Merge branch 'feature-withdrawal-fee'

9 files changed, 137 insertions, 54 deletions

diff --git a/routes/bitcoin/conversionFee.js b/routes/bitcoin/conversionFee.js
new file mode 100644
index 00000000..9df60c2a
--- /dev/null
+++ b/routes/bitcoin/conversionFee.js
@@ -0,0 +1,12 @@
+// Code for the conversion fee
+// This is in a separate file so that the same function can be used by ./send and ./receive
+
+const conversionFeeMultiplier = 0.01;
+const conversionFeeReceiver = "coinosfees";  // account that receives the fees
+
+/**
+ * Returns the fee you have to pay for withdrawing 'amount' bitcoin.
+ */
+function computeConversionFee(amount) {
+  return Math.floor(amount * conversionFeeMultiplier);
+}
diff --git a/routes/bitcoin/receive.js b/routes/bitcoin/receive.js
index 5bdbcb72..45dadbbe 100644
--- a/routes/bitcoin/receive.js
+++ b/routes/bitcoin/receive.js
@@ -21,8 +21,7 @@ const network =
 const queue = {};
 const seen = [];
 
-// used to calculate how many credits to give
-const withdrawalFeeMultiplier = 0.01;
+const { computeConversionFee } = require('./conversionFee.js');
 
 zmqRawTx.on("message", async (topic, message, sequence) => {
   const hex = message.toString("hex");
@@ -195,7 +194,8 @@ setInterval(async () => {
             { pending: Math.min(account.pending, total) },
             { transaction }
           );
-          await account.increment({ fee_credits: Math.floor(total * withdrawalFeeMultiplier) }, { transaction });
+          // get the # of fee credits you would need to pay off this amount of bitcoin
+          await account.increment({ btc_credits: computeConversionFee(total) }, { transaction });
           await account.reload({ transaction });
           await p.save({ transaction });
 
diff --git a/routes/bitcoin/send.js b/routes/bitcoin/send.js
index a9c95b31..634b223b 100644
--- a/routes/bitcoin/send.js
+++ b/routes/bitcoin/send.js
@@ -1,6 +1,5 @@
 const btc = config.liquid.btcasset;
-const withdrawalFeeMultiplier = 0.01;  // 1% withdrawal fee
-const withdrawalFeeReceiver = "coinosfees";  // account that receives the fees
+let { computeConversionFee, conversionFeeReceiver } = require('./conversionFee.js');
 
 module.exports = ah(async (req, res) => {
   let { user } = req;
@@ -31,10 +30,10 @@ module.exports = ah(async (req, res) => {
   total = total - change + fee;
   let amount = total - fee;
 
-  // get withdrawal fee
-  // 'total' refers to the total before the withdrawal fee
+  // get conversion fee
+  // 'total' refers to the total before the conversion fee
   // (i.e. the total bitcoin that leaves this server)
-  let withdrawalFee = Math.floor(amount * withdrawalFeeMultiplier);
+  let conversionFee = computeConversionFee(amount);
 
   try {
     // withdraw bitcoin
@@ -59,28 +58,28 @@ module.exports = ah(async (req, res) => {
         });
       }
 
+      // use user's credits to reduce fee, if available
+      let conversionFeeDeduction = Math.min(account.btc_credits, conversionFee);
+      if (conversionFeeDeduction) {
+        await account.decrement({ btc_credits: conversionFeeDeduction }, { transaction });
+        await account.reload({ transaction });
+        conversionFee -= conversionFeeDeduction;
+      }
+
       if (total > account.balance) {
         l.error("amount exceeds balance", amount, fee, account.balance);
         throw new Error("low balance");
-      } else if (total + withdrawalFee > account.balance) {
-        l.error("total (after withdrawal fee) exceeds balance", amount, fee, account.balance);
-        throw new Error("low balance (after withdrawal fee)");
-      }
-
-      // use user's credits to reduce fee, if available
-      let withdrawalFeeDeduction = Math.min(account.fee_credits, withdrawalFee);
-      if (withdrawalFeeDeduction) {
-        await account.decrement({ fee_credits: withdrawalFeeDeduction }, { transaction });
-        await account.reload({ transaction });
-        withdrawalFee -= withdrawalFeeDeduction;
+      } else if (total + conversionFee > account.balance) {
+        l.error("total (after conversion fee) exceeds balance", amount, fee, account.balance);
+        throw new Error("low balance (after conversion fee)");
       }
 
