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;
37 $r->{error} = "TT error for template '$template_file'\n" . $self->{tt}->error;
44 my ($self, $r, $error, $type) = @_;
46 # Need to be very careful here.
47 my $tt = Template->new;
48 if ($tt->process(\$error_template,
49 { err_type => $type, error => $error,
50 config => { %{$r->{config}}},
51 request => $r, # We have that at least
52 eval{$self->vars($r)} }, \$output )) {
53 $r->{output} = $output;
54 if ($tt->error) { $r->{output} = "<html><body>Even the error template
55 errored - ".$tt->error."</body></html>"; }
56 $r->{content_type} ||= "text/html";
57 $r->{document_encoding} ||= "utf-8";
66 Maypole::View::TT - A Template Toolkit view class for Maypole
70 BeerDB->config->view("Maypole::View::TT"); # The default anyway
72 # Set some Template Toolkit options
73 BeerDB->config->view_options( {
75 COMPILE_DIR => '/var/tmp/mysite/templates',
90 This is the default view class for Maypole; it uses the Template Toolkit to fill
91 in templates with the objects produced by Maypole's model classes. Please see
92 the L<Maypole manual|Maypole::Manual>, and in particular, the
93 L<view|Maypole::Manual::View> chapter for the template variables available and
94 for a refresher on how template components are resolved.
96 The underlying Template toolkit object is configured through
97 C<$r-E<gt>config-E<gt>view_options>. See L<Template|Template> for available
104 Processes the template and sets the output. See L<Maypole::View::Base>
108 =head1 TEMPLATE TOOLKIT INTRODUCTION
110 The Template Toolkit uses it's own mini language described in
111 L<Template::Manual::Directives>.
113 A simple example would be :
119 Dear [% title %] [% surname %],
120 Thank you for your letter dated [% your.date %]. This is to
121 confirm that we have received it and will respond with a more
122 detailed response as soon as possible. In the mean time, we
123 enclose more details of ...
127 TT uses '[%' and '%]' (by default) to delimit directives within a template, and
128 the simple directives above just display the value of variable named within
129 those delimiters -- [% title %] will be replaced inline with the value of the
130 'title' variable passed in the 'stash' to the template when it is processed.
132 You can access nested data through the dot ('.') operator, which will
133 dereference array or hash elements, but can also be used to call methods on
134 objects, i.e. '[% name.salutation("Dear %s,") %]'. The other main operator is
135 underscore ('_'), which will concatonate strings or variables.
137 The value returned by a directive replaces the directive inline when the
138 template is processes, you can also SET a value which will not return anything,
139 or CALL a method or operation which will also not return anything.
141 You can specify expressions using the logical (and, or, not, ?:) and mathematic
142 operators (+ - * / % mod div).
144 Results of TT commands are interpolated in the place of the template tags, unless
145 using SET or CALL, i.e. [% SET foo = 1 %], [% GET foo.bar('quz'); %]
149 [% template.title or default.title %]
153 [% order.nitems ? checkout(order.total) : 'no items' %]
157 TT allows you to include or re-use templates through it's INCLUDE, PROCESS and
158 INSERT directives, which are fairly self explainatory. You can also re-use parts
159 of template with the BLOCK or MACRO directives.
161 Conditional and Looping constructs are simple and powerful, and TT provides an
162 inbuilt iterator and helper functions and classes that make life sweet.
164 Conditional directives are IF, UNLESS, ELSIF, ELSE and behave as they would in
170 Hello [% name %], does your mother know you're using her AOL account?
172 Sorry, you're not old enough to enter (and too dumb to lie about your age)
177 [% UNLESS text_mode %] [% INCLUDE biglogo %] [% END %]
181 Looping directives are FOREACH, LAST and BREAK.
183 FOREACH loops through a HASH or ARRAY processing the enclosed block for each
186 Looping through an array
188 [% FOREACH i = items %]
192 Looping through a hash
194 [% FOREACH u IN users %]
195 * [% u.key %] : [% u.value %]
198 Looping through an array of hashes
200 [% FOREACH user IN userlist %]
201 * [% user.id %] [% user.name %]
204 The LAST and BREAK directive can be used to exit the loop.
206 The FOREACH directive is implemented using the Template::Iterator module. A
207 reference to the iterator object for a FOREACH directive is implicitly available
208 in the 'loop' variable. The loop iterator object provides a selection of methods
209 including size(), max(), first(), last(), count(), etc
213 [% FOREACH item IN [ 'foo', 'bar', 'baz' ] -%]
214 [%- "<ul>\n" IF loop.first %]
215 <li>[% loop.count %]/[% loop.size %]: [% item %]
216 [%- "</ul>\n" IF loop.last %]
221 See Template::Iterator for further details on looping and the Iterator.
223 You might notice the minus ('-') operator in the example above, it is used to
224 remove a newline before or after a directive so that you can layout the Template
225 logic as above but the resulting output will look exactly how you require it.
