NAME
Template::Flute - Modern designer-friendly HTML templating Engine
VERSION
Version 0.0107
SYNOPSIS
use Template::Flute;
my ($cart, $flute, %values);
$cart = [{...},{...}];
$values{cost} = ...
$flute = new Template::Flute(specification_file => 'cart.xml',
template_file => 'cart.html',
iterators => {cart => $cart},
values => \%values,
autodetect => {
disable => [qw/Foo::Bar/],
}
);
print $flute->process();
DESCRIPTION
Template::Flute enables you to completely separate web design and
programming tasks for dynamic web applications.
Templates are designed to be designer-friendly; there's no inline code
or mini templating language for your designers to learn - instead,
standard HTML and CSS classes are used, leading to HTML that can easily
be understood and edited by WYSIWYG editors and hand-coding designers
alike.
An example is easier than a wordy description:
Given the following template snippet:
Mr A Test
someone@example.com
and the following specification:
Processing the above as follows:
$flute = Template::Flute->new(
template_file => 'template.html',
specification_file => 'spec.xml',
);
$flute->set_values({
customer_name => 'Bob McTest',
email => 'bob@example.com',
});;
print $flute->process;
The resulting output would be:
Bob McTest
bob@example.com
In other words, rather than including a templating language within your
templates which your designers must master and which could interfere
with previews in WYSWYG tools, CSS selectors in the template are tied to
your data structures or objects by a specification provided by the
programmer.
Workflow
The easiest way to use Template::Flute is to pass all necessary
parameters to the constructor and call the process method to generate
the HTML.
You can also break it down in separate steps:
1. Parse specification
Parse specification based on your specification format (e.g with
Template::Flute::Specification::XML or
Template::Flute::Specification::Scoped.).
$xml_spec = new Template::Flute::Specification::XML;
$spec = $xml_spec->parse(q{});
2. Parse template
Parse template with Template::Flute::HTML object.
$template = new Template::Flute::HTML;
$template->parse(q{
Cart Example
Name
Quantity
Price
Sample Book
$1
Total
$10
},
$spec);
3. Produce HTML output
$flute = new Template::Flute(template => $template,
iterators => {cart => $cart},
values => {cost => '84.94'});
$flute->process();
CONSTRUCTOR
new
Create a Template::Flute object with the following parameters:
specification_file
Specification file name.
specification_parser
Select specification parser. This can be either the full class name
like MyApp::Specification::Parser or the last part for classes
residing in the Template::Flute::Specification namespace.
specification
Specification object or specification as string.
template_file
HTML template file.
template
Template::Flute::HTML object or template as string.
database
Template::Flute::Database::Rose object.
filters
Hash reference of filter functions.
i18n
Template::Flute::I18N object.
iterators
Hash references of iterators.
values
Hash reference of values to be used by the process method.
auto_iterators
Builds iterators automatically from values.
autodetect
A configuration option. It should be an hashref with a key `disable'
and a value with an arrayref with a list of classes for objects
which should be considered plain hashrefs instead. Example:
my $flute = Template::Flute->new(....
autodetect => { disable => [qw/My::Object/] },
....
);
Doing so, if you pass a value holding a `My::Object' object, and you
have a specification with something like this:
The value will be `$object-'{method}>, not `$object-'$method>.
The object is checked with `isa'.
Classical example: `Dancer::Session::Abstract'.
uri Base URI for your template. This adjusts the links in the HTML tags
`a', `base', `img', `link' and `script'.
METHODS
process [HASHREF]
Processes HTML template, manipulates the HTML tree based on the
specification, values and iterators.
Returns HTML output.
process_template
Processes HTML template and returns Template::Flute::HTML object.
filter ELEMENT VALUE
Runs the filter used by ELEMENT on VALUE and returns the result.
value NAME
Returns the value for NAME.
set_values HASHREF
Sets hash reference of values to be used by the process method. Same as
passing the hash reference as values argument to the constructor.
template
Returns HTML template object, see Template::Flute::HTML for details.
specification
Returns specification object, see Template::Flute::Specification for
details.
SPECIFICATION
The specification ties the elements in the HTML template to the data
(variables, lists, forms) which is added to the template.
The default format for the specification is XML implemented by the
Template::Flute::Specification::XML module. You can use the
Config::Scoped format implemented by
Template::Flute::Specification::Scoped module or write your own
specification parser class.
Possible elements in the specification are:
container
The first container is only shown in the output if the value
`billing_address' is set:
The second container is shown if the value `warnings' or the value
`errors' is set:
list
separator
Separator elements for list are added after any list item in the
output with the exception of the last one.
Example specification, HTML template and output:
KEY
|
FOO
|
BAR
param
Param elements are replaced with the corresponding value from the
list iterator.
The following operations are supported for param elements:
append
Appends the param value to the text found in the HTML template.
toggle
Without target attribute, it only shows corresponding HTML
element if param value is set. Wiht target attribute, it simply
toggles the target attribute.
Other attributes for param elements are:
filter
Applies filter to param value.
increment
Uses value from increment instead of a value from the iterator.
value
Value elements are replaced with a single value present in the
values hash passed to the constructor of this class or later set
with the set_values method.
The following operations are supported for value elements:
append
Appends the value to the text found in the HTML template.
hook
Insert HTML residing in value as subtree of the corresponding
HTML element. HTML will be parsed with XML::Twig. See INSERT
HTML for an example.
toggle
Only shows corresponding HTML element if value is set.
Other attributes for value elements are:
filter
Applies filter to value.
include
Processes the template file named in this attribute. This
implies the hook operation.
form
Form elements are tied through specification to HTML forms.
Attributes for form elements in addition to `class' and `id' are:
link
The link attribute can only have the value `name' and allows to
base the relationship between form specification elements and
HTML form tags on the name HTML attribute instead of `class',
which is usually more convenient.
input
filter
sort
i18n
SIMPLE OPERATORS
append
Appends the value to the text inside a HTML element or to an attribute
if `target' has been specified. This can be used in `value' and `param'
specification elements.
The example shows how to add a HTML class to elements in a list:
HTML:
XML:
CONDITIONALS
Display image only if present
In this example we want to show an image only on a certain condition:
HTML:
XML:
Source code:
if ($organization eq 'Big One') {
$values{banner} = 'banners/big_one.png';
}
Display link in a list only if present
In this example we want so show a link only if an URL is available:
HTML:
XML:
Source code:
@records = ({name => 'Link', url => 'http://localhost/'},
{name => 'No Link'},
{name => 'Another Link', url => 'http://localhost/'},
);
$flute = Template::Flute->new(specification => $spec_xml,
template => $template,
iterators => {links => \@records});
$output = $flute->process();
ITERATORS
Template::Flute uses iterators to retrieve list elements and insert them
into the document tree. This abstraction relieves us from worrying about
where the data actually comes from. We basically just need an array of
hash references and an iterator class with a next and a count method.
For your convenience you can create an iterator from
Template::Flute::Iterator class very easily.
DROPDOWNS
Iterators can be used for dropdowns (HTML