Bitrix Framework

Starting from version 14.0.0, the tab SEO is available in the editing form of the infoblock, its sections, and elements. This functionality is based on the following techniques:

• Storage – meaning a mechanism of inherited properties (property values apply top to bottom over the infoblock hierarchy: from infoblock through sections down to an element);
• Template engine is a template builder that uses substitutions and functions.

Let us consider each of these techniques in more detail.

Storage

All templates to be inherited by the calculated inherited properties are stored in the table b_iblock_iproperty. It is a single table that stores templates for three entities: elements, sections, and infoblocks.

Templates are linked to an infoblock, section, or element using two fields: ENTITY_TYPE and ENTITY_ID. In order to determine which templates should be used for each entity, an internal search by existing infoblock tables is performed. Calculated values are stored in 3 different tables for elements, sections, and infoblocks separately.

When handling the data of the table b_iblock_iproperty (when we change, delete, or make additions to the template) no calculations are made, only the reset of values calculated previously. The calculation operation is postponed until the values are called for (read). At this time, templates are searched from bottom to top over the infoblock hierarchy (for an element, these will be templates of the element proper, its sections (up to the root), and infoblock templates). After that, the templates will be calculated and the obtained values will be stored in cache tables to be retrieved during subsequent read operations.

Classes of inherited properties use all of the capacity of object-oriented programming and belong to a new D7 core. They are in the name space of Bitrix\Iblock\InheritedProperty and are pretty easy to use:

use Bitrix\Iblock\InheritedProperty; 

//OOP  ElementTemplates or SectionTemplates or IblockTemplates )) 
$ipropTemplates = new InheritedProperty\ElementTemplates($IBLOCK_ID, $ELEMENT_ID);
//Install template for an element
$ipropTemplates->set(array(
         "MY_PROP_CODE" => "{=this.Name}",
         “SOME_CODE" => "", //Delete template
));
//Obtain templates for "editing" 
$templates = $ipropTemplates->findTemplates();
//Delete all own element templates
$ipropTemplates->delete();

//OOP  ElementValues or SectionValues or IblockValues )) 
$ipropValues = new InheritedProperty\ElementValues($IBLOCK_ID, $ELEMENT_ID);
//Obtain values 
$values = $ipropValues->getValues();
echo $values [" MY_PROP_CODE "]; 
//Reset cache
$ipropValues->clearValues(); 

• Create a class instance depending on the entity type (for elements it will be ElementTemplates, for sections - SectionTemplates and for infoblock - IblockTemplates).
• Use the set method for template handling.
  Note: The set method is currently used in the methods Add and Update of the classes CIBlock, CIBlockSection and CIBlockElement (the field IPROPERTY_TEMPLATESis processed).

• Use the method getValues (it can be found in infoblock components) in order to display data calculated during selection according to set templates.
• The method clearValues permits you to reset the cached values and recalculate.

Templates

Templates are built irrespective of the storage mechanism, and thus dynamic forms may be used. The following components are used to build a template:

• First, it is just a text to be calculated into the same simple text.
• Second, the substitutions which start inside curly brackets with an equal sign (e.g., {=this.Name}). This pseudoobjective syntaxis permits you to implement an economic model with pending data queries. The template may use the following areas: this, parent, sections, iblock, property or catalog. Fields can be very different: name, code, previewtext, detailtext, property_CODE, etc. (See files with classes in the folder /bitrix/modules/iblock/lib). The number of DB queries directly depends on the number of areas used in the template.
• Third, the functions (e.g., {=concat " \ " "!" iblock.name sections.name this.name}). There is a set of built-in functions (upper, lower, translit, concat, limit, contrast, min, max и distinct) and the event OnTemplateGetFunctionClass, which permits you to write an own function.

Templates can have modifiers: lower casing (/l) and transliteration (/t-). They are displayed in separate checkboxes in the SEO tab interface.

Furthermore, all templates support nesting. For example:

//For an element, a preview and detailed descriptions of its section are selected, then
//first 50 words are selected. After that, they joined with the first 50 words of the element preview.
//Out of them, 20 of the most contrasted words are selected, and all of them are converted to lower case.


{=lower {=contrast 20 " .,?!" {=limit 50 " .,?!" this.previewtext} {=limit 50 " .,?!" parent.previewtext parent.detailtext}}}

Let us have a look at the template code:

use Bitrix\Iblock\Template;
//Connect the infoblock module.
if (\Bitrix\Main\Loader::includeModule('iblock'))
{
      //Set a template.
      $template = "Name: {=this.Name}. Code:{=this.code}";
      //We will take the source data from the element.
      $entity = new Template\Entity\Element($ELEMENT_ID);
      //Do not forget about safety.
      echo \Bitrix\Main\Text\String::htmlEncode(
              //Calculate value according to the template.
              Template\Engine::process($entity, $template) 
     );
}

The entity object must be created. Parsing and template calculation are covered with the process, static method to which entity and template are submitted. The method process can also be used in the cycle with one entity and different template, and in this case the data will be «reused», i.e. there will be no odd queries. In addition, pay attention to the method htmlEncode, that is used to form safe html.