1: # The LearningOnline Network
2: #
3: # Read maps into a 'big hash'.
4: #
5: # $Id: lonmap.pm,v 1.1 2011/09/07 10:58:36 foxr Exp $
6: #
7: # Copyright Michigan State University Board of Trustees
8: #
9: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
10: #
11: # LON-CAPA is free software; you can redistribute it and/or modify
12: # it under the terms of the GNU General Public License as published by
13: # the Free Software Foundation; either version 2 of the License, or
14: # (at your option) any later version.
15: #
16: # LON-CAPA is distributed in the hope that it will be useful,
17: # but WITHOUT ANY WARRANTY; without even the implied warranty of
18: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19: # GNU General Public License for more details.
20: #
21: # You should have received a copy of the GNU General Public License
22: # along with LON-CAPA; if not, write to the Free Software
23: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24: #
25: # /home/httpd/html/adm/gpl.txt
26: #
27: # http://www.lon-capa.org/
28: #
29: ###
30:
31: package lonmap;
32: use strict;
33:
34: #------------- Required external modules.
35:
36: use Error qw(:try);
37:
38: use HTML::TokeParser;
39:
40:
41: use Apache::LONCAPA;
42: use Apache::lonnet;
43:
44: #------------- File scoped variables:
45:
46: my $map_number = 1; # keep track of maps within the course.
47: my $course_id; # Will be the id of the course being read in.
48:
49: #
50: # The variables below are auxiliary hashes. They will be tacked onto the
51: # big hash though currently not used by clients.. you never know about later.
52: #
53:
54: my %randompick;
55: my %randompickseed;
56: my %randomorder;
57: my %encurl;
58: my %hiddenurl;
59: my @cond; # Array of conditions.
60:
61: #
62: # Other stuff we make global (sigh) so that it does not need
63: # to be passed around all the time:
64: #
65:
66: my $username; # User for whom the map is being read.
67: my $userdomain; # Domain the user lives in.
68: my %mapalias_cache; # Keeps track of map aliases -> resources detects duplicates.
69:
70: #------------- Executable code:
71:
72:
73: #----------------------------------------------------------------
74: #
75: # General utilities:
76:
77:
78: #
79: # I _think_ this does common sub-expression simplification and
80: # optimization for condition strings...based on common pattern matching.
81: # Parameters:
82: # expression - the condition expression string.
83: # Returns:
84: # The optimized expression if an optimization could be found.
85: #
86: # NOTE:
87: # Added repetetive optimization..it's possible that an
88: # optimization results in an expression that can be recognized further in
89: # a subsequent optimization pass:
90: #
91:
92: sub simplify {
93: my $expression=shift;
94: my $prior = ''; # This is safe as a null expression is pretty optimal.
95:
96: while ($prior ne $expression) {
97: $prior = $expression; # Stop when the substitutions below do nothing.
98: # (0&1) = 1
99: $expression=~s/\(0\&([_\.\d]+)\)/$1/g;
100: # (8)=8
101: $expression=~s/\(([_\.\d]+)\)/$1/g;
102: # 8&8=8
103: $expression=~s/([^_\.\d])([_\.\d]+)\&\2([^_\.\d])/$1$2$3/g;
104: # 8|8=8
105: $expression=~s/([^_\.\d])([_\.\d]+)(?:\|\2)+([^_\.\d])/$1$2$3/g;
106: # (5&3)&4=5&3&4
107: $expression=~s/\(([_\.\d]+)((?:\&[_\.\d]+)+)\)\&([_\.\d]+[^_\.\d])/$1$2\&$3/g;
108: # (((5&3)|(4&6)))=((5&3)|(4&6))
109: $expression=~
110: s/\((\(\([_\.\d]+(?:\&[_\.\d]+)*\)(?:\|\([_\.\d]+(?:\&[_\.\d]+)*\))+\))\)/$1/g;
111: # ((5&3)|(4&6))|(1&2)=(5&3)|(4&6)|(1&2)
112: $expression=~
113: s/\((\([_\.\d]+(?:\&[_\.\d]+)*\))((?:\|\([_\.\d]+(?:\&[_\.\d]+)*\))+)\)\|(\([_\.\d]+(?:\&[_\.\d]+)*\))/\($1$2\|$3\)/g;
114: }
115: return $expression;
116: }
117:
118:
119: #
120: # Merge the conditions into the big hash
121: # these will result in hash entries of the form:
122: # 'condition.n' where 'n' is the array index of the condition in the
123: # @cond array above.
124: #
125: # Parameters:
126: # $hash - big hashthat's being built up.
127: #
128: sub merge_conditions {
129: my $hash = shift;
130:
131: for (my $i = 0; i < scalar(@cond); i++) {
132: $hash->{'condition' . '.' . $i} = $cond[$i];
133: }
134: }
135:
136: # Merge the contents of a 'child hash' into a parent hash hanging it off another key.
137: # This is _not_ done by hanging a reference to the child hash as the parent may be
138: # bound to a GDBM file e.g. and shared by more than one process ..and references are
139: # pretty clearly not going to work across process boundaries.
140: #
141: # Parameters:
142: # $parent - The hash to which the child will be merged (reference)
143: # $key - The key in the parent hash on which the child elements will be hung.
144: # given a key named $childkey the final parent hash entry will be
145: # $parent . '.' $childkey
146: # $child - The hash whose contents we merge into the parent (reference)
147: #
148: sub merge_hash {
149: my ($parent, $key, $child) = @_;
150:
151: foreach my $childkey (keys (%$child)) {
152: $parent->{$key . '.' . $childkey} = $child->{$childkey};
153: }
154: }
155:
156: #----------------------------------------------------------------------------------
157: #
158: # Code to keep track of map aliases and to determine if there are doubly
159: # defined aliases.
160: #
161:
162: #
163: # Maintains the mapalias hash. This is a hash of arrays. Each array
164: # is indexed by the alias and contains the set of resource ids pointed to by that
165: # alias. In an ideal world, there will only be one element in each array.
166: # The point of this, however is to determine which aliases might be doubley defined
167: # due to map nesting e.g.
168: #
169: # Parameters:
170: # $value - Alias name.
171: # $resid - Resource id pointed to by the alias.
172: #
173: #
174: sub count_mapalias {
175: my ($value,$resid) = @_;
176: push(@{ $mapalias_cache{$value} }, $resid);
177: }
178: #
179: # Looks at each key in the mapalias hash and, for each case where an
180: # alias points to more than one value adds an error text to the
181: # result string.'
182: #
183: # Parameters:
184: # none
185: # Implicit inputs
186: # %mapalias - a hash that is indexed by map aliases and contains for each key
187: # an array of the resource id's the alias 'points to'.
188: # Returns:
189: # A hopefully empty string of messages that descsribe the aliases that have more
190: # than one value. This string is formatted like an html list.
