private function getChecksumsMiddleware()
{
return function (callable $handler) {
return function (CommandInterface $command, RequestInterface $request = null) use($handler) {
// Accept "ContentSHA256" with a lowercase "c" to match other Glacier params.
if (!$command['ContentSHA256'] && $command['contentSHA256']) {
$command['ContentSHA256'] = $command['contentSHA256'];
unset($command['contentSHA256']);
}
// If uploading, then make sure checksums are added.
$name = $command->getName();
if (($name === 'UploadArchive' || $name === 'UploadMultipartPart') && (!$command['checksum'] || !$command['ContentSHA256'])) {
$body = $request->getBody();
if (!$body->isSeekable()) {
throw new CouldNotCreateChecksumException('sha256');
}
// Add a tree hash if not provided.
if (!$command['checksum']) {
$body = new HashingStream($body, new TreeHash(), function ($result) use($command, &$request) {
$request = $request->withHeader('x-amz-sha256-tree-hash', bin2hex($result));
});
}
// Add a linear content hash if not provided.
if (!$command['ContentSHA256']) {
$body = new HashingStream($body, new PhpHash('sha256'), function ($result) use($command) {
$command['ContentSHA256'] = bin2hex($result);
});
}
// Read the stream in order to calculate the hashes.
while (!$body->eof()) {
$body->read(1048576);
}
$body->seek(0);
}
// Set the content hash header if a value is in the command.
if ($command['ContentSHA256']) {
$request = $request->withHeader('x-amz-content-sha256', $command['ContentSHA256']);
}
return $handler($command, $request);
};
};
}
