PHP caching samples

304_file.php

<?php
// Return 304 when files are not changed
if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) && 
    strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) >= filemtime(__FILE__))
{
    header('HTTP/1.0 304 Not Modified');
    exit;
}

api.php

<?php
require_once('config.php');
require_once('model_tablename.php');

header('Content-Type: application/json');
header('Cache-Control: no-cache');

if(@$_GET['requests']){
  updateTablenameRequests($_GET['id'],$_GET['requests']);
}
if(@$_GET['id']){
  echo getTablenameRow($_GET['id']);  
}else{
  echo getTablenameRows();
}

config.php

<?php // Configuration
/* PDO
$provider = 'PDO';
$dbhost = dirname(__FILE__);
$dsn = "sqlite:".$dbhost;

/* Memory
$provider = 'SQLite3';
$dsn = "memory:";
*/

$provider = 'SQLite3';
$dbhost = '';
$dbname = "SQLite3.db";
$dsn = $dbname;

// Test the connection
try {
  $db = new $provider($dsn);
} catch (Exception $e) {
    header('HTTP/1.0 500 Internal Server Error');
    echo $e->getMessage();
}

generateTablenameRows.php

<?php
require_once('config.php');
require_once('model_tablename.php');

header('Content-Type: application/json');
header('Cache-Control: no-cache');

generateTablenameRows(@$_GET['from'],@$_GET['rows']);
echo getTablenameRows();

max-age0.php

<?php
require_once('config.php');
require_once('model_tablename.php');

header('Content-Type: application/json');
header('Cache-Control: max-age=0');

if(@$_GET['requests']){
  updateTablenameRequests($_GET['id'],$_GET['requests']);
}
if(@$_GET['id']){
  echo getTablenameRow($_GET['id']);  
}else{
  echo getTablenameRows();
}

max-age0must-revalidate.php

<?php
require_once('config.php');
require_once('model_tablename.php');

header('Content-Type: application/json');
header('Cache-Control: max-age=0, must-revalidate');

if(@$_GET['requests']){
  updateTablenameRequests($_GET['id'],$_GET['requests']);
}
if(@$_GET['id']){
  echo getTablenameRow($_GET['id']);  
}else{
  echo getTablenameRows();
}

model_tablename.php

<?php
// Install
@$db->query('CREATE TABLE IF NOT EXISTS tablename (id int, requests int, sometext TEXT, PRIMARY KEY (id))');

function json_cache($query, $data){
    $new = json_encode($data);

    $cached = join(DIRECTORY_SEPARATOR,array(sys_get_temp_dir(),md5($query)));
    // Save query result as file
    if(md5_file($cached) != md5($new))
      file_put_contents($cached,$new);

    header('Last-Modified: ' . gmdate('D, d M Y H:i:s T', filemtime($cached)));

    // Check if the cached file ir modified
    if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) && 
        strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) >= filemtime($cached) &&
        strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) >= filemtime(__FILE__))
    {
        // Not Modified:Return the 304
        header('HTTP/1.0 304 Not Modified');
        header('X-cached: '.$cached);
      // Or ... open cached file
      // return = file_get_contents($cached);
        exit;
    }
    // Modified, return the result
    return $new;
}

function generateTablenameRows($from, $rows) {
    if(!@$to)$to = 100;
    for($i=$from+1;$i<=$from+$to;$i++){
      $id = $i;
      createTablenameRow($i,$i, substr(str_shuffle(MD5(microtime())), 0, 10));
    }
    header('X-generated: '.$i);
}

function createTablenameRow($id,$requests,$sometext) {
    global $db;
    $provider = get_class($db);
    $query = 'INSERT INTO tablename (id, requests, sometext) VALUES(:id, :requests, :sometext)';
    $stmt = $db->prepare($query);
    $stmt->bindValue(':id',$id,constant(strtoupper($provider).'_INTEGER'));
    $stmt->bindValue(':requests',$requests,constant(strtoupper($provider).'_INTEGER'));
    $stmt->bindValue(':sometext',$sometext,constant(strtoupper($provider).'_TEXT'));
    if($res = $stmt->execute()){
      $data = $res->fetchArray();

      return json_cache($query, $data);
    }
}

function getTablenameRow($id) { 
    global $db;
    $provider = get_class($db);
    $query = 'SELECT * FROM tablename WHERE id = :id';
    $stmt = $db->prepare($query);
    $stmt->bindValue(':id',$id,constant(strtoupper($provider).'_INTEGER'));
    $res = $stmt->execute();

  // res, query
    $data = array(); 
    $i = 0; 

    while($row = $res->fetchArray(constant(strtoupper($provider).'_ASSOC'))){ 
      if(!isset($row['id'])) continue; 
      $data[$i]['id'] = $row['id']; 
      $data[$i]['requests'] = $row['requests']; 
      $i++; 
    }
    header('X-resulted-rows: '.$i);
  
    return json_cache($query, $data);
}
function updateTablenameRequests($id,$requests) { 
    global $db;
    $provider = get_class($db);
    $query = 'UPDATE tablename SET requests=:requests WHERE id = :id';
    $stmt = $db->prepare($query);
    $stmt->bindValue(':id',$id,constant(strtoupper($provider).'_INTEGER'));
    $stmt->bindValue(':requests',$requests,constant(strtoupper($provider).'_INTEGER'));
    $res = $stmt->execute();

    $data = $res->fetchArray();
  
    return json_cache($query, $data);
}

function deleteTablenameRow($id) { 
    global $db;
    $provider = get_class($db);
    $query = 'DELETE FROM tablename WHERE id = :id';
    $stmt = $db->prepare($query);
    $stmt->bindValue(':id',$id,constant(strtoupper($provider).'_INTEGER'));
    $res = $stmt->execute();

    $data = $res->fetchArray();
  
    return json_cache($query, $data);
}

function getTablenameRows() { 
    global $db;
    $provider = get_class($db);
    $query = 'SELECT * FROM tablename';
    $stmt = $db->prepare($query);
    $res = $stmt->execute();

  // res, query
    $data = array(); 
    $i = 0; 

    while($row = $res->fetchArray(constant(strtoupper($provider).'_ASSOC'))){ 
      if(!isset($row['id'])) continue; 
      $data[$i]['id'] = $row['id']; 
      $data[$i]['requests'] = $row['requests']; 
      $i++; 
    }
    header('X-resulted-rows: '.$i);
  
    return json_cache($query, $data);
}

no-cache.php

<?php
require_once('config.php');
require_once('model_tablename.php');

header('Content-Type: application/json');
header('Cache-Control: no-cache');

if(@$_GET['requests']){
  updateTablenameRequests($_GET['id'],$_GET['requests']);
}
if(@$_GET['id']){
  echo getTablenameRow($_GET['id']);  
}else{
  echo getTablenameRows();
}

no-store.php

<?php
require_once('config.php');
require_once('model_tablename.php');

header('Content-Type: application/json');
header('Cache-Control: no-store');

if(@$_GET['requests']){
  updateTablenameRequests($_GET['id'],$_GET['requests']);
}
if(@$_GET['id']){
  echo getTablenameRow($_GET['id']);  
}else{
  echo getTablenameRows();
}