191: #
192: #
193: sub get_mapalias_errors {
194: my $error_text;
195: foreach my $mapalias (sort(keys(%mapalias_cache))) {
196: next if (scalar(@{ $mapalias_cache{$mapalias} } ) == 1);
197: my $count;
198: my $which =
199: join('</li><li>',
200: map {
201: my $id = $_;
202: if (exists($hash{'src_'.$id})) {
203: $count++;
204: }
205: my ($mapid) = split(/\./,$id);
206: &mt('Resource "[_1]" <br /> in Map "[_2]"',
207: $hash{'title_'.$id},
208: $hash{'title_'.$hash{'ids_'.$hash{'map_id_'.$mapid}}});
209: } (@{ $mapalias_cache{$mapalias} }));
210: next if ($count < 2);
211: $error_text .= '<div class="LC_error">'.
212: &mt('Error: Found the mapalias "[_1]" defined multiple times.',
213: $mapalias).
214: '</div><ul><li>'.$which.'</li></ul>';
215: }
216: &clear_mapalias_count();
217: return $error_text;
218: }
219: #
220: # Clears the map aliase hash.
221: #
222: sub clear_mapalias_count {
223: undef(%mapalias_cache);
224: }
225:
226: #----------------------------------------------------------------
227: #
228: # Code dealing with resource versions.
229: #
230:
231: #
232: # Create hash entries for each version of the course.
233: # Parameters:
234: # $cenv - Reference to a course environment from lonnet::coursedescription.
235: # $hash - Reference to a hash that will be populated.
236:
237: #
238: sub process_versions {
239: my ($cenv, $hash) = @_;
240:
241:
242: my %versions = &Apache::lonnet::dump('resourceversions',
243: $cenv->{'domain'},
244: $cenv->{'num'});
245:
246: foreach my $ver (keys (%versions)) {
247: if ($ver =~/^error\:/) { # lonc/lond transaction failed.
248: throw Error::Simple('lonc/lond returned error: ' . $ver);
249: }
250: $hash->{'version_'.$ver} = $versions{$ver};
251: }
252: }
253:
254: #
255: # Generate text for a version discrepancy error:
256: # Parameters:
257: # $uri - URI of the resource.
258: # $used - Version used.
259: # $unused - Veresion of duplicate.
260: #
261: sub versionerror {
262: my ($uri, $used, $unused) = @_;
263: my ($uri,$usedversion,$unusedversion)=@_;
264: return '<br />'.
265: &mt('Version discrepancy: resource [_1] included in both version [_2] and version [_3]. Using version [_2].',
266: $uri,$used,$unused).'<br />';
267:
268: }
269:
270: # Removes the version number from a URI and returns the resulting
271: # URI (e.g. mumbly.version.stuff => mumbly.stuff).
272: #
273: # If the URI has not been seen with a version before the
274: # hash{'version_'.resultingURI} is set to the version number.
275: # If the hash has already been seen, but differs then
276: # an error is raised.
277: #
278: # Parameters:
279: # $uri - potentially with a version.
280: # $hash - reference to a hash to fill in.
281: # Returns:
282: # URI with the version cut out.
283: #
284: sub vesiontrack {
285: my ($uri, $hash) = @_;
286:
287:
288: if ($uri=~/\.(\d+)\.\w+$/) { # URI like *.n.text it's version 'n'
289: my $version=$1;
290: $uri=~s/\.\d+\.(\w+)$/\.$1/; # elide the version.
291: unless ($hash->{'version_'.$uri}) {
292: $hash->{'version_'.$uri}=$version;
293: } elsif ($version!=$hash->{'version_'.$uri}) {
294: throw Error::Simple(&versionerror($uri,$hash{'version_'.$uri},$version));
295: }
296: }
297: return $uri;
298: }
299: #
300: # Appends the version of a resource to its uri and also caches the
301: # URI (contents?) on the local server
302: #
303: # Parameters:
304: # $uri - URI of the course (without version informatino.
305: # $hash - What we have of the big hash.
306: #
307: # Side-Effects:
308: # The URI is cached by memcached.
309: #
310: # Returns:
311: # The version appended URI.
312: #
313: sub append_version {
314: my ($uri, $hash) = @_;
315:
316: # Create the key for the cache entry.
317:
318: my $key = $course_id . '_' . &Apache::lonnet::clutter($uri);
319:
320: # If there is a version it will already be in the hash:
321:
322: if ($hash->{'version_' . $uri}) {
323: my $version = $hash->{'version_' . $uri};
324: if ($version eq 'mostrecent') {
325: return $uri; # Most recent version does not require decoration (or caching?).
326: }
327: if ($version eq
328: &Apache::lonnet::getversion(&Apache::lonnet::filelocation('', $uri))) {
329: return $uri; # version matches the most recent file version?
330: }
331: $uri =~ s/\.(\w+)$/\.$version\.$1/; # insert the versino prior to the last .word.
332: }
333:
334: # cache the version:
335:
336: &Apache::lonnet::do_cache_new('courseresversion', $key,
337: &Apache::lonnet::declutter($uri), 600);
338:
339: return $uri;
340:
341: }
342: #--------------------------------------------------------------------------------
343: # Post processing subs:
344: sub hiddenurls {
345: my $hash = shift;
346:
347: my $randomoutentry='';
348: foreach my $rid (keys %randompick) {
349: my $rndpick=$randompick{$rid};
350: my $mpc=$hash->{'map_pc_'.$hash->{'src_'.$rid}};
351: # ------------------------------------------- put existing resources into array
352: my @currentrids=();
353: foreach my $key (sort(keys(%$hash))) {
354: if ($key=~/^src_($mpc\.\d+)/) {
355: if ($hash->{'src_'.$1}) { push @currentrids, $1; }
356: }
357: }
358: # rids are number.number and we want to numercially sort on
359: # the second number
360: @currentrids=sort {
361: my (undef,$aid)=split(/\./,$a);
362: my (undef,$bid)=split(/\./,$b);
363: $aid <=> $bid;
364: } @currentrids;
365: next if ($#currentrids<$rndpick);
366: # -------------------------------- randomly eliminate the ones that should stay
367: my (undef,$id)=split(/\./,$rid);
368: if ($randompickseed{$rid}) { $id=$randompickseed{$rid}; }
369: my $rndseed=&Apache::lonnet::rndseed($id); # use id instead of symb
370: &Apache::lonnet::setup_random_from_rndseed($rndseed);
371: my @whichids=&Math::Random::random_permuted_index($#currentrids+1);
372: for (my $i=1;$i<=$rndpick;$i++) { $currentrids[$whichids[$i]]=''; }
373: #&Apache::lonnet::logthis("$id,$rndseed,".join(':',@whichids));
374: # -------------------------------------------------------- delete the leftovers
375: for (my $k=0; $k<=$#currentrids; $k++) {
376: if ($currentrids[$k]) {
377: $hash->{'randomout_'.$currentrids[$k]}=1;
378: my ($mapid,$resid)=split(/\./,$currentrids[$k]);
379: $randomoutentry.='&'.
