
+ }
+ }
+ my $noiframe = &Apache::loncommon::modal_link(&HTML::Entities::encode($url.$anchor,'&<>"\''),$lt{'show'},500,400);
+ my $args = {'bgcolor' => '#FFFFFF'};
+ if ($forcereg) {
+ $args->{'force_register'} = $forcereg;
+ }
+ if (ref($brcrum) eq 'ARRAY') {
+ $args->{'bread_crumbs'} = $brcrum;
+ }
+ if ($absolute) {
+ $args->{'use_absolute'} = $absolute;
+ }
+ if ($env{'form.only_body'}) {
+ $args->{'only_body'} = $env{'form.only_body'};
+ } elsif (($is_supp) && ($env{'form.folderpath'} ne '')) {
+ $args->{'bread_crumbs_nomenu'} = 1;
+ }
-sub wrapper {
- my ($topurl,$bottomurl) = @_;
+ my ($countdown,$donemsg,$headjs);
+ if (($exttool) && (&Apache::lonnet::EXT('resource.0.gradable') =~ /^yes$/i)) {
+ $Apache::lonhomework::browse = &Apache::lonnet::allowed('bre',$url);
+ if ($env{'form.markaccess'}) {
+ my $symb=&Apache::lonnet::symbread($url);
+ my @interval=&Apache::lonnet::EXT('resource.0.interval',$symb);
+ my ($timelimit) = split(/_/,$interval[0]);
+ my $setres = &Apache::lonnet::set_first_access($interval[1],$timelimit);
+ if ($setres eq 'ok') {
+ delete($env{'form.markaccess'});
+ }
+ } elsif ($env{'form.LC_interval_done'} eq 'true') {
+ my $symb=&Apache::lonnet::symbread($url);
+ if ($symb) {
+ (my $donebuttonresult,$donemsg) = &Apache::lonhomework::zero_timer($symb);
+ undef($env{'form.LC_interval_done'});
+ undef($env{'form.LC_interval_done_proctorpass'});
+ }
+ }
+ my ($status,$result,$resource_due) =
+ &Apache::lonexttool::gradabletool_access_check();
+ undef($Apache::lonhomework::browse);
+ if ($status eq 'CAN_ANSWER') {
+ if ($resource_due) {
+ my $time_left = $resource_due - time();
+ if ($resource_due && ($time_left > 0)) {
+ $countdown ='
+'."\n".
+ &Apache::lonhtmlcommon::set_due_date($resource_due);
+ }
+ }
+ } else {
+ if ($status eq 'SHOW_ANSWER') {
+ $result = &Apache::lonexttool::display_score().
+ &Apache::lonfeedback::list_discussion('tool','OPEN');
+ }
+ return &Apache::loncommon::start_page('Menu',undef,$args).
+ $result.
+ &Apache::loncommon::end_page();
+ }
+ }
- if ($env{'browser.interface'} eq 'textual') {
#
-# ssi-based rendering for text-based interface
+# Where iframe is in use, if window.onload() executes before the custom resize function
+# has been defined (jQuery), two global javascript vars (LCnotready and LCresizedef)
+# are used to ensure document.ready() triggers a call to resize, so the iframe contents
+# do not obscure the Functions menu.
#
- return
- &Apache::loncommon::start_page('Menu',undef,
- {'bgcolor' => '#FFFFFF',
- 'force_register' => 1,
- }).
- &Apache::lonnet::ssi_body($bottomurl).
