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, $r ) = @_;
16 unless ($self->{tt}) {
17 my $view_options = $r->config->view_options || {};
18 $self->{provider} = Template::Provider->new($view_options);
19 $self->{tt} = Template->new({
21 LOAD_TEMPLATES => [ $self->{provider} ],
25 $self->{provider}->include_path([ $self->paths($r) ]);
27 my $template_file = $r->template;
28 my $ext = $r->config->template_extension;
29 $template_file .= $ext if defined $ext;
32 if ($self->{tt}->process($template_file, { $self->vars($r) }, \$output )) {
33 $r->{output} = $output;
36 $r->{error} = "TT error for template '$template_file'\n" . $self->{tt}->error;
43 my ($self, $r, $error, $type) = @_;
45 # Need to be very careful here.
46 my $tt = Template->new;
47 if ($tt->process(\$error_template,
48 { err_type => $type, error => $error,
49 config => { %{$r->{config}}},
50 request => $r, # We have that at least
51 eval{$self->vars($r)} }, \$output )) {
52 $r->{output} = $output;
53 if ($tt->error) { $r->{output} = "<html><body>Even the error template
54 errored - ".$tt->error."</body></html>"; }
55 $r->{content_type} ||= "text/html";
56 $r->{document_encoding} ||= "utf-8";
65 Maypole::View::TT - A Template Toolkit view class for Maypole
69 BeerDB->config->view("Maypole::View::TT"); # The default anyway
71 # Set some Template Toolkit options
72 BeerDB->config->view_options( {
74 COMPILE_DIR => '/var/tmp/mysite/templates',
89 This is the default view class for Maypole; it uses the Template Toolkit to fill
90 in templates with the objects produced by Maypole's model classes. Please see
91 the L<Maypole manual|Maypole::Manual>, and in particular, the
92 L<view|Maypole::Manual::View> chapter for the template variables available and
93 for a refresher on how template components are resolved.
95 The underlying Template toolkit object is configured through
96 C<$r-E<gt>config-E<gt>view_options>. See L<Template|Template> for available
103 Processes the template and sets the output. See L<Maypole::View::Base>
107 =head1 TEMPLATE TOOLKIT INTRODUCTION
109 The Template Toolkit uses it's own mini language described in
110 L<Template::Manual::Directives>.
112 A simple example would be :
118 Dear [% title %] [% surname %],
119 Thank you for your letter dated [% your.date %]. This is to
120 confirm that we have received it and will respond with a more
121 detailed response as soon as possible. In the mean time, we
122 enclose more details of ...
126 TT uses '[%' and '%]' (by default) to delimit directives within a template, and
127 the simple directives above just display the value of variable named within
128 those delimiters -- [% title %] will be replaced inline with the value of the
129 'title' variable passed in the 'stash' to the template when it is processed.
131 You can access nested data through the dot ('.') operator, which will
132 dereference array or hash elements, but can also be used to call methods on
133 objects, i.e. '[% name.salutation("Dear %s,") %]'. The other main operator is
134 underscore ('_'), which will concatonate strings or variables.
136 The value returned by a directive replaces the directive inline when the
137 template is processes, you can also SET a value which will not return anything,
138 or CALL a method or operation which will also not return anything.
140 You can specify expressions using the logical (and, or, not, ?:) and mathematic
141 operators (+ - * / % mod div).
143 Results of TT commands are interpolated in the place of the template tags, unless
144 using SET or CALL, i.e. [% SET foo = 1 %], [% GET foo.bar('quz'); %]
148 [% template.title or default.title %]
152 [% order.nitems ? checkout(order.total) : 'no items' %]
156 TT allows you to include or re-use templates through it's INCLUDE, PROCESS and
157 INSERT directives, which are fairly self explainatory. You can also re-use parts
158 of template with the BLOCK or MACRO directives.
160 Conditional and Looping constructs are simple and powerful, and TT provides an
161 inbuilt iterator and helper functions and classes that make life sweet.
163 Conditional directives are IF, UNLESS, ELSIF, ELSE and behave as they would in
169 Hello [% name %], does your mother know you're using her AOL account?
171 Sorry, you're not old enough to enter (and too dumb to lie about your age)
176 [% UNLESS text_mode %] [% INCLUDE biglogo %] [% END %]
180 Looping directives are FOREACH, LAST and BREAK.
182 FOREACH loops through a HASH or ARRAY processing the enclosed block for each
185 Looping through an array
187 [% FOREACH i = items %]
191 Looping through a hash
193 [% FOREACH u IN users %]
194 * [% u.key %] : [% u.value %]
197 Looping through an array of hashes
199 [% FOREACH user IN userlist %]
200 * [% user.id %] [% user.name %]
203 The LAST and BREAK directive can be used to exit the loop.
205 The FOREACH directive is implemented using the Template::Iterator module. A
206 reference to the iterator object for a FOREACH directive is implicitly available
207 in the 'loop' variable. The loop iterator object provides a selection of methods
208 including size(), max(), first(), last(), count(), etc
212 [% FOREACH item IN [ 'foo', 'bar', 'baz' ] -%]
213 [%- "<ul>\n" IF loop.first %]
214 <li>[% loop.count %]/[% loop.size %]: [% item %]
215 [%- "</ul>\n" IF loop.last %]
220 See Template::Iterator for further details on looping and the Iterator.
222 You might notice the minus ('-') operator in the example above, it is used to
223 remove a newline before or after a directive so that you can layout the Template
224 logic as above but the resulting output will look exactly how you require it.