380: &Apache::lonnet::encode_symb($hash->{'map_id_'.$mapid},
381: $resid,
382: $hash->{'src_'.$currentrids[$k]}
383: ).'&';
384: }
385: }
386: }
387: # ------------------------------ take care of explicitly hidden urls or folders
388: foreach my $rid (keys %hiddenurl) {
389: $hash->{'randomout_'.$rid}=1;
390: my ($mapid,$resid)=split(/\./,$rid);
391: $randomoutentry.='&'.
392: &Apache::lonnet::encode_symb($hash->{'map_id_'.$mapid},$resid,
393: $hash->{'src_'.$rid}).'&';
394: }
395: # --------------------------------------- add randomout to the hash.
396: if ($randomoutentry) {
397: $hash->{'acc.randomout'} = $randomoutentry;
398:
399: }
400: }
401:
402: #
403: # It's not so clear to me what this sub does.
404: #
405: # Parameters
406: # uri - URI from the course description hash.
407: # short - Course short name.
408: # fn - Course filename.
409: # hash - Reference to the big hash as filled in so far
410: #
411:
412: sub accinit {
413: my ($uri,$short,$fn)=@_;
414: my %acchash=();
415: my %captured=();
416: my $condcounter=0;
417: $acchash{'acc.cond.'.$short.'.0'}=0;
418:
419: # This loop is only interested in conditions and
420: # parameters in the big hash:
421:
422: foreach my $key (keys(%$hash)) {
423:
424: # conditions:
425:
426: if ($key=~/^conditions/) {
427: my $expr=$hash->{$key};
428:
429: # try to find and factor out common sub-expressions
430: # Any subexpression that is found is simplified, removed from
431: # the original condition expression and the simplified sub-expression
432: # substituted back in to the epxression..I'm not actually convinced this
433: # factors anything out...but instead maybe simplifies common factors(?)
434:
435: foreach my $sub ($expr=~m/(\(\([_\.\d]+(?:\&[_\.\d]+)+\)(?:\|\([_\.\d]+(?:\&[_\.\d]+)+\))+\))/g) {
436: my $orig=$sub;
437:
438: my ($factor) = ($sub=~/\(\(([_\.\d]+\&(:?[_\.\d]+\&)*)(?:[_\.\d]+\&*)+\)(?:\|\(\1(?:[_\.\d]+\&*)+\))+\)/);
439: next if (!defined($factor));
440:
441: $sub=~s/\Q$factor\E//g;
442: $sub=~s/^\(/\($factor\(/;
443: $sub.=')';
444: $sub=simplify($sub);
445: $expr=~s/\Q$orig\E/$sub/;
446: }
447: $hash->{$key}=$expr;
448:
449: # If not yet seen, record in acchash and that we've seen it.
450:
451: unless (defined($captured{$expr})) {
452: $condcounter++;
453: $captured{$expr}=$condcounter;
454: $acchash{'acc.cond.'.$short.'.'.$condcounter}=$expr;
455: }
456: # Parameters:
457:
458: } elsif ($key=~/^param_(\d+)\.(\d+)/) {
459: my $prefix=&Apache::lonnet::encode_symb($hash->{'map_id_'.$1},$2,
460: $hash->{'src_'.$1.'.'.$2});
461: foreach my $param (split(/\&/,$hash->{$key})) {
462: my ($typename,$value)=split(/\=/,$param);
463: my ($type,$name)=split(/\:/,$typename);
464: $parmhash{$prefix.'.'.&unescape($name)}=
465: &unescape($value);
466: $parmhash{$prefix.'.'.&unescape($name).'.type'}=
467: &unescape($type);
468: }
469: }
470: }
471: # This loop only processes id entries in the big hash.
472:
473: foreach my $key (keys(%$hash)) {
474: if ($key=~/^ids/) {
475: foreach my $resid (split(/\,/,$hash->{$key})) {
476: my $uri=$hash->{'src_'.$resid};
477: my ($uripath,$urifile) =
478: &Apache::lonnet::split_uri_for_cond($uri);
479: if ($uripath) {
480: my $uricond='0';
481: if (defined($hash->{'conditions_'.$resid})) {
482: $uricond=$captured{$hash->{'conditions_'.$resid}};
483: }
484: if (defined($acchash{'acc.res.'.$short.'.'.$uripath})) {
485: if ($acchash{'acc.res.'.$short.'.'.$uripath}=~
486: /(\&\Q$urifile\E\:[^\&]*)/) {
487: my $replace=$1;
488: my $regexp=$replace;
489: #$regexp=~s/\|/\\\|/g;
490: $acchash{'acc.res.'.$short.'.'.$uripath} =~
491: s/\Q$regexp\E/$replace\|$uricond/;
492: } else {
493: $acchash{'acc.res.'.$short.'.'.$uripath}.=
494: $urifile.':'.$uricond.'&';
495: }
496: } else {
497: $acchash{'acc.res.'.$short.'.'.$uripath}=
498: '&'.$urifile.':'.$uricond.'&';
499: }
500: }
501: }
502: }
503: }
504: $acchash{'acc.res.'.$short.'.'}='&:0&';
505: my $courseuri=$uri;
506: $courseuri=~s/^\/res\///;
507: my $regexp = 1;
508:
509: &merge_hash($hash, '', \%acchash); # there's already an acc prefix in the hash keys.
510:
511:
512: }
513:
514:
515: #
516: # Traces a route recursively through the map after it has been loaded
517: # (I believe this really visits each resource that is reachable fromt he
518: # start top node.
519: #
520: # - Marks hidden resources as hidden.
521: # - Marks which resource URL's must be encrypted.
522: # - Figures out (if necessary) the first resource in the map.
523: # - Further builds the chunks of the big hash that define how
524: # conditions work
525: #
526: # Note that the tracing strategy won't visit resources that are not linked to
527: # anything or islands in the map (groups of resources that form a path but are not
528: # linked in to the path that can be traced from the start resource...but that's ok
529: # because by definition, those resources are not reachable by users of the course.
530: #
531: # Parameters:
532: # sofar - _URI of the prior entry or 0 if this is the top.
533: # rid - URI of the resource to visit.
534: # beenhere - list of resources (each resource enclosed by &'s) that have
535: # already been visited.
536: # encflag - If true the resource that resulted in a recursive call to us
537: # has an encoded URL (which means contained resources should too).
538: # hdnflag - If true,the resource that resulted in a recursive call to us
539: # was hidden (which means contained resources should be hidden too).
540: # hash - Reference to the hash we are traversing.
541: # Returns
542: # new value indicating how far the map has been traversed (the sofar).
