1 package Maypole::View::TT;
2 use base 'Maypole::View::Base';
3 use Maypole::Constants;
5 use File::Spec::Functions qw(catdir tmpdir);
8 { local $/; $error_template = <DATA>; }
14 my ( $self, $r ) = @_;
15 unless ($self->{tt}) {
16 my $view_options = $r->config->view_options || {};
17 $self->{provider} = Template::Provider->new($view_options);
18 $self->{tt} = Template->new({
20 LOAD_TEMPLATES => [ $self->{provider} ],
24 $self->{provider}->include_path([ $self->paths($r) ]);
26 my $template_file = $r->template;
28 my $ext = $r->config->template_extension;
29 $template_file .= $ext if defined $ext;
32 my $processed_ok = eval{$self->{tt}->process($template_file, { $self->vars($r) }, \$output );};
34 $r->{output} = $output;
38 warn "fatal error in template '$template_file' : $@\n";
39 $r->{error} = "fatal error in template '$template_file' : $@";
41 warn "TT error for template '$template_file'\n" . $self->{tt}->error;
42 $r->{error} = "TT error for template '$template_file'\n" . $self->{tt}->error;
50 my ($self, $r, $error, $type) = @_;
52 # Need to be very careful here.
53 my $tt = Template->new;
54 if ($tt->process(\$error_template,
55 { err_type => $type, error => $error,
56 config => { %{$r->{config}}},
57 request => $r, # We have that at least
58 eval{$self->vars($r)} }, \$output )) {
59 $r->{output} = $output;
60 if ($tt->error) { $r->{output} = "<html><body>Even the error template
61 errored - ".$tt->error."</body></html>"; }
62 $r->{content_type} ||= "text/html";
63 $r->{document_encoding} ||= "utf-8";
72 Maypole::View::TT - A Template Toolkit view class for Maypole
76 BeerDB->config->view("Maypole::View::TT"); # The default anyway
78 # Set some Template Toolkit options
79 BeerDB->config->view_options( {
81 COMPILE_DIR => '/var/tmp/mysite/templates',
96 This is the default view class for Maypole; it uses the Template Toolkit to fill
97 in templates with the objects produced by Maypole's model classes. Please see
98 the L<Maypole manual|Maypole::Manual>, and in particular, the
99 L<view|Maypole::Manual::View> chapter for the template variables available and
100 for a refresher on how template components are resolved.
102 The underlying Template toolkit object is configured through
103 C<$r-E<gt>config-E<gt>view_options>. See L<Template|Template> for available
110 Processes the template and sets the output. See L<Maypole::View::Base>
114 Reports the details of an error, current state and parameters
118 =head1 TEMPLATE TOOLKIT INTRODUCTION
120 The Template Toolkit uses it's own mini language described in
121 L<Template::Manual::Directives>.
123 A simple example would be :
129 Dear [% title %] [% surname %],
130 Thank you for your letter dated [% your.date %]. This is to
131 confirm that we have received it and will respond with a more
132 detailed response as soon as possible. In the mean time, we
133 enclose more details of ...
137 TT uses '[%' and '%]' (by default) to delimit directives within a template, and
138 the simple directives above just display the value of variable named within
139 those delimiters -- [% title %] will be replaced inline with the value of the
140 'title' variable passed in the 'stash' to the template when it is processed.
142 You can access nested data through the dot ('.') operator, which will
143 dereference array or hash elements, but can also be used to call methods on
144 objects, i.e. '[% name.salutation("Dear %s,") %]'. The other main operator is
145 underscore ('_'), which will concatonate strings or variables.
147 The value returned by a directive replaces the directive inline when the
148 template is processes, you can also SET a value which will not return anything,
149 or CALL a method or operation which will also not return anything.
151 You can specify expressions using the logical (and, or, not, ?:) and mathematic
152 operators (+ - * / % mod div).
154 Results of TT commands are interpolated in the place of the template tags, unless
155 using SET or CALL, i.e. [% SET foo = 1 %], [% GET foo.bar('quz'); %]
159 [% template.title or default.title %]
163 [% order.nitems ? checkout(order.total) : 'no items' %]
167 TT allows you to include or re-use templates through it's INCLUDE, PROCESS and
168 INSERT directives, which are fairly self explainatory. You can also re-use parts
169 of template with the BLOCK or MACRO directives.
171 Conditional and Looping constructs are simple and powerful, and TT provides an
172 inbuilt iterator and helper functions and classes that make life sweet.
174 Conditional directives are IF, UNLESS, ELSIF, ELSE and behave as they would in
180 Hello [% name %], does your mother know you're using her AOL account?
182 Sorry, you're not old enough to enter (and too dumb to lie about your age)
187 [% UNLESS text_mode %] [% INCLUDE biglogo %] [% END %]
191 Looping directives are FOREACH, LAST and BREAK.
193 FOREACH loops through a HASH or ARRAY processing the enclosed block for each
196 Looping through an array
198 [% FOREACH i = items %]
202 Looping through a hash
204 [% FOREACH u IN users %]
205 * [% u.key %] : [% u.value %]
208 Looping through an array of hashes
210 [% FOREACH user IN userlist %]
211 * [% user.id %] [% user.name %]
214 The LAST and BREAK directive can be used to exit the loop.
216 The FOREACH directive is implemented using the Template::Iterator module. A
217 reference to the iterator object for a FOREACH directive is implicitly available
218 in the 'loop' variable. The loop iterator object provides a selection of methods
219 including size(), max(), first(), last(), count(), etc
223 [% FOREACH item IN [ 'foo', 'bar', 'baz' ] -%]
224 [%- "<ul>\n" IF loop.first %]
225 <li>[% loop.count %]/[% loop.size %]: [% item %]
226 [%- "</ul>\n" IF loop.last %]
231 See Template::Iterator for further details on looping and the Iterator.
233 You might notice the minus ('-') operator in the example above, it is used to
234 remove a newline before or after a directive so that you can layout the Template
235 logic as above but the resulting output will look exactly how you require it.