-      await account.decrement({ balance: (total + withdrawalFee) }, { transaction });
+      await account.decrement({ balance: (total + conversionFee) }, { transaction });
       await account.reload({ transaction });
 
       let receiverAccount = await db.Account.findOne({
         where: {
-          "$user.username$": withdrawalFeeReceiver
+          "$user.username$": conversionFeeReceiver
         },
         include: [
           {
@@ -93,13 +92,13 @@ module.exports = ah(async (req, res) => {
       });
 
       let fee_payment_id = null;
-      if (withdrawalFee) {
-        await receiverAccount.increment({ balance: withdrawalFee }, { transaction });
+      if (conversionFee) {
+        await receiverAccount.increment({ balance: conversionFee }, { transaction });
         await receiverAccount.reload({ transaction });
         let fee_payment = await db.Payment.create({
-          amount: withdrawalFee,
+          amount: conversionFee,
           fee: 0,
-          memo: "Bitcoin withdrawal fee",
+          memo: "Bitcoin conversion fee",
           account_id: receiverAccount.id,
           user_id: receiverAccount.user_id,
           rate: app.get("rates")[receiverAccount.user.currency],
diff --git a/routes/lightning/conversionFee.js b/routes/lightning/conversionFee.js
new file mode 100644
index 00000000..7359bb3f
--- /dev/null
+++ b/routes/lightning/conversionFee.js
@@ -0,0 +1,12 @@
+// Code for the conversion fee
+// This is in a separate file so that the same function can be used by ./send and ./receive
+
+const conversionFeeMultiplier = 0.01;
+const conversionFeeReceiver = "coinosfees";  // account that receives the fees
+
+/**
+ * Returns the fee you have to pay for withdrawing 'amount' lightning BTC.
+ */
+function computeConversionFee(amount) {
+  return Math.floor(amount * conversionFeeMultiplier);
+}
diff --git a/routes/lightning/receive.js b/routes/lightning/receive.js
index 6723d577..6d10eb9b 100644
--- a/routes/lightning/receive.js
+++ b/routes/lightning/receive.js
@@ -1,3 +1,5 @@
+const { computeConversionFee } = require('./conversionFee.js');
+
 const handlePayment = async (msg) => {
   l.info("incoming lightning payment", msg.value, msg.payment_request, msg.settled);
   if (!msg.settled) return;
@@ -60,6 +62,8 @@ const handlePayment = async (msg) => {
       invoice.received += total;
 
       await account.increment({ balance: total }, { transaction });
+      // get the # of fee credits you would need to pay off this amount of bitcoin
+      await account.increment({ btc_credits: computeConversionFee(total) }, { transaction });
       await account.reload({ transaction });
       await invoice.save({ transaction });
       await payment.save({ transaction });
diff --git a/routes/liquid/conversionFee.js b/routes/liquid/conversionFee.js
new file mode 100644
index 00000000..d365185b
--- /dev/null
+++ b/routes/liquid/conversionFee.js
@@ -0,0 +1,12 @@
+// Code for the conversion fee
+// This is in a separate file so that the same function can be used by ./send and ./receive
+
+const conversionFeeMultiplier = 0.01;
+const conversionFeeReceiver = "coinosfees";  // account that receives the fees
+
+/**
+ * Returns the fee you have to pay for withdrawing 'amount' L-BTC.
+ */
+function computeConversionFee(amount) {
+  return Math.floor(amount * conversionFeeMultiplier);
+}
diff --git a/routes/liquid/receive.js b/routes/liquid/receive.js
index 9650e5b7..2bd86805 100644
--- a/routes/liquid/receive.js
+++ b/routes/liquid/receive.js
@@ -13,8 +13,7 @@ const network =
     config.liquid.network === "mainnet" ? "liquid" : config.liquid.network
   ];
 
-// used to calculate how many credits to give
-const withdrawalFeeMultiplier = 0.01;
+const { computeConversionFee } = require('./conversionFee.js');
 
 const getAccount = async (params, transaction) => {
   let account = await db.Account.findOne({
@@ -344,7 +343,7 @@ setInterval(async () => {
             { pending: Math.min(p.account.pending, total) },
             { transaction }
           );
-          await p.account.increment({ fee_credits: Math.floor(total * withdrawalFeeMultiplier) }, { transaction });
+          await p.account.increment({ liquid_credits: computeConversionFee(total) }, { transaction });
           await p.account.reload({ transaction });
 
           await p.save({ transaction });
diff --git a/routes/liquid/send.js b/routes/liquid/send.js
index fcb05942..254972ad 100644
--- a/routes/liquid/send.js
+++ b/routes/liquid/send.js
@@ -1,8 +1,7 @@
 const btc = config.liquid.btcasset;
 const lcad = config.liquid.cadasset;
 const { Transaction } = require("liquidjs-lib");
-const withdrawalFeeMultiplier = 0.01;  // 1% withdrawal fee
-const withdrawalFeeReceiver = "coinosfees";  // 1% withdrawal fee
+const { computeConversionFee, conversionFeeReceiver } = require('./conversionFee.js');
 
 sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
   try {
@@ -84,10 +83,10 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
           total += fee - covered;
         }
 
-        // get withdrawal fee
-        // 'total' refers to the total before the withdrawal fee
+        // get conversion fee
+        // 'total' refers to the total before the conversion fee
         // (i.e. the total liquid bitcoin that leaves this server)
-        var withdrawalFee = Math.floor(amount * withdrawalFeeMultiplier);
+        var conversionFee = computeConversionFee(amount);
 
         if (limit && total > limit + fee)
           throw new Error("Tx amount exceeds authorized amount");
@@ -106,6 +105,14 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
             transaction
           });
 
+          // use user's credits to reduce fee, if available
+          let conversionFeeDeduction = Math.min(account.liquid_credits, conversionFee);
+          if (conversionFeeDeduction) {
+            await account.decrement({ liquid_credits: conversionFeeDeduction }, { transaction });
+            await account.reload({ transaction });
+            conversionFee -= conversionFeeDeduction;
+          }
+
           if (total > account.balance) {
             l.warn("amount exceeds balance", {
               total,
@@ -117,35 +124,26 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
                 account.ticker === "BTC" ? "SAT" : account.ticker
               }, have ${account.balance}`
             );
-          } else if (total + withdrawalFee > account.balance) {
-            l.warn("amount plus withdrawal fee exceeds balance", {
+          } else if (total + conversionFee > account.balance) {
+            l.warn("amount plus conversion fee exceeds balance", {
               total,
               fee,
-              withdrawalFee,
+              conversionFee,
               balance: account.balance
             });
             throw new Error(
-              `Insufficient funds, need ${total + withdrawalFee} ${
+              `Insufficient funds, need ${total + conversionFee} ${
                 account.ticker === "BTC" ? "SAT" : account.ticker
               }, have ${account.balance}`
             );
           }
 
-          // use user's credits to reduce fee, if available
-          console.log(account.fee_credits);
-          let withdrawalFeeDeduction = Math.min(account.fee_credits, withdrawalFee);
-          if (withdrawalFeeDeduction) {
-            await account.decrement({ fee_credits: withdrawalFeeDeduction }, { transaction });
-            await account.reload({ transaction });
-            withdrawalFee -= withdrawalFeeDeduction;
-          }
-
-          await account.decrement({ balance: (total + withdrawalFee)}, { transaction });
+          await account.decrement({ balance: (total + conversionFee)}, { transaction });
           await account.reload({ transaction });
 
