README.md

Config hashing

Small Node.js module that allows creating a hash from a config object.

This module uses Node.js built-in crypto module to access the sha256 hashing algorithm. A similar functionality can be achieved in the browser environment using the SubtleCrypto API. Open an issue if you need this functionality in browser.

Usage

1. Call serializePlainObject to uniquely serialize a config file. This functions recursively sorts the properties of an object, such that {a: 1, b: 2} and {b: 2, a: 1} will produce the same result.
2. Call createSha256Hash to create a hash from the serialized object.

const serializedConfig = serializePlainObject(config);
const hash = createSha256Hash(serializedConfig);

To simulate the same behavior in UNIX shell, you can use the following command:

# Assumes jq, tr, sha256sum and awk are available
jq --sort-keys --compact-output . ./file.json | tr -d '\n' | sha256sum | awk '{ print "0x"$1 }'