Merge pull request aws#763 from jeskew/fix/filesize-agnostic-copy-abs…

…traction

Add a multipart copy abstraction

src/Multipart/AbstractUploadManager.php

@@ -0,0 +1,297 @@
+<?php
+namespace Aws\Multipart;
+
+use Aws\AwsClientInterface as Client;
+use Aws\CommandInterface;
+use Aws\CommandPool;
+use Aws\Exception\AwsException;
+use Aws\Exception\MultipartUploadException;
+use Aws\Result;
+use Aws\ResultInterface;
+use GuzzleHttp\Promise;
+use GuzzleHttp\Promise\PromiseInterface;
+use GuzzleHttp\Psr7;
+use InvalidArgumentException as IAE;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Encapsulates the execution of a multipart upload to S3 or Glacier.
+ *
+ * @internal
+ */
+abstract class AbstractUploadManager implements Promise\PromisorInterface
+{
+    const DEFAULT_CONCURRENCY = 5;
+
+    /** @var array Default values for base multipart configuration */
+    private static $defaultConfig = [
+        'part_size'       => null,
+        'state'           => null,
+        'concurrency'     => self::DEFAULT_CONCURRENCY,
+        'before_initiate' => null,
+        'before_upload'   => null,
+        'before_complete' => null,
+    ];
+
+    /** @var Client Client used for the upload. */
+    protected $client;
+
+    /** @var array Configuration used to perform the upload. */
+    protected $config;
+
+    /** @var array Service-specific information about the upload workflow. */
+    protected $info;
+
+    /** @var PromiseInterface Promise that represents the multipart upload. */
+    protected $promise;
+
+    /** @var UploadState State used to manage the upload. */
+    protected $state;
+
+    /**
+     * @param Client $client
+     * @param array  $config
+     */
+    public function __construct(Client $client, array $config = [])
+    {
+        $this->client = $client;
+        $this->info = $this->loadUploadWorkflowInfo();
+        $this->config = $config + self::$defaultConfig;
+        $this->state = $this->determineState();
+    }
+
+    /**
+     * Returns the current state of the upload
+     *
+     * @return UploadState
+     */
+    public function getState()
+    {
+        return $this->state;
+    }
+
+    /**
+     * Upload the source using multipart upload operations.
+     *
+     * @return Result The result of the CompleteMultipartUpload operation.
+     * @throws \LogicException if the upload is already complete or aborted.
+     * @throws MultipartUploadException if an upload operation fails.
+     */
+    public function upload()
+    {
+        return $this->promise()->wait();
+    }
+
+    /**
+     * Upload the source asynchronously using multipart upload operations.
+     *
+     * @return PromiseInterface
+     */
+    public function promise()
+    {
+        if ($this->promise) {
+            return $this->promise;
+        }
+
+        return $this->promise = Promise\coroutine(function () {
+            // Initiate the upload.
+            if ($this->state->isCompleted()) {
+                throw new \LogicException('This multipart upload has already '
+                    . 'been completed or aborted.'
+                );
+            } elseif (!$this->state->isInitiated()) {
+                $result = (yield $this->execCommand('initiate', $this->getInitiateParams()));
+                $this->state->setUploadId(
+                    $this->info['id']['upload_id'],
+                    $result[$this->info['id']['upload_id']]
+                );
+                $this->state->setStatus(UploadState::INITIATED);
+            }
+
+            // Create a command pool from a generator that yields UploadPart
+            // commands for each upload part.
+            $resultHandler = $this->getResultHandler($errors);
+            $commands = new CommandPool(
+                $this->client,
+                $this->getUploadCommands($resultHandler),
+                [
+                    'concurrency' => $this->config['concurrency'],
+                    'before'      => $this->config['before_upload'],
+                ]
+            );
+
+            // Execute the pool of commands concurrently, and process errors.
+            yield $commands->promise();
+            if ($errors) {
+                throw new MultipartUploadException($this->state, $errors);
+            }
+
+            // Complete the multipart upload.
+            yield $this->execCommand('complete', $this->getCompleteParams());
+            $this->state->setStatus(UploadState::COMPLETED);
+        })->otherwise(function (\Exception $e) {
+            // Throw errors from the operations as a specific Multipart error.
+            if ($e instanceof AwsException) {
+                $e = new MultipartUploadException($this->state, $e);
+            }
+            throw $e;
+        });
+    }
+
+    protected function getConfig()
+    {
+        return $this->config;
+    }
+
+    /**
+     * Provides service-specific information about the multipart upload
+     * workflow.
+     *
+     * This array of data should include the keys: 'command', 'id', and 'part_num'.
+     *
+     * @return array
+     */
