I wonder if it's should be treated like a BC break. ping @nicolas-grekas

Looks like a BC break to me, but might be worth doing anyway instead of silently ignoring the call.

Looks like a BC break to me, but might be worth doing anyway instead of silently ignoring the call.

Small typo, should be $zookeeperServer

The method refresh is called internally when calling acquire with a non-null TTL (which is the default case when using the Factory with default arguments)

When using a NotExpirableStore (like flock) the logger will be full of notice.
Same comment when combining a non-expirable store and expirable one (flock + redis for instance)

IMHO You should either silent this exception when calling acquire or update the factory to set a null TTL when the store does not support expiration.

Would be great from a user point of view to known whether or not the store supports expiration.

interface StoreInterface {
  public function save(Key $key);
  public function waitAndSave(Key $key);
  public function delete(Key $key);
  public function exists(Key $key);
}

interface ExpirableStoreInterface extends StoreInterface {
  public function supportsExpiration(): bool
  public function putOffExpiration(Key $key, $ttl);
}