remove tiny-secp256k1 from xpub-lib dependencies, add initEccLib function, require for taproot

Author: turkycat

packages/xpub-cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@swan-bitcoin/xpub-cli",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "description": "Command-line wrapper around @swan-bitcoin/xpub-lib",
   "keywords": [
     "bitcoin",
@@ -53,8 +53,9 @@
     "test": "echo \"Warning: no test specified\""
   },
   "dependencies": {
-    "@swan-bitcoin/xpub-lib": "^0.2.0",
-    "commander": "^6.1.0"
+    "@swan-bitcoin/xpub-lib": "^0.2.1",
+    "commander": "^6.1.0",
+    "tiny-secp256k1": "^2.2.3"
   },
   "devDependencies": {
     "@babel/cli": "^7.11.6",

packages/xpub-cli/src/xpub.js

@@ -2,12 +2,14 @@
 
 const {
   Network,
+  initEccLib,
   isValidAddress,
   isValidExtPubKey,
   addressFromExtPubKey,
   addressesFromExtPubKey,
   Purpose,
 } = require("@swan-bitcoin/xpub-lib")
+import * as ecc from 'tiny-secp256k1'
 const { version } = require("../package.json")
 
 function parsePurpose(purpose) {
@@ -72,6 +74,8 @@ program
       cmdObj.help()
     }
 
+    initEccLib(ecc)
+
     const network = cmdObj.testnet ? Network.TESTNET : Network.MAINNET
     if (!isValidExtPubKey(extPubKey, network)) {
       console.error(`error: invalid extended public key '${extPubKey}'`)

packages/xpub-lib/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@swan-bitcoin/xpub-lib",
-  "version": "0.2.0",
+  "version": "0.2.1",
   "description": "A JavaScript library for bitcoin address derivation from extended public keys, built upon bitcoinjs-lib and Unchained's bitcoin utilities. Supports P2PKH, P2SH, and P2WPKH (bech32) addresses as defined in BIP44, BIP49, and BIP84.",
   "author": "Pablof7z <pablo@swan.com>",
   "license": "MIT",
@@ -34,8 +34,7 @@
   ],
   "dependencies": {
     "@caravan/bitcoin": "^0.3.1",
-    "bitcoinjs-lib": "^6.1.7",
-    "tiny-secp256k1": "^2.2.3"
+    "bitcoinjs-lib": "^6.1.7"
   },
   "scripts": {
     "babel-version": "babel --version",

packages/xpub-lib/src/derivation.js

@@ -5,7 +5,6 @@
  */
 
 import * as bitcoin from "bitcoinjs-lib"
-import * as ecc from 'tiny-secp256k1';
 import { toXOnly } from 'bitcoinjs-lib/src/psbt/bip371';
 import { deriveChildPublicKey, networkData, Network } from "@caravan/bitcoin"
 import { fullDerivationPath, partialKeyDerivationPath } from "./paths"
@@ -35,7 +34,20 @@ const DEFAULT_NETWORK = Network.TESTNET
  * */
 const DEFAULT_PURPOSE = Purpose.P2WPKH
 
-bitcoin.initEccLib(ecc);
+/**
+ * The secp256k1 interface to use for Taproot address derivation.
+ */
+let eccInstance = null;
+
+/**
+ * Initialize the ECC library for Taproot address derivation.
+ *
+ * @param {object} eccLib - The secp256k1 interface to use.
+ */
+function initEccLib(eccLib) {
+  eccInstance = eccLib;
+  bitcoin.initEccLib(eccInstance);
+}
 
 /**
  * Derive a single address from a public key.
@@ -73,7 +85,9 @@ function deriveAddress({ purpose, pubkey, network }) {
       return bc1qAddress
     }
     case Purpose.P2TR: {
-      // Context: https://bitcoinops.org/en/topics/x-only-public-keys/
+      if (!eccInstance) {
+        throw new Error("An instance of an ECC library implementing the secp256k1 curve must be initialized to generate taproot addresses. You must call initEccLib() first.");
+      }
       const xOnlyPubkey = toXOnly(pubkey)
       const { address: bc1pAddress } = bitcoin.payments.p2tr({
         internalPubkey:  xOnlyPubkey,
@@ -176,4 +190,4 @@ function addressesFromExtPubKey({
   return addresses
 }
 
-export { addressFromExtPubKey, addressesFromExtPubKey }
+export { addressFromExtPubKey, addressesFromExtPubKey, initEccLib }