1: <?php
 2: /**
 3:  * Copyright 2012-2014 Rackspace US, Inc.
 4:  *
 5:  * Licensed under the Apache License, Version 2.0 (the "License");
 6:  * you may not use this file except in compliance with the License.
 7:  * You may obtain a copy of the License at
 8:  *
 9:  * http://www.apache.org/licenses/LICENSE-2.0
10:  *
11:  * Unless required by applicable law or agreed to in writing, software
12:  * distributed under the License is distributed on an "AS IS" BASIS,
13:  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14:  * See the License for the specific language governing permissions and
15:  * limitations under the License.
16:  */
17: 
18: namespace OpenCloud\ObjectStore\Upload;
19: 
20: use Guzzle\Http\EntityBody;
21: use Guzzle\Http\ReadLimitEntityBody;
22: 
23: /**
24:  * A transfer type which executes in a concurrent fashion, i.e. with multiple workers uploading at once. Each worker is
25:  * charged with uploading a particular chunk of data. The entity body is fragmented into n pieces - calculated by
26:  * dividing the total size by the individual part size.
27:  *
28:  * @codeCoverageIgnore
29:  */
30: class ConcurrentTransfer extends AbstractTransfer
31: {
32:     public function transfer()
33:     {
34:         $totalParts = (int) ceil($this->entityBody->getContentLength() / $this->partSize);
35:         $workers = min($totalParts, $this->options['concurrency']);
36:         $parts = $this->collectParts($workers);
37: 
38:         while ($this->transferState->count() < $totalParts) {
39: 
40:             $completedParts = $this->transferState->count();
41:             $requests = array();
42: 
43:             // Iterate over number of workers until total completed parts is what we need it to be
44:             for ($i = 0; $i < $workers && ($completedParts + $i) < $totalParts; $i++) {
45: 
46:                 // Offset is the current pointer multiplied by the standard chunk length
47:                 $offset = ($completedParts + $i) * $this->partSize;
48:                 $parts[$i]->setOffset($offset);
49: 
50:                 // If this segment is empty (i.e. buffering a half-full chunk), break the iteration
51:                 if ($parts[$i]->getContentLength() == 0) {
52:                     break;
53:                 }
54: 
55:                 // Add this to the request queue for later processing
56:                 $requests[] = TransferPart::createRequest(
57:                     $parts[$i],
58:                     $this->transferState->count() + $i + 1,
59:                     $this->client,
60:                     $this->options
61:                 );
62:             }
63: 
64:             // Iterate over our queued requests and process them
65:             foreach ($this->client->send($requests) as $response) {
66:                 // Add this part to the TransferState
67:                 $this->transferState->addPart(TransferPart::fromResponse($response));
68:             }
69:         }
70:     }
71: 
72:     /**
73:      * Partitions the entity body into an array - each worker is represented by a key, and the value is a
74:      * ReadLimitEntityBody object, whose read limit is fixed based on this object's partSize value. This will always
75:      * ensure the chunks are sent correctly.
76:      *
77:      * @param int    The total number of workers
78:      * @return array The worker array
79:      */
80:     private function collectParts($workers)
81:     {
82:         $uri = $this->entityBody->getUri();
83: 
84:         $array = array(new ReadLimitEntityBody($this->entityBody, $this->partSize));
85: 
86:         for ($i = 1; $i < $workers; $i++) {
87:             // Need to create a fresh EntityBody, otherwise you'll get weird 408 responses
88:             $array[] = new ReadLimitEntityBody(new EntityBody(fopen($uri, 'r')), $this->partSize);
89:         }
90: 
91:         return $array;
92:     }
93: }
94: