Implement market settlement

db/init.sql

@@ -31,6 +31,7 @@ CREATE TABLE markets(
     id SERIAL PRIMARY KEY,
     description TEXT NOT NULL,
     end_date TIMESTAMP WITH TIME ZONE NOT NULL,
+    settled_at TIMESTAMP WITH TIME ZONE,
     pubkey TEXT NOT NULL REFERENCES users(pubkey),
     invoice_id UUID NOT NULL UNIQUE REFERENCES invoices(id)
 );

db/market.go

@@ -28,7 +28,7 @@ func (db *DB) CreateMarket(tx *sql.Tx, ctx context.Context, market *Market) erro
 }
 
 func (db *DB) FetchMarket(marketId int, market *Market) error {
-	if err := db.QueryRow("SELECT id, description, end_date, pubkey FROM markets WHERE id = $1", marketId).Scan(&market.Id, &market.Description, &market.EndDate, &market.Pubkey); err != nil {
+	if err := db.QueryRow("SELECT id, description, end_date, pubkey, settled_at FROM markets WHERE id = $1", marketId).Scan(&market.Id, &market.Description, &market.EndDate, &market.Pubkey, &market.SettledAt); err != nil {
 		return err
 	}
 	return nil
@@ -324,6 +324,8 @@ func (db *DB) FetchUserBalance(tx *sql.Tx, ctx context.Context, marketId int, pu
 		"LEFT JOIN invoices i ON i.id = o.invoice_id " +
 		"JOIN shares s ON s.id = o.share_id " +
 		"WHERE o.pubkey = $1 AND s.market_id = $2 AND o.deleted_at IS NULL " +
+		// TODO: is there a bug here? shouldn't i also check that SELL orders have no order_id set?
+		//   (also see user payout query during market settlement)
 		"AND ( (o.side = 'BUY' AND i.confirmed_at IS NOT NULL AND o.order_id IS NOT NULL) OR o.side = 'SELL' ) " +
 		"GROUP BY o.pubkey, s.description"
 	rows, err := tx.QueryContext(ctx, query, pubkey, marketId)

db/types.go

@@ -29,11 +29,12 @@ type (
 		Id          Serial    `json:"id"`
 		Description string    `json:"description"`
 		EndDate     time.Time `json:"endDate"`
+		SettledAt   null.Time `json:"settledAt"`
 		Pubkey      string    `json:"pubkey"`
 		InvoiceId   UUID
 	}
 	Share struct {
-		Id          UUID
+		Id          UUID `json:"sid"`
 		MarketId    int
 		Description string
 	}

lnd/invoice.go

@@ -115,13 +115,24 @@ func (lnd *LNDClient) CheckInvoice(d *db.DB, hash lntypes.Hash) {
 
 			// Run matchmaking if an order was paid
 			var orderId string
+			var deleted bool
 			if err = d.QueryRowContext(ctx,
-				"SELECT o.id FROM orders o WHERE invoice_id = (SELECT i.id FROM invoices i WHERE hash = $1)",
+				"SELECT o.id, o.deleted_at IS NOT NULL FROM orders o WHERE invoice_id = (SELECT i.id FROM invoices i WHERE hash = $1)",
 				hash.String(),
-			).Scan(&orderId); err != nil && err != sql.ErrNoRows {
+			).Scan(&orderId, &deleted); err != nil && err != sql.ErrNoRows {
 				handleLoopError(err)
 				continue
 			}
+			if deleted {
+				// order was canceled before it was paid. refund sats immediately.
+				// this can happen if the market was settled between creating the order and paying the corresponding invoice.
+				if _, err := tx.ExecContext(ctx, "UPDATE users SET msats = msats + $1", int64(lnInvoice.AmountPaid)); err != nil {
+					tx.Rollback()
+					break
+				}
+				log.Printf("order %s canceled. refunded sats to user.", orderId)
+				break
+			}
 			if orderId != "" {
 				go d.RunMatchmaking(orderId)
 			}

server/router/handler/market.go

@@ -46,6 +46,7 @@ func HandleMarket(sc context.ServerContext) echo.HandlerFunc {
 			"Id":          market.Id,
 			"Pubkey":      market.Pubkey,
 			"Description": market.Description,
+			"SettledAt":   market.SettledAt,
 			"Shares":      shares,
 		}
 		if session := c.Get("session"); session != nil {
@@ -154,6 +155,7 @@ func HandleOrder(sc context.ServerContext) echo.HandlerFunc {
 			u           db.User
 			o           db.Order
 			s           db.Share
+			m           db.Market
 			invoice     *db.Invoice
 			msats       int64
 			description string
@@ -181,12 +183,21 @@ func HandleOrder(sc context.ServerContext) echo.HandlerFunc {
 			tx.Rollback()
 			return err
 		}
+
+		if err = sc.Db.FetchMarket(s.MarketId, &m); err == sql.ErrNoRows {
+			return c.JSON(http.StatusNotFound, nil)
+		} else if err != nil {
+			return err
+		}
+
+		if m.SettledAt.Valid {
+			return c.JSON(http.StatusBadRequest, map[string]string{"reason": "market already settled"})
+		}
+
 		description = fmt.Sprintf("%s %d %s shares @ %d sats [market:%d]", strings.ToUpper(o.Side), o.Quantity, s.Description, o.Price, s.MarketId)
 
