Update dependecies & change package name for self-hosting in tornado scope

.npmrc

@@ -0,0 +1 @@
+@tornado:registry=https://git.tornado.ws/api/packages/tornado-packages/npm/

package.json

@@ -1,8 +1,12 @@
 {
-  "name": "fixed-merkle-tree",
-  "version": "0.3.4",
+  "name": "@tornado/fixed-merkle-tree",
+  "version": "0.4.0",
   "description": "Fixed depth merkle tree implementation with sequential inserts",
   "main": "src/merkleTree.js",
+  "repository": {
+    "type": "git",
+    "url": "https://git.tornado.ws/tornado-packages/fixed-merkle-tree.git"
+  },
   "scripts": {
     "test": "mocha",
     "lint": "eslint ."
@@ -18,8 +22,8 @@
     "src/*"
   ],
   "dependencies": {
-    "snarkjs": "git+https://github.com/tornadocash/snarkjs.git#869181cfaf7526fe8972073d31655493a04326d5",
-    "circomlib": "git+https://github.com/tornadocash/circomlib.git#5beb6aee94923052faeecea40135d45b6ce6172c"
+    "@tornado/circomlib": "^0.0.21",
+    "@tornado/snarkjs": "^0.1.20"
   },
   "devDependencies": {
     "babel-eslint": "^10.1.0",

src/merkleTree.js

@@ -152,6 +152,36 @@ class MerkleTree {
   elements() {
     return this._layers[0].slice()
   }
+
+  /**
+   * Serialize entire tree state including intermediate layers into a plain object
+   * Deserializing it back will not require to recompute any hashes
+   * Elements are not converted to a plain type, this is responsibility of the caller
+   */
+  serialize() {
+    return {
+      levels: this.levels,
+      capacity: this.capacity,
+      zeroElement: this.zeroElement,
+      _zeros: this._zeros,
+      _layers: this._layers,
+    }
+  }
+
+  /**
+   * Deserialize data into a MerkleTree instance
+   * Make sure to provide the same hashFunction as was used in the source tree,
+   * otherwise the tree state will be invalid
+   *
+   * @param data
+   * @param hashFunction
+   * @returns {MerkleTree}
+   */
+  static deserialize(data, hashFunction) {
+    const instance = Object.assign(Object.create(this.prototype), data)
+    instance._hash = hashFunction || defaultHash
+    return instance
+  }
 }
 
 module.exports = MerkleTree

src/mimc.js

@@ -1,3 +1,4 @@
-const { mimcsponge } = require('circomlib')
-const { bigInt } = require('snarkjs')
-module.exports = (left, right) => mimcsponge.multiHash([bigInt(left), bigInt(right)]).toString()
+const { mimcsponge } = require("@tornado/circomlib");
+const { bigInt } = require("@tornado/snarkjs");
+module.exports = (left, right) =>
+  mimcsponge.multiHash([bigInt(left), bigInt(right)]).toString();

test/merkleTree.test.js

@@ -202,4 +202,19 @@ describe('MerkleTree', () => {
       ])
     })
   })
+
+  describe('#serialize', () => {
+    it('should work', () => {
+      const src = new MerkleTree(10, [1, 2, 3])
+      const data = src.serialize()
+      const dst = MerkleTree.deserialize(data)
+
+      src.root().should.equal(dst.root())
+
+      src.insert(10)
+      dst.insert(10)
+
+      src.root().should.equal(dst.root())
+    })
+  })
 })