- &Apache::loncommon::end_page();
+
+ unless ($clientmobile || ($exttool eq 'window') || ($exttool eq 'tab') || $uselink) {
+ $headjs = &Apache::loncommon::iframe_wrapper_headjs();
}
+ my $startpage = &Apache::loncommon::start_page('Menu',$headjs,$args).$countdown.$donemsg;
+ my $endpage = &Apache::loncommon::end_page();
- my %layout = ('border' => 0);
- if ($env{'environment.remote'} eq 'off') {
- if ($env{'environment.icons'} eq 'iconsonly') {
- $layout{'rows'} = "100,*";
+ if (($uselink) && ($title eq '')) {
+ if ($env{'form.symb'}) {
+ $title=&Apache::lonnet::gettitle($env{'form.symb'});
+ } elsif (!$is_supp) {
+ my $symb=&Apache::lonnet::symbread($r->uri);
+ if ($symb) {
+ $title=&Apache::lonnet::gettitle($symb);
+ }
+ }
+ }
+ if ($clientmobile || ($exttool eq 'window') || ($exttool eq 'tab') ||
+ ($is_ext eq 'tab') || ($is_ext eq 'window')) {
+ my $output = $startpage;
+ if ($is_pdf) {
+ $linktext = &mt('Link to PDF (for mobile devices)');
+ $output .= &create_link($url,$anchor,$title,$linktext);
+ } elsif (($exttool eq 'window') || ($exttool eq 'tab') ||
+ ($is_ext eq 'tab') || ($is_ext eq 'window')) {
+ my $preamble;
+ if ($linktext eq '') {
+ if ($exttool) {
+ $linktext = &mt('Launch External Tool');
+ } else {
+ $linktext = &mt('Link to External Resource');
+ }
+ }
+ if ($exttool) {
+ $url = &HTML::Entities::encode($url,'"<>&');
+ } else {
+ $url = &HTML::Entities::encode($url.$anchor,'&<>"');
+ }
+ if (($exttool eq 'tab') || ($is_ext eq 'tab')) {
+ my $target;
+ if ($exttool) {
+ $target = 'LCExternalToolTab';
+ } else {
+ if ($reuse) {
+ $target = 'LCExternalResTab';
+ } else {
+ $target = '_blank';
+ }
+ if ($title ne '') {
+ $preamble = ''.$title.'
';
+ }
+ }
+ $output .= '
';
+ } else {
+ my ($target,$extlinkimg);
+ if ($exttool) {
+ $target = 'LCExternalToolPopUp';
+ } else {
+ $target = 'LCExternalResPopUp';
+ if ($title ne '') {
+ $preamble = ''.$title.'
';
+ }
+ $extlinkimg = '';
+ unless ($reuse) {
+ my $resid;
+ if ($env{'request.course.id'}) {
+ unless (($is_supp) || ($env{'form.folderpath'} =~ /^supplemental/)) {
+ my $symb=&Apache::lonnet::symbread($r->uri);
+ if ($symb) {
+ my $navmap = Apache::lonnavmaps::navmap->new();
+ if (ref($navmap)) {
+ my $res = $navmap->getBySymb($symb);
+ if (ref($res)) {
+ $resid = $res->id;
+ $resid =~ s/\./_/g;
+ }
+ }
+ }
+ }
+ }
+ if ($resid eq '') {
+ $resid = substr(Digest::MD5::md5_hex(Digest::MD5::md5_hex(time(). {}. rand(). $$)), 0, 8);
+ }
+ &js_escape(\$resid);
+ $target .= $resid;
+ }
+ }
+ $output .= <<"ENDLINK";
+
+
+ENDLINK
+ }
+ if ($exttool) {
+ if ($explanation ne '') {
+ $output .= ''.$explanation.'
';
+ }
+ if (&Apache::lonnet::EXT('resource.0.gradable')) {
+ $output .= &Apache::lonfeedback::list_discussion('tool','OPEN');
+ }
+ }
} else {
- $layout{'rows'} = "200,*";
+ if ($uselink) {
+ $linktext = &mt('Link to resource');
+ $output .= &create_link($url,$anchor,$title,$linktext);
+ } else {
+ my $dest = &HTML::Entities::encode($url.$anchor,'&<>"');
+ $output .= ''."\n".
+ '\n".
+ "
\n";
+ }
}
+ $output .= $endpage;
+ return $output;
+ } elsif ($uselink) {
+ $linktext = &mt('Link to resource');
+ return $startpage.&create_link($url,$anchor,$title,$linktext).$endpage;
} else {
- $layout{'rows'} = "1,*";
- $topurl = "/adm/rat/empty.html";
+ # javascript will position the iframe if window was resized (or zoomed)
+ my $script = &Apache::loncommon::iframe_wrapper_resizejs();
+ my $dest = &HTML::Entities::encode($url.$anchor,'&<>"');
+ return <
+
+
+ $endpage
+ENDFRAME
}
+}
- my $start_page =
- &Apache::loncommon::start_page(undef,undef,
- {'force_register' => 1,
- 'frameset' => 1,
- 'add_entries' => \%layout, });
-
- my $end_page =
- &Apache::loncommon::end_page({'frameset' => 1});
-
- foreach my $url ($topurl,$bottomurl) {
- if ($url !~ /^http:/) {
- $url = &Apache::lonenc::check_encrypt($url);
- }
- }
-#
-# frame-based rendering for graphical interface
-#
- my $result =<
-
-$end_page
-ENDDOCUMENT
-
- return $result;
+sub create_link {
+ my ($url,$anchor,$title,$linktext) = @_;
+ my $shownlink;
+ if ($title eq '') {
+ $title = $env{'form.title'};
+ if ($title eq '') {
+ unless ($env{'request.enc'}) {
+ ($title) = ($url =~ m{/([^/]+)$});
+ $title =~ s/(\?[^\?]+)$//;
+ }
+ }
+ }
+ unless ($title eq '') {
+ $shownlink = ''.$title.'
