feat: added liquid withdrawal

5 files changed, 138 insertions, 74 deletions

diff --git a/lib/feeliquidtx.js b/lib/feeliquidtx.js
new file mode 100644
index 00000000..d32623ab
--- /dev/null
+++ b/lib/feeliquidtx.js
@@ -0,0 +1,13 @@
+module.exports = async (txid) => {
+    const tx = await lq.getRawTransaction(txid);
+    const transaction = await lq.decodeRawTransaction(tx);
+    let valueOut = 0;
+
+    transaction.vout.forEach(o => {
+        if (o.scriptPubKey.type === 'fee') {
+            valueOut = o.value;
+        }
+    });
+
+    return toSats(valueOut);
+}
diff --git a/routes/liquid/send.js b/routes/liquid/send.js
index 0c0b2012..6df430de 100644
--- a/routes/liquid/send.js
+++ b/routes/liquid/send.js
@@ -1,6 +1,7 @@
 const btc = config.liquid.btcasset;
 const lcad = config.liquid.cadasset;
 const { Transaction } = require("@asoltys/liquidjs-lib");
+const decrementAccount = require('./util/decrementacc');
 
 sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
   l.info("sending liquid", amount, address);
@@ -54,81 +55,9 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
       let asset = assets[i];
       let amount = totals[asset];
       if (change[asset]) amount -= change[asset];
-      let total = amount;
 