543: #
544: sub traceroute {
545: my ($sofar,$rid,$beenhere,$encflag,$hdnflag)=@_;
546: my $newsofar=$sofar=simplify($sofar);
547:
548: unless ($beenhere=~/\&\Q$rid\E\&/) {
549: $beenhere.=$rid.'&';
550: my ($mapid,$resid)=split(/\./,$rid);
551: my $symb=&Apache::lonnet::encode_symb($hash->{'map_id_'.$mapid},$resid,
552: $hash->{'src_'.$rid});
553: my $hidden=&Apache::lonnet::EXT('resource.0.hiddenresource',$symb);
554:
555: if ($hdnflag || lc($hidden) eq 'yes') {
556: $hiddenurl{$rid}=1;
557: }
558: if (!$hdnflag && lc($hidden) eq 'no') {
559: delete($hiddenurl{$rid});
560: }
561:
562: my $encrypt=&Apache::lonnet::EXT('resource.0.encrypturl',$symb);
563: if ($encflag || lc($encrypt) eq 'yes') { $encurl{$rid}=1; }
564:
565: if (($retfrid eq '') && ($hash->{'src_'.$rid})
566: && ($hash->{'src_'.$rid}!~/\.sequence$/)) {
567: $retfrid=$rid;
568: }
569:
570: if (defined($hash->{'conditions_'.$rid})) {
571: $hash->{'conditions_'.$rid}=simplify(
572: '('.$hash->{'conditions_'.$rid}.')|('.$sofar.')');
573: } else {
574: $hash->{'conditions_'.$rid}=$sofar;
575: }
576:
577: # if the expression is just the 0th condition keep it
578: # otherwise leave a pointer to this condition expression
579:
580: $newsofar = ($sofar eq '0') ? $sofar : '_'.$rid;
581:
582: # Recurse if the resource is a map:
583:
584: if (defined($hash->{'is_map_'.$rid})) {
585: if (defined($hash->{'map_start_'.$hash->{'src_'.$rid}})) {
586: $sofar=$newsofar=
587: &traceroute($sofar,
588: $hash->{'map_start_'.$hash->{'src_'.$rid}},
589: $beenhere,
590: $encflag || $encurl{$rid},
591: $hdnflag || $hiddenurl{$rid});
592: }
593: }
594:
595: # Processes links to this resource:
596: # - verify the existence of any conditionals on the link to here.
597: # - Recurse to any resources linked to us.
598: #
599: if (defined($hash->{'to_'.$rid})) {
600: foreach my $id (split(/\,/,$hash->{'to_'.$rid})) {
601: my $further=$sofar;
602: #
603: # If there's a condition associated with this link be sure
604: # it's been defined else that's an error:
605: #
606: if ($hash->{'undercond_'.$id}) {
607: if (defined($hash->{'condid_'.$hash->{'undercond_'.$id}})) {
608: $further=simplify('('.'_'.$rid.')&('.
609: $hash->{'condid_'.$hash->{'undercond_'.$id}}.')');
610: } else {
611: $errtext.=&mt('<br />Undefined condition ID: [_1]',$hash->{'undercond_'.$id});
612: throw Error::Simple($errtext);
613: }
614: }
615: # Recurse to resoruces that have to's to us.
616: $newsofar=&traceroute($further,$hash->{'goesto_'.$id},$beenhere,
617: $encflag,$hdnflag);
618: }
619: }
620: }
621: return $newsofar;
622: }
623:
624:
625: #---------------------------------------------------------------------------------
626: #
627: # Map parsing code:
628: #
629:
630: #
631: # Parse the <param> tag. for most parameters, the only action is to define/extend
632: # a has entry for {'param_{refid}'} where refid is the resource the parameter is
633: # attached to and the value built up is an & separated list of parameters of the form:
634: # type:part.name=value
635: #
636: # In addition there is special case code for:
637: # - randompick
638: # - randompickseed
639: # - randomorder
640: #
641: # - encrypturl
642: # - hiddenresource
643: #
644: # Parameters:
645: # token - The token array from HTML::TokeParse we mostly care about element [2]
646: # which is a hash of attribute => values supplied in the tag
647: # (remember this sub is only processing start tag tokens).
648: # mno - Map number. This is used to qualify resource ids within a map
649: # to make them unique course wide (a process known as uniquifaction).
650: # hash - Reference to the hash we are building.
651: #
652: sub parse_param {
653: my ($token, $mno, $hash) = @_;
654:
655: # Qualify the reference and name by the map number and part number.
656: # if no explicit part number is supplied, 0 is the implicit part num.
657:
658: my $referid=$mno.'.'.$token->[2]->{'to'}; # Resource param applies to.
659: my $name=$token->[2]->{'name'}; # Name of parameter
660: my $part;
661:
662:
663: if ($name=~/^parameter_(.*)_/) {
664: $part=$1;
665: } else {
666: $part=0;
667: }
668:
669: # Peel the parameter_ off the parameter name.
670:
671: $name=~s/^.*_([^_]*)$/$1/;
672:
673: # The value is:
674: # type.part.name.value
675:
676: my $newparam=
677: &escape($token->[2]->{'type'}).':'.
678: &escape($part.'.'.$name).'='.
679: &escape($token->[2]->{'value'});
680:
681: # The hash key is param_resourceid.
682: # Multiple parameters for a single resource are & separated in the hash.
683:
684:
685: if (defined($hash->{'param_'.$referid})) {
686: $hash->{'param_'.$referid}.='&'.$newparam;
687: } else {
688: $hash->{'param_'.$referid}=''.$newparam;
689: }
690: #
691: # These parameters have to do with randomly selecting
692: # resources, therefore a separate hash is also created to
693: # make it easy to locate them when actually computing the resource set later on
694: # See the code conditionalized by ($randomize) in read_map().
695:
696: if ($token->[2]->{'name'}=~/^parameter_(0_)*randompick$/) { # Random selection turned on
697: $randompick{$referid}=$token->[2]->{'value'};
698: }
699: if ($token->[2]->{'name'}=~/^parameter_(0_)*randompickseed$/) { # Randomseed provided.
700: $randompickseed{$referid}=$token->[2]->{'value'};
701: }
702: if ($token->[2]->{'name'}=~/^parameter_(0_)*randomorder$/) { # Random order turned on.
703: $randomorder{$referid}=$token->[2]->{'value'};
704: }
705:
706: # These parameters have to do with how the URLs of resources are presented to
707: # course members(?). encrypturl presents encypted url's while
708: # hiddenresource hides the URL.
709: #
710:
711: if ($token->[2]->{'name'}=~/^parameter_(0_)*encrypturl$/) {
712: if ($token->[2]->{'value'}=~/^yes$/i) {
713: $encurl{$referid}=1;
714: }
715: }
716: if ($token->[2]->{'name'}=~/^parameter_(0_)*hiddenresource$/) {
717: if ($token->[2]->{'value'}=~/^yes$/i) {
718: $hiddenurl{$referid}=1;
719: }
720: }
721:
722: }
723:
724:
725: #
726: # Parses a resource tag to produce the value to push into the
727: # map_ids array.
728: #
729: #
730: # Information about the actual type of resource is provided by the file extension
731: # of the uri (e.g. .problem, .sequence etc. etc.).
732: #
733: # Parameters:
734: # $token - A token from HTML::TokeParser
735: # This is an array that describes the most recently parsed HTML item.
736: # $lpc - Map nesting level (?)
737: # $ispage - True if this resource is encapsulated in a .page (assembled resourcde).
738: # $uri - URI of the enclosing resource.
739: # $hash - Reference to the hash we are building.
