<?php
namespace Aws\S3;
use Aws\AwsClientInterface;
use Aws\S3\Exception\DeleteMultipleObjectsException;
use GuzzleHttp\Promise;
use GuzzleHttp\Promise\PromisorInterface;
use GuzzleHttp\Promise\PromiseInterface;
/**
* Efficiently deletes many objects from a single Amazon S3 bucket using an
* iterator that yields keys. Deletes are made using the DeleteObjects API
* operation.
*
* $s3 = new Aws\S3\Client([
* 'region' => 'us-west-2',
* 'version' => 'latest'
* ]);
*
* $listObjectsParams = ['Bucket' => 'foo', 'Prefix' => 'starts/with/'];
* $delete = Aws\S3\BatchDelete::fromListObjects($s3, $listObjectsParams);
* // Asynchronously delete
* $promise = $delete->promise();
* // Force synchronous completion
* $delete->delete();
*
* When using one of the batch delete creational static methods, you can supply
* an associative array of options:
*
* - before: Function invoked before executing a command. The function is
* passed the command that is about to be executed. This can be useful
* for logging, adding custom request headers, etc.
* - batch_size: The size of each delete batch. Defaults to 1000.
*
* @link http://docs.aws.amazon.com/AmazonS3/latest/API/multiobjectdeleteapi.html
*/
class BatchDelete implements PromisorInterface
{
private $bucket;
/** @var AwsClientInterface */
private $client;
/** @var callable */
private $before;
/** @var PromiseInterface */
private $cachedPromise;
/** @var callable */
private $promiseCreator;
private $batchSize = 1000;
private $queue = [];
/**
* Creates a BatchDelete object from all of the paginated results of a
* ListObjects operation. Each result that is returned by the ListObjects
* operation will be deleted.
*
* @param AwsClientInterface $client AWS Client to use.
* @param array $listObjectsParams ListObjects API parameters
* @param array $options BatchDelete options.
*
* @return BatchDelete
*/
public static function fromListObjects(
AwsClientInterface $client,
array $listObjectsParams,
array $options = []
) {
$iter = $client->getPaginator('ListObjects', $listObjectsParams);
$bucket = $listObjectsParams['Bucket'];
$fn = function (BatchDelete $that) use ($iter) {
return $iter->each(function ($result) use ($that) {
$promises = [];
if (is_array($result['Contents'])) {
foreach ($result['Contents'] as $object) {
if ($promise = $that->enqueue($object)) {
$promises[] = $promise;
}
}
}
return $promises ? Promise\all($promises) : null;
});
};
return new self($client, $bucket, $fn, $options);
}
/**
* Creates a BatchDelete object from an iterator that yields results.
*
* @param AwsClientInterface $client AWS Client to use to execute commands
* @param string $bucket Bucket where the objects are stored
* @param \Iterator $iter Iterator that yields assoc arrays
* @param array $options BatchDelete options
*
* @return BatchDelete
*/
public static function fromIterator(
AwsClientInterface $client,
$bucket,
\Iterator $iter,
array $options = []
) {
$fn = function (BatchDelete $that) use ($iter) {
return Promise\coroutine(function () use ($that, $iter) {
foreach ($iter as $obj) {
if ($promise = $that->enqueue($obj)) {
yield $promise;
}
}
});
};
return new self($client, $bucket, $fn, $options);
}
public function promise()
{
if (!$this->cachedPromise) {
$this->cachedPromise = $this->createPromise();
}
return $this->cachedPromise;
}
/**
* Synchronously deletes all of the objects.
*
* @throws DeleteMultipleObjectsException on error.
*/
public function delete()
{
$this->promise()->wait();
}
/**
* @param AwsClientInterface $client Client used to transfer the requests
* @param string $bucket Bucket to delete from.
* @param callable $promiseFn Creates a promise.
* @param array $options Hash of options used with the batch
*
* @throws \InvalidArgumentException if the provided batch_size is <= 0
*/
private function __construct(
AwsClientInterface $client,
$bucket,
callable $promiseFn,
array $options = []
) {
$this->client = $client;
$this->bucket = $bucket;
$this->promiseCreator = $promiseFn;
if (isset($options['before'])) {
if (!is_callable($options['before'])) {
throw new \InvalidArgumentException('before must be callable');
}
$this->before = $options['before'];
}
if (isset($options['batch_size'])) {
if ($options['batch_size'] <= 0) {
throw new \InvalidArgumentException('batch_size is not > 0');
}
$this->batchSize = min($options['batch_size'], 1000);
}
}
private function enqueue(array $obj)
{
$this->queue[] = $obj;
return count($this->queue) >= $this->batchSize
? $this->flushQueue()
: null;
}
private function flushQueue()
{
static $validKeys = ['Key' => true, 'VersionId' => true];
if (count($this->queue) === 0) {
return null;
}
$batch = [];
while ($obj = array_shift($this->queue)) {
$batch[] = array_intersect_key($obj, $validKeys);
}
$command = $this->client->getCommand('DeleteObjects', [
'Bucket' => $this->bucket,
'Delete' => ['Objects' => $batch]
]);
if ($this->before) {
call_user_func($this->before, $command);
}
return $this->client->executeAsync($command)
->then(function ($result) {
if (!empty($result['Errors'])) {
throw new DeleteMultipleObjectsException(
$result['Deleted'] ?: [],
$result['Errors']
);
}
return $result;
});
}
/**
* Returns a promise that will clean up any references when it completes.
*
* @return PromiseInterface
*/
private function createPromise()
{
// Create the promise
$promise = call_user_func($this->promiseCreator, $this);
$this->promiseCreator = null;
// Cleans up the promise state and references.
$cleanup = function () {
$this->before = $this->client = $this->queue = null;
};
// When done, ensure cleanup and that any remaining are processed.
return $promise->then(
function () use ($cleanup) {
return Promise\promise_for($this->flushQueue())
->then($cleanup);
},
function ($reason) use ($cleanup) {
$cleanup();
return Promise\rejection_for($reason);
}
);
}
}