-      if (asset === btc) {
-        let covered = 0;
-        let nonbtc = assets.filter(a => a !== btc);
-        if (nonbtc.length === 1) {
-          let faucet = await db.Account.findOne({
-            where: {
-              asset: nonbtc[0],
-              user_id: null
-            },
-            lock: transaction.LOCK.UPDATE,
-            transaction
-          });
-
-          if (faucet) {
-            covered = faucet.balance;
-            if (covered > fee) covered = fee;
-            await faucet.decrement({ balance: covered }, { transaction });
-            await faucet.reload({ transaction });
-            await faucet.save({ transaction });
-          }
-        }
-
-        total += fee - covered;
-      }
-
-      if (limit && total > limit + fee)
-        throw new Error("Tx amount exceeds authorized amount");
-
-      if (asset !== btc || total) {
-        l.info("creating liquid payment", user.username, asset, total, fee);
-
-        let account = await db.Account.findOne({
-          where: {
-            user_id: user.id,
-            asset,
-            pubkey: null
-          },
-          lock: transaction.LOCK.UPDATE,
-          order: [["balance", "DESC"]],
-          transaction
-        });
-
-        if (total > account.balance) {
-          l.warn("amount exceeds balance", {
-            total,
-            fee,
-            balance: account.balance
-          });
-          throw new Error(
-            `Insufficient funds, need ${total} ${
-              account.ticker === "BTC" ? "SAT" : account.ticker
-            }, have ${account.balance}`
-          );
-        }
-
-        await account.decrement({ balance: total }, { transaction });
-        await account.reload({ transaction });
-
-        let payment = {
-          amount: -amount,
-          account_id: account.id,
-          fee,
-          memo,
-          user_id: user.id,
-          rate: app.get("rates")[user.currency],
-          currency: user.currency,
-          address,
-          confirmed: true,
-          received: false,
-          network: "liquid"
-        };
-
-        payment.account = account;
+      const payment = await decrementAccount(user, transaction, limit, fee, assets, amount, address, memo, asset);
+      if(payment) {
         payments.push(payment);
       }
     }
diff --git a/routes/liquid/util/decrementacc.js b/routes/liquid/util/decrementacc.js
new file mode 100644
index 00000000..5be30e13
--- /dev/null
+++ b/routes/liquid/util/decrementacc.js
@@ -0,0 +1,86 @@
+const btc = config.liquid.btcasset;
+
+module.exports = async (user, transaction, limit, fee, assets, amount, address, memo, asset) => {
+    let total = amount;
+
+    if (asset === btc) {
+        let covered = 0;
+        let nonbtc = assets.filter(a => a !== btc);
+        if (nonbtc.length === 1) {
+            let faucet = await db.Account.findOne({
+                where: {
+                    asset: nonbtc[0],
+                    user_id: null
+                },
+                lock: transaction.LOCK.UPDATE,
+                transaction
+            });
+
+            if (faucet) {
+                // TODO: is faucet ok with 0 fee in withdraw?
+                covered = faucet.balance;
+                if (covered > fee) covered = fee;
+                // covered = fee;
+                // if (covered > faucet.balance) covered = faucet.balance;
+                await faucet.decrement({balance: covered}, {transaction});
+                await faucet.reload({transaction});
+                await faucet.save({transaction});
+            }
+        }
+
+        total += fee - covered;
+    }
+
+    if (limit && total > limit + fee)
+        throw new Error("Tx amount exceeds authorized amount");
+
+    if (asset !== btc || total) {
+        l.info("creating liquid payment", user.username, asset, total, fee);
+
+        let account = await db.Account.findOne({
+            where: {
+                user_id: user.id,
+                asset,
+                pubkey: null
+            },
+            lock: transaction.LOCK.UPDATE,
+            order: [["balance", "DESC"]],
+            transaction
+        });
+
+        if (total > account.balance) {
+            l.warn("amount exceeds balance", {
+                total,
+                fee,
+                balance: account.balance
+            });
+            throw new Error(
+                `Insufficient funds, need ${total} ${
+                    account.ticker === "BTC" ? "SAT" : account.ticker
+                }, have ${account.balance}`
+            );
+        }
+
+        await account.decrement({balance: total}, {transaction});
+        await account.reload({transaction});
+
+        let payment = {
+            amount: -amount,
+            account_id: account.id,
+            fee,
+            memo,
+            user_id: user.id,
+            rate: app.get("rates")[user.currency],
+            currency: user.currency,
+            address,
+            confirmed: true,
+            received: false,
+            network: "liquid"
+        };
+
+        payment.account = account;
+        return payment;
+    }
+
+    return null;
+};
diff --git a/routes/liquid/withdraw.js b/routes/liquid/withdraw.js
new file mode 100644
index 00000000..ec67091f
--- /dev/null
+++ b/routes/liquid/withdraw.js
@@ -0,0 +1,35 @@
+const btc = config.liquid.btcasset;
+const getFee = require('../../lib/feeliquidtx');
+const decrementAccount = require('./util/decrementacc');
+
+module.exports = ah(async (req, res) => {
+    let {user} = req;
+    let {asset = btc, address, amount, memo} = req.body;
+
+    let payment;
+    try {
+        await db.transaction(async transaction => {
+            payment = await decrementAccount(user, transaction, toSats(amount), 0, [asset], toSats(amount), address, memo, asset);
+
+            const txid = (await lq.sendToAddress(address, amount, 'withdrawal', memo, true));
+            const fee = await getFee(txid);
+
+            if(payment) {
+                payment.fee = fee;
+                const { account } = payment;
+
+                await db.Payment.create(payment, {transaction});
+
+                emit(user.username, "account", account.get({ plain: true }));
+                emit(user.username, "payment", payment);
+            }
+
+        });
+
+        l.info("withdraw liquid", user.username, amount);
+        res.send(payment);
+    } catch (e) {
+        l.error("error withdrawing liquid", e.message);
+        return res.status(500).send(e.message);
+    }
+});
diff --git a/routes/payments.js b/routes/payments.js
index dc651b39..cb09de63 100644
--- a/routes/payments.js
+++ b/routes/payments.js
@@ -164,6 +164,7 @@ ah(async () => {
     app.get("/liquid/generate", auth, require("./liquid/generate"));
     app.post("/liquid/fee", auth, require("./liquid/fee"));
     app.post("/liquid/send", auth, require("./liquid/send"));
+    app.post("/liquid/withdraw", auth, require("./liquid/withdraw"));
     app.post("/taxi", auth, require("./liquid/taxi"));
     require("./liquid/receive");