740: #
741: # Returns:
742: # Value of the id attribute of the tag.
743: #
744: # Note:
745: # The token is an array that contains the following elements:
746: # [0] => 'S' indicating this is a start token
747: # [1] => 'resource' indicating this tag is a <resource> tag.
748: # [2] => Hash of attribute =>value pairs.
749: # [3] => @(keys [2]).
750: # [4] => unused.
751: #
752: # The attributes of the resourcde tag include:
753: #
754: # id - The resource id.
755: # src - The URI of the resource.
756: # type - The resource type (e.g. start and finish).
757: # title - The resource title.
758: #
759:
760: sub parse_resource {
761: my ($token,$lpc,$ispage,$uri, $hash) = @_;
762:
763: # I refuse to countenance code like this that has
764: # such a dirty side effect (and forcing this sub to be called within a loop).
765: #
766: # if ($token->[2]->{'type'} eq 'zombie') { next; }
767: #
768: # The original code both returns _and_ skips to the next pass of the >caller's<
769: # loop, that's just dirty.
770: #
771:
772: # Zombie resources don't produce anything useful.
773:
774: if ($token->[2]->{'type'} eq 'zombie') {
775: return undef;
776: }
777:
778: my $rid=$lpc.'.'.$token->[2]->{'id'}; # Resource id in hash is levelcounter.id-in-xml.
779:
780: # Save the hash element type and title:
781:
782: $hash->{'kind_'.$rid}='res';
783: $hash->{'title_'.$rid}=$token->[2]->{'title'};
784:
785: # Get the version free URI for the resource.
786: # If a 'version' attribute was supplied, and this resource's version
787: # information has not yet been stored, store it.
788: #
789:
790:
791: my $turi=&versiontrack($token->[2]->{'src'});
792: if ($token->[2]->{'version'}) {
793: unless ($hash->{'version_'.$turi}) {
794:
795: #Where does the value of $1 below come from?
796: #$1 for the regexps in versiontrack should have gone out of scope.
797: #
798: # I think this may be dead code since versiontrack ought to set
799: # this hash element(?).
800: #
801: $hash->{'version_'.$turi}=$1;
802: }
803: }
804: # Pull out the title and do entity substitution on &colon
805: # Q: Why no other entity substitutions?
806:
807: my $title=$token->[2]->{'title'};
808: $title=~s/\&colon\;/\:/gs;
809:
810:
811:
812: # I think the point of all this code is to construct a final
813: # URI that apache and its rewrite rules can use to
814: # fetch the resource. Thi s sonly necessary if the resource
815: # is not a page. If the resource is a page then it must be
816: # assembled (at fetch time?).
817:
818: unless ($ispage) {
819: $turi=~/\.(\w+)$/;
820: my $embstyle=&Apache::loncommon::fileembstyle($1);
821: if ($token->[2]->{'external'} eq 'true') { # external
822: $turi=~s/^https?\:\/\//\/adm\/wrapper\/ext\//;
823: } elsif ($turi=~/^\/*uploaded\//) { # uploaded
824: if (($embstyle eq 'img')
825: || ($embstyle eq 'emb')
826: || ($embstyle eq 'wrp')) {
827: $turi='/adm/wrapper'.$turi;
828: } elsif ($embstyle eq 'ssi') {
829: #do nothing with these
830: } elsif ($turi!~/\.(sequence|page)$/) {
831: $turi='/adm/coursedocs/showdoc'.$turi;
832: }
833: } elsif ($turi=~/\S/) { # normal non-empty internal resource
834: my $mapdir=$uri;
835: $mapdir=~s/[^\/]+$//;
836: $turi=&Apache::lonnet::hreflocation($mapdir,$turi);
837: if (($embstyle eq 'img')
838: || ($embstyle eq 'emb')
839: || ($embstyle eq 'wrp')) {
840: $turi='/adm/wrapper'.$turi;
841: }
842: }
843: }
844: # Store reverse lookup, remove query string resource 'ids'_uri => resource id.
845: # If the URI appears more than one time in the sequence, it's resourcde
846: # id's are constructed as a comma spearated list.
847:
848: my $idsuri=$turi;
849: $idsuri=~s/\?.+$//;
850: if (defined($hash->{'ids_'.$idsuri})) {
851: $hash->{'ids_'.$idsuri}.=','.$rid;
852: } else {
853: $hash->{'ids_'.$idsuri}=''.$rid;
854: }
855:
856:
857:
858: if ($turi=~/\/(syllabus|aboutme|navmaps|smppg|bulletinboard|viewclasslist)$/) {
859: $turi.='?register=1';
860: }
861:
862:
863: # resource id lookup: 'src'_resourc-di => URI decorated with a query
864: # parameter as above if necessary due to the resource type.
865:
866: $hash->{'src_'.$rid}=$turi;
867:
868: # Mark the external-ness of the resource:
869:
870: if ($token->[2]->{'external'} eq 'true') {
871: $hash->{'ext_'.$rid}='true:';
872: } else {
873: $hash->{'ext_'.$rid}='false:';
874: }
875:
876: # If the resource is a start/finish resource set those
877: # entries in the has so that navigation knows where everything starts.
878: # If there is a malformed sequence that has no start or no finish
879: # resource, should this be detected and errors thrown? How would such a
880: # resource come into being other than being manually constructed by a person
881: # and then uploaded? Could that happen if an author decided a sequence was almost
882: # right edited it by hand and then reuploaded it to 'fix it' but accidently cut the
883: # start or finish resources?
884: #
885: # All resourcess also get a type_id => (start | finish | normal) hash entr.
886: #
887: if ($token->[2]->{'type'}) {
888: $hash->{'type_'.$rid}=$token->[2]->{'type'};
889: if ($token->[2]->{'type'} eq 'start') {
890: $hash->{'map_start_'.$uri}="$rid";
891: }
892: if ($token->[2]->{'type'} eq 'finish') {
893: $hash->{'map_finish_'.$uri}="$rid";
894: }
895: } else {
896: $hash->{'type_'.$rid}='normal';
897: }
898:
899: # Sequences end pages are constructed entities. They require that the
900: # map that defines _them_ be loaded as well into the hash...with this resourcde
901: # as the base of the nesting.
902: # Resources like that are also marked with is_map_id => 1 entries.
903: #
904:
905: if (($turi=~/\.sequence$/) ||
906: ($turi=~/\.page$/)) {
907: $hash->{'is_map_'.$rid}=1;
908: &read_map($turi,$rid, $hash);
909: }
910: return $token->[2]->{'id'};
911: }
912:
913: # Links define how you are allowed to move from one resource to another.
914: # They are the transition edges in the directed graph that a map is.
915: # This sub takes informatino from a <link> tag and constructs the
916: # navigation bits and pieces of a map. There is no requirement that the
917: # resources that are linke are already defined, however clearly the map is
918: # badly broken if they are not _eventually_ defined.
919: #
920: # Note that links can be unconditional or conditional.
921: #
922: # Parameters:
923: # linkpc - The link counter for this level of map nesting (this is
924: # reset to zero by read_map prior to starting to process
925: # links for map).