237 You will also frequently see comments and multi-line directives, # at the start
238 of a directive marks it as a comment, i.e. '[%# this is a comment %]'. A
239 multiline directive looks like :
245 You can see that lines are terminated with a semi-colon (';') unless the
246 delimter ('%]') closes the directive.
248 For full details of the Template Toolkit see Template::Manual and
249 Template::Manual::Directives, you can also check the website, mailing list or
250 the Template Toolkit book published by O Reilly.
252 =head1 TEMPLATE PLUGINS, FILTERS AND MACROS
254 The Template Toolkit has a popular and powerful selection of Plugins and
257 TT Plugins provide additional functionality within Templates, from accessing CGI
258 and databases directly, handling paging or simple integration with Class::DBI
259 (for those rare occasions where you don't actually need Maypole). See
260 L<Template::Manual::Plugins>.
262 One plugin that is indispensible when using Maypole and the Template View is
263 C<Template::Plugin::Class> -- This allows you to import and use any class
264 installed within a template. For example :
268 [% USE foo = Class('Foo') %]
273 Would do the equivilent of 'use Foo; Foo->bar;' in perl. See
274 L<Template::Plugin::Class> for details.
276 TT Filters process strings or blocks within a template, allowing you to
277 truncate, format, escape or encode trivially. A useful selection is included
278 with Template Toolkit and they can also be found on CPAN or can be written
279 easily. See L<Template::Manual::Filters>.
281 TT Macros allow you to reuse small blocks of content, directives, etc. The MACRO
282 directive allows you to define a directive or directive block which is then
283 evaluated each time the macro is called. Macros can be passed named parameters
286 Once a MACRO is defined within a template or 'include'd template it can be used
287 as if it were a native TT directive. Maypole provides a selection of powerful
288 and useful macros in the templates/ directory of the package and these are used
289 in the beerdb and default templates. See the MACRO section of the
290 L<Template::Manual::Directives> documentation.
292 =head1 ACCESSING MAYPOLE VALUES
296 You can access the request in your templates in order to see the action, table, etc as well
297 as parameters passed through forms :
301 Hello [% request.params.forename %] [% request.params.surname %] !
305 Are you want to [% request.action %] in the [% request.table %] ?
309 You can access your maypole application configuration through the config variable :
311 <link base="[% config.uri_base %]"/>
313 =head2 object and objects
315 Objects are passed to the request using r->objects($arrayref) and are accessed in the templates
316 as an array called objects.
318 [% FOR objects %] <a href="[% config.uri_base %]/[% request.table %]/view/[% object.id %]"> [% object %] </a> [% END %]
320 =head1 MAYPOLE MACROS AND FILTERS
322 Maypole provides a collection of useful and powerful macros in the templates/factory/macros
323 and other templates. These can be used in any template with [% PROCESS templatename %].
327 This creates an <A HREF="..."> to a command in the Apache::MVC system by
328 catenating the base URL, table, command, and any arguments.
330 =head2 maybe_link_view
332 C<maybe_link_view> takes something returned from the database - either
333 some ordinary data, or an object in a related class expanded by a
334 has-a relationship. If it is an object, it constructs a link to the view
335 command for that object. Otherwise, it just displays the data.
339 This is an include template rather than a macro, and it controls the pager
340 display at the bottom (by default) of the factory list and search views/template.
341 It expects a C<pager> template argument which responds to the L<Data::Page> interface.
343 This macro is in the pager template and used as :
347 Maypole provides a pager for list and search actions, otherwise you can
348 provide a pager in the template using Template::Plugin::Pagination.
350 [% USE pager = Pagination(objects, page.current, page.rows) %]
354 The pager will use a the request action as the action in the url unless the
355 pager_action variable is set, which it will use instead if available.
368 <html><head><title>Maypole error page</title>
369 <style type="text/css">
370 body { background-color:#7d95b5; font-family: sans-serif}
371 p { background-color: #fff; padding: 5px; }
372 pre { background-color: #fff; padding: 5px; border: 1px dotted black }
375 .lhs {background-color: #ffd; }
376 .rhs {background-color: #dff; }
379 <h1> Maypole application error </h1>
381 <p> This application living at <code>[%request.config.uri_base%]</code>,
382 [%request.config.application_name || "which is unnamed" %], has
383 produced an error. The adminstrator should be able to understand
384 this error message and fix the problem.</p>
386 <h2> Some basic facts </h2>
388 <p> The error was found in the [% err_type %] stage of processing
389 the path "[% request.path %]". The error text returned was:
395 <h2> Request details </h2>
398 [% FOR thing = ["model_class", "table", "template", "path",
399 "content_type", "document_encoding", "action", "args", "objects"] %]
400 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
401 request.$thing.list.join(" , ") %] </td></tr>
405 <h2> Application configuration </h2>
407 [% FOR thing = config.keys %]
408 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
409 config.$thing.list.join(" , ") %] </td></tr>