/**
* Get the region-specific hostname for an operation given a configuration and a bucket name. This ensures we can
* always use an HTTPS connection, even with buckets containing dots in their names, without SSL certificate host
* name validation issues.
*
* Please note that this requires the pathStyle flag to be set in Configuration because Amazon RECOMMENDS using the
* virtual-hosted style request where applicable. See http://docs.aws.amazon.com/AmazonS3/latest/API/APIRest.html
* Quoting this documentation:
* "Although the path-style is still supported for legacy applications, we recommend using the virtual-hosted style
* where applicable."
*
* @param Configuration $configuration
* @param string $bucket
*
* @return string
*/
private function getHostName(Configuration $configuration, $bucket)
{
//
// http://docs.aws.amazon.com/general/latest/gr/rande.html#s3_region
$endpoint = $configuration->getEndpoint();
$hostname = $bucket . '.' . $endpoint;
/**
* If there is no bucket we use the default endpoint, whatever it is. For Amazon S3 this format is only used
* when we are making account-level, cross-region requests, e.g. list all buckets. For S3-compatible APIs it
* depends on the API, but generally it's just for listing available buckets.
*/
if (empty($bucket)) {
return $endpoint;
}
/**
* If a custom endpoint has been specified we have to use the v2 signature API and its old-style hostnames, i.e.
* "virtual hosting". For example with an endpoint s3.example.com and bucket foobar the hostname would be
* foobar.s3.example.com
*/
if ($endpoint != 's3.amazonaws.com') {
return $hostname;
}
/**
* If we are using Amazon S3 with v2 signatures we have to use virual hosting (old-style) hostnames. So, a
* bucket called foobar needs to be accessed through the hostname foobar.s3.amazonaws.com
*/
if ($configuration->getSignatureMethod() != 'v4') {
return $hostname;
}
/**
* If we are not asked to use legacy path style access return the virtual hosting style hostname
*/
if (!$configuration->getUseLegacyPathStyle()) {
return $hostname;
}
/**
* When using the Amazon S3 with the v4 signature API we have to use a different hostname per region. The
* mapping can be found in http://docs.aws.amazon.com/general/latest/gr/rande.html#s3_region and boils down to
* the replacing s3.amazonaws.com with s3-REGION.amazonaws.com The only exception is the old, very first S3
* region us-east-1 whose regional hostname is s3-external-1.amazonaws.com just to make our life harder...
*/
$region = $configuration->getRegion();
if ($region == 'us-east-1') {
$region = 'external-1';
}
return str_replace('s3', 's3-' . $region, $endpoint);
}
