--- loncom/interface/lonhelper.pm 2003/05/07 18:13:13 1.20 +++ loncom/interface/lonhelper.pm 2003/05/12 19:33:57 1.27 @@ -1,7 +1,7 @@ # The LearningOnline Network with CAPA # .helper XML handler to implement the LON-CAPA helper # -# $Id: lonhelper.pm,v 1.20 2003/05/07 18:13:13 bowersj2 Exp $ +# $Id: lonhelper.pm,v 1.27 2003/05/12 19:33:57 bowersj2 Exp $ # # Copyright Michigan State University Board of Trustees # @@ -193,10 +193,38 @@ my $substate; # end of the element tag is located. my $paramHash; +# Note from Jeremy 5-8-2003: It is *vital* that the real handler be called +# as a subroutine from the handler, or very mysterious things might happen. +# I don't know exactly why, but it seems that the scope where the Apache +# server enters the perl handler is treated differently from the rest of +# the handler. This also seems to manifest itself in the debugger as entering +# the perl handler in seemingly random places (sometimes it starts in the +# compiling phase, sometimes in the handler execution phase where it runs +# the code and stepping into the "1;" the module ends with goes into the handler, +# sometimes starting directly with the handler); I think the cause is related. +# In the debugger, this means that breakpoints are ignored until you step into +# a function and get out of what must be a "faked up scope" in the Apache-> +# mod_perl connection. In this code, it was manifesting itself in the existence +# of two seperate file-scoped $helper variables, one set to the value of the +# helper in the helper constructor, and one referenced by the handler on the +# "$helper->process()" line. The second was therefore never set, and was still +# undefined when I tried to call process on it. +# By pushing the "real handler" down into the "real scope", everybody except the +# actual handler function directly below this comment gets the same $helper and +# everybody is happy. +# The upshot of all of this is that for safety when a handler is using +# file-scoped variables in LON-CAPA, the handler should be pushed down one +# call level, as I do here, to ensure that the top-level handler function does +# not get a different file scope from the rest of the code. +sub handler { + my $r = shift; + return real_handler($r); +} + # For debugging purposes, one can send a second parameter into this # function, the 'uri' of the helper you wish to have rendered, and # call this from other handlers. -sub handler { +sub real_handler { my $r = shift; my $uri = shift; if (!defined($uri)) { $uri = $r->uri(); } @@ -206,6 +234,7 @@ sub handler { my $file; read $fh, $file, 100000000; + # Send header, don't cache this page if ($r->header_only) { if ($ENV{'browser.mathml'}) { @@ -315,6 +344,8 @@ sub new { $self->{TITLE} = shift; + Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING}); + # If there is a state from the previous form, use that. If there is no # state, use the start state parameter. if (defined $ENV{"form.CURRENT_STATE"}) @@ -326,8 +357,6 @@ sub new { $self->{STATE} = "START"; } - Apache::loncommon::get_unprocessed_cgi($ENV{QUERY_STRING}); - $self->{TOKEN} = $ENV{'form.TOKEN'}; # If a token was passed, we load that in. Otherwise, we need to create a # new storage file @@ -690,11 +719,38 @@ the helper variables, like this: =back +B + +Each element can contain a "finalcode" tag that, when the special FINAL +helper state is used, will be executed, surrounded by "sub { my $helper = shift;" +and "}". It is expected to return a string describing what it did, which +may be an empty string. See course initialization helper for an example. This is +generally intended for helpers like the course initialization helper, which consist +of several panels, each of which is performing some sort of bite-sized functionality. + +B + +Each element that accepts user input can contain a "defaultvalue" tag that, +when surrounded by "sub { my $helper = shift; my $state = shift; " and "}", +will form a subroutine that when called will provide a default value for +the element. How this value is interpreted by the element is specific to +the element itself, and possibly the settings the element has (such as +multichoice vs. single choice for tags). + +This is also intended for things like the course initialization wizard, where the +user is setting various parameters. By correctly grabbing current settings +and including them into the helper, it allows the user to come back to the +helper