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Original Path: trunk/webwork2/lib/WeBWorK/ContentGenerator.pm
| 1 : | sh002i | 455 | ################################################################################ |
| 2 : | sh002i | 494 | # WeBWorK mod_perl (c) 2000-2002 WeBWorK Project |
| 3 : | sh002i | 455 | # $Id$ |
| 4 : | ################################################################################ | ||
| 5 : | |||
| 6 : | malsyned | 313 | package WeBWorK::ContentGenerator; |
| 7 : | malsyned | 305 | |
| 8 : | sh002i | 455 | =head1 NAME |
| 9 : | |||
| 10 : | WeBWorK::ContentGenerator - base class for modules that generate page content. | ||
| 11 : | |||
| 12 : | =cut | ||
| 13 : | |||
| 14 : | malsyned | 441 | use strict; |
| 15 : | use warnings; | ||
| 16 : | malsyned | 323 | use Apache::Constants qw(:common); |
| 17 : | sh002i | 455 | use CGI qw(); |
| 18 : | sh002i | 469 | use URI::Escape; |
| 19 : | sh002i | 526 | use WeBWorK::DB::Auth; |
| 20 : | sh002i | 476 | use WeBWorK::Utils qw(readFile); |
| 21 : | sh002i | 555 | use Carp qw(cluck); |
| 22 : | malsyned | 390 | |
| 23 : | sh002i | 469 | ################################################################################ |
| 24 : | # This is a very unruly file, so I'm going to use very large comments to divide | ||
| 25 : | # it into logical sections. | ||
| 26 : | ################################################################################ | ||
| 27 : | malsyned | 390 | |
| 28 : | sh002i | 469 | # new(Apache::Request, WeBWorK::CourseEnvironment) - create a new instance of a |
| 29 : | # content generator. Usually only called by the dispatcher, although one might | ||
| 30 : | # be able to use it for things like "sub-requests". Uh... uh... I have to think | ||
| 31 : | # about that one. The dispatcher uses this idiom: | ||
| 32 : | # | ||
| 33 : | # | ||
| 34 : | # WeBWorK::ContentGenerator::WHATEVER->new($r, $ce)->go(@whatever); | ||
| 35 : | # | ||
| 36 : | # and throws away the result ;) | ||
| 37 : | # | ||
| 38 : | malsyned | 305 | sub new($$$) { |
| 39 : | malsyned | 323 | my $invocant = shift; |
| 40 : | my $class = ref($invocant) || $invocant; | ||
| 41 : | malsyned | 305 | my $self = {}; |
| 42 : | ($self->{r}, $self->{courseEnvironment}) = @_; | ||
| 43 : | bless $self, $class; | ||
| 44 : | return $self; | ||
| 45 : | } | ||
| 46 : | |||
| 47 : | sh002i | 469 | ################################################################################ |
| 48 : | # Invocation and template processing | ||
| 49 : | ################################################################################ | ||
| 50 : | malsyned | 323 | |
| 51 : | sh002i | 469 | # go(@otherArguments) - render a page, using methods from the particular |
| 52 : | # subclass of ContentGenerator. @otherArguments is passed to each method, so | ||
| 53 : | # that the dispatcher can pass CG-specific data. The order of calls looks like | ||
| 54 : | # this: | ||
| 55 : | # | ||
| 56 : | # * &pre_header_initialize - give subclasses a chance to do initialization | ||
| 57 : | # necessary for generating the HTTP header. | ||
| 58 : | # * &header - this class provides a standard HTTP header with Content-Type | ||
| 59 : | # text/html. Subclasses are welcome to overload this for things like | ||
| 60 : | # an image-creation content generator or a PDF generator. | ||
