--- rat/lonuserstate.pm 2011/07/26 10:40:23 1.138 +++ rat/lonuserstate.pm 2011/08/04 10:57:26 1.139 @@ -1,7 +1,7 @@ # The LearningOnline Network with CAPA # Construct and maintain state and binary representation of course for user # -# $Id: lonuserstate.pm,v 1.138 2011/07/26 10:40:23 foxr Exp $ +# $Id: lonuserstate.pm,v 1.139 2011/08/04 10:57:26 foxr Exp $ # # Copyright Michigan State University Board of Trustees # @@ -70,6 +70,21 @@ sub versionerror { $uri,$usedversion,$unusedversion).'
'; } +# Removes the version number from a URI and returns the resulting +# URI (e.g. mumbly.version.stuff => mumbly.stuff). +# +# If the URI has not been seen with a versio before the +# hash{'version_'.resultingURI} is set to the version number. +# If the URI has been seen and the version does not match and error +# is added to the error string. +# +# Parameters: +# URI potentially with a version. +# Returns: +# URI with the version cut out. +# See above for side effects. +# + sub versiontrack { my $uri=shift; if ($uri=~/\.(\d+)\.\w+$/) { @@ -218,7 +233,7 @@ sub loadmap { if ($token->[1] eq 'resource') { my $resource_id = &parse_resource($token,$lpc,$ispage,$uri); if (defined $resource_id) { - push(@map_ids, $resource_id); + push(@map_ids, $resource_id); } # Link @@ -226,7 +241,7 @@ sub loadmap { } elsif ($token->[1] eq 'link' && !$randomize) { &make_link(++$linkpc,$lpc,$token->[2]->{'to'}, $token->[2]->{'from'}, - $token->[2]->{'condition'}); + $token->[2]->{'condition'}); # note ..condition may be undefined. # condition @@ -241,9 +256,17 @@ sub loadmap { if ($randomize) { if (!$env{'request.role.adv'}) { my $seed; + + # In the advanced role, the map's random seed + # parameter is used as the basis for computing the + # seed ... if it has been specified: + if (defined($randompickseed{$parent_rid})) { $seed = $randompickseed{$parent_rid}; } else { + + # Otherwise the parent's fully encoded symb is used. + my ($mapid,$resid)=split(/\./,$parent_rid); my $symb= &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid}, @@ -252,18 +275,26 @@ sub loadmap { $seed = $symb; } - # Here for sure we need to pass along the username/domain + # TODO: Here for sure we need to pass along the username/domain # so that we can impersonate users in lonprintout e.g. my $rndseed=&Apache::lonnet::rndseed($seed); &Apache::lonnet::setup_random_from_rndseed($rndseed); - @map_ids=&Math::Random::random_permutation(@map_ids); + @map_ids=&math::Random::random_permutation(@map_ids); # randomorder. } + + my $from = shift(@map_ids); my $from_rid = $lpc.'.'.$from; $hash{'map_start_'.$uri} = $from_rid; $hash{'type_'.$from_rid}='start'; + # Create links to reflect this random ordering. + # BUG? If there are conditions, this invalidates them? Then again + # with randompick there's no gaurentee the resources required for the + # conditinos to work will be selected into the map. + # so randompick is inconsistent with a map that has conditions? + while (my $to = shift(@map_ids)) { &make_link(++$linkpc,$lpc,$to,$from); my $to_rid = $lpc.'.'.$to; @@ -278,8 +309,10 @@ sub loadmap { $parser = HTML::TokeParser->new(\$instr); $parser->attr_encoded(1); + # last parse out the mapalias params so as to ignore anything # refering to non-existant resources + while (my $token = $parser->get_token) { next if ($token->[0] ne 'S'); if ($token->[1] eq 'param') { @@ -305,6 +338,7 @@ sub loadmap { # $ispage - True if this resource is encapsulated in a .page (assembled resourcde). # $uri - URI of the enclosing resource. # Returns: +# Value of the id attribute of the tag. # # Note: # The token is an array that contains the following elements: @@ -325,10 +359,14 @@ sub loadmap { sub parse_resource { my ($token,$lpc,$ispage,$uri) = @_; - # I refuse to coutenance code like this that has + # I refuse to countenance code like this that has # such a dirty side effect (and forcing this sub to be called within a loop). # # if ($token->[2]->{'type'} eq 'zombie') { next; } + # + # The original code both returns _and_ skips to the next pass of the >caller's< + # loop, that's just dirty. + # # Zombie resources don't produce anything useful. @@ -336,22 +374,38 @@ sub parse_resource { return undef; } - my $rid=$lpc.'