later and re-execute it, without needing to worry about overwriting +some setting accidentally. + +Again, see the course initialization helper for examples. + =cut BEGIN { &Apache::lonhelper::register('Apache::lonhelper::element', - ('nextstate')); + ('nextstate', 'finalcode', + 'defaultvalue')); } # Because we use the param hash, this is often a sufficent @@ -729,6 +785,36 @@ sub start_nextstate { sub end_nextstate { return ''; } +sub start_finalcode { + my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_; + + if ($target ne 'helper') { + return ''; + } + + $paramHash->{FINAL_CODE} = &Apache::lonxml::get_all_text('/finalcode', + $parser); + return ''; +} + +sub end_finalcode { return ''; } + +sub start_defaultvalue { + my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_; + + if ($target ne 'helper') { + return ''; + } + + $paramHash->{DEFAULT_VALUE} = &Apache::lonxml::get_all_text('/defaultvalue', + $parser); + $paramHash->{DEFAULT_VALUE} = 'sub { my $helper = shift; my $state = shift;' . + $paramHash->{DEFAULT_VALUE} . '}'; + return ''; +} + +sub end_defaultvalue { return ''; } + sub preprocess { return 1; } @@ -875,6 +961,10 @@ the result is stored in. takes an attribute "multichoice" which, if set to a true value, will allow the user to select multiple choices. + takes an attribute "allowempty" which, if set to a true +value, will allow the user to select none of the choices without raising +an error message. + B can have the following subtags: @@ -924,6 +1014,18 @@ You can mix and match methods of creatin "push" onto the choice list, rather then wiping it out. (You can even remove choices programmatically, but that would probably be bad form.) +B + +Choices supports default values both in multichoice and single choice mode. +In single choice mode, have the defaultvalue tag's function return the +computer value of the box you want checked. If the function returns a value +that does not correspond to any of the choices, the default behavior of selecting +the first choice will be preserved. + +For multichoice, return a string with the computer values you want checked, +delimited by triple pipes. Note this matches how the result of the +tag is stored in the {VARS} hash. + =cut no strict; @@ -949,9 +1051,10 @@ sub start_choices { } # Need to initialize the choices list, so everything can assume it exists - $paramHash->{'variable'} = $token->[2]{'variable'}; + $paramHash->{'variable'} = $token->[2]{'variable'} if (!defined($paramHash->{'variable'})); $helper->declareVar($paramHash->{'variable'}); $paramHash->{'multichoice'} = $token->[2]{'multichoice'}; + $paramHash->{'allowempty'} = $token->[2]{'allowempty'}; $paramHash->{CHOICES} = []; return ''; } @@ -1007,6 +1110,11 @@ sub render { } SCRIPT + } + + # Only print "select all" and "unselect all" if there are five or + # more choices; fewer then that and it looks silly. + if ($self->{'multichoice'} && scalar(@{$self->{CHOICES}}) > 4) { $buttons = < @@ -1023,18 +1131,52 @@ BUTTONS $result .= "\n\n"; + my %checkedChoices; + my $checkedChoicesFunc; + + if (defined($self->{DEFAULT_VALUE})) { + $checkedChoicesFunc = eval ($self->{DEFAULT_VALUE}); + die 'Error in default value code for variable ' . + {'variable'} . ', Perl said:' . $@ if $@; + } else { + $checkedChoicesFunc = sub { return ''; }; + } + + # Process which choices should be checked. + if ($self->{'multichoice'}) { + for my $selectedChoice (split(/\|\|\|/, (&$checkedChoicesFunc($helper, $self)))) { + $checkedChoices{$selectedChoice} = 1; + } + } else { + # single choice + my $selectedChoice = &$checkedChoicesFunc($helper, $self); + + my $foundChoice = 0; + + # check that the choice is in the list of choices. + for my $choice (@{$self->{CHOICES}}) { + if ($choice->[1] eq $selectedChoice) { + $checkedChoices{$choice->[1]} = 1; + $foundChoice = 1; + } + } + + # If we couldn't find the choice, pick the first one + if (!$foundChoice) { + $checkedChoices{$self->{CHOICES}->[0]->[1]} = 1; + } + } + my $type = "radio"; if ($self->{'multichoice'}) { $type = 'checkbox'; } - my $checked = 0; foreach my $choice (@{$self->{CHOICES}}) { $result .= "\n\n"; $result .= "