226 You will also frequently see comments and multi-line directives, # at the start
227 of a directive marks it as a comment, i.e. '[%# this is a comment %]'. A
228 multiline directive looks like :
234 You can see that lines are terminated with a semi-colon (';') unless the
235 delimter ('%]') closes the directive.
237 For full details of the Template Toolkit see Template::Manual and
238 Template::Manual::Directives, you can also check the website, mailing list or
239 the Template Toolkit book published by O Reilly.
241 =head1 TEMPLATE PLUGINS, FILTERS AND MACROS
243 The Template Toolkit has a popular and powerful selection of Plugins and
246 TT Plugins provide additional functionality within Templates, from accessing CGI
247 and databases directly, handling paging or simple integration with Class::DBI
248 (for those rare occasions where you don't actually need Maypole). See
249 L<Template::Manual::Plugins>.
251 One plugin that is indispensible when using Maypole and the Template View is
252 C<Template::Plugin::Class> -- This allows you to import and use any class
253 installed within a template. For example :
257 [% USE foo = Class('Foo') %]
262 Would do the equivilent of 'use Foo; Foo->bar;' in perl. See
263 L<Template::Plugin::Class> for details.
265 TT Filters process strings or blocks within a template, allowing you to
266 truncate, format, escape or encode trivially. A useful selection is included
267 with Template Toolkit and they can also be found on CPAN or can be written
268 easily. See L<Template::Manual::Filters>.
270 TT Macros allow you to reuse small blocks of content, directives, etc. The MACRO
271 directive allows you to define a directive or directive block which is then
272 evaluated each time the macro is called. Macros can be passed named parameters
275 Once a MACRO is defined within a template or 'include'd template it can be used
276 as if it were a native TT directive. Maypole provides a selection of powerful
277 and useful macros in the templates/ directory of the package and these are used
278 in the beerdb and default templates. See the MACRO section of the
279 L<Template::Manual::Directives> documentation.
281 =head1 ACCESSING MAYPOLE VALUES
285 You can access the request in your templates in order to see the action, table, etc as well
286 as parameters passed through forms :
290 Hello [% request.params.forename %] [% request.params.surname %] !
294 Are you want to [% request.action %] in the [% request.table %] ?
298 You can access your maypole application configuration through the config variable :
300 <link base="[% config.uri_base %]"/>
302 =head2 object and objects
304 Objects are passed to the request using r->objects($arrayref) and are accessed in the templates
305 as an array called objects.
307 [% FOR objects %] <a href="[% config.uri_base %]/[% request.table %]/view/[% object.id %]"> [% object %] </a> [% END %]
309 =head1 MAYPOLE MACROS AND FILTERS
311 Maypole provides a collection of useful and powerful macros in the templates/factory/macros
312 and other templates. These can be used in any template with [% PROCESS templatename %].
316 This creates an <A HREF="..."> to a command in the Apache::MVC system by
317 catenating the base URL, table, command, and any arguments.
319 =head2 maybe_link_view
321 C<maybe_link_view> takes something returned from the database - either
322 some ordinary data, or an object in a related class expanded by a
323 has-a relationship. If it is an object, it constructs a link to the view
324 command for that object. Otherwise, it just displays the data.
328 This is an include template rather than a macro, and it controls the pager
329 display at the bottom (by default) of the factory list and search views/template.
330 It expects a C<pager> template argument which responds to the L<Data::Page> interface.
332 This macro is in the pager template and used as :
336 Maypole provides a pager for list and search actions, otherwise you can
337 provide a pager in the template using Template::Plugin::Pagination.
339 [% USE pager = Pagination(objects, page.current, page.rows) %]
343 The pager will use a the request action as the action in the url unless the
344 pager_action variable is set, which it will use instead if available.
357 <html><head><title>Maypole error page</title>
358 <style type="text/css">
359 body { background-color:#7d95b5; font-family: sans-serif}
360 p { background-color: #fff; padding: 5px; }
361 pre { background-color: #fff; padding: 5px; border: 1px dotted black }
364 .lhs {background-color: #ffd; }
365 .rhs {background-color: #dff; }
368 <h1> Maypole application error </h1>
370 <p> This application living at <code>[%request.config.uri_base%]</code>,
371 [%request.config.application_name || "which is unnamed" %], has
372 produced an error. The adminstrator should be able to understand
373 this error message and fix the problem.</p>
375 <h2> Some basic facts </h2>
377 <p> The error was found in the [% err_type %] stage of processing
378 the path "[% request.path %]". The error text returned was:
384 <h2> Request details </h2>
387 [% FOR thing = ["model_class", "table", "template", "path",
388 "content_type", "document_encoding", "action", "args", "objects"] %]
389 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
390 request.$thing.list.join(" , ") %] </td></tr>
394 <h2> Application configuration </h2>
396 [% FOR thing = config.keys %]
397 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
398 config.$thing.list.join(" , ") %] </td></tr>