How to add caching to php script?

Question

PHP

Hello, there is a script (I have 8 of them on the site), because of it the site opens for more than 3 seconds, which was reported to me by Yandex today, I wrote to the hoster, the hoster replied that the matter was in these scripts, it was necessary to cache them.

<?php

    $map = function($array, $from, $to){
        $result = [];
        if(!empty($array) && is_array($array)){
            foreach ($array as $element) {
                $key = $element[$from]?:null;
                $value = $element[$to]?:null;
                if($key && $value){
                    $result[$key] = $value;
                }
            }
        }
        return $result;
    };

   $airlines = $map(json_decode(file_get_contents('http://aviaciya.com/json/airlines.json'), true), 'iata', 'name');
$cit=json_decode(file_get_contents("http://avia-avia.ru/json/cities.json")); $cities=array(); foreach($cit as $val) { if(property_exists($val->name_translations,"ru")) $cities[$val->code]=$val->name_translations->ru;}

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, "https://api.travelpayouts.com/v1/prices/cheap?origin=MOW&destination=AER&limit=30&token=**************");
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
    curl_setopt($ch, CURLOPT_HEADER, FALSE);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array("X-Access-Token: *************"));
    $response = curl_exec($ch);
    curl_close($ch);
    $products=json_decode($response,true);
    $replace_value = function($key, $val) use ($cities, $airlines){
        $response = $val;
        switch($key){case 'destination':
                $response = $cities[$val];break;
                case 'origin':
                $response = $cities[$val];break;
            case 'airline':
                $response = $airlines[$val];
                break;
        }
        return $response;
    }

    ?>








    <div id="kurorty" class="container-fluid">

     <div class="table-responsive"><h5>Авиабилеты Москва Адлер</h5><table class="table table-hover">
        <thead>
          <tr>
            <th style="text-align: center;"> Пункт отправления</th>
            <th style="text-align: center;">Пункт назначения </th>
            <th class="mob" style="text-align: center;"> Авиакомпания</th> <th style="text-align: center;">Цена, р.</th> <th class="mob" style="text-align: center;">Дата вылета</th>
    <th class="mob" style="text-align: center;">Обратная дата</th>
    <th> </th>
          </tr>
        </thead>    <tbody>
    <?php
    if(isset($products['data']) && is_array($products['data'])) {
    foreach ($products['data'] as $key => $data) {
    foreach ($data as $destination => $row) {
    if (preg_match('/[A-Z]{3}/i', $key)) {
    ?>
    <tr>
    <td>&nbsp; <?php echo Москва ;?>&nbsp;</td>
            <td>&nbsp; <?= $replace_value('destination',$key) ? $replace_value('destination', $key) : "<b>" .'Обновл.'. "</b>"; ?>&nbsp; </td>

         <td class="mob"><img height="50" alt="" width="120" src="http://pics.avs.io/180/70/<?= $row['airline']?>.png" /></td>
    <td><?php echo $replace_value('price', $row['price']); ?>&nbsp;  RUB &nbsp; </td> 
    <td class="mob"><?php echo $replace_value('departure_at', substr($row['departure_at'], 0, 10)); ?></td>
    <td class="mob"><?php echo $replace_value('return_at', substr($row['return_at'], 0, 10)); ?></td>
          <td><a rel="nofollow" role="button" alt="авиабилеты Москва <?php echo $replace_value('destination',$key); ?>" title="авиабилеты Москва <?php echo $replace_value('destination',$key); ?>" href="https://bilety.avia-avia.ru/flights/?origin_iata=MOW&destination_iata=<?=$key?>&depart_date=<?=substr($row['departure_at'], 0, 10)?>&return_date=<?=substr($row['return_at'], 0, 10)?>&adults=1&children=0&infants=0&trip_class=0&marker=87111&with_request=true">Поиск</a></td></tr>
    <?php
    }
    }
    }
    }
    ?>  </tbody>
      </table>
    </div>

I no longer use this line in subsequent scripts

$airlines = $map(json_decode(file_get_contents('http://aviaciya.com/json/airlines.json'), true), 'iata', 'name');
$cit=json_decode(file_get_contents("http://avia-avia.ru/json/cities.json")); $cities=array(); foreach($cit as $val) { if(property_exists($val->name_translations,"ru")) $cities[$val->code]=$val->name_translations->ru;}

Only this line changes in scripts, it is responsible for which directions to take data from.

curl_setopt($ch, CURLOPT_URL, "https://api.travelpayouts.com/v1/prices/cheap?origin=MOW&destination=AER&limit=30&token=**************");

It is because of him that the site opens for more than 3 seconds. I received a notification from Yandex yesterday about this.
The owner of Api wrote (There is nothing complicated. Just save the api response to a file on your server and read it. Updating once an hour, since the data changes every 2 hours)
He also gave a link to the answer to my question, he said there is that's what I need (

https://ru.stackoverflow.com/questions/490089/%D0%9A%D1%8D%D1%88%D0%B8%D1%80%D0%BE%D0%B2%D0%B0%D0%BD%D0%B8%D0%B5-json-%D0%BE%D1%82%D0%B2%D0%B5%D1%82%D0%B0-%D0%B8%D0%B7-instagram

)
Another kind person looked at this link and said "

The script is extremely simple, you take json and save it, there are a couple of lines to fix your script. And in your code, only the url will need to be changed. The point is that you need to save $products to a file and read from that file.

"Everyone is so simple, only for me it's a rattling forest. Please help.

Answer 1

Well, in general, the solution is this: we write a script that will save json to a file, we pull this script with a cron, and in the main script we start using local json.