 {'multichoice'} && !$checked) { + if ($checkedChoices{$choice->[1]}) { $result .= " checked "; - $checked = 1; } my $choiceLabel = $choice->[0]; if ($choice->[4]) { # if we need to evaluate this choice @@ -1057,7 +1199,7 @@ sub postprocess { my $self = shift; my $chosenValue = $ENV{'form.' . $self->{'variable'} . '.forminput'}; - if (!$chosenValue) { + if (!defined($chosenValue) && !$self->{'allowempty'}) { $self->{ERROR_MSG} = "You must choose one or more choices to" . " continue."; return 0; @@ -1835,6 +1977,10 @@ sub render { my $filterFunc = $self->{FILTER_FUNC}; my $buttons = ''; + my $type = 'radio'; + if ($self->{'multichoice'}) { + $type = 'checkbox'; + } if ($self->{'multichoice'}) { $result = < SCRIPT $buttons = <   +BUTTONS + + if ($helper->{VARS}->{'construction'}) { + $buttons .= < +
  BUTTONS + } } # Get the list of files in this directory. @@ -1881,10 +2043,6 @@ BUTTONS # Keeps track if there are no choices, prints appropriate error # if there are none. my $choices = 0; - my $type = 'radio'; - if ($self->{'multichoice'}) { - $type = 'checkbox'; - } # Print each legitimate file choice. for my $file (@fileList) { $file = (split(/&/, $file))[0]; @@ -1893,9 +2051,36 @@ BUTTONS } my $fileName = $subdir .'/'. $file; if (&$filterFunc($file)) { - (my $status, my $color) = @{fileState($subdir, $file)}; + my $status; + my $color; + if ($helper->{VARS}->{'construction'}) { + ($status, $color) = @{fileState($subdir, $file)}; + } else { + $status = ''; + $color = ''; + } + + # Netscape 4 is stupid and there's nowhere to put the + # information on the input tag that the file is Published, + # Unpublished, etc. In *real* browsers we can just say + # "class='Published'" and check the className attribute of + # the input tag, but Netscape 4 is too stupid to understand + # that attribute, and un-comprehended attributes are not + # reflected into the object model. So instead, what I do + # is either have or don't have an "onclick" handler that + # does nothing, give Published files the onclick handler, and + # have the checker scripts check for that. Stupid and clumsy, + # and only gives us binary "yes/no" information (at least I + # couldn't figure out how to reach into the event handler's + # actual code to retreive a value), but it works well enough + # here. + + my $onclick = ''; + if ($status eq 'Published' && $helper->{VARS}->{'construction'}) { + $onclick = 'onclick="a=1" '; + } $result .= '
" . - "{'multichoice'} && $choices == 0) { @@ -2178,6 +2363,101 @@ sub end_eval { 1; +package Apache::lonhelper::final; + +=pod + +=head2 Element: final + + is a special element that works with helpers that use the +tag. It goes through all the states and elements, executing the +snippets and collecting the results. Finally, it takes the user out of the +helper, going to a provided page. + +=cut + +no strict; +@ISA = ("Apache::lonhelper::element"); +use strict; + +BEGIN { + &Apache::lonhelper::register('Apache::lonhelper::final', + ('final', 'exitpage')); +} + +sub new { + my $ref = Apache::lonhelper::element->new(); + bless($ref); +} + +sub start_final { return ''; } + +sub end_final { + my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_; + + if ($target ne 'helper') { + return ''; + } + + Apache::lonhelper::final->new(); + + return ''; +} + +sub start_exitpage { + my ($target,$token,$tagstack,$parstack,$parser,$safeeval,$style)=@_; + + if ($target ne 'helper') { + return ''; + } + + $paramHash->{EXIT_PAGE} = &Apache::lonxml::get_all_text('/exitpage', + $parser); + + return ''; +} + +sub end_exitpage { return ''; } + +sub render { + my $self = shift; + + my @results; + + # Collect all the results + for my $stateName (keys %{$helper->{STATES}}) { + my $state = $helper->{STATES}->{$stateName}; + + for my $element (@{$state->{ELEMENTS}}) { + if (defined($element->{FINAL_CODE})) { + # Compile the code. + my $code = 'sub { my $helper = shift; ' . $element->{FINAL_CODE} . + '}'; + $code = eval($code); + die 'Error while executing final code for element with var ' . + $element->{'variable'} . ', Perl said: ' . $@ if $@; + + my $result = &$code($helper); + if ($result) { + push @results, $result; + } + } + } + } + + if (scalar(@results) == 0) { + return ''; + } + + my $result = "
    \n"; + for my $re (@results) { + $result .= '
  • ' . $re . "
    • \n"; + } + return $result . '
'; +} + +1; + package Apache::lonhelper::parmwizfinal; # This is the final state for the parmwizard. It is not generally useful, @@ -2225,60 +2505,72 @@ sub render { 'due_date' => "0_duedate", 'answer_date' => "0_answerdate"); - my $result = "
\n"; - $result .= '

Confirm that this information is correct, then click "Finish Wizard" to complete setting the parameter.

