init.php

add custom field before send event

\Bitrix\Main\Loader::includeModule('iblock');
\Bitrix\Main\Loader::includeModule('catalog');

//Добавляем реальный путь к товару для подписки
AddEventHandler('main', 'OnBeforeEventSend', Array("ChangeProductSubscribe", "SubscribeOnBeforeEventSend"));

class ChangeProductSubscribe
{
    function SubscribeOnBeforeEventSend(&$arFields, &$arTemplate)
    {
        if ($arTemplate['ID'] == 28) {
            //ИБ товаров
            $intIBlockID = 1;

            //получаем ID товара по ТП
            $intSkuID = $arFields['ITEM_ID'];
            $arProductProp = \CCatalogSku::GetProductInfo($intSkuID);

            //получаем DETAIL_PAGE_URL
            if (is_numeric($arProductProp['ID'])) {
                $strProductUrl = '';
                $arSelect = array(
                    "IBLOCK_ID",
                    "ID",
                    "DETAIL_PAGE_URL"
                );
                $arFilter = array(
                    "IBLOCK_ID" => $intIBlockID,
                    "ID" => $arProductProp['ID'],
                );
                $res = \CIBlockElement::GetList(
                    array(),
                    $arFilter,
                    false,
                    array("nPageSize" => 1),
                    $arSelect
                );
                while ($ob = $res->GetNextElement()) {
                    $arFieldsList = $ob->GetFields();
                    $strProductUrl = $arFieldsList['DETAIL_PAGE_URL'];
                }

                //Пишем DETAIL_PAGE_URL в шаблон письма о пуступлении товара
                if(!empty($strProductUrl)){
                    $arFields['FULL_DETAIL_PAGE'] = $_SERVER['SERVER_NAME'] . $strProductUrl;
                }
            }
        }
    }
}


//add all product property min price
<?
$arResult = array();
$arSelect = array(
    "IBLOCK_ID",
    "ID",
    "NAME"
);
$arFilter = array(
    "IBLOCK_ID"=>1
);
$res = CIBlockElement::GetList(
    array("ID" => "ASC"),
    $arFilter,
    false,
    array(),
    $arSelect
);
while($ob = $res->GetNextElement())
{
    $arFields = $ob->GetFields();
    $arResult[] = $arFields;

}

if(!empty($arResult)){

    foreach ($arResult as $arItem){
        $intProductID = $arItem['ID'];

        if(is_numeric($intProductID)){
            
            $arOffersList = \CCatalogSKU::getOffersList($intProductID, 1, array(), array('CATALOG_QUANTITY', 'CATALOG_PRICE_1'), array());

            $intMinPrice = 0;
            if(!empty($arOffersList)){

                foreach ($arOffersList[$intProductID] as $arOffer){

                    if($intMinPrice == 0){
                        $intMinPrice = $arOffer['CATALOG_PRICE_1'];
                        continue;
                    }
                    if($intMinPrice > $arOffer['CATALOG_PRICE_1']){
                        $intMinPrice = $arOffer['CATALOG_PRICE_1'];
                    }
                }
            }

            CIBlockElement::SetPropertyValuesEx($intProductID, 1, array('MIN_PRICE' => intval($intMinPrice)));
        }

    }

}
?>

Add MinPrice property to product

<?php
use Bitrix\Main\Loader;
use Bitrix\Main\Diag\Debug;

Loader::includeModule('iblock');
Loader::includeModule('catalog');

AddEventHandler('iblock', 'OnAfterIBlockElementAdd', 'setProductMinPrice');
AddEventHandler('iblock', 'OnAfterIBlockElementUpdate', 'setProductMinPrice');

if (!function_exists('setProductMinPrice')) {
function setProductMinPrice(&$arFields)
{
    $intProductID = $arFields['ID'];
    //Debug::writeToFile($arFields, '$arFields', '__product_add.log');

    if(is_numeric($intProductID)){

        $arOffersList = \CCatalogSKU::getOffersList($intProductID, 1, array(), array('CATALOG_QUANTITY', 'CATALOG_PRICE_1'), array());

        $intMinPrice = 0;
        if(!empty($arOffersList)){

            foreach ($arOffersList[$intProductID] as $arOffer){
                if($intMinPrice == 0){
                    $intMinPrice = $arOffer['CATALOG_PRICE_1'];
                    continue;
                }
                if($intMinPrice > $arOffer['CATALOG_PRICE_1']){
                    $intMinPrice = $arOffer['CATALOG_PRICE_1'];
                }
            }
        }

        CIBlockElement::SetPropertyValuesEx($intProductID, 1, array('MIN_PRICE' => intval($intMinPrice)));
    }
}
}

Add property after update element

\Bitrix\Main\Loader::includeModule('iblock');

