NAME
Apache2::Controller::Render::Template - A2C render() with Template Toolkit
SYNOPSIS
# apache2 config file
PerlModule Apache2::Controller::Directives
# location of templates - must be defined
A2CRenderTemplateDir /var/myapp/templates
# looks for templates in /var/myapp/templates/foo/
<Location /foo>
SetHandler modperl
PerlInitHandler MyApp::Dispatch::Foo
</Location>
# see L<Apache2::Controller::Dispatch> for A2C Dispatch inheritance.
package MyApp::C::Foo; # let's assume this controller was dispatched
use strict;
use warnings;
use base qw(
Apache2::Controller
Apache2::Controller::Render::Template
MyApp::Model::Methods
MyApp::Security
);
use Apache2::Const -complie => qw( OK );
my @ALLOWED_METHODS = qw( default );
# suppose MyApp::Model::Methods connects dbh in startup sequence
# and suppose MyApp::Security implements my_detaint_path_args()
# to call a branch function for 'name' that detaints [ last, first ]
sub default {
my ($self) = @_;
my @path_args = $self->my_detaint_path_args('name'); # from $self->{path_args}
$self->{stash}{creditcards} = $self->{dbh}->fetchall_arrayref(
q{ SELECT ccnum, exp, addr1, zip, cac
FROM customer_credit_cards
WHERE lname = ? AND fname = ?
}, undef, @path_args
);
# request was like http://myserver.xyz/foo/Larry/Wall
$self->render(); # renders /var/myapp/templates/foo/default.html
return Apache2::Const::OK;
}
__END__
[%# /var/myapp/templates/foo/default.html %]
<p>Here is the credit card info you requested for
everyone named [% path_args.reverse.join(' ') %]:</p>
<ul>
[% FOREACH card = creditcards %]
[% FOREACH field = ['ccnum','exp','addr1','zip','cac'] %]
<li><strong>[% field %]:</strong> [% card.$field %]</li>
[% END %]
[% END %]
</ul>
[%# end template toolkit file %]DESCRIPTION
This module provides a nice rendering mechanism for Apache2::Controller.
STASH FUNCTIONS
Several subroutine references are automatically included in the stash for ease of use.
escape_html
Escape '<' and '>' characters using HTML::Entities.
uri_escape
See URI::Escape.
Dump
See YAML::Syck.
METHODS
render
render() accumulates template output into a variable before printing, so it may use a lot of memory if you expect a large data set.
It does this so it can intercept Template errors and kick up an exception to be printed using your error templates. See error().
render_fast
So if you are planning to get a large data set, you probably want to use $self->render_fast() and put the database query handle somewhere in $self->{stash} and call fetchrow() in a Template block.
With render_fast(), Template->process() outputs directly to Apache2::Request->print(). So if a Template error is encountered, some output may have already been sent to the browser, resulting in a completely screwed up screen when the exception is kicked back up to the server.
Tip: if you plan to use render_fast(), write a test suite that tests the output of your page.
Of course you could bypass rendering altogether and just use $self->print(). (Remember that $self is subclassed Apache2::Request.) Or maybe you should implement an ajax style control in the template and put a limit frame on the query above, or use a paging lib, etc. ...
error
If your template directory contains a subdirectory named 'error', then when the controller throws an exception, the exception object will be passed to a selected error template as 'X' in the stash. It also sets status (number) and status_line (from HTTP::Status::status_message() or from the values set in the Apache2::Controller::X exception).
If you have a template $template_dir/error/$status.html, where $status is the numeric http status code, then it will use that template.
For example:
203 HTTP_NON_AUTHORITATIVE => error/203.html
400 HTTP_BAD_REQUEST => error/400.html
404 NOT_FOUND => error/404.html
500 HTTP_INTERNAL_SERVER_ERROR => error/500.htmlFor example, $template_dir/error/400.html or $template_dir/error/403.html.
Otherwise it will look for $template_dir/error/default.html and try to use that, otherwise it will give up.
error() remembers across requests whether you do or don't have error templates for certain messages in the appropriate template directory, so it will be faster the second time around if you use error/default.html.
For a reference list of status and messages, see Apache2::Controller.
Since render_fast() is incompatible if a template rendering error occurs, render_fast() turns off the use of error() and relies on standard Apache2 error messages (or the custom message set in the exception object) and relies on the browser to display them.
detect_template
This is called internally by the render methods, but you can use it to figure out the default template from where you are.
To override the auto-select template, just set $self->{template} before you call <render()>.
It looks for templates in a computed directory. The directory where it looks will always be the directory set with the A2CRenderTemplateDir directive in the config file, appended with the current request location, i.e. the directory of the Location directive in the config file, appended with relative_uri, appended with method name and '.html'.
A2CRenderTemplateDir + location + relative_uri + method.htmlFor example, the sequence in SYNOPSIS above renders the file /var/myapp/templates/foo/default.html .
Suppose the dispatch class above dispatches sub-path uris starting with 'bar/biz' to another controller. That controller would look for templates in the directory /var/myapp/templates/foo/bar/biz/methodname.html.
Example:
Request: http://myserver.xyz/foo/bar/biz/baz/boz/noz
location = /foo
relative_uri = bar/biz
controller MyApp::C::Foo::Bar::Biz # mapped in your A2C Dispatch
found method = baz
path_args = [ boz, noz ]
template = /var/myapp/templates + /foo + /bar/biz + /baz.html
/var/myapp/templates/foo/bar/biz/baz.html$self->{relative_uri} is the uri relative to the location, so in other words:
location + relative_uri == full uri - path argsSee Apache2::Controller::Dispatch::Simple.
detect_template_include_path
Like <detect_template()>, this detects the appropriate include path for the template toolkit object, sets it as <$self-{template_include_path}>> and returns it.
This is the directive A2CRenderTemplateDir plus the <Location>. So if you set up your handler to process everything under location /render, and A2CRenderTemplateDir was /var/www/mytemplates, the include_path used for the TT object would be /var/www/mytemplates/render/.
get_tt_obj
Get the Template object set up with the appropriate include directory set from the directive <A2CRenderTemplateDir>.
Directive A2CRenderTemplateOpts sets default new() options for Template.
SEE ALSO
Apache2::Controller::Render::Template
AUTHOR
Mark Hedges, <hedges at--! scriptdolphin.org>
COPYRIGHT & LICENSE
Copyright 2008 Mark Hedges, all rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.