.'.$token->[2]->{'id'}; + my $rid=$lpc.'.'.$token->[2]->{'id'}; # Resource id in hash is levelcounter.id-in-xml. + + # Save the hash element type and title: $hash{'kind_'.$rid}='res'; $hash{'title_'.$rid}=$token->[2]->{'title'}; + + # Get the version free URI for the resource. + # If a 'version' attribute was supplied, and this resource's version + # information has not yet been stored, store it. + # + my $turi=&versiontrack($token->[2]->{'src'}); if ($token->[2]->{'version'}) { unless ($hash{'version_'.$turi}) { $hash{'version_'.$turi}=$1; } } + # Pull out the title and do entity substitution on &colon + # Q: Why no other entity substitutions? + my $title=$token->[2]->{'title'}; $title=~s/\&colon\;/\:/gs; -# my $symb=&Apache::lonnet::encode_symb($uri, -# $token->[2]->{'id'}, -# $turi); -# &Apache::lonnet::do_cache_new('title',$symb,$title); + + + + # I think the point of all this code is to construct a final + # URI that apache and its rewrite rules can use to + # fetch the resource. Thi s sonly necessary if the resource + # is not a page. If the resource is a page then it must be + # assembled (at fetch time?). + unless ($ispage) { $turi=~/\.(\w+)$/; my $embstyle=&Apache::loncommon::fileembstyle($1); @@ -378,7 +432,10 @@ sub parse_resource { } } } -# Store reverse lookup, remove query string + # Store reverse lookup, remove query string resource 'ids'_uri => resource id. + # If the URI appears more than one time in the sequence, it's resourcde + # id's are constructed as a comma spearated list. + my $idsuri=$turi; $idsuri=~s/\?.+$//; if (defined($hash{'ids_'.$idsuri})) { @@ -387,17 +444,37 @@ sub parse_resource { $hash{'ids_'.$idsuri}=''.$rid; } + + if ($turi=~/\/(syllabus|aboutme|navmaps|smppg|bulletinboard|viewclasslist)$/) { $turi.='?register=1'; } + + # resource id lookup: 'src'_resourc-di => URI decorated with a query + # parameter as above if necessary due to the resource type. + $hash{'src_'.$rid}=$turi; + + # Mark the external-ness of the resource: if ($token->[2]->{'external'} eq 'true') { $hash{'ext_'.$rid}='true:'; } else { $hash{'ext_'.$rid}='false:'; } + + # If the resource is a start/finish resource set those + # entries in the has so that navigation knows where everything starts. + # TODO? If there is a malformed sequence that has no start or no finish + # resource, should this be detected and errors thrown? How would such a + # resource come into being other than being manually constructed by a person + # and then uploaded? Could that happen if an author decided a sequence was almost + # right edited it by hand and then reuploaded it to 'fix it' but accidently cut the + # start or finish resources? + # + # All resourcess also get a type_id => (start | finish | normal) hash entr. + # if ($token->[2]->{'type'}) { $hash{'type_'.$rid}=$token->[2]->{'type'}; if ($token->[2]->{'type'} eq 'start') { @@ -409,6 +486,12 @@ sub parse_resource { } else { $hash{'type_'.$rid}='normal'; } + + # Sequences end pages are constructed entities. They require that the + # map that defines _them_ be loaded as well into the hash...with this resourcde + # as the base of the nesting. + # Resources like that are also marked with is_map_id => 1 entries. + # if (($turi=~/\.sequence$/) || ($turi=~/\.page$/)) { @@ -418,22 +501,65 @@ sub parse_resource { return $token->[2]->{'id'}; } +#-------------------------------------------------------------------- link +# Links define how you are allowed to move from one resource to another. +# They are the transition edges in the directed graph that a map is. +# This sub takes informatino from a tag and constructs the +# navigation bits and pieces of a map. There