';
+ }
+ my $dest = &HTML::Entities::encode($url.$anchor,'&<>"');
+ $shownlink .= ''.$linktext.'';
+ return $shownlink;
}
sub handler {
@@ -114,42 +337,183 @@ sub handler {
return OK if $r->header_only;
- &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
- ['wrapperdisplay']);
- if ($env{'form.wrapperdisplay'} eq 'menu') {
- $r->print(&simple_menu());
- return OK;
- }
-
- my $orgurl=$r->uri;
- my $url=$orgurl;
- $orgurl.=(($orgurl=~/\?/)?'&':'?').$ENV{'QUERY_STRING'};
- $orgurl.=(($orgurl=~/\?/)?'&':'?').'wrapperdisplay=menu';
- $url=~s/^\/adm\/wrapper//;
- my $is_ext = $url =~ m|^/ext/|;
- $url=~s{^/ext/}{http://};
- $url=~s|http://https://|https://|;
- $url=~s|:|:|g;
+ my $url = $r->uri;
+ my ($is_ext,$brcrum,$absolute,$is_pdf,$exttool,$cdom,$cnum,$hostname,
+ $linktext,$explanation,$width,$height,$reuse,$is_supp);
+
+ for ($url){
+ s|^/adm/wrapper||;
+ $is_ext = $_ =~ s|^/ext/|http://|;
+ s|http://https://|https://| if ($is_ext);
+ s|:|:|g;
+ }
+
+ if ($url =~ /\.pdf$/i) {
+ $is_pdf = 1;
+ } elsif (($is_ext) && ($env{'request.course.id'})) {
+ if ($env{'course.'.$env{'request.course.id'}.'.extresource'}) {
+ (my $selected,$reuse,$width,$height) = split(/:/,$env{'course.'.$env{'request.course.id'}.'.extresource'});
+ if ($selected eq 'tab') {
+ $is_ext = 'tab';
+ $width = '';
+ $height = '';
+ } elsif ($selected eq 'window') {
+ $is_ext = 'window';
+ unless ($width =~ /^\d+$/) {
+ $width = '';
+ }
+ unless ($height =~ /^\d+$/) {
+ $height = '';
+ }
+ } else {
+ $width = '';
+ $height = '';
+ $reuse = '';
+ }
+ }
+ } elsif ($url =~ m{^/adm/($match_domain)/($match_courseid)/(\d+)/ext\.tool$}) {
+ $cdom = $1;
+ $cnum = $2;
+ my $marker = $3;
+ $exttool = 'iframe';
+ my $exttoolremote;
+ my %toolhash = &Apache::lonnet::get('exttool_'.$marker,['target','linktext','explanation','id','width','height'],
+ $cdom,$cnum);
+ if ($toolhash{'id'}) {
+ my ($idx,%ltitools);
+ if ($toolhash{'id'} =~ /^c(\d+)$/) {
+ $idx = $1;
+ %ltitools = &Apache::lonnet::get_course_lti($cnum,$cdom,'consumer');
+ } else {
+ $idx = $toolhash{'id'};
+ %ltitools = &Apache::lonnet::get_domain_lti($cdom,'consumer');
+ }
+ if (ref($ltitools{$idx}) eq 'HASH') {
+ $exttoolremote = $ltitools{$idx}{'url'};
+ }
+ }
+ if ($toolhash{'target'} eq 'window') {
+ $exttool = 'window';
+ $width = $toolhash{'width'};
+ $height = $toolhash{'height'};
+ } elsif ($toolhash{'target'} eq 'tab') {
+ $exttool = 'tab';
+ }
+ if (($exttool eq 'window') || ($exttool eq 'tab')) {
+ $linktext = $toolhash{'linktext'};
+ $explanation = $toolhash{'explanation'};
+ } elsif (($exttoolremote =~ /^http:/) && ($ENV{'SERVER_PORT'} == 443)) {
+ $exttool = 'tab';
+ }
+ }
+ if (($is_ext) || ($exttool)) {
+ &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
+ ['forceedit','register','folderpath','symb','idx','title','anchor','only_body']);
+ if (($env{'form.forceedit'}) &&
+ (&Apache::lonnet::allowed('mdc',$env{'request.course.id'})) &&
+ (($env{'form.folderpath'} =~ /^supplemental/) ||
+ ($env{'form.symb'} =~ /^uploaded/))) {
+ if ($env{'form.symb'}) {
+ (undef,undef,my $res) = &Apache::lonnet::decode_symb($env{'form.symb'});
+ if ($res =~ /(#[^#]+)$/) {
+ $url .= $1;