227 You will also frequently see comments and multi-line directives, # at the start
228 of a directive marks it as a comment, i.e. '[%# this is a comment %]'. A
229 multiline directive looks like :
235 You can see that lines are terminated with a semi-colon (';') unless the
236 delimter ('%]') closes the directive.
238 For full details of the Template Toolkit see Template::Manual and
239 Template::Manual::Directives, you can also check the website, mailing list or
240 the Template Toolkit book published by O Reilly.
242 =head1 TEMPLATE PLUGINS, FILTERS AND MACROS
244 The Template Toolkit has a popular and powerful selection of Plugins and
247 TT Plugins provide additional functionality within Templates, from accessing CGI
248 and databases directly, handling paging or simple integration with Class::DBI
249 (for those rare occasions where you don't actually need Maypole). See
250 L<Template::Manual::Plugins>.
252 One plugin that is indispensible when using Maypole and the Template View is
253 C<Template::Plugin::Class> -- This allows you to import and use any class
254 installed within a template. For example :
258 [% USE foo = Class('Foo') %]
263 Would do the equivilent of 'use Foo; Foo->bar;' in perl. See
264 L<Template::Plugin::Class> for details.
266 TT Filters process strings or blocks within a template, allowing you to
267 truncate, format, escape or encode trivially. A useful selection is included
268 with Template Toolkit and they can also be found on CPAN or can be written
269 easily. See L<Template::Manual::Filters>.
271 TT Macros allow you to reuse small blocks of content, directives, etc. The MACRO
272 directive allows you to define a directive or directive block which is then
273 evaluated each time the macro is called. Macros can be passed named parameters
276 Once a MACRO is defined within a template or 'include'd template it can be used
277 as if it were a native TT directive. Maypole provides a selection of powerful
278 and useful macros in the templates/ directory of the package and these are used
279 in the beerdb and default templates. See the MACRO section of the
280 L<Template::Manual::Directives> documentation.
282 =head1 ACCESSING MAYPOLE VALUES
286 You can access the request in your templates in order to see the action, table, etc as well
287 as parameters passed through forms :
291 Hello [% request.params.forename %] [% request.params.surname %] !
295 Are you want to [% request.action %] in the [% request.table %] ?
299 You can access your maypole application configuration through the config variable :
301 <link base="[% config.uri_base %]"/>
303 =head2 object and objects
305 Objects are passed to the request using r->objects($arrayref) and are accessed in the templates
306 as an array called objects.
308 [% FOR objects %] <a href="[% config.uri_base %]/[% request.table %]/view/[% object.id %]"> [% object %] </a> [% END %]
310 =head1 MAYPOLE MACROS AND FILTERS
312 Maypole provides a collection of useful and powerful macros in the templates/factory/macros
313 and other templates. These can be used in any template with [% PROCESS templatename %].
317 This creates an <A HREF="..."> to a command in the Apache::MVC system by
318 catenating the base URL, table, command, and any arguments.
320 =head2 maybe_link_view
322 C<maybe_link_view> takes something returned from the database - either
323 some ordinary data, or an object in a related class expanded by a
324 has-a relationship. If it is an object, it constructs a link to the view
325 command for that object. Otherwise, it just displays the data.
329 This is an include template rather than a macro, and it controls the pager
330 display at the bottom (by default) of the factory list and search views/template.
331 It expects a C<pager> template argument which responds to the L<Data::Page> interface.
333 This macro is in the pager template and used as :
337 Maypole provides a pager for list and search actions, otherwise you can
338 provide a pager in the template using Template::Plugin::Pagination.
340 [% USE pager = Pagination(objects, page.current, page.rows) %]
344 The pager will use a the request action as the action in the url unless the
345 pager_action variable is set, which it will use instead if available.
358 <html><head><title>Maypole error page</title>
359 <style type="text/css">
360 body { background-color:#7d95b5; font-family: sans-serif}
361 p { background-color: #fff; padding: 5px; }
362 pre { background-color: #fff; padding: 5px; border: 1px dotted black }
365 .lhs {background-color: #ffd; }
366 .rhs {background-color: #dff; }
369 <h1> Maypole application error </h1>
371 <p> This application living at <code>[%request.config.uri_base%]</code>,
372 [%request.config.application_name || "which is unnamed" %], has
373 produced an error. The adminstrator should be able to understand
374 this error message and fix the problem.</p>
376 <h2> Some basic facts </h2>
378 <p> The error was found in the [% err_type %] stage of processing
379 the path "[% request.path %]". The error text returned was:
385 <h2> Request details </h2>
388 [% FOR thing = ["model_class", "table", "template", "path",
389 "content_type", "document_encoding", "action", "args", "objects"] %]
390 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
391 request.$thing.list.join(" , ") %] </td></tr>
395 <h2> Application configuration </h2>
397 [% FOR thing = config.keys %]
398 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
399 config.$thing.list.join(" , ") %] </td></tr>