 		if o.Side == "BUY" {
-			// === Create invoice ===
+			// BUY orders require payment
-			// We do this for BUY and SELL orders such that we can continue to use `invoice.confirmed_at IS NOT NULL`
-			// to check for confirmed orders
 			if invoice, err = sc.Lnd.CreateInvoice(tx, ctx, sc.Db, o.Pubkey, msats, description); err != nil {
 				tx.Rollback()
 				return err
@@ -347,3 +358,107 @@ func HandleMarketStats(sc context.ServerContext) echo.HandlerFunc {
 		return c.JSON(http.StatusOK, stats)
 	}
 }
+
+func HandleMarketSettlement(sc context.ServerContext) echo.HandlerFunc {
+	return func(c echo.Context) error {
+		var (
+			marketId int64
+			market   db.Market
+			s        db.Share
+			tx       *sql.Tx
+			u        db.User
+			err      error
+		)
+		if marketId, err = strconv.ParseInt(c.Param("id"), 10, 64); err != nil {
+			return c.JSON(http.StatusBadRequest, nil)
+		}
+
+		if err = c.Bind(&s); err != nil || s.Id == "" {
+			return c.JSON(http.StatusBadRequest, nil)
+		}
+
+		if err = sc.Db.FetchMarket(int(marketId), &market); err == sql.ErrNoRows {
+			return c.JSON(http.StatusNotFound, map[string]string{"reason": "market not found"})
+		} else if err != nil {
+			return err
+		}
+
+		u = c.Get("session").(db.User)
+
+		// only market owner can settle market
+		if market.Pubkey != u.Pubkey {
+			return c.JSON(http.StatusForbidden, map[string]string{"reason": "not your market"})
+		}
+
+		// market already settled?
+		if market.SettledAt.Valid {
+			return c.JSON(http.StatusBadRequest, map[string]string{"reason": "market already settled"})
+		}
+
+		// transaction start
+		ctx, cancel := context_.WithTimeout(c.Request().Context(), 10*time.Second)
+		defer cancel()
+		if tx, err = sc.Db.BeginTx(ctx, nil); err != nil {
+			return err
+		}
+		defer tx.Commit()
+
+		query := "" +
+			"WITH " +
+			"  pending_orders AS ( " +
+			"    SELECT o.id, o.side, o.pubkey, i.msats_received FROM orders o " +
+			"    LEFT JOIN invoices i ON i.id = o.invoice_id" +
+			"    JOIN shares s ON s.id = o.share_id " +
+			"    WHERE s.market_id = $1 " +
+			"    AND o.deleted_at IS NULL AND o.order_id IS NULL " +
+			"  ), " +
+			"  update_users_refund AS ( " +
+			"    UPDATE users u " +
+			"    SET msats = msats + po.msats_received " +
+			"    FROM ( " +
+			"      SELECT pubkey, msats_received " +
+			"      FROM pending_orders " +
+			"      WHERE msats_received IS NOT NULL" +
+			"    ) AS po " +
+			"    WHERE po.pubkey = u.pubkey " +
+			"    RETURNING u.pubkey::TEXT " +
+			"  ), " +
+			"  user_shares AS ( " +
+			"    SELECT o.pubkey, o.share_id, " +
+			"    SUM(CASE WHEN o.side = 'BUY' THEN o.quantity ELSE -o.quantity END) AS sum " +
+			"    FROM orders o " +
+			"    LEFT JOIN invoices i ON i.id = o.invoice_id " +
+			"    JOIN shares s ON s.id = o.share_id " +
+			"    WHERE s.market_id = $1 AND o.deleted_at IS NULL AND s.id = $2" +
+			"    AND ( (o.side = 'BUY' AND i.confirmed_at IS NOT NULL AND o.order_id IS NOT NULL) OR o.side = 'SELL' ) " +
+			"    GROUP BY o.pubkey, o.share_id " +
+			"  ), " +
+			"  update_users_payout AS ( " +
+			"    UPDATE users u " +
+			"    SET msats = msats + (us.sum * 100 * 1000) " +
+			"    FROM (SELECT pubkey, sum FROM user_shares) us " +
+			"    WHERE u.pubkey = us.pubkey " +
+			"    RETURNING u.pubkey::TEXT " +
+			"  ), " +
+			"  update_orders AS ( " +
+			"    UPDATE orders o " +
+			"    SET deleted_at = CURRENT_TIMESTAMP " +
+			"    WHERE id IN (SELECT id FROM pending_orders) " +
+			"    RETURNING o.id::TEXT " +
+			"  ) " +
+			"SELECT * FROM update_users_refund UNION SELECT * FROM update_users_payout UNION SELECT * FROM update_orders"
+		if _, err = tx.ExecContext(ctx, query, marketId, s.Id); err != nil {
+			tx.Rollback()
+			return err
+		}
+
+		if _, err = tx.ExecContext(ctx, "UPDATE markets SET settled_at = CURRENT_TIMESTAMP WHERE id = $1", marketId); err != nil {
+			tx.Rollback()
+			return err
+		}
+
+		tx.Commit()
+
+		return c.JSON(http.StatusOK, nil)
+	}
+}