| 61 : | # * &initialize - let subclasses do post-header initialization. | ||
| 62 : | # * any "template escapes" defined in the system template and supported by | ||
| 63 : | # the subclass. Generic implementations of &title and &body are provided. | ||
| 64 : | # | ||
| 65 : | sub go { | ||
| 66 : | my $self = shift; | ||
| 67 : | my $r = $self->{r}; | ||
| 68 : | my $courseEnvironment = $self->{courseEnvironment}; | ||
| 69 : | |||
| 70 : | $self->pre_header_initialize(@_) if $self->can("pre_header_initialize"); | ||
| 71 : | $self->header(@_); | ||
| 72 : | return OK if $r->header_only; | ||
| 73 : | malsyned | 313 | |
| 74 : | sh002i | 469 | $self->initialize(@_) if $self->can("initialize"); |
| 75 : | $self->template($courseEnvironment->{templates}->{system}, @_); | ||
| 76 : | malsyned | 441 | |
| 77 : | sh002i | 469 | return OK; |
| 78 : | } | ||
| 79 : | |||
| 80 : | # template(STRING, @otherArguments) - parse a template, looking for escapes of | ||
| 81 : | # the form <!--#NAME ARG1="FOO" ARG2="BAR"--> and calling a member function NAME | ||
| 82 : | # (if available) for each NAME. The escapes are called like: | ||
| 83 : | # | ||
| 84 : | # $self->NAME(@otherArguments, \%escapeArguments) | ||
| 85 : | # | ||
| 86 : | # where @otherArguments originates in the dispatcher and %escapeArguments is | ||
| 87 : | # parsed out of the escape itself (i.e. ARG1 => FOO, ARG2 => BAR) | ||
| 88 : | # | ||
| 89 : | sub template { | ||
| 90 : | my ($self, $templateFile) = (shift, shift); | ||
| 91 : | my $r = $self->{r}; | ||
| 92 : | my $courseEnvironment = $self->{courseEnvironment}; | ||
| 93 : | malsyned | 512 | my @ifstack = (1); # Start off in printing mode |
| 94 : | # say $ifstack[-1] to get the result of the last <#!--if--> | ||
| 95 : | sh002i | 469 | |
| 96 : | sh002i | 476 | # so even though the variable $/ APPEARS to contain a newline, |
| 97 : | # <TEMPLATE> is slurping the whole file into the first element of | ||
| 98 : | # @template ONLY AFTER THE TRANSLATOR RUNS. WTF!!! | ||
| 99 : | # | ||
| 100 : | #open(TEMPLATE, $templateFile) or die "Couldn't open template $templateFile"; | ||
| 101 : | #my @template = <TEMPLATE>; | ||
| 102 : | #close TEMPLATE; | ||
| 103 : | # | ||
| 104 : | # Let's try something else instead: | ||
| 105 : | my @template = split /\n/, readFile($templateFile); | ||
| 106 : | |||
| 107 : | sh002i | 469 | foreach my $line (@template) { |
| 108 : | # This is incremental regex processing. | ||
| 109 : | # the /c is so that pos($line) doesn't die when the regex fails. | ||
| 110 : | while ($line =~ m/\G(.*?)<!--#(\w*)((?:\s+.*?)?)-->/gc) { | ||
| 111 : | my ($before, $function, $raw_args) = ($1, $2, $3); | ||
| 112 : | sh002i | 555 | my @args = ($raw_args =~ /\S/) ? cook_args($raw_args) : (); |
| 113 : | |||
| 114 : | malsyned | 512 | if ($ifstack[-1]) { |
| 115 : | print $before; | ||
| 116 : | } | ||
| 117 : | sh002i | 555 | |
| 118 : | malsyned | 633 | warn '$function undefined' if !defined $function; |
| 119 : | warn '@ifstack undefined' if !defined @ifstack; | ||
| 120 : | warn '@args undefined' if !defined @args; | ||
| 121 : | |||
| 122 : | sh002i | 558 | if ($function eq "if") { |
| 123 : | push @ifstack, $self->$function(@_, [@args]); | ||
| 124 : | } elsif ($function eq "else" and @ifstack > 1) { | ||