926: # lpc - The map level ocounter (how deeply nested this map is in
927: # the hierarchy of maps that are recursively read in.
928: # to - resource id (within the XML) of the target of the edge.
929: # from - resource id (within the XML) of the source of the edge.
930: # condition- id of condition associated with the edge (also within the XML).
931: # hash - reference to the hash we are building.
932:
933: #
934:
935: sub make_link {
936: my ($linkpc,$lpc,$to,$from,$condition, $hash) = @_;
937:
938: # Compute fully qualified ids for the link, the
939: # and from/to by prepending lpc.
940: #
941:
942: my $linkid=$lpc.'.'.$linkpc;
943: my $goesto=$lpc.'.'.$to;
944: my $comesfrom=$lpc.'.'.$from;
945: my $undercond=0;
946:
947:
948: # If there is a condition, qualify it with the level counter.
949:
950: if ($condition) {
951: $undercond=$lpc.'.'.$condition;
952: }
953:
954: # Links are represnted by:
955: # goesto_.fuullyqualifedlinkid => fully qualified to
956: # comesfrom.fullyqualifiedlinkid => fully qualified from
957: # undercond_.fullyqualifiedlinkid => fully qualified condition id.
958:
959: $hash->{'goesto_'.$linkid}=$goesto;
960: $hash->{'comesfrom_'.$linkid}=$comesfrom;
961: $hash->{'undercond_'.$linkid}=$undercond;
962:
963: # In addition:
964: # to_.fully qualified from => comma separated list of
965: # link ids with that from.
966: # Similarly:
967: # from_.fully qualified to => comma separated list of link ids`
968: # with that to.
969: # That allows us given a resource id to know all edges that go to it
970: # and leave from it.
971: #
972:
973: if (defined($hash->{'to_'.$comesfrom})) {
974: $hash->{'to_'.$comesfrom}.=','.$linkid;
975: } else {
976: $hash->{'to_'.$comesfrom}=''.$linkid;
977: }
978: if (defined($hash->{'from_'.$goesto})) {
979: $hash->{'from_'.$goesto}.=','.$linkid;
980: } else {
981: $hash->{'from_'.$goesto}=''.$linkid;
982: }
983: }
984:
985: # ------------------------------------------------------------------- Condition
986: #
987: # Processes <condition> tags, storing sufficient information about them
988: # in the hash so that they can be evaluated and used to conditionalize
989: # what is presented to the student.
990: #
991: # these can have the following attributes
992: #
993: # id = A unique identifier of the condition within the map.
994: #
995: # value = Is a perl script-let that, when evaluated in safe space
996: # determines whether or not the condition is true.
997: # Normally this takes the form of a test on an Apache::lonnet::EXT call
998: # to find the value of variable associated with a resource in the
999: # map identified by a mapalias.
1000: # Here's a fragment of XML code that illustrates this:
1001: #
1002: # <param to="5" value="mainproblem" name="parameter_0_mapalias" type="string" />
1003: # <resource src="" id="1" type="start" title="Start" />
1004: # <resource src="/res/msu/albertel/b_and_c/p1.problem" id="5" title="p1.problem" />
1005: # <condition value="&EXT('user.resource.resource.0.tries','mainproblem')
1006: # <2 " id="61" type="stop" />
1007: # <link to="5" index="1" from="1" condition="61" />
1008: #
1009: # In this fragment:
1010: # - The param tag establishes an alias to resource id 5 of 'mainproblem'.
1011: # - The resource that is the start of the map is identified.
1012: # - The resource tag identifies the resource associated with this tag
1013: # and gives it the id 5.
1014: # - The condition is true if the tries variable associated with mainproblem
1015: # is less than 2 (that is the user has had more than 2 tries).
1016: # The condition type is a stop condition which inhibits(?) the associated
1017: # link if the condition is false.
1018: # - The link to resource 5 from resource 1 is affected by this condition.
1019: #
1020: # type = Type of the condition. The type determines how the condition affects the
1021: # link associated with it and is one of
1022: # - 'force'
1023: # - 'stop'
1024: # anything else including not supplied..which treated as:
1025: # - 'normal'.
1026: # Presumably maps get created by the resource assembly tool and therefore
1027: # illegal type values won't squirm their way into the XML.
1028: # hash - Reference to the hash we are trying to build up.
1029: #
1030: # Side effects:
1031: # - The kind_level-qualified-condition-id hash element is set to 'cond'.
1032: # - The condition text is pushed into the cond array and its element number is
1033: # set in the condid_level-qualified-condition-id element of the hash.
1034: # - The condition type is colon appneded to the cond array element for this condition.
1035: sub parse_condition {
1036: my ($token, $lpc, $hash) = @_;
1037: my $rid=$lpc.'.'.$token->[2]->{'id'};
1038:
1039: $hash->{'kind_'.$rid}='cond';
1040:
1041: my $condition = $token->[2]->{'value'};
1042: $condition =~ s/[\n\r]+/ /gs;
1043: push(@cond, $condition);
1044: $hash->{'condid_'.$rid}=$#cond;
1045: if ($token->[2]->{'type'}) {
1046: $cond[$#cond].=':'.$token->[2]->{'type'};
1047: } else {
1048: $cond[$#cond].=':normal';
1049: }
1050: }
1051:
1052: #
1053: # Parse mapalias parameters.
1054: # these are tags of the form:
1055: # <param to="nn"
1056: # value="some-alias-for-resourceid-nn"
1057: # name="parameter_0_mapalias"
1058: # type="string" />
1059: # A map alias is a textual name for a resource:
1060: # - The to attribute identifies the resource (this gets level qualified below)
1061: # - The value attributes provides the alias string.
1062: # - name must be of the regexp form: /^parameter_(0_)*mapalias$/
1063: # - e.g. the string 'parameter_' followed by 0 or more "0_" strings
1064: # terminating with the string 'mapalias'.
1065: # Examples:
1066: # 'parameter_mapalias', 'parameter_0_mapalias', parameter_0_0_mapalias'
1067: # Invalid to ids are silently ignored.
1068: #
1069: # Parameters:
1070: # token - The token array fromthe HMTML::TokeParser
1071: # lpc - The current map level counter.
1072: # hash - Reference to the hash that we are building.
1073: #
1074: sub parse_mapalias_param {
1075: my ($token, $lpc, $hash) = @_;
1076:
1077: # Fully qualify the to value and ignore the alias if there is no
1078: # corresponding resource.
1079:
1080: my $referid=$lpc.'.'.$token->[2]->{'to'};
1081: return if (!exists($hash->{'src_'.$referid}));
1082:
1083: # If this is a valid mapalias parameter,
1084: # Append the target id to the count_mapalias element for that
1085: # alias so that we can detect doubly defined aliases
1086: # e.g.:
1087: # <param to="1" value="george" name="parameter_0_mapalias" type="string" />
1088: # <param to="2" value="george" name="parameter_0_mapalias" type="string" />
1089: #
1090: # The example above is trivial but the case that's important has to do with
1091: # constructing a map that includes a nested map where the nested map may have
1092: # aliases that conflict with aliases established in the enclosing map.
