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 Reports the details of an error, current state and parameters
111 =head1 TEMPLATE TOOLKIT INTRODUCTION
113 The Template Toolkit uses it's own mini language described in
114 L<Template::Manual::Directives>.
116 A simple example would be :
122 Dear [% title %] [% surname %],
123 Thank you for your letter dated [% your.date %]. This is to
124 confirm that we have received it and will respond with a more
125 detailed response as soon as possible. In the mean time, we
126 enclose more details of ...
130 TT uses '[%' and '%]' (by default) to delimit directives within a template, and
131 the simple directives above just display the value of variable named within
132 those delimiters -- [% title %] will be replaced inline with the value of the
133 'title' variable passed in the 'stash' to the template when it is processed.
135 You can access nested data through the dot ('.') operator, which will
136 dereference array or hash elements, but can also be used to call methods on
137 objects, i.e. '[% name.salutation("Dear %s,") %]'. The other main operator is
138 underscore ('_'), which will concatonate strings or variables.
140 The value returned by a directive replaces the directive inline when the
141 template is processes, you can also SET a value which will not return anything,
142 or CALL a method or operation which will also not return anything.
144 You can specify expressions using the logical (and, or, not, ?:) and mathematic
145 operators (+ - * / % mod div).
147 Results of TT commands are interpolated in the place of the template tags, unless
148 using SET or CALL, i.e. [% SET foo = 1 %], [% GET foo.bar('quz'); %]
152 [% template.title or default.title %]
156 [% order.nitems ? checkout(order.total) : 'no items' %]
160 TT allows you to include or re-use templates through it's INCLUDE, PROCESS and
161 INSERT directives, which are fairly self explainatory. You can also re-use parts
162 of template with the BLOCK or MACRO directives.
164 Conditional and Looping constructs are simple and powerful, and TT provides an
165 inbuilt iterator and helper functions and classes that make life sweet.
167 Conditional directives are IF, UNLESS, ELSIF, ELSE and behave as they would in
173 Hello [% name %], does your mother know you're using her AOL account?
175 Sorry, you're not old enough to enter (and too dumb to lie about your age)
180 [% UNLESS text_mode %] [% INCLUDE biglogo %] [% END %]
184 Looping directives are FOREACH, LAST and BREAK.
186 FOREACH loops through a HASH or ARRAY processing the enclosed block for each
189 Looping through an array
191 [% FOREACH i = items %]
195 Looping through a hash
197 [% FOREACH u IN users %]
198 * [% u.key %] : [% u.value %]
201 Looping through an array of hashes
203 [% FOREACH user IN userlist %]
204 * [% user.id %] [% user.name %]
207 The LAST and BREAK directive can be used to exit the loop.
209 The FOREACH directive is implemented using the Template::Iterator module. A
210 reference to the iterator object for a FOREACH directive is implicitly available
211 in the 'loop' variable. The loop iterator object provides a selection of methods
212 including size(), max(), first(), last(), count(), etc
216 [% FOREACH item IN [ 'foo', 'bar', 'baz' ] -%]
217 [%- "<ul>\n" IF loop.first %]
218 <li>[% loop.count %]/[% loop.size %]: [% item %]
219 [%- "</ul>\n" IF loop.last %]
224 See Template::Iterator for further details on looping and the Iterator.
226 You might notice the minus ('-') operator in the example above, it is used to
227 remove a newline before or after a directive so that you can layout the Template
228 logic as above but the resulting output will look exactly how you require it.
230 You will also frequently see comments and multi-line directives, # at the start
231 of a directive marks it as a comment, i.e. '[%# this is a comment %]'. A
232 multiline directive looks like :
238 You can see that lines are terminated with a semi-colon (';') unless the
239 delimter ('%]') closes the directive.
241 For full details of the Template Toolkit see Template::Manual and
242 Template::Manual::Directives, you can also check the website, mailing list or
243 the Template Toolkit book published by O Reilly.
