Your composer.json should have ext-memcached listed in it but it won't install, it'll just throw an error if it's missing. Here's various ways to get it:
Windows Binary Route
AFAIK as of 2018 there is no binary Windows port of JUST Memcached for PHP 7
But there is a pre-packaged version in Laragon or alternatively Winginx
Windows DLL Route
There's a handful of people offering compiled DLLs on github (64-bit, and thread-safe offered)
Windows Subsystem For Linux Route
ubuntu
sudo add-apt-repository ppa:ondrej/php
sudo apt-get update
sudo apt install php-memcached
Restart php fpm if using it sudo service php7.2-fpm restart
Compile from Source Route
You can compile the php bindings but the windows package of memcached has been broken for 4 years (as of 2018)
Local-Only Cache Files Polyfill Route
Here's a dirty wrapper around Memcached called StaticCache you can use in a pinch to read/write values from disk. It's obviously way slower than memcached so it's only meant to be a shoe-in for Windows development. If you get fancy, you could define this as a polyfill by the same name
function StaticCacheClear()
{
foreach (scandir(sys_get_temp_dir()) as $file) {
if (StringBeginsWith($file, "staticcache"))
{
$path = sys_get_temp_dir() ."/". $file;
unlink($path);
}
}
global $Memcache;
if ($Memcache) $Memcache->flush();
}
// REMOVE if you don't want a global way to clear cache
if (isset($_GET['clear_static_cache'])) {
StaticCacheClear();
}
function MemcacheGet($key)
{
global $Memcache;
$value = $Memcache ? $Memcache->get($key) : (file_exists($key)?file_get_contents($key):null);
return !$Memcache? $value : (Memcached::RES_NOTFOUND === $Memcache->getResultCode() ? null : $value);
}
function StaticCacheKey($key)
{
global $Memcache;
$cacheVersion = "MY_APP_VERSION_HERE";
$uniqueKey = "staticcache_{$key}_" . date("Ymd") . "$cacheVersion.cache";
$filename = sanitize_file_name($uniqueKey);
$filename = sys_get_temp_dir() . '/' . $filename;
return $Memcache ? $uniqueKey : $filename;
}
function StaticCacheWrite($key, $value)
{
global $Memcache;
if (isset($_GET['disable-cache'])) return null;
if ($Memcache)
$Memcache->set(StaticCacheKey($key), serialize($value));
else
file_put_contents(StaticCacheKey($key), serialize($value));
}
function StaticCacheRead($key)
{
global $Memcache;
$key = StaticCacheKey($key);
$value = MemcacheGet($key);
return $value !== null ? unserialize($value) : null;
}