| 125 : | $ifstack[-1] = not $ifstack[-1]; | ||
| 126 : | } elsif ($function eq "endif" and @ifstack > 1) { | ||
| 127 : | pop @ifstack; | ||
| 128 : | } elsif ($ifstack[-1]) { | ||
| 129 : | sh002i | 562 | if ($self->can($function)) { |
| 130 : | print $self->$function(@_, {@args}); | ||
| 131 : | } | ||
| 132 : | sh002i | 476 | } |
| 133 : | malsyned | 313 | } |
| 134 : | sh002i | 469 | |
| 135 : | malsyned | 512 | if ($ifstack[-1]) { |
| 136 : | sh002i | 562 | print substr($line, (defined pos $line) ? pos $line : 0), "\n"; |
| 137 : | malsyned | 512 | } |
| 138 : | malsyned | 313 | } |
| 139 : | sh002i | 469 | } |
| 140 : | |||
| 141 : | # cook_args(STRING) - parses a string of the form ARG1="FOO" ARG2="BAR". Returns | ||
| 142 : | malsyned | 512 | # a list which pairs into key/values and fits nicely in {}s. |
| 143 : | sh002i | 469 | # |
| 144 : | sub cook_args($) { | ||
| 145 : | my ($raw_args) = @_; | ||
| 146 : | malsyned | 512 | my @args = (); |
| 147 : | malsyned | 353 | |
| 148 : | malsyned | 508 | # Boy I love m//g in scalar context! Go read the camel book, heathen. |
| 149 : | # First, get the whole token with the quotes on both ends... | ||
| 150 : | while ($raw_args =~ m/\G\s*(\w*)="((?:[^"\\]|\\.)*)"/g) { | ||
| 151 : | my ($key, $value) = ($1, $2); | ||
| 152 : | # ... then, rip out all the protecty backspaces | ||
| 153 : | malsyned | 522 | $value =~ s/\\(.)/$1/g; |
| 154 : | malsyned | 512 | push @args, $key => $value; |
| 155 : | sh002i | 469 | } |
| 156 : | |||
| 157 : | malsyned | 512 | return @args; |
| 158 : | malsyned | 313 | } |
| 159 : | |||
| 160 : | sh002i | 558 | # This is different. It probably shouldn't print anything (except in debugging cases) |
| 161 : | # and it should return a boolean, not a string. &if is called in a nonstandard way | ||
| 162 : | # by &template, with $args as an arrayref instead of a hashref. this is a hack! yay! | ||
| 163 : | |||
| 164 : | # OK, this is a pluggin architecture. it iterates through attributes of the "if" tag, | ||
| 165 : | # and for each predicate $p, it calls &if_$p in an object-oriented way, continuing the | ||
| 166 : | # grand templating theme of an object-oriented pluggable architecture using ->can($). | ||
| 167 : | sub if { | ||
| 168 : | my ($self, $args) = @_[0,-1]; | ||
| 169 : | # A single if "or"s it's components. Nesting produces "and". | ||
| 170 : | |||
| 171 : | my @args = @$args; # Hahahahaha, get it?! | ||
| 172 : | |||
| 173 : | if (@args % 2 != 0) { | ||
| 174 : | # flip out and kill people, but do not commit seppuku | ||
| 175 : | print '<!--&if recieved an uneven number of arguments. This shouldn\'t happen, but I\'ll let it slide.-->\n'; | ||
| 176 : | } | ||
| 177 : | |||
| 178 : | while (@args > 1) { | ||
| 179 : | my ($key, $value) = (shift @args, shift @args); | ||
| 180 : | |||
| 181 : | # a non-existent &if_$key is the same as a false result, but we're ORing, so it's OK | ||
| 182 : | my $sub = "if_$key"; # perl doesn't like it when you try to construct a string right in a method invocation | ||
| 183 : | if ($self->can("if_$key") and $self->$sub("$value")) { | ||
| 184 : | return 1; | ||
| 185 : | } | ||
| 186 : | } | ||
| 187 : | |||
| 188 : | return 0; | ||
| 189 : | } | ||
| 190 : | |||
| 191 : | sh002i | 469 | ################################################################################ |
