A Node implementation of MuHash algorithm, Ported from Bitcoin source code. The package is developed based on node-addon-api, and the core algorithm of MuHash is implemented in C++.
As stated in the Bitcoin source code, MuHash is a hashing algorithm that supports adding set elements in any order but also deleting in any order. As a result, it can maintain a running sum for a set of data as a whole, and add/remove when data is added to or removed from it.
The paper that proposed the algorithm is A New Paradigm for Collision-free Hashing: Incrementality at Reduced Cost (https://cseweb.ucsd.edu/~mihir/papers/inchash.pdf).
You can install directly using npm:
npm install muhash
If you want to download and compile it, follow the steps below:
git clone https://github.com/JezaChen/muhash-node.git
cd muhash-node
npm install
A complete example is given below, which covers all the usage of the package.
const MuHash = require('muhash').MuHash;
//Definition and initialization， the parameter must be of Buffer type
let muhash = new MuHash(Buffer.from("Test 1"));
//MuHash supports the insertion of elements, the parameter must be of Buffer type
muhash.insert(Buffer.from("Test 2"));
console.log(muhash.finalizeBase64()); //H("Test1", "Test2")
let muhash_1 = new MuHash(Buffer.from("Test 1"));
let muhash_2 = new MuHash(Buffer.from("Test 2"));
muhash_1.mul(muhash_2); //H("Test1") * H("Test2")
console.log(muhash_1.finalizeBase64()); //It can be discovered that H("Test1", "Test2") is equal to H("Test1") * H("Test2")
//Note that MuHash can no longer be used after calling FinalizeBase64 or FinalizeBuffer!
muhash_1 = new MuHash(Buffer.from("Test 1"));
muhash_2 = new MuHash(Buffer.from("Test 2"));
muhash_1.mul(muhash_2);
muhash_1.div(muhash_2); //muhash1 is H("Test1") * H("Test2") / H("Test2")
let muhash_3 = new MuHash(Buffer.from("Test 1"));
muhash_3.insert(Buffer.from("Test 2")); //Currently, muhash_3 is H("Test1", "Test 2")
muhash_3.remove(Buffer.from("Test 2")); //Now muhash_3 is H("Test1")
//It can be discovered that muhash_1 is euqal to muhash_3
console.log(muhash_1.finalizeBuffer());
console.log(muhash_3.finalizeBuffer());