416 range error

[mtrezza]

Issue

I see a significant amount of 416 Range Not Satisfiable logs with our CDN. These errors only occur in the iOS app with Nuke, not in the Android app with Glide, which is loading the same images. However, I have not seen any issues with image loading in the app and there are no user complaints about images not loading.

Logs

Status	Timestamp	Remote IP	Size	Path
416	2020-07-31 01:55:42	(REDACTED)	598 Bytes	(REDACTED)

The "size" in the logs which I assume is the requested range is always around 400 - 600 Bytes for these 416 errors.
For successful CDN responses, "size" is the actual image size, like several KB.

Question

Are there any cases in which Nuke uses range requests?

[kean]

Hi, yes, by default Nuke uses range requests and this error code is most likely related to them. To disable it, you can set isResumableDataEnabled to false on the pipeline configuration. However, it would be great to investigate and try to fix it.

[kean]

Nuke has a very simple algorithm for setting requested ranges, I'm not sure what can be wrong with the range.

[kean]

Hey, @mtrezza. Any updates on this one?

[mtrezza]

Unfortunately not. Our CDN provider does not log the specific ranges that produce these 416 errors. We will have to implement a log client side in Nuke, but not sure how to do this in a quick way other than forking Nuke.

[cjmconie]

Hi, I am experiencing a similar issue.

It seems to appear when there are concurrent requests, for example inside a UICollectionView displaying a grid of UICollectionViewCells each having a UIImageView . I'm using Nuke.loadImage(with:into:). ImagePipeline is unmodified. Images are being requested directly from Firebase Storage. The error from Nuke is: Failed to load image data: Response status code was unacceptable: 416

Customising the ImagePipeline by setting isResumableDataEnabled as false resolves the issue.

Nuke 9.1.1 | Xcode 11.7 | Swift 5.2.4

Is there any more information I can provide to help?

[mattczech]

Hello, I'm also seeing occasional 416 errors.

In my case, I'm loading images stored in S3. Each 416 that I've observed is a result of Nuke requesting a starting byte count that is equal to the size of the image.

I'm using a UICollectionView to display a grid of images with Nuke.loadImage(with:into:). No modifications to the pipeline.

When I've seen the error, I've observed the following:

• The image exists in the URLCache and it's not expired.
• The collection view's initial layout occurs, cells are configured and images start loading. During this, one of the cells starts loading a different image.
• This cancels the original request while it's loading from the cache. It looks like the received data is then saved to ResumableData. The next time this image is loaded, it attempts to resume that request but since the full image data was saved as resumable data, it sends a range header with the starting offset equal to the size of the image, which is one byte past the last byte in the image.

Nuke 9.1.2

[mtrezza]

Well researched! That looks like a bug, if that is really the case.

[kean]

Hi, @mattczech. Thank you for providing this info. I went through the code and it does seem to be the case that the situation you are describing is possible. I'm going to address this issue in the upcoming release.

[kean]

I opened a PR with a fix https://github.com/kean/Nuke/pull/402/files