What would be the most elegant way to decrypt image data before it is sent to the pipeline? about nuke HOT 4 OPEN

The decoding happens using ImageDecoding objects. I suggest adding the decryption step during that stage, and then invoking the built-in decoders. See https://kean-docs.github.io/nuke/documentation/nuke/image-decoding for more information.

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Ah, that sounds promising!

Thanks for making such a great library. It is amazing!

Edit: I can use the userInfo dictionary for the key I suppose!

ImagePipeline.shared = ImagePipeline {
   $0.makeImageDecoder = { context in
      if let key = context.request.userInfo["key"] as? Data {
         var copy = context
         copy.data = try! decrypt(data: context.data, using: key)
         return ImageDecoderRegistry.shared.decoder(for: copy)
      }
      return ImageDecoderRegistry.shared.decoder(for: context)
   }
}

When creating the image pipeline, I set the makeImageDecoder closure to check for a given key and then decode the data. The data is properly decoded, but the image state says Failed to decode image data using decoder Nuke.ImageDecoders.Default even though I can check with the debugger that the default decoder can in fact decode the image.

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Failed to decode image data using decoder Nuke.ImageDecoders.Default even though I can check with the debugger that the default decoder can in fact decode the image.

The code that you provided looks good.

Btw, makeImageDecoder is called on the pipeline's background queue, so I think it's an OK trade-off performance-wise to put it there.

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Sorry for the very late responses here.

So It seems Nuke doesn't get me the correct decoder with my code. If I add a debug line (the one after the comment)

$0.makeImageDecoder = { context in
    if let key = context.request.userInfo["key"] as? Data {
        var copy = context
        copy.data = try! Cryptor.default.decrypt(data: context.data, using: .init(data: key))
        // this gets me to the correct image…
        let image = try! Nuke.ImageDecoders.Default().decode(copy.data)
        return ImageDecoderRegistry.shared.decoder(for: copy)
    }
    return ImageDecoderRegistry.shared.decoder(for: context)
}

then I can see that the image is correctly decoded. returning the ImageDecoderRegistry.shared.decoder(for: copy) though doesn't seem to work (although the error message that I receive
Failed to decode image data using decoder Nuke.ImageDecoders.Default
seems to indicate it wants to pick the right one anyway.

Do you have any suggestions of where I should be looking?

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