245 =head1 TEMPLATE PLUGINS, FILTERS AND MACROS
247 The Template Toolkit has a popular and powerful selection of Plugins and
250 TT Plugins provide additional functionality within Templates, from accessing CGI
251 and databases directly, handling paging or simple integration with Class::DBI
252 (for those rare occasions where you don't actually need Maypole). See
253 L<Template::Manual::Plugins>.
255 One plugin that is indispensible when using Maypole and the Template View is
256 C<Template::Plugin::Class> -- This allows you to import and use any class
257 installed within a template. For example :
261 [% USE foo = Class('Foo') %]
266 Would do the equivilent of 'use Foo; Foo->bar;' in perl. See
267 L<Template::Plugin::Class> for details.
269 TT Filters process strings or blocks within a template, allowing you to
270 truncate, format, escape or encode trivially. A useful selection is included
271 with Template Toolkit and they can also be found on CPAN or can be written
272 easily. See L<Template::Manual::Filters>.
274 TT Macros allow you to reuse small blocks of content, directives, etc. The MACRO
275 directive allows you to define a directive or directive block which is then
276 evaluated each time the macro is called. Macros can be passed named parameters
279 Once a MACRO is defined within a template or 'include'd template it can be used
280 as if it were a native TT directive. Maypole provides a selection of powerful
281 and useful macros in the templates/ directory of the package and these are used
282 in the beerdb and default templates. See the MACRO section of the
283 L<Template::Manual::Directives> documentation.
285 =head1 ACCESSING MAYPOLE VALUES
289 You can access the request in your templates in order to see the action, table, etc as well
290 as parameters passed through forms :
294 Hello [% request.params.forename %] [% request.params.surname %] !
298 Are you want to [% request.action %] in the [% request.table %] ?
302 You can access your maypole application configuration through the config variable :
304 <link base="[% config.uri_base %]"/>
306 =head2 object and objects
308 Objects are passed to the request using r->objects($arrayref) and are accessed in the templates
309 as an array called objects.
311 [% FOR objects %] <a href="[% config.uri_base %]/[% request.table %]/view/[% object.id %]"> [% object %] </a> [% END %]
313 =head1 MAYPOLE MACROS AND FILTERS
315 Maypole provides a collection of useful and powerful macros in the templates/factory/macros
316 and other templates. These can be used in any template with [% PROCESS templatename %].
320 This creates an <A HREF="..."> to a command in the Apache::MVC system by
321 catenating the base URL, table, command, and any arguments.
323 =head2 maybe_link_view
325 C<maybe_link_view> takes something returned from the database - either
326 some ordinary data, or an object in a related class expanded by a
327 has-a relationship. If it is an object, it constructs a link to the view
328 command for that object. Otherwise, it just displays the data.
332 This is an include template rather than a macro, and it controls the pager
333 display at the bottom (by default) of the factory list and search views/template.
334 It expects a C<pager> template argument which responds to the L<Data::Page> interface.
336 This macro is in the pager template and used as :
340 Maypole provides a pager for list and search actions, otherwise you can
341 provide a pager in the template using Template::Plugin::Pagination.
343 [% USE pager = Pagination(objects, page.current, page.rows) %]
347 The pager will use a the request action as the action in the url unless the
348 pager_action variable is set, which it will use instead if available.
361 <html><head><title>Maypole error page</title>
362 <style type="text/css">
363 body { background-color:#7d95b5; font-family: sans-serif}
364 p { background-color: #fff; padding: 5px; }
365 pre { background-color: #fff; padding: 5px; border: 1px dotted black }
368 .lhs {background-color: #ffd; }
369 .rhs {background-color: #dff; }
372 <h1> Maypole application error </h1>
374 <p> This application living at <code>[%request.config.uri_base%]</code>,
375 [%request.config.application_name || "which is unnamed" %], has
376 produced an error. The adminstrator should be able to understand
377 this error message and fix the problem.</p>
379 <h2> Some basic facts </h2>
381 <p> The error was found in the [% err_type %] stage of processing
382 the path "[% request.path %]". The error text returned was:
388 <h2> Request details </h2>
391 [% FOR thing = ["model_class", "table", "template", "path",
392 "content_type", "document_encoding", "action", "args", "objects"] %]
393 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
394 request.$thing.list.join(" , ") %] </td></tr>
398 <h2> Application configuration </h2>
400 [% FOR thing = config.keys %]
401 <tr> <td class="lhs"> [%thing %] </td> <td class="rhs"> [%
402 config.$thing.list.join(" , ") %] </td></tr>