           let receiverAccount = await db.Account.findOne({
             where: {
-              "$user.username$": withdrawalFeeReceiver
+              "$user.username$": conversionFeeReceiver
             },
             include: [
               {
@@ -158,13 +156,13 @@ sendLiquid = async ({ asset, amount, user, address, memo, tx, limit }) => {
           });
 
           let fee_payment_id = null;
-          if (withdrawalFee) {
-            await receiverAccount.increment({ balance: withdrawalFee }, { transaction });
+          if (conversionFee) {
+            await receiverAccount.increment({ balance: conversionFee }, { transaction });
             await receiverAccount.reload({ transaction });
             let fee_payment = {
-              amount: withdrawalFee,
+              amount: conversionFee,
               fee: 0,
-              memo: "Liquid withdrawal fee",
+              memo: "Liquid conversion fee",
               account_id: receiverAccount.id,
               user_id: receiverAccount.user_id,
               rate: app.get("rates")[receiverAccount.user.currency],
diff --git a/routes/lnurl.js b/routes/lnurl.js
index 0466e143..93d939f9 100644
--- a/routes/lnurl.js
+++ b/routes/lnurl.js
@@ -12,6 +12,8 @@ withdrawals = persist("data/withdrawals.json");
 
 lnurlServer = lnurl.createServer(config.lnurl);
 
+let { computeConversionFee, conversionFeeReceiver } = require('lightning/conversionFee.js');
+
 var optionalAuth = function(req, res, next) {
   passport.authenticate("jwt", { session: false }, function(err, user, info) {
     req.user = user;
@@ -391,6 +393,7 @@ lnurlServer.bindToHook(
         try {
           let decoded = await lnp.decodePayReq({ pay_req: pr });
           let amount = decoded.num_satoshis;
+          let conversionFee = computeConversionFee(amount);
 
           await db.transaction(async transaction => {
             let account = await db.Account.findOne({
@@ -402,8 +405,51 @@ lnurlServer.bindToHook(
               transaction
             });
 
+            // account that receives conversion fees
+            let receiverAccount = await db.Account.findOne({
+              where: {
+                "$user.username$": conversionFeeReceiver
+              },
+              include: [
+                {
+                  model: db.User,
+                  as: "user"
+                },
+              ],
+              lock: transaction.LOCK.UPDATE,
+              transaction
+            });
+
+            let conversionFeeDeduction = Math.min(account.lightning_credits, conversionFee);
+            if (conversionFeeDeduction) {
+              await account.decrement({ lightning_credits: conversionFeeDeduction }, { transaction });
+              await account.reload({ transaction });
+              conversionFee -= conversionFeeDeduction;
+            }
+
             if (account.balance < amount) {
               throw new Error("Insufficient funds");
+            } else if (account.balance < amount + conversionFee) {
+              throw new Error("Insufficient funds for conversion fee");
+            }
+
+            let fee_payment_id = null;
+            if (conversionFee) {
+              await receiverAccount.increment({ balance: conversionFee }, { transaction });
+              await receiverAccount.reload({ transaction });
+              let fee_payment = await db.Payment.create({
+                amount: conversionFee,
+                fee: 0,
+                memo: "Bitcoin conversion fee",
+                account_id: receiverAccount.id,
+                user_id: receiverAccount.user_id,
+                rate: app.get("rates")[receiverAccount.user.currency],
+                currency: receiverAccount.user.currency,
+                confirmed: true,
+                received: true,
+                network: "COINOS"
+              }, { transaction });
+              fee_payment_id = fee_payment.id;
             }
 
             let payment = await db.Payment.create(
@@ -415,7 +461,8 @@ lnurlServer.bindToHook(
                 rate: app.get("rates")[user.currency],
                 currency: user.currency,
                 confirmed: true,
-                network: "lightning"
+                network: "lightning",
+                fee_payment_id: fee_payment_id
               },
               { transaction }
             );
@@ -447,7 +494,7 @@ lnurlServer.bindToHook(
               }
             }, 1000);
 
-            await account.decrement({ balance: amount }, { transaction });
+            await account.decrement({ balance: (amount + conversionFee) }, { transaction });
             await account.reload({ transaction });
 
             let p = payment.get({ plain: true });