1093: #
1094: # ...and create/update the hash mapalias entry to actually store the alias.
1095: #
1096:
1097: if ($token->[2]->{'name'}=~/^parameter_(0_)*mapalias$/) {
1098: &count_mapalias($token->[2]->{'value'},$referid);
1099: $hash->{'mapalias_'.$token->[2]->{'value'}}=$referid;
1100: }
1101: }
1102:
1103:
1104: #---------------------------------------------------------------------------------
1105: #
1106: # Code to process the map file.
1107:
1108: # read a map file and add it to the hash. Since a course map can contain resources
1109: # that are themselves maps, read_map might be recursively called.
1110: #
1111: # Parameters:
1112: # $uri - URI of the course itself (not the map file).
1113: # $parent_rid - map number qualified id of the parent of the map being read.
1114: # For the top level course map this is 0.0. For the first nested
1115: # map 1.n where n is the id of the resource within the
1116: # top level map and so on.
1117: # $hash - Reference to a hash that will become the big hash for the course
1118: # This hash is modified as per the map description.
1119: # Side-effects:
1120: # $map_number - Will be incremented. This keeps track of the number of the map
1121: # we are currently working on (see parent_rid above, the number to the
1122: # left of the . in $parent_rid is the map number).
1123: #
1124: #
1125: sub read_map {
1126: my ($uri, $parent_rid, $hash) = @_;
1127:
1128: # Check for duplication: A map may only be included once.
1129:
1130: if($hash->{'map_pc_' . $uri}) {
1131: throw Error::Simple('Duplicate map: ' $uri);
1132: }
1133: # count the map number and save it locally so that we don't lose it
1134: # when we recurse.
1135:
1136: $map_number++;
1137: my $lmap_no = $map_number;
1138:
1139: # save the map_pc and map_id elements of the hash for this map:
1140: # map_pc_uri is the map number of the map with that URI.
1141: # map_id_$lmap_no is the URI for this map level.
1142: #
1143: $hash->{'map_pc_' . $uri} = $lmap_no;
1144: $hash->{'map_id_' . $lmap_no} = $uri;
1145:
1146: # Create the path up to the top of the course.
1147: # this is in 'map_hierarchy_mapno' that's a comma separated path down to us
1148: # in the hierarchy:
1149:
1150: if ($parent_rid =~/^(\d+).\d+$/) {
1151: my $parent_no = $1; # Parent's map number.
1152: if (defined($hash->{'map_hierarchy_' . $parent_no})) {
1153: $hash->{'map_hierarchy_' . $lmap_no} =
1154: $hash->{'map_hierarchy_' . $parent_no} . ',' $parent_no;
1155: } else {
1156: # Only 1 level deep ..nothing to append to:
1157:
1158: $hash->{'map_hierarchy_' . $lmap_no} = $parent_no;
1159: }
1160: }
1161:
1162: # figure out the name of the map file we need to read.
1163: # ensure that it is a .page or a .sequence as those are the only
1164: # sorts of files that make sense for this sub
1165:
1166: my $filename = &Apache::lonnet::filelocation('', &append_version($uri, $hash));
1167: my $ispage = ($filename =~/\.page$/);
1168: unless ($ispage || ($filname =~ /\.sequence$/)) {
1169: throw Error::Simple(&mt("<br />Invalid map: <tt>[_1]</tt>", $filename));
1170: }
1171:
1172: $filename =~ /\.(\w+)$/;
1173:
1174: $hash->{'map_type_'.$lpc}=$1;
1175:
1176: # Repcopy the file and get its contents...report errors if we can't
1177:
1178: my $contents = &Apache::lonet::getfile($filename);
1179: if($contents eq -1) {
1180: throw Error::Simple(&mt('<br />Map not loaded: The file <tt>[_1]</tt> does not exist.',
1181: $filename));
1182: }
1183: # Now that we succesfully retrieved the file we can make our parsing passes over it:
1184: # parsing is done in passes:
1185: # 1. Parameters are parsed.
1186: # 2. Resource, links and conditions are parsed.
1187: #
1188: # post processing takes care of the case where the sequence is random ordered
1189: # or randomselected.
1190:
1191: # Parse the parameters, This pass only cares about start tags for <param>
1192: # tags.. this is because there is no body to a <param> tag.
1193: #
1194:
1195: my $parser = HTML::TokeParser->new($\contents);
1196: $parser->attr_encoded(1); # Don't interpret entities in attributes (leave &xyz; alone).
1197:
1198: while (my $token = $parser->get_token()) {
1199: if (($token->[0] eq 'S') && ($token->[1] eq 'param')) {
1200: &parse_param($token, $map_number, $hash);
1201: }
1202: }
1203:
1204: # ready for pass 2: Resource links and conditions.
1205: # Note that if the map is random-ordered link tags are computed by randomizing
1206: # resource order. Furthermore, since conditions are set on links rather than
1207: # resources, they are also not processed if random order is turned on.
1208: #
1209:
1210: $parser = HTML::TokeParser->new($\contents); # no way to reset the existing parser
1211: $parser->attr_encoded(1);
1212:
1213: my $linkpc=0;
1214: my $randomize = ($randomorder{$parent_rid} =~ /^yes$/i);
1215:
1216: my @map_ids;
1217: while (my $token = $parser->get_token) {
1218: next if ($token->[0] ne 'S');
1219:
1220: # Resource
1221:
1222: if ($token->[1] eq 'resource') {
1223: my $resource_id = &parse_resource($token,$lpc,$ispage,$uri, $hash);
1224: if (defined $resource_id) {
1225: push(@map_ids, $resource_id);
1226: }
1227:
1228: # Link
1229:
1230: } elsif ($token->[1] eq 'link' && !$randomize) {
1231: &make_link(++$linkpc,$lpc,$token->[2]->{'to'},
1232: $token->[2]->{'from'},
1233: $token->[2]->{'condition'}, $hash); # note ..condition may be undefined.
1234:
1235: # condition
1236:
1237: } elsif ($token->[1] eq 'condition' && !$randomize) {
1238: &parse_condition($token,$lpc, $hash);
1239: }
1240: }
1241:
1242: # This section handles random ordering by permuting the
1243: # IDs of the map according to the user's random seed.
1244: #
1245:
1246: if ($randomize) {
1247: if (!$env{'request.role.adv'}) {
1248: my $seed;
1249:
1250: # In the advanced role, the map's random seed
1251: # parameter is used as the basis for computing the
1252: # seed ... if it has been specified:
1253:
1254: if (defined($randompickseed{$parent_rid})) {
1255: $seed = $randompickseed{$parent_rid};
1256: } else {
1257:
1258: # Otherwise the parent's fully encoded symb is used.
