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mirror of https://github.com/BookStackApp/BookStack.git synced 2024-10-30 15:42:41 +01:00
BookStack/app/Uploads/ImageResizer.php
Dan Brown b2d48d9a7f
Images: Rolled out image memory handling to image actions
- Moved thumnbail loading out of repo into ImageResizer.
- Updated gallery and editor image handling to show errors where
  possible to indicate memory issues for resizing/thumbs.
- Updated gallery to load image data in a per-image basis via edit form
  for more resiliant thumb/data fetching. Data was previously provided
  via gallery listing, which could be affected by failing generation
  of other images.
- Updated image manager double click handling to be more pleasant and
  not flash away the edit form.
- Updated editor handlers to use main URL when thumbs fail to load.
2023-10-01 13:05:18 +01:00

207 lines
6.8 KiB
PHP

<?php
namespace BookStack\Uploads;
use BookStack\Exceptions\ImageUploadException;
use Exception;
use GuzzleHttp\Psr7\Utils;
use Illuminate\Support\Facades\Cache;
use Intervention\Image\Image as InterventionImage;
use Intervention\Image\ImageManager;
class ImageResizer
{
protected const THUMBNAIL_CACHE_TIME = 604_800; // 1 week
public function __construct(
protected ImageManager $intervention,
protected ImageStorage $storage,
) {
}
/**
* Load gallery thumbnails for a set of images.
* @param iterable<Image> $images
*/
public function loadGalleryThumbnailsForMany(iterable $images, bool $shouldCreate = false): void
{
foreach ($images as $image) {
$this->loadGalleryThumbnailsForImage($image, $shouldCreate);
}
}
/**
* Load gallery thumbnails into the given image instance.
*/
public function loadGalleryThumbnailsForImage(Image $image, bool $shouldCreate): void
{
$thumbs = ['gallery' => null, 'display' => null];
try {
$thumbs['gallery'] = $this->resizeToThumbnailUrl($image, 150, 150, false, $shouldCreate);
$thumbs['display'] = $this->resizeToThumbnailUrl($image, 1680, null, true, $shouldCreate);
} catch (Exception $exception) {
// Prevent thumbnail errors from stopping execution
}
$image->setAttribute('thumbs', $thumbs);
}
/**
* Get the thumbnail for an image.
* If $keepRatio is true only the width will be used.
* Checks the cache then storage to avoid creating / accessing the filesystem on every check.
*
* @throws Exception
*/
public function resizeToThumbnailUrl(
Image $image,
?int $width,
?int $height,
bool $keepRatio = false,
bool $shouldCreate = false
): ?string {
// Do not resize GIF images where we're not cropping
if ($keepRatio && $this->isGif($image)) {
return $this->storage->getPublicUrl($image->path);
}
$thumbDirName = '/' . ($keepRatio ? 'scaled-' : 'thumbs-') . $width . '-' . $height . '/';
$imagePath = $image->path;
$thumbFilePath = dirname($imagePath) . $thumbDirName . basename($imagePath);
$thumbCacheKey = 'images::' . $image->id . '::' . $thumbFilePath;
// Return path if in cache
$cachedThumbPath = Cache::get($thumbCacheKey);
if ($cachedThumbPath && !$shouldCreate) {
return $this->storage->getPublicUrl($cachedThumbPath);
}
// If thumbnail has already been generated, serve that and cache path
$disk = $this->storage->getDisk($image->type);
if (!$shouldCreate && $disk->exists($thumbFilePath)) {
Cache::put($thumbCacheKey, $thumbFilePath, static::THUMBNAIL_CACHE_TIME);
return $this->storage->getPublicUrl($thumbFilePath);
}
$imageData = $disk->get($imagePath);
// Do not resize apng images where we're not cropping
if ($keepRatio && $this->isApngData($image, $imageData)) {
Cache::put($thumbCacheKey, $image->path, static::THUMBNAIL_CACHE_TIME);
return $this->storage->getPublicUrl($image->path);
}
// If not in cache and thumbnail does not exist, generate thumb and cache path
$thumbData = $this->resizeImageData($imageData, $width, $height, $keepRatio);
$disk->put($thumbFilePath, $thumbData, true);
Cache::put($thumbCacheKey, $thumbFilePath, static::THUMBNAIL_CACHE_TIME);
return $this->storage->getPublicUrl($thumbFilePath);
}
/**
* Resize the image of given data to the specified size, and return the new image data.
*
* @throws ImageUploadException
*/
public function resizeImageData(string $imageData, ?int $width, ?int $height, bool $keepRatio): string
{
try {
$thumb = $this->intervention->make($imageData);
} catch (Exception $e) {
throw new ImageUploadException(trans('errors.cannot_create_thumbs'));
}
$this->orientImageToOriginalExif($thumb, $imageData);
if ($keepRatio) {
$thumb->resize($width, $height, function ($constraint) {
$constraint->aspectRatio();
$constraint->upsize();
});
} else {
$thumb->fit($width, $height);
}
$thumbData = (string) $thumb->encode();
// Use original image data if we're keeping the ratio
// and the resizing does not save any space.
if ($keepRatio && strlen($thumbData) > strlen($imageData)) {
return $imageData;
}
return $thumbData;
}
/**
* Orientate the given intervention image based upon the given original image data.
* Intervention does have an `orientate` method but the exif data it needs is lost before it
* can be used (At least when created using binary string data) so we need to do some
* implementation on our side to use the original image data.
* Bulk of logic taken from: https://github.com/Intervention/image/blob/b734a4988b2148e7d10364b0609978a88d277536/src/Intervention/Image/Commands/OrientateCommand.php
* Copyright (c) Oliver Vogel, MIT License.
*/
protected function orientImageToOriginalExif(InterventionImage $image, string $originalData): void
{
if (!extension_loaded('exif')) {
return;
}
$stream = Utils::streamFor($originalData)->detach();
$exif = @exif_read_data($stream);
$orientation = $exif ? ($exif['Orientation'] ?? null) : null;
switch ($orientation) {
case 2:
$image->flip();
break;
case 3:
$image->rotate(180);
break;
case 4:
$image->rotate(180)->flip();
break;
case 5:
$image->rotate(270)->flip();
break;
case 6:
$image->rotate(270);
break;
case 7:
$image->rotate(90)->flip();
break;
case 8:
$image->rotate(90);
break;
}
}
/**
* Checks if the image is a gif. Returns true if it is, else false.
*/
protected function isGif(Image $image): bool
{
return strtolower(pathinfo($image->path, PATHINFO_EXTENSION)) === 'gif';
}
/**
* Check if the given image and image data is apng.
*/
protected function isApngData(Image $image, string &$imageData): bool
{
$isPng = strtolower(pathinfo($image->path, PATHINFO_EXTENSION)) === 'png';
if (!$isPng) {
return false;
}
$initialHeader = substr($imageData, 0, strpos($imageData, 'IDAT'));
return str_contains($initialHeader, 'acTL');
}
}