Layer Cake

Challenge

Someone said there would be cake.

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hackyeaster/layercake:latest

Solution

Upon pulling the first layer was fat, the next 30 were small, so, guessing they’re just overwriting a file repeatedly.

So we immediately write this handy one liner, to search through every diff directory provided by docker, copying any egg.png files into tmp.

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for x in $(docker inspect hackyeaster/layercake:latest | jq '.[0].GraphDriver.Data.LowerDir' -r | tr ':' '\n'); do
	egg=$(sudo find $x -name egg.png); hash=$(echo $egg | cut -d/ -f 6); sudo cp $egg /tmp/egg-$hash.png;
done;

And then we see all of the eggs and rely on manual inspection to find our egg.

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