How is the Docker image digest calculated?

Question

The digest is a hash file sha256 of the docker image, but the image is not one file, but a set of layers. I assumed that the digest was a sha256 hash over the image manifest file, but I calculated the sha256 hash file from numerous manifest files and compared the result with the docker-digest providing the image, and they are diff. So what exactly is the sha256 hash for creating an Image digest value?

Answer 1

Based on my adventures in the Docker source, it seems that the digest is a SHA256 (default) JSON string that represents the image configuration.

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Answer 2

Image Digest - . , , caclutae .

https://docs.docker.com/registry/spec/api/#content-digests

HEADER DIGEST

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