BookStack Code Mirror - bookstack/blob - app/Exports/ZipExportFiles.php

   1 <?php
   2
   3 namespace BookStack\Exports;
   4
   5 use BookStack\Uploads\Attachment;
   6 use BookStack\Uploads\AttachmentService;
   7 use Illuminate\Support\Str;
   8
   9 class ZipExportFiles
  10 {
  11     /**
  12      * References for attachments by attachment ID.
  13      * @var array<int, string>
  14      */
  15     protected array $attachmentRefsById = [];
  16
  17     public function __construct(
  18         protected AttachmentService $attachmentService,
  19     ) {
  20     }
  21
  22     /**
  23      * Gain a reference to the given attachment instance.
  24      * This is expected to be a file-based attachment that the user
  25      * has visibility of, no permission/access checks are performed here.
  26      */
  27     public function referenceForAttachment(Attachment $attachment): string
  28     {
  29         if (isset($this->attachmentRefsById[$attachment->id])) {
  30             return $this->attachmentRefsById[$attachment->id];
  31         }
  32
  33         do {
  34             $fileName = Str::random(20) . '.' . $attachment->extension;
  35         } while (in_array($fileName, $this->attachmentRefsById));
  36
  37         $this->attachmentRefsById[$attachment->id] = $fileName;
  38
  39         return $fileName;
  40     }
  41
  42     /**
  43      * Extract each of the ZIP export tracked files.
  44      * Calls the given callback for each tracked file, passing a temporary
  45      * file reference of the file contents, and the zip-local tracked reference.
  46      */
  47     public function extractEach(callable $callback): void
  48     {
  49         foreach ($this->attachmentRefsById as $attachmentId => $ref) {
  50             $attachment = Attachment::query()->find($attachmentId);
  51             $stream = $this->attachmentService->streamAttachmentFromStorage($attachment);
  52             $tmpFile = tempnam(sys_get_temp_dir(), 'bszipfile-');
  53             $tmpFileStream = fopen($tmpFile, 'w');
  54             stream_copy_to_stream($stream, $tmpFileStream);
  55             $callback($tmpFile, $ref);
  56         }
  57     }
  58 }