WIP: feat: (1.5 hour) send payment to multiple outputs from CSV

Author: AJ ONeal

bin/create-tx.js

@@ -0,0 +1,101 @@
+#!/usr/bin/env node
+"use strict";
+
+let Fs = require("fs").promises;
+
+let Dash = require("../lib/dash.js");
+let Insight = require("../lib/insight.js");
+
+async function main() {
+  let insightBaseUrl =
+    process.env.INSIGHT_BASE_URL || "https://insight.dash.org";
+  let insightApi = Insight.create({ baseUrl: insightBaseUrl });
+  let dashApi = Dash.create({ insightApi: insightApi });
+
+  let wiffilename = process.argv[2] || "";
+  if (!wiffilename) {
+    console.error(`Usage: pay ./source.wif ./targets.csv ./change.b58c`);
+    process.exit(1);
+    return;
+  }
+  let wif = await Fs.readFile(wiffilename, "utf8");
+  wif = wif.trim();
+
+  let payfilename = process.argv[3] || "";
+  if (!payfilename) {
+    console.error(`Usage: pay ./source.wif ./targets.csv ./change.b58c`);
+    process.exit(1);
+    return;
+  }
+  let paymentsCsv = await Fs.readFile(payfilename, "utf8");
+  paymentsCsv = paymentsCsv.trim();
+  /** @type {Array<{ address: String, satoshis: Number }>} */
+  //@ts-ignore
+  let payments = paymentsCsv
+    .split(/\n/)
+    .map(function (line) {
+      line = line.trim();
+      if (!line) {
+        return null;
+      }
+
+      if (
+        line.startsWith("#") ||
+        line.startsWith("//") ||
+        line.startsWith("-") ||
+        line.startsWith('"') ||
+        line.startsWith("'")
+      ) {
+        return null;
+      }
+
+      let parts = line.split(",");
+      let addr = parts[0] || "";
+      let amount = Dash.toDuff(parts[1] || "");
+
+      if (!addr.startsWith("X")) {
+        console.error(`unknown address: ${addr}`);
+        process.exit(1);
+        return null;
+      }
+
+      if (isNaN(amount) || !amount) {
+        console.error(`unknown amount: ${amount}`);
+        return null;
+      }
+
+      return {
+        address: addr,
+        satoshis: amount,
+      };
+    })
+    .filter(Boolean);
+
+  let changefilename = process.argv[4] || "";
+  if (!changefilename) {
+    console.error(`Usage: pay ./source.wif ./targets.csv ./change.b58c`);
+    process.exit(1);
+    return;
+  }
+  let changeAddr = await Fs.readFile(changefilename, "utf8");
+  changeAddr = changeAddr.trim();
+
+  let tx = await dashApi.createPayments(wif, payments, changeAddr);
+  console.info('Transaction:');
+  console.info(tx.serialize());
+
+  if (!process.argv.includes("--send")) {
+    return;
+  }
+
+  console.info('Instant Send...');
+  await insightApi.instantSend(tx.serialize());
+  console.info('Done');
+}
+
+// Run
+main().catch(function (err) {
+  console.error("Fail:");
+  console.error(err.stack || err);
+  process.exit(1);
+});

lib/dash.js

@@ -100,7 +100,9 @@ Dash.create = function ({
 
     // TODO make more accurate?
     let feePreEstimate = 1000;
-    let utxos = await getOptimalUtxos(utxoAddr, amount + feePreEstimate);
+    let body = await insightApi.getUtxos(utxoAddr);
+    let coreUtxos = await getUtxos(body);
+    let utxos = await getOptimalUtxos(coreUtxos, amount + feePreEstimate);
     let balance = getBalance(utxos);
 
     if (!utxos.length) {
@@ -145,16 +147,89 @@ Dash.create = function ({
     return tx;
   };
 
+  /**
+   * @typedef {Object} CorePayment
+   * @property {(String|import('@dashevo/dashcore-lib').Address)} address
+   * @property {Number} satoshis
+   */
+
+  /**
+   * Send with change back
+   * @param {String} privKey
+   * @param {Array<CorePayment>} payments
+   * @param {(String|import('@dashevo/dashcore-lib').Address)} [changeAddr]
+   */
+  dashApi.createPayments = async function (privKey, payments, changeAddr) {
+    let pk = new Dashcore.PrivateKey(privKey);
+    let utxoAddr = pk.toPublicKey().toAddress().toString();
+    if (!changeAddr) {
+      changeAddr = utxoAddr;
+    }
+
+    // TODO make more accurate?
+    let amount = payments.reduce(function (total, pay) {
+      return pay.satoshis;
+    }, 0);
+    let body = await insightApi.getUtxos(utxoAddr);
+    let coreUtxos = await getUtxos(body);
+    let feePreEstimate = 150 * (payments.length + coreUtxos.length);
+    let utxos = await getOptimalUtxos(coreUtxos, amount + feePreEstimate);
+    let balance = getBalance(utxos);
+
+    if (!utxos.length) {
+      throw new Error(`not enough funds available in utxos for ${utxoAddr}`);
+    }
+
+    // (estimate) don't send dust back as change
+    if (balance - amount <= DUST + FEE) {
+      amount = balance;
+    }
+
+    console.log("DEBUG");
+    console.log(payments, changeAddr);
+
+    //@ts-ignore - no input required, actually
+    let tmpTx = new Transaction()
+      //@ts-ignore - allows single value or array
+      .from(utxos);
+    // TODO update jsdoc for dashcore
+    tmpTx.to(payments, 0);
+    //@ts-ignore - the JSDoc is wrong in dashcore-lib/lib/transaction/transaction.js
+    tmpTx.change(changeAddr);
+    tmpTx.sign(pk);
+
+    // TODO getsmartfeeestimate??
+    // fee = 1duff/byte (2 chars hex is 1 byte)
+    //       +10 to be safe (the tmpTx may be a few bytes off - probably only 4 -
+    //       due to how small numbers are encoded)
+    let fee = 10 + tmpTx.toString().length / 2;
+
+    // (adjusted) don't send dust back as change
+    if (balance + -amount + -fee <= DUST) {
+      amount = balance - fee;
+    }
+
+    //@ts-ignore - no input required, actually
+    let tx = new Transaction()
+      //@ts-ignore - allows single value or array
+      .from(utxos);
+    tx.to(payments, 0);
+    tx.fee(fee);
+    //@ts-ignore - see above
+    tx.change(changeAddr);
+    tx.sign(pk);
+
+    return tx;
+  };
+
   // TODO make more optimal
   /**
-   * @param {String} utxoAddr
+   * @param {Array<CoreUtxo>} utxos
    * @param {Number} fullAmount - including fee estimate
    */
-  async function getOptimalUtxos(utxoAddr, fullAmount) {
+  async function getOptimalUtxos(utxos, fullAmount) {
     // get smallest coin larger than transaction
     // if that would create dust, donate it as tx fee
-    let body = await insightApi.getUtxos(utxoAddr);
-    let utxos = await getUtxos(body);
     let balance = getBalance(utxos);
 
     if (balance < fullAmount) {
@@ -244,3 +319,10 @@ Dash.create = function ({
 
   return dashApi;
 };
+
+/**
+ * @param {String} dash - ex: 0.00000000
+ */
+Dash.toDuff = function (dash) {
+  return Math.round(parseFloat(dash) * DUFFS);
+};