get

Note

This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information.

Retreive a value

public function get(
  string $key,
): Awaitable<string>;

Parameters

• string $key - Name of the key to retreive

Returns

• string - - The Value stored

Examples

Most of the MCRouter examples use MCRouter::get in order to demonstrate other functions of the API. This example calls out get explicitly in its own function to show you how it works. If you try to get on a key that does not exist, an exception will be thrown.

function get_simple_mcrouter(): \MCRouter {
  $servers = Vector {\getenv('HHVM_TEST_MCROUTER')};
  $mc = \MCRouter::createSimple($servers);
  return $mc;
}

async function set_value(
  \MCRouter $mc,
  string $key,
  string $value,
): Awaitable<void> {
  // can also pass optional int flags and int expiration time (in seconds)
  await $mc->set($key, $value);
}

async function get_value(\MCRouter $mc, string $key): Awaitable<?string> {
  $ret = null;
  try {
    $ret = await $mc->get($key);
  } catch (\MCRouterException $ex) { // e.g., exception if key doesn't exist
    \var_dump($ex->getMessage());
  }
  return $ret;
}

<<__EntryPoint>>
async function run(): Awaitable<void> {
  $mc = get_simple_mcrouter();
  $unique_key = \str_shuffle('ABCDEFGHIJKLMN');
  await set_value($mc, $unique_key, "Hi");
  $val = await get_value($mc, $unique_key);
  \var_dump($val);
  // Getting a non-existent key is no good
  $val = await get_value($mc, "THISKEYDOESNOTEXISTIHOPE");
  if (!$val) {
    echo "Key must not have existed\n";
  }
}
```.hhvm.expectf
string(2) "Hi"
string(38) "get failed with result mc_res_notfound"
Key must not have existed
```.example.hhvm.out
string(2) "Hi"
string(38) "get failed with result mc_res_notfound"
Key must not have existed
```.skipif
\Hack\UserDocumentation\API\Examples\MCRouter\skipif();