/**
* Wraps a credential provider and saves provided credentials in an
* instance of Aws\CacheInterface. Forwards calls when no credentials found
* in cache and updates cache with the results.
*
* Defaults to using a simple file-based cache when none provided.
*
* @param callable $provider Credentials provider function to wrap
* @param CacheInterface $cache (optional) Cache to store credentials
* @param string|null $cacheKey (optional) Cache key to use
*
* @return callable
*/
public static function cache(callable $provider, CacheInterface $cache, $cacheKey = null)
{
$cacheKey = $cacheKey ?: 'aws_cached_credentials';
return function () use($provider, $cache, $cacheKey) {
$found = $cache->get($cacheKey);
if ($found instanceof CredentialsInterface && !$found->isExpired()) {
return Promise\promise_for($found);
}
return $provider()->then(function (CredentialsInterface $creds) use($cache, $cacheKey) {
$cache->set($cacheKey, $creds, null === $creds->getExpiration() ? 0 : $creds->getExpiration() - time());
return $creds;
});
};
}
public function determineBucketRegionAsync($bucketName)
{
if ($cached = $this->cache->get($this->getCacheKey($bucketName))) {
return Promise\promise_for($cached);
}
return $this->lookupBucketRegion($bucketName)->then(function ($region) use($bucketName) {
$this->cache->set($this->getCacheKey($bucketName), $region);
return $region;
});
}