is no requirement that the +# resources that are linke are already defined, however clearly the map is +# badly broken if they are not _eventually_ defined. +# +# Note that links can be unconditional or conditional. +# +# Parameters: +# linkpc - The link counter for this level of map nesting (this is +# reset to zero by loadmap prior to starting to process +# links for map). +# lpc - The map level ocounter (how deeply nested this map is in +# the hierarchy of maps that are recursively read in. +# to - resource id (within the XML) of the target of the edge. +# from - resource id (within the XML) of the source of the edge. +# condition- id of condition associated with the edge (also within the XML). +# + sub make_link { my ($linkpc,$lpc,$to,$from,$condition) = @_; + # Compute fully qualified ids for the link, the + # and from/to by prepending lpc. + # + my $linkid=$lpc.'.'.$linkpc; my $goesto=$lpc.'.'.$to; my $comesfrom=$lpc.'.'.$from; my $undercond=0; + + # If there is a condition, qualify it with the level counter. + if ($condition) { $undercond=$lpc.'.'.$condition; } + # Links are represnted by: + # goesto_.fuullyqualifedlinkid => fully qualified to + # comesfrom.fullyqualifiedlinkid => fully qualified from + # undercond_.fullyqualifiedlinkid => fully qualified condition id. + $hash{'goesto_'.$linkid}=$goesto; $hash{'comesfrom_'.$linkid}=$comesfrom; $hash{'undercond_'.$linkid}=$undercond; + # In addition: + # to_.fully qualified from => comma separated list of + # link ids with that from. + # Similarly: + # from_.fully qualified to => comma separated list of link ids` + # with that to. + # That allows us given a resource id to know all edges that go to it + # and leave from it. + # + if (defined($hash{'to_'.$comesfrom})) { $hash{'to_'.$comesfrom}.=','.$linkid; } else { @@ -447,6 +573,54 @@ sub make_link { } # ------------------------------------------------------------------- Condition +# +# Processes tags, storing sufficient information about them +# in the hash so that they can be evaluated and used to conditionalize +# what is presented to the student. +# +# these can have the following attributes +# +# id = A unique identifier of the condition within the map. +# +# value = Is a perl script-let that, when evaluated in safe space +# determines whether or not the condition is true. +# Normally this takes the form of a test on an Apache::lonnet::EXT call +# to find the value of variable associated with a resource in the +# map identified by a mapalias. +# Here's a fragment of XML code that illustrates this: +# +# +# +# +# +# +# +# In this fragment: +# - The param tag establishes an alias to resource id 5 of 'mainproblem'. +# - The resource that is the start of the map is identified. +# - The resource tag identifies the resource associated with this tag +# and gives it the id 5. +# - The condition is true if the tries variable associated with mainproblem +# is less than 2 (that is the user has had more than 2 tries). +# The condition type is a stop condition which inhibits(?) the associated +# link if the condition is false. +# - The link to resource 5 from resource 1 is affected by this condition. +# +# type = Type of the condition. The type determines how the condition affects the +# link associated with it and is one of +# - 'force' +# - 'stop' +# anything else including not supplied..which treated as: +# - 'normal'. +# Presumably maps get created by the resource assembly tool and therefore +# illegal type values won't squirm their way into the XML. +# +# Side effects: +# - The kind_level-qualified-condition-id hash element is set to 'cond'. +# - The condition text is pushed into the cond array and its element number is +# set in the condid_level-qualified-condition-id element of the hash. +# - The condition type is colon appneded to the cond array element for this condition. sub parse_condition { my ($token,$lpc) = @_; my $rid=$lpc.'.'.$token->[2]->{'id'};