+ }
+ } elsif ($env{'form.folderpath'} =~ /^supplemental/) {
+ if ($env{'form.anchor'} ne '') {
+ $url .= '#'.$env{'form.anchor'};
+ }
+ $is_supp = 1;
+ }
+ my $type = 'ext';
+ if ($exttool) {
+ $type = 'tool';
+ } elsif (($url =~ /^http:/) && ($ENV{'SERVER_PORT'} == 443)) {
+ $hostname = $r->hostname();
+ }
+ $r->print(
+ &Apache::lonextresedit::display_editor($url,$env{'form.folderpath'},
+ $env{'form.symb'},
+ $env{'form.idx'},$type,$cdom,
+ $cnum,$hostname));
+ return OK;
+ } elsif ($env{'form.folderpath'} =~ /^supplemental/) {
+ my $crstype = &Apache::loncommon::course_type();
+ my $title = $env{'form.title'};
+ if ($title eq '') {
+ if ($is_ext) {
+ $title = &mt('External Resource');
+ } else {
+ $title = &mt('External Tool');
+ }
+ }
+ $title = &HTML::Entities::encode($title,'\'"<>&');
+ $is_supp = 1;
+ if ($env{'request.course.id'}) {
+ $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
+ $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
+ &Apache::loncommon::validate_folderpath(1,'',$cnum,$cdom);
+ }
+ unless ($env{'form.only_body'}) {
+ $brcrum =
+ &Apache::lonhtmlcommon::docs_breadcrumbs(undef,$crstype,undef,$title,1);
+ }
+ }
+ } elsif ($env{'request.course.id'}) {
+ my $courseurl = &Apache::lonnet::courseid_to_courseurl($env{'request.course.id'});
+ $courseurl =~ s{^/}{};
+ if ($url =~ m{^\Q/uploaded/$courseurl/supplemental/\E}) {
+ $is_supp = 1;
+ &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
+ ['folderpath','title','only_body']);
+ if ($env{'form.folderpath'}) {
+ $cnum = $env{'course.'.$env{'request.course.id'}.'.num'};
+ $cdom = $env{'course.'.$env{'request.course.id'}.'.domain'};
+ &Apache::loncommon::validate_folderpath(1,'',$cnum,$cdom);
+ }
+ my $title = $env{'form.title'};
+ $title = &HTML::Entities::encode($title,'\'"<>&');
+ my $crstype = &Apache::loncommon::course_type();
+ unless ($env{'form.only_body'}) {
+ $brcrum =
+ &Apache::lonhtmlcommon::docs_breadcrumbs(undef,$crstype,undef,$title,1);
+ }
+ }
+ }
+
#
# Actual URL
#
- if ($url=~/\.(problem|exam|quiz|assess|survey|form|library)$/) {
+ if (($url=~/$LONCAPA::assess_re/) && (!$exttool)) {
#
# This is uploaded homework
#
- $env{'request.state'}='uploaded';
- &Apache::lonhomework::renderpage($r,$url);
+ $env{'request.state'}='uploaded';
+ &Apache::lonhomework::renderpage($r,$url);
} else {
#
# This is not homework
#
- if ($is_ext) {
- $ENV{'QUERY_STRING'}=~s/(^|\&)symb=[^\&]*/$1/;
- }
- $url.=(($url=~/\?/)?'&':'?').$ENV{'QUERY_STRING'};
- # reappend the query arguments
- $r->print(&wrapper($orgurl,$url));
+ if (($is_ext) || ($exttool)) {
+ $absolute = $env{'request.use_absolute'};
+ $ENV{'QUERY_STRING'} =~ s/(^|\&)symb=[^\&]*/$1/;
+ $ENV{'QUERY_STRING'} =~ s/\&$//;
+ }
+
+ unless ($ENV{'QUERY_STRING'} eq '') {
+ $url.=(($url=~/\?/)?'&':'?').$ENV{'QUERY_STRING'};
+ }
+
+ # encrypt url if not external
+ unless ($is_ext) {
+ &Apache::lonenc::check_encrypt(\$url);
+ }
+
+ $r->print( wrapper($r,$url,$brcrum,$absolute,$is_ext,$is_pdf,$exttool,
+ $linktext,$explanation,undef,$width,$height,$reuse,
+ $is_supp) );
+
} # not just the menu
+
return OK;
} # handler
@@ -173,19 +537,133 @@ described at http://www.lon-capa.org.
