SDWebImageView Cache issue when offline and with percent escaped URLs

Question

I am using SDWebImage to display images asynchronously, and cache them, then to get them when in offline mode.

I am having an issue with SDWebImageDownloader and UIImageView+WebCache Cache when using offline mode, and that issue appears only when dealing with percent escaped URLs, that have some special characters like '{'.

In online mode all works fine, but in offline mode the images with URLs containing percent escapes are not loaded

[myImageView setImageWithURL:[urlImage percentEscapedURL]
                   completed:^(UIImage *image, NSError *error, SDImageCacheType cacheType) {
                       //image here is loaded in offline mode only if its URL does not need percent escapes
                   }];

The same issue with SDWebImageDownloader.

I tried to debug SDImageView behaviour, and it seems that it's using the iOS SDK NSCachedURLResponse behaviour.

I am testing with https://github.com/rs/SDWebImage/ with iOS 7.0

Any one has got the same issue? any workaround?

Answer 1

SDWebImage has some property declared in SDWebImageManager.h:

@property (strong) NSString *(^cacheKeyFilter)(NSURL *url);

There are the description of this property from corresponding file:

/**
 * The cache filter is a block used each time SDWebImageManager need to convert an URL into a cache key. This can
 * be used to remove dynamic part of an image URL.
 *
 * The following example sets a filter in the application delegate that will remove any query-string from the
 * URL before to use it as a cache key:
 *
 * @code

[[SDWebImageManager sharedManager] setCacheKeyFilter:^(NSURL *url) {
    url = [[NSURL alloc] initWithScheme:url.scheme host:url.host path:url.path];
    return [url absoluteString];
}];

 * @endcode
 */

I think you can try to do some changes in corresponding code.