//Делаем не активным товар, если нет предложений
AddEventHandler("iblock", "OnAfterIBlockElementUpdate", Array("UpdateElementIBlock", "OnAfterIBlockElementUpdateHandler"));

class UpdateElementIBlock
{
    function OnAfterIBlockElementUpdateHandler(&$arFields)
    {
        //ИБ товаров
        $intIBlockID = 1;

        if($arFields["RESULT"] && $arFields['IBLOCK_ID'] == $intIBlockID){

            $intProductID = $arFields['ID'];
            if(is_numeric($intProductID)){

                //получаем все ТП товара $intProductID
                $arOffersList = \CCatalogSKU::getOffersList($intProductID, $intIBlockID, array(), array('CATALOG_QUANTITY'), array());

                if(is_array($arOffersList)){
                    $blDisabledSKU = true;

                    foreach ($arOffersList[$intProductID] as $arOffer){
                        if($arOffer['CATALOG_QUANTITY'] > 0){
                            $blDisabledSKU = false;
                            break;
                        }
                    }

                    //пишем св-во DISABLED_QUANTITY_SKU
                    if($blDisabledSKU){
                        $mixPropValue = 121;
                    }else{
                        $mixPropValue = false;
                    }
                    CIBlockElement::SetPropertyValuesEx($intProductID, $intIBlockID, array('DISABLED_QUANTITY_SKU' => $mixPropValue));
                }

            }

        }
    }
}

OnEndBufferContent

//change title by all site, out section 6,7 and includes section
AddEventHandler('main', 'OnEndBufferContent', 'setTitlePage');
function setTitlePage(&$strContent)
{
    if (SITE_ID == 's3' && $_REQUEST['CODE'] !== 'tablet_pc' && $_REQUEST['CODE'] !== 'phone')
    {
        $strRequestCode = $_REQUEST['CODE'];

        //by element
        $arItemProp = array();
        $arSelect = array(
            "IBLOCK_ID",
            "ID",
            "IBLOCK_SECTION_ID"
        );
        $arFilter = array(
            "IBLOCK_ID" => 3,
            "ACTIVE_DATE" => "Y",
            "ACTIVE" => "Y",
            "CODE" => $strRequestCode
        );
        $res = CIBlockElement::GetList(
            array("RAND" => "ASC"),
            $arFilter,
            false,
            array("nPageSize" => 1),
            $arSelect
        );
        while ($ob = $res->GetNextElement()) {
            $arFields = $ob->GetFields();
            $arItemProp[] = $arFields;
        }
        $intSearchParentID = $arItemProp[0]['IBLOCK_SECTION_ID'];

        //by section
        if(empty($arItemProp) && !empty($strRequestCode))
        {
            $SectList = CIBlockSection::GetList(
                array("RAND" => "ASC"),
                array(
                    "IBLOCK_ID"=>3,
                    "ACTIVE"=>"Y",
                    "CODE" => $strRequestCode
                ),
                false,
                array(
                    "ID",
                )
            );
            while ($SectListGet = $SectList->GetNext())
            {
                $arSectionProp[]= $SectListGet;
                break;
            }
            $intSearchParentID = $arSectionProp[0]['ID'];
        }

        //parent section
        $arSectionParent = array();
        $navChain = CIBlockSection::GetNavChain(3, $intSearchParentID);
        while ($arNav=$navChain->GetNext()){
            $arSectionParent[] = $arNav;
            break;
        }

        //add title
        if(empty($strRequestCode) || ($arSectionParent[0]['ID'] != 6 && $arSectionParent[0]['ID'] != 7))
        {
            preg_match('#<title>(.*?)</title>#',$strContent,$arSearchFound);
            $strContent = preg_replace('#<title>(.*?)</title>#', '<title>'. $arSearchFound[1] .'. Санкт-Петербург</title>', $strContent);
        }
    }
}

Set notify to Crm

AddEventHandler('iblock', 'OnAfterIBlockElementAdd', 'setNotifyReviewCrm');

function setNotifyReviewCrm(&$arFields)
{
    if($arFields['IBLOCK_ID'] == REVIEW_IBLOCK_ID){

        $strPathWebHook = 'https://you_domain.bitrix24.ru/rest/6/CODE_WEB_HOOK/';
        $strQueryUrl = $strPathWebHook . 'im.notify.system.add';

        // REST Api
        $queryData = http_build_query(array(
            'USER_ID' => 6,
            'MESSAGE' => 'Message custom',
            'MESSAGE_OUT' => '',
            'TAG' => '',
            'SUB_TAG' => '',
            'ATTACH' => Array()
        ));

        $curl = curl_init();
        curl_setopt_array($curl, array(
            CURLOPT_SSL_VERIFYPEER => 0,
            CURLOPT_POST => 1,
            CURLOPT_HEADER => 0,
            CURLOPT_RETURNTRANSFER => 1,
            CURLOPT_URL => $strQueryUrl,
            CURLOPT_POSTFIELDS => $queryData,
        ));
        $strResult = curl_exec($curl);
        curl_close($curl);

//        Debug::writeToFile($strResult, '$strResult', '__test_log123.log');
//https://dev.1c-bitrix.ru/learning/course/?COURSE_ID=93&LESSON_ID=12131
    }
}

Update real path by #tempalte#

//canonical
use \Bitrix\Main\Application;

AddEventHandler('main', 'OnEndBufferContent', 'setCanonical');
if (!function_exists('setCanonical')) {
    function setCanonical(&$strContent)
    {
        $request = Application::getInstance()->getContext()->getRequest();

        if (!$request->isAdminSection()) {
            $strContent = str_replace('#SERVER_HOST_CANONICAL#', $_SERVER['HTTP_HOST'], $strContent);
        }

    }
}