| 192 : | # Macros used by content generators to render common idioms | ||
| 193 : | ################################################################################ | ||
| 194 : | |||
| 195 : | # pathMacro(HASHREF, LIST) - helper macro for <!--#path--> escape: the hash | ||
| 196 : | # reference contains the "style", "image", and "text" arguments to the escape. | ||
| 197 : | # The LIST consists of ordered key-value pairs of the form: | ||
| 198 : | # | ||
| 199 : | # "Page Name" => URL | ||
| 200 : | # | ||
| 201 : | # If the page should not have a link associated with it, the URL should be left | ||
| 202 : | # empty. Authentication data is added to the URL so you don't have to. A fully- | ||
| 203 : | # formed path line is returned, suitable for returning by a function | ||
| 204 : | # implementing the #path escape. | ||
| 205 : | # | ||
| 206 : | sub pathMacro { | ||
| 207 : | malsyned | 323 | my $self = shift; |
| 208 : | sh002i | 469 | my %args = %{ shift() }; |
| 209 : | my @path = @_; | ||
| 210 : | my $sep; | ||
| 211 : | if ($args{style} eq "image") { | ||
| 212 : | $sep = CGI::img({-src=>$args{image}, -alt=>$args{text}}); | ||
| 213 : | } else { | ||
| 214 : | $sep = $args{text}; | ||
| 215 : | } | ||
| 216 : | my $auth = $self->url_authen_args; | ||
| 217 : | my @result; | ||
| 218 : | while (@path) { | ||
| 219 : | my $name = shift @path; | ||
| 220 : | my $url = shift @path; | ||
| 221 : | push @result, $url | ||
| 222 : | ? CGI::a({-href=>"$url?$auth"}, $name) | ||
| 223 : | : $name; | ||
| 224 : | } | ||
| 225 : | return join($sep, @result), "\n"; | ||
| 226 : | } | ||
| 227 : | |||
| 228 : | sub siblingsMacro { | ||
| 229 : | my $self = shift; | ||
| 230 : | my @siblings = @_; | ||
| 231 : | my $sep = CGI::br(); | ||
| 232 : | my $auth = $self->url_authen_args; | ||
| 233 : | my @result; | ||
| 234 : | while (@siblings) { | ||
| 235 : | my $name = shift @siblings; | ||
| 236 : | my $url = shift @siblings; | ||
| 237 : | push @result, $url | ||
| 238 : | ? CGI::a({-href=>"$url?$auth"}, $name) | ||
| 239 : | : $name; | ||
| 240 : | } | ||
| 241 : | return join($sep, @result), "\n"; | ||
| 242 : | } | ||
| 243 : | |||
| 244 : | sub navMacro { | ||
| 245 : | my $self = shift; | ||
| 246 : | my %args = %{ shift() }; | ||
| 247 : | my @links = @_; | ||
| 248 : | my $auth = $self->url_authen_args; | ||
| 249 : | my @result; | ||
| 250 : | while (@links) { | ||
| 251 : | my $name = shift @links; | ||
| 252 : | my $url = shift @links; | ||
| 253 : | push @result, $url | ||
| 254 : | ? CGI::a({-href=>"$url?$auth"}, $name) | ||
| 255 : | : $name; | ||
| 256 : | } | ||
| 257 : | return join($args{separator}, @result), "\n"; | ||
| 258 : | } | ||
| 259 : | |||
| 260 : | # hidden_fields(LIST) - return hidden <INPUT> tags for each field mentioned in | ||
| 261 : | # LIST (or all fields if list is empty), taking data from the current request. | ||
| 262 : | # | ||
| 263 : | sub hidden_fields($;@) { | ||
| 264 : | my $self = shift; | ||
| 265 : | malsyned | 323 | my $r = $self->{r}; |
| 266 : | sh002i | 469 | my @fields = @_; |
| 267 : | @fields or @fields = $r->param; | ||
| 268 : | malsyned | 323 | my $courseEnvironment = $self->{courseEnvironment}; |
| 269 : | my $html = ""; | ||
| 270 : | |||
