Opt Instruction Url

From Invenzzia wiki

Opt_Instruction_Url
Project	Open Power Template 2
Type	Instruction
Author	Tomasz Jędrzejewski
Website	http://www.invenzzia.org/
License	New BSD License
Status	No information

This instruction is an URL routing helper for use with various frameworks. It provides an alternative way to create dynamic URL-s with the framework router.

The source code

The source code for the instruction can be found below. You can either register it manually or as an OPT plugin.

<?php
 
class Opt_Instruction_Url extends Opt_Compiler_Processor
{
    const ROUTING_FUNCTION = 'myRoutingFunction';
    static private $_cnt = 0;
 
    public function configure()
    {
        $this->_addInstructions(array('opt:url'));
    } // end configure();
 
    public function processNode(Opt_Xml_Node $node)
    {
        // Prevent from adding an attribute to OPT tags
        if(!$node->getParent() instanceof Opt_Xml_Element)
        {
            throw new Opt_InstructionInvalidParent_Exception($node->getXmlName(), 'any non-OPT tag');
        }
        if($this->_compiler->isNamespace($node->getParent()->getNamespace()))
        {
            throw new Opt_InstructionInvalidParent_Exception($node->getXmlName(), 'any non-OPT tag');
        }
 
        // Parse the instruction attributes
        $params = array(
            'attribute' => array(0 => self::OPTIONAL, self::HARD_STRING, 'href'),
            '__UNKNOWN__' => array(0 => self::OPTIONAL, self::EXPRESSION)
        );
        $vars = $this->_extractAttributes($node, $params);
 
        if($node->hasChildren())
        {
            $attributes = $node->getElementsByTagNameNS('opt', 'attribute', false);
 
            if(sizeof($attributes) == 0)
            {
                $this->_buildCode($node, $vars, $params['attribute']);
                return;
            }
            foreach($attributes as $attr)
            {
                $attr->set('attributeValueStyle', Opt_Instruction_Attribute::ATTR_RAW);
            }
            $node->set('priv:url', $vars);
            $node->set('priv:attribute', $params['attribute']);
            $node->set('postprocess', true);
            $this->_process($node);
        }
        else
        {
            $this->_buildCode($node, $vars, $params['attribute']);
        }
    } // end processNode();
 
    public function postprocessNode(Opt_Xml_Node $node)
    {
        $attribute = $node->get('call:attribute');
        $vars = $node->get('priv:url');
        if(is_null($attribute))
        {
            $this->_buildCode($node, $vars, $node->get('priv:attribute'));
            return;
        }
        // Ok, we have the opt:attribute instructions right there
        $code = ' $_routing_'.(self::$_cnt).' = array(';
        foreach($vars as $name => $value)
        {
            $code .= $name.' => '.$value.',';
        }
        $code .= '); ';
        foreach($attribute as $attr)
        {
            $attr->set('nophp', true);
            $code .= $attr->buildCode(Opt_Xml_Buffer::ATTRIBUTE_BEGIN);
            $code .= ' $_routing_'.(self::$_cnt).'['.$attr->buildCode(Opt_Xml_Buffer::ATTRIBUTE_NAME).'] = '.$attr->buildCode(Opt_Xml_Buffer::ATTRIBUTE_VALUE).'; '.$attr->buildCode(Opt_Xml_Buffer::ATTRIBUTE_END);
        }
        $node->getParent()->addAfter(Opt_Xml_Buffer::TAG_BEFORE, $code);
 
        // Create an attribute for the parent.
        $attribute = new Opt_Xml_Attribute($node->get('priv:attribute'), null);
        $attribute->addAfter(Opt_Xml_Buffer::ATTRIBUTE_VALUE, ' echo '.self::ROUTING_FUNCTION.'($_routing_'.(self::$_cnt).'); unset($_routing_'.(self::$_cnt).');');
 
        $node->getParent()->addAttribute($attribute);
        self::$_cnt++;
 
        // Clean
        $node->set('call:attribute', null);
        $node->set('priv:url', null);
        $node->set('priv:attribute', null);
    } // end postprocessNode();
 
    private function _buildCode(Opt_Xml_Node $node, Array $vars, $attributeName)
    {
        // Build the code
        $code = 'echo '.self::ROUTING_FUNCTION.'( array (';
        foreach($vars as $name => $value)
        {
            $code .= $name.' => '.$value.',';
        }
        $code .= '))';
 
        // Create an attribute for the parent.
        $attribute = new Opt_Xml_Attribute($attributeName, null);
        $attribute->addAfter(Opt_Xml_Buffer::ATTRIBUTE_VALUE, $code);
 
        $node->getParent()->addAttribute($attribute);
    } // end _buildCode();
} // end Opt_Instruction_Url;

Manual installation instructions:

1. Copy the file somewhere.
2. Register the class in the autoloader: Opl_Loader::mapAbsolute('Opt_Instruction_Url', './some/path');
3. Register the instruction in OPT: $tpl->register(Opt_Class::OPT_INSTRUCTION, 'Url');
4. Be sure to modify the ROUTING_FUNCTION constant so that it points to the router.

Plugin installation:

1. Save the code above as instruction.Url.php in your OPT plugin directory.
2. Ensure that your script is configured to load plug-ins.
3. Be sure to modify the ROUTING_FUNCTION constant so that it points to the router.
4. Enjoy.

The usage

The instruction is really simple in use. Below you can find a template:

<a>
    <opt:url foo="$foo" bar="$bar" />
    Foo
</a>

This will give you (the exact address depends on your router):

<a href="/foo/value/bar/value/">
Foo
</a>

By default, the instruction creates href attribute, but you can freely use it for other purposes:

<form method="post">
    <opt:url foo="$foo" bar="$bar" attribute="action" />
    Foo
</form>

The instruction can also load the attributes from a section:

<a>
    <opt:url str:foo="foo">
        <opt:attribute name="$extra.name" value="$extra.value" opt:section="extra" />
    </opt:url>
    Foo
</a>