    '; my $affectedResourceId = ""; my $parm_name = $parmTypeHash{$vars->{ACTION_TYPE}}; my $level = ""; - - # Print the type of manipulation: - $result .= '
  • Setting the ' . $dateTypeHash{$vars->{ACTION_TYPE}} - . "
    • \n"; - if ($vars->{ACTION_TYPE} eq 'due_date' || - $vars->{ACTION_TYPE} eq 'answer_date') { - # for due dates, we default to "date end" type entries - $result .= "\n"; - $result .= "\n"; - $result .= "\n"; - } elsif ($vars->{ACTION_TYPE} eq 'open_date') { - $result .= "\n"; - $result .= "\n"; - $result .= "\n"; - } - + my $resourceString; + my $symb; + my $paramlevel; + # Print the granularity, depending on the action if ($vars->{GRANULARITY} eq 'whole_course') { - $result .= '
  • for all resources in the course
    • '; + $resourceString .= '
  • for all resources in the course
    • '; $level = 9; # general course, see lonparmset.pm perldoc $affectedResourceId = "0.0"; + $symb = 'a'; + $paramlevel = 'general'; } elsif ($vars->{GRANULARITY} eq 'map') { my $navmap = Apache::lonnavmaps::navmap->new( $ENV{"request.course.fn"}.".db", $ENV{"request.course.fn"}."_parms.db", 0, 0); my $res = $navmap->getById($vars->{RESOURCE_ID}); my $title = $res->compTitle(); + $symb = $res->symb(); $navmap->untieHashes(); - $result .= "
  • for the map named $title
    • "; + $resourceString .= "
  • for the map named $title
    • "; $level = 8; $affectedResourceId = $vars->{RESOURCE_ID}; + $paramlevel = 'map'; } else { my $navmap = Apache::lonnavmaps::navmap->new( $ENV{"request.course.fn"}.".db", $ENV{"request.course.fn"}."_parms.db", 0, 0); my $res = $navmap->getById($vars->{RESOURCE_ID}); + $symb = $res->symb(); my $title = $res->compTitle(); $navmap->untieHashes(); - $result .= "
  • for the resource named $title
    • "; + $resourceString .= "
  • for the resource named $title
    • "; $level = 7; $affectedResourceId = $vars->{RESOURCE_ID}; + $paramlevel = 'full'; } + my $result = "\n"; + $result .= '

    Confirm that this information is correct, then click "Finish Wizard" to complete setting the parameter.

      '; + + # Print the type of manipulation: + $result .= '
    • Setting the ' . $dateTypeHash{$vars->{ACTION_TYPE}} + . "
      • \n"; + if ($vars->{ACTION_TYPE} eq 'due_date' || + $vars->{ACTION_TYPE} eq 'answer_date') { + # for due dates, we default to "date end" type entries + $result .= "\n"; + $result .= "\n"; + $result .= "\n"; + } elsif ($vars->{ACTION_TYPE} eq 'open_date') { + $result .= "\n"; + $result .= "\n"; + $result .= "\n"; + } + + $result .= $resourceString; + # Print targets if ($vars->{TARGETS} eq 'course') { $result .= '
    • for all students in course
      • '; @@ -2291,7 +2583,10 @@ sub render { } else { # FIXME: This is probably wasteful! Store the name! my $classlist = Apache::loncoursedata::get_classlist(); - my $name = $classlist->{$vars->{USER_NAME}}->[6]; + my $username = $vars->{USER_NAME}; + # Chop off everything after the last colon (section) + $username = substr($username, 0, rindex($username, ':')); + my $name = $classlist->{$username}->[6]; $result .= "
    • for $name
      • "; $level -= 6; my ($uname, $udom) = split /:/, $vars->{USER_NAME}; @@ -2309,6 +2604,12 @@ sub render { # print pres_marker $result .= "\n\n"; + + # Make the table appear + $result .= "\n"; + $result .= "\n"; + $result .= "\n"; + $result .= "\n"; $result .= "

      \n";