+    abstract protected function loadUploadWorkflowInfo();
+
+    /**
+     * Determines the part size to use for upload parts.
+     *
+     * Examines the provided partSize value and the source to determine the
+     * best possible part size.
+     *
+     * @throws \InvalidArgumentException if the part size is invalid.
+     *
+     * @return int
+     */
+    abstract protected function determinePartSize();
+
+    /**
+     * Uses information from the Command and Result to determine which part was
+     * uploaded and mark it as uploaded in the upload's state.
+     *
+     * @param CommandInterface $command
+     * @param ResultInterface  $result
+     */
+    abstract protected function handleResult(
+        CommandInterface $command,
+        ResultInterface $result
+    );
+
+    /**
+     * Gets the service-specific parameters used to initiate the upload.
+     *
+     * @return array
+     */
+    abstract protected function getInitiateParams();
+
+    /**
+     * Gets the service-specific parameters used to complete the upload.
+     *
+     * @return array
+     */
+    abstract protected function getCompleteParams();
+
+    /**
+     * Based on the config and service-specific workflow info, creates a
+     * `Promise` for an `UploadState` object.
+     *
+     * @return PromiseInterface A `Promise` that resolves to an `UploadState`.
+     */
+    private function determineState()
+    {
+        // If the state was provided via config, then just use it.
+        if ($this->config['state'] instanceof UploadState) {
+            return $this->config['state'];
+        }
+
+        // Otherwise, construct a new state from the provided identifiers.
+        $required = $this->info['id'];
+        $id = [$required['upload_id'] => null];
+        unset($required['upload_id']);
+        foreach ($required as $key => $param) {
+            if (!$this->config[$key]) {
+                throw new IAE('You must provide a value for "' . $key . '" in '
+                    . 'your config for the MultipartUploader for '
+                    . $this->client->getApi()->getServiceFullName() . '.');
+            }
+            $id[$param] = $this->config[$key];
+        }
+        $state = new UploadState($id);
+        $state->setPartSize($this->determinePartSize());
+
+        return $state;
+    }
+
+    /**
+     * Executes a MUP command with all of the parameters for the operation.
+     *
+     * @param string $operation Name of the operation.
+     * @param array  $params    Service-specific params for the operation.
+     *
+     * @return PromiseInterface
+     */
+    private function execCommand($operation, array $params)
+    {
+        // Create the command.
+        $command = $this->client->getCommand(
+            $this->info['command'][$operation],
+            $params + $this->state->getId()
+        );
+
+        // Execute the before callback.
+        if (is_callable($this->config["before_{$operation}"])) {
+            $this->config["before_{$operation}"]($command);
+        }
+
+        // Execute the command asynchronously and return the promise.
+        return $this->client->executeAsync($command);
+    }
+
+    /**
+     * Returns a middleware for processing responses of part upload operations.
+     *
+     * - Adds an onFulfilled callback that calls the service-specific
+     *   handleResult method on the Result of the operation.
+     * - Adds an onRejected callback that adds the error to an array of errors.
+     * - Has a passedByRef $errors arg that the exceptions get added to. The
+     *   caller should use that &$errors array to do error handling.
+     *
+     * @param array $errors Errors from upload operations are added to this.
+     *
+     * @return callable
+     */
+    private function getResultHandler(&$errors = [])
+    {
+        return function (callable $handler) use (&$errors) {
+            return function (
+                CommandInterface $command,
+                RequestInterface $request = null
+            ) use ($handler, &$errors) {
+                return $handler($command, $request)->then(
+                    function (ResultInterface $result) use ($command) {
+                        $this->handleResult($command, $result);
+                        return $result;
+                    },
+                    function (AwsException $e) use (&$errors) {
+                        $errors[$e->getCommand()[$this->info['part_num']]] = $e;
+                        return new Result();
+                    }
+                );
+            };
+        };
+    }
+
+    /**
+     * Creates a generator that yields part data for the upload's source.
+     *
+     * Yields associative arrays of parameters that are ultimately merged in
+     * with others to form the complete parameters of a  command. This can
+     * include the Body parameter, which is a limited stream (i.e., a Stream
+     * object, decorated with a LimitStream).
+     *
+     * @param callable $resultHandler
+     *
+     * @return \Generator
+     */
+    abstract protected function getUploadCommands(callable $resultHandler);
+}