Cache

<?php
$cache = 'data.txt';
if(date("Ymd", filemtime($cache)) <  date("Ymd") || filesize($cache) < 1):	
 $data = get_data(); // do your thing
  $file = fopen($cache,'w+');
  $text = is_array($data) ? json_encode($data) : $data;
   fwrite($file, $text);
   fclose($file);
else:
   $file = fopen($cache,'w+');
 	 $data = fread($file, filesize($cache));	
   if($data[0] == '{');
     $data = json_decode($data, true);
endif;