| 271 : | sh002i | 469 | foreach my $param (@fields) { |
| 272 : | malsyned | 323 | my $value = $r->param($param); |
| 273 : | malsyned | 447 | $html .= CGI::input({-type=>"hidden",-name=>"$param",-value=>"$value"}); |
| 274 : | malsyned | 323 | } |
| 275 : | return $html; | ||
| 276 : | } | ||
| 277 : | |||
| 278 : | sh002i | 469 | # hidden_authen_fields() - use hidden_fields to return hidden <INPUT> tags for |
| 279 : | # request fields used in authentication. | ||
| 280 : | # | ||
| 281 : | sub hidden_authen_fields($) { | ||
| 282 : | my $self = shift; | ||
| 283 : | return $self->hidden_fields("user","effectiveUser","key"); | ||
| 284 : | } | ||
| 285 : | sh002i | 425 | |
| 286 : | sh002i | 469 | # url_args(LIST) - return a URL query string (without the leading `?') |
| 287 : | # containing values for each field mentioned in LIST, or all fields if list is | ||
| 288 : | # empty. Data is taken from the current request. | ||
| 289 : | # | ||
| 290 : | sub url_args($;@) { | ||
| 291 : | sh002i | 425 | my $self = shift; |
| 292 : | my $r = $self->{r}; | ||
| 293 : | my @fields = @_; | ||
| 294 : | @fields or @fields = $r->param; | ||
| 295 : | my $courseEnvironment = $self->{courseEnvironment}; | ||
| 296 : | |||
| 297 : | sh002i | 469 | my @pairs; |
| 298 : | malsyned | 441 | foreach my $param (@fields) { |
| 299 : | sh002i | 469 | my $value = $r->param($param) || ""; |
| 300 : | push @pairs, uri_escape($param) . "=" . uri_escape($value); | ||
| 301 : | sh002i | 425 | } |
| 302 : | sh002i | 469 | |
| 303 : | return join("&", @pairs); | ||
| 304 : | sh002i | 425 | } |
| 305 : | |||
| 306 : | sh002i | 469 | # url_authen_args() - use url_args to return a URL query string for request |
| 307 : | # fields used in authentication. | ||
| 308 : | # | ||
| 309 : | sub url_authen_args($) { | ||
| 310 : | my $self = shift; | ||
| 311 : | my $r = $self->{r}; | ||
| 312 : | return $self->url_args("user","effectiveUser","key"); | ||
| 313 : | malsyned | 390 | } |
| 314 : | |||
| 315 : | sh002i | 469 | # print_form_data(BEGIN, MIDDLE, END, OMIT) - return a string containing request |
| 316 : | # fields not matched by OMIT, placing BEGIN before each field name, MIDDLE | ||
| 317 : | # between each field and its value, and END after each value. Values are taken | ||
| 318 : | # from the current request. OMIT is a quoted reguar expression. | ||
| 319 : | # | ||
| 320 : | sub print_form_data { | ||
| 321 : | my ($self, $begin, $middle, $end, $qr_omit) = @_; | ||
| 322 : | my $return_string = ""; | ||
| 323 : | my $r=$self->{r}; | ||
| 324 : | my @form_data = $r->param; | ||
| 325 : | foreach my $name (@form_data) { | ||
| 326 : | next if ($qr_omit and $name =~ /$qr_omit/); | ||
| 327 : | my @values = $r->param($name); | ||
| 328 : | foreach my $variable (qw(begin name middle value end)) { | ||
| 329 : | no strict 'refs'; | ||
| 330 : | ${$variable} = "" unless defined ${$variable}; | ||
| 331 : | } | ||
| 332 : | foreach my $value (@values) { | ||
| 333 : | $return_string .= "$begin$name$middle$value$end"; | ||
| 334 : | } | ||
| 335 : | } | ||
| 336 : | return $return_string; | ||
| 337 : | malsyned | 390 | } |
| 338 : | |||
| 339 : | sh002i | 469 | ################################################################################ |
| 340 : | # Generic versions of template escapes | ||
