liquid support

1 files changed, 97 insertions, 0 deletions

diff --git a/sendLiquid.js b/sendLiquid.js
new file mode 100644
index 00000000..cdfad4a1
--- /dev/null
+++ b/sendLiquid.js
@@ -0,0 +1,97 @@
+const bitcoin = require("bitcoinjs-lib");
+const config = require("./config");
+const reverse = require("buffer-reverse");
+const BitcoinCore = require("bitcoin-core");
+
+const l = console.log;
+const SATS = 100000000;
+
+const bc = new BitcoinCore(config.liquid);
+
+module.exports = (app, db, emit) => async (req, res) => {
+  let { address, amount } = req.body;
+  let rawtx, hex, fee;
+  l(address, amount);
+
+  try {
+    amount = parseInt(amount);
+
+    rawtx = await bc.createRawTransaction([], {
+      [address]: (amount / SATS).toFixed(8)
+    });
+
+    l("funding", rawtx, amount, req.user.balance);
+
+    rawtx = await bc.fundRawTransaction(rawtx, {
+      subtractFeeFromOutputs: amount === req.user.balance ? [0] : []
+    });
+    l("raw tx", rawtx.hex);
+
+    hex = await bc.blindRawTransaction(rawtx.hex);
+
+    ({ fee } = rawtx);
+    fee = parseInt(fee * SATS);
+  } catch (e) {
+    l("wawaw", e);
+    return res.status(500).send(e.message);
+  }
+
+  try {
+    await db.transaction(async transaction => {
+      let { balance } = await db.User.findOne({
+        where: {
+          username: req.user.username
+        },
+        lock: transaction.LOCK.UPDATE,
+        transaction
+      });
+
+      if (amount !== balance && amount + fee > balance) {
+        l("amount exceeds balance", amount, fee, balance);
+        throw new Error("insufficient funds");
+      }
+
+      req.user.balance -= amount + fee;
+      await req.user.save({ transaction });
+    });
+  } catch (e) {
+    l(e);
+    return res.status(500).send("Not enough satoshis");
+  }
+
+  try {
+    if (config.bitcoin.walletpass)
+      await bc.walletPassphrase(config.bitcoin.walletpass, 300);
+
+    rawtx = (await bc.signRawTransactionWithWallet(hex)).hex;
+    let txid = await bc.sendRawTransaction(rawtx);
+
+    let total = Math.min(amount + fee, req.user.balance);
+    if (req.user.balance < 0) req.user.balance = 0;
+
+    await db.transaction(async transaction => {
+      await req.user.save({ transaction });
+      emit(req.user.username, "user", req.user);
+
+      const payment = await db.Payment.create(
+        {
+          amount: -total,
+          user_id: req.user.id,
+          hash: txid,
+          rate: app.get("ask"),
+          currency: "CAD",
+          address,
+          confirmed: 1
+        },
+        { transaction }
+      );
+
+      emit(req.user.username, "payment", payment);
+    });
+
+    res.send({ txid, amount, fees: fee });
+  } catch (e) {
+    l(e);
+    return res.status(500).send(e.message);
+  }
+};