=over
-=item simple_menu()
+=item wrapper($r,$url,$brcrum,$absolute,$is_ext,$is_pdf,$exttool,$linktext,$explanation,$title,$width,$height,$reuse,$is_supp)
-=item wrapper()
+=over
-=item handler()
+=item $r
-=back
+request object
-=cut
+=item $url
+
+url to display either by including in an iframe within a
+LON-CAPA page which has a standard LON-CAPA inline menu,
+or in some cases launched in a separate tab or window,
+launched via a link in a LON-CAPA page with standard inline
+menu.
+
+=item $brcrum
+
+breadcrumbs for unregistered urls
+(i.e., external resources in Supplemental Content).
+
+=item $absolute
+
+contains protocol (http or https) followed by
+the hostname, if menu items in the standard LON-CAPA
+interface created by the call to loncommon::start_page()
+within &wrapper() need to use absolute URLs rather than
+relative URLs.
+
+That will be the case where an external resource has been
+served from port 80, when the server customarily serves
+requests using Apache/SSL (i.e., port 443). mod_rewrite
+is used to switch requests for external resources and
+the syllabus: /public///syllabus
+(which might also point at an external resource)
+from https:// to http:// where the the URL of the remote site
+specified in the resource itself is http://.
+
+This is done to avoid default mixed content blocking
+in Firefox 23 and later, when serving from Apache/SSL.
+
+=item $is_ext
+true if URL is for an external resource. Default true value
+is 1 (display in iframe, unless $uselink is true).
+If external resource is to be displayed in a tab,
+value of $is_ext will be tab, if to be displayed in a pop-up window,
+value of $is_ext will be window.
+=item $is_pdf
+true if URL is for a PDF (based on file extension).
+=item $exttool
+If URL is for an External Tool, will contain the target type: iframe, window or tab.
+=item $linktext
+
+optional. If URL is for an External Tool, and target type is window or tab,
+then the link text may be an option set in the course for each tool instance,
+or may be a default defined in the domain for all instances of the tool.
+
+=item $explanation
+
+optional. If URL is for an External Tool, and target type is window or tab,
+then the explanation is an option set in the course for each tool instance,
+or may be a default defined in the domain for all instances of the tool.
+
+=item $title
+
+optional. If wrapped item is a PDF, and $clientmobile is true,
+a link to a PDF is shown. The "title" will be displayed
+above the link, but if not provided as an arg, $env{'form.title'}
+will be used, otherwise, the filename will be displayed (unless
+hidden URL set for the resource).
+
+=item $width
+
+optional. If URL is for an External Tool, and target type is window,
+then a default width may have been defined in the domain for all instances of
+the tool. If so, that width will be used for the window opened (via a link)
+to launch the external tool. If the URL is for an External Resource, and
+$is_ext is window, then a default width (px) may have been defined in the current
+course for all external resource instances.
+
+=item $height
+
+optional. If URL is for an External Tool, and target type is window,
+then a default height may have been defined in the domain for all instances of
+the tool. If so, that height will be used for the window opened (via a link)
+to launch the external tool. If the URL is for an External Resource, and
+$is_ext is window, then a default height (px) may have been defined in the current
+course for all external resource instances.
+
+=item $reuse
+
+optional. If the URL is for an External Resource, and $is_ext is tab or window,
+then $reuse will be true if the same tab or window is to be reused for display
+of all external resource instances in a a course.
+
+=back
+
+Returns markup for the entire page.
+
+=item handler()
+
+Content handler for requests for: /adm/wrapper/...
+used for content to be displayed in an iframe, or launched in a separate tab
+or window via a link. The target URL is extracted from the requested URL, by
+removing the /adm/wrapper prefix.
+
+The target URL will typically be a PDF served from the current server, an
+external resource URL served from a different server, or an external tool
+(from an LTI Provider) launched from LON-CAPA (as LTI Consumer) and launched
+via a link.
+
+If the request included forceedit in the query string, and the requester has
+rights to modify course content, then the editor will be displayed to allow
+changes to be made to the resource (e.g., change the URL of the external resource,
+or change the setting for the external tool instance).
+
+If not in edit mode, then the wrapper() subroutine will be called to generate the
+standard LON-CAPA inline menu, and then either a link to launch a separate tab or
+window, or an iframe to display the content inline.
+
+=back
+
+=cut