| 341 : | ################################################################################ | ||
| 342 : | malsyned | 390 | |
| 343 : | sh002i | 469 | # Reminder: here are the template functions currently defined: |
| 344 : | # | ||
| 345 : | sh002i | 555 | # head |
| 346 : | sh002i | 469 | # path |
| 347 : | # style = text|image | ||
| 348 : | # image = URL of image | ||
| 349 : | # text = text separator | ||
| 350 : | sh002i | 505 | # links |
| 351 : | sh002i | 469 | # siblings |
| 352 : | # nav | ||
| 353 : | # style = text|image | ||
| 354 : | # imageprefix = prefix to image URL | ||
| 355 : | # imagesuffix = suffix to image URL | ||
| 356 : | # separator = HTML to place in between links | ||
| 357 : | # title | ||
| 358 : | # body | ||
| 359 : | malsyned | 313 | |
| 360 : | malsyned | 349 | sub header { |
| 361 : | malsyned | 305 | my $self = shift; |
| 362 : | sh002i | 469 | my $r = $self->{r}; |
| 363 : | malsyned | 349 | $r->content_type('text/html'); |
| 364 : | $r->send_http_header(); | ||
| 365 : | } | ||
| 366 : | |||
| 367 : | sh002i | 526 | # drunk code. rewrite. |
| 368 : | sh002i | 505 | sub links { |
| 369 : | malsyned | 353 | my $self = shift; |
| 370 : | sh002i | 469 | my $ce = $self->{courseEnvironment}; |
| 371 : | sh002i | 526 | my $userName = $self->{r}->param("user"); |
| 372 : | my $courseName = $ce->{courseName}; | ||
| 373 : | sh002i | 469 | my $root = $ce->{webworkURLs}->{root}; |
| 374 : | sh002i | 526 | my $permLevel = WeBWorK::DB::Auth->new($ce)->getPermissions($userName); |
| 375 : | sh002i | 562 | return "" unless defined $permLevel; |
| 376 : | sh002i | 526 | |
| 377 : | sh002i | 469 | my $probSets = "$root/$courseName/?" . $self->url_authen_args(); |
| 378 : | sh002i | 526 | my $prefs = "$root/$courseName/prefs/?" . $self->url_authen_args(); |
| 379 : | my $prof = "$root/$courseName/prof/?" . $self->url_authen_args(); | ||
| 380 : | my $profLine; | ||
| 381 : | if ($permLevel > 0) { | ||
| 382 : | $profLine = CGI::a({-href=>$prof}, "Professor") . CGI::br(), | ||
| 383 : | } | ||
| 384 : | my $help = $ce->{webworkURLs}->{docs} . "?" . $self->url_authen_args(); | ||
| 385 : | my $logout = "$root/$courseName/?user=$userName"; | ||
| 386 : | |||
| 387 : | sh002i | 476 | return |
| 388 : | sh002i | 469 | CGI::a({-href=>$probSets}, "Problem Sets"), CGI::br(), |
| 389 : | sh002i | 526 | CGI::a({-href=>$prefs}, "User Options"), CGI::br(), |
| 390 : | $profLine, | ||
| 391 : | CGI::a({-href=>$help}, "Help"), CGI::br(), | ||
| 392 : | sh002i | 476 | CGI::a({-href=>$logout}, "Log Out"), CGI::br(), |
| 393 : | ; | ||
| 394 : | malsyned | 353 | } |
| 395 : | |||
| 396 : | malsyned | 525 | # &if_can will return 1 if the current object->can("do $_[1]") |
| 397 : | sub if_can ($$) { | ||
| 398 : | my ($self, $arg) = (@_); | ||
| 399 : | |||
| 400 : | if ($self->can("$arg")) { | ||
| 401 : | return 1; | ||
| 402 : | } else { | ||
| 403 : | return 0; | ||
| 404 : | } | ||
| 405 : | } | ||
| 406 : | |||
| 407 : | malsyned | 313 | 1; |
| 408 : | malsyned | 508 | |
| 409 : | __END__ | ||
| 410 : | |||
| 411 : | =head1 AUTHOR | ||
| 412 : | |||
| 413 : | Written by Dennis Lambe Jr., malsyned (at) math.rochester.edu | ||
| 414 : | and Sam Hathaway, sh002i (at) math.rochester.edu. | ||
| 415 : | |||
| 416 : | =cut |
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