1259:
1260: my ($mapid,$resid)=split(/\./,$parent_rid);
1261: my $symb=
1262: &Apache::lonnet::encode_symb($hash->{'map_id_'.$mapid},
1263: $resid,$hash->{'src_'.$parent_rid});
1264:
1265: $seed = $symb;
1266: }
1267:
1268:
1269: my $rndseed=&Apache::lonnet::rndseed($seed, $username, $userdomain);
1270: &Apache::lonnet::setup_random_from_rndseed($rndseed);
1271:
1272: # Take the set of map ids we have decoded and permute them to a
1273: # random order based on the seed set above. All of this is
1274: # processing the randomorder parameter if it is set, not
1275: # randompick.
1276:
1277: @map_ids=&math::Random::random_permutation(@map_ids);
1278: }
1279:
1280:
1281: my $from = shift(@map_ids);
1282: my $from_rid = $lpc.'.'.$from;
1283: $hash->{'map_start_'.$uri} = $from_rid;
1284: $hash->{'type_'.$from_rid}='start';
1285:
1286: # Create links to reflect the random re-ordering done above.
1287: # In the code to process the map XML, we did not process links or conditions
1288: # if randomorder was set. This means that for an instructor to choose
1289:
1290: while (my $to = shift(@map_ids)) {
1291: &make_link(++$linkpc,$lpc,$to,$from);
1292: my $to_rid = $lpc.'.'.$to;
1293: $hash->{'type_'.$to_rid}='normal';
1294: $from = $to;
1295: $from_rid = $to_rid;
1296: }
1297:
1298: $hash->{'map_finish_'.$uri}= $from_rid;
1299: $hash->{'type_'.$from_rid}='finish';
1300: }
1301:
1302: # The last parsing pass parses the <mapalias> tags that associate a name
1303: # with resource ids.
1304:
1305: $parser = HTML::TokeParser->new(\$contents);
1306: $parser->attr_encoded(1);
1307:
1308: while (my $token = $parser->get_token) {
1309: next if ($token->[0] ne 'S');
1310: if ($token->[1] eq 'param') {
1311: &parse_mapalias_param($token,$lpc, $hash);
1312: }
1313: }
1314:
1315: }
1316:
1317:
1318: #
1319: # Load a map from file into a target hash. This is done by first parsing the
1320: # map file into local hashes and then unrolling those hashes into the big hash.
1321: #
1322: # Parameters:
1323: #
1324: # $cnum - number of course being read.
1325: # $cdom - Domain in which the course is evaluated.
1326: # $uname - Name of the user for whom the course is being read
1327: # $udom - Name of the domain of the user for whom the course is being read.
1328: # $target_hash- Reference to the target hash into which all of this is read.
1329: # Note tht some of the hash entries we need to build require knowledge of the
1330: # course URI.. these are expected to be filled in by the caller.
1331: #
1332: # Errors are logged to lonnet and are managed via the Perl structured exception package.
1333: #
1334: #
1335: sub loadmap {
1336: my ($cnum, $cdom, $uname, $udom, $filepath, $target_hash) = @_;
1337:
1338: # Clear the auxillary hashes and the cond array.
1339:
1340:
1341: %randompick = ();
1342: %randompickseed = ();
1343: %encurl = ();
1344: %hiddenurl = ();
1345: @cond = ();
1346:
1347: #
1348:
1349: $username = $uname;
1350: $userdomain = $udom;
1351:
1352: my $short_name = $cdom . $cnum;
1353:
1354: try {
1355:
1356:
1357: # Get the information we need about the course.
1358: # Return without filling in anything if we can't get any info:
1359:
1360: my %cenv = &Apache::lonnet::coursedesription($short_name,
1361: {'freshen_cache' => 1,
1362: 'user' => $uname});
1363: unless ($cenv{'url'}) {
1364: &Apache::lonnet::logthis("lonmap::loadmap failed: $cnum/$cdom - did not get url");
1365: return;
1366: }
1367: $course_id = $cdom . '.' . $cnum; # Long course id.
1368:
1369: # Load the version information into the hash
1370:
1371:
1372: &process_versions(\%cenv, $target_hash);
1373:
1374:
1375: # Figure out the map filename's URI, and set up some starting points for the map.
1376:
1377: $course_uri = $cenv->{'url'};
1378: $map_uri = &Apache::lonnet::clutter($course_uri);
1379:
1380: $target_hash->{'src_0.0'} = &versiontrack($map_uri, $target_hash);
1381: $target_hash->{'title_0.0'} = &Apache::lonnet::metadata($course_uri, 'title');
1382: $target_hash->{'ids_'.$file_map_uri} = '0.0';
1383: $target_hash->{'is_map_0.0'} = 1;
1384: &read_map($course_uri, '0.0', &hash);
1385:
1386: #
1387:
1388: if (defined($hash->{'map_start_'.$uri})) {
1389:
1390: &traceroute('0',$hash->{'map_start_'.$course_uri},'&', $hash);
1391: &accinit($course_uri, $short_name, $fn, $hash);
1392: &hiddenurls($hash);
1393: }
1394:
1395: # Merge in the child hashes in case the caller wants that information as well.
1396:
1397:
1398: &merge_hash($hash, 'randompick', \%randompick);
1399: &merge_hash($hash, 'randompickseed', \%randompick);
1400: &merge_hash($hash, 'randomorder', \%randomorder);
1401: &merge_hash($hash, 'encurl', \%encurl);
1402: &merge_hash($hash, 'hiddenurl', \%hiddenurl);
1403: &merge_conditions($hash);
1404: }
1405: otherwise {
1406: my $e = shift;
1407: &Apache::lonnet::logthis("lonmap::loadmap failed: " . $e->stringify());
1408: }
1409:
1410: }
1411:
1412:
1413: 1;
1414:
1415: #
1416: # Module initialization code:
1417: #
1418:
1419: 1;
1420: __END__
1421:
1422: =head1 NAME
1423:
1424: Apache::lonmap - Construct a hash that represents a course (Big Hash).
1425:
1426: =head1 SYNOPSIS
1427:
1428: &Apache::lonmap::loadmap($filepath, \%target_hash);
1429:
1430: =head1 INTRODUCTION
1431:
1432: This module reads a course filename into a hash reference. It's up to the caller
1433: to to things like decide the has should be tied to some external file and handle the locking
1434: if this file should be shared amongst several Apache children.
1435:
1436: =head1 SUBROUTINES
1437:
1438: =over
1439:
1440: =item loadmap($filepath, $targethash)
1441:
1442:
1443: Reads the map file into a target hash.
1444:
1445: =over
1446:
1447: =item $filepath - The path to the map file to read.
1448:
1449: =item $targethash - A reference to hash into which the course is read.
1450:
1451: =back
1452:
1453: =item process_versions($cenv, $hash)
1454:
1455: Makes hash entries for each version of a course described by a course environment
1456: returned from Apache::lonnet::coursedescription.
1457:
1458: =over
1459:
1460: =item $cenv - Reference to the environment hash returned by Apache::lonnet::coursedescription
1461:
1462: =item $hash - Hash to be filled in with 'version_xxx' entries as per the big hash.
1463:
1464: =back
1465:
1466: =back
1467:
1468:
1469: =cut
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