server/router/router.go

@@ -48,6 +48,10 @@ func addBackendRoutes(e *echo.Echo, sc ServerContext) {
 	GET(e, sc, "/api/market/:id", handler.HandleMarket)
 	GET(e, sc, "/api/market/:id/orders", handler.HandleMarketOrders)
 	GET(e, sc, "/api/market/:id/stats", handler.HandleMarketStats)
+	POST(e, sc, "/api/market/:id/settle",
+		handler.HandleMarketSettlement,
+		middleware.SessionGuard,
+		middleware.LNDGuard)
 	POST(e, sc, "/api/order",
 		handler.HandleOrder,
 		middleware.SessionGuard,

vue/src/components/Market.vue

@@ -9,6 +9,9 @@
 |_| |_| |_|\__,_|_|  |_|\_\___|\__|</pre>
   </div>
   <div class="font-mono">{{ market.Description }}</div>
+  <div v-if="!!market.SettledAt" class="label error font-mono m-auto my-3">
+    <div>Settled</div>
+  </div>
   <!-- eslint-enable -->
   <header class="flex flex-row text-center justify-center pt-1">
     <nav>

vue/src/components/MarketSettings.vue

@@ -14,7 +14,7 @@
         </p>
         <p class="red"><b>You cannot undo this action.</b></p>
       </div>
-      <button class="col-span-2" v-if="selected" @click.prevent="confirm">confirm</button>
+      <button class="col-span-2" v-if="selected" @click.prevent="confirm" :disabled="!!market.SettledAt">confirm</button>
     </div>
     <div v-if="err" class="red text-center">{{ err }}</div>
     <div v-if="success" class="green text-center">{{ success }}</div>
@@ -39,11 +39,19 @@ const click = (sel) => {
 }
 
 const confirm = async () => {
-  const sid = market.value.Shares.find(s => s.Description === selected.value).Id
+  success.value = null
+  err.value = null
+  const sid = market.value.Shares.find(s => s.Description === selected.value).sid
   const url = '/api/market/' + market.value.Id + '/settle'
   const body = JSON.stringify({ sid })
   try {
-    await fetch(url, { method: 'POST', headers: { 'Content-type': 'application/json' }, body })
+    const res = await fetch(url, { method: 'POST', headers: { 'Content-type': 'application/json' }, body })
+    if (res.status === 200) {
+      success.value = 'Market settled'
+      return
+    }
+    const resBody = await res.json()
+    err.value = resBody.reason || `error: server responded with HTTP ${res.status}`
   } catch (err) {
     console.error(err)
   }

vue/src/components/OrderForm.vue

@@ -21,7 +21,7 @@
       <label>{{ format(buyCost) }} sats</label>
       <label>if you win:</label>
       <label>+{{ format(buyProfit) }} sats</label>
-      <button class="col-span-2" type="submit">submit buy order</button>
+      <button class="col-span-2" type="submit" :disabled="!!market.SettledAt">submit buy order</button>
     </form>
     <form v-else v-show="showForm" @submit.prevent="submitSellForm">
       <label v-if="session.isAuthenticated">you have:</label>
@@ -37,7 +37,9 @@
       <label>{{ sellShares }} {{ selected }} shares @ {{ format(sellPrice) }} sats</label>
       <label>you make:</label>
       <label>+{{ format(sellProfit) }} sats</label>
-      <button class="col-span-2" type="submit" :disabled="userShares === 0">submit sell order</button>
+      <button class="col-span-2" type="submit" :disabled="userShares === 0 || !!market.SettledAt">
+        submit sell order
+      </button>
     </form>
     <div v-if="err" class="red text-center">{{ err }}</div>
     <div v-if="success" class="green text-center">{{ success }}</div>
@@ -46,13 +48,14 @@
 
 <script setup>
 import { useSession } from '@/stores/session'
-import { ref, computed } from 'vue'
+import { ref, computed, defineProps } from 'vue'
 import { useRoute, useRouter } from 'vue-router'
 
+const props = defineProps(['market'])
+const market = ref(props.market)
 const session = useSession()
 const router = useRouter()
 const route = useRoute()
-const marketId = route.params.id
 
 // YES NO button logic
 // -- which button was pressed?
@@ -108,23 +111,13 @@ const sold = ref(0)
 
 const format = (x, i = 3) => x === null ? null : x >= 1 ? Math.round(x) : x === 0 ? x : x.toFixed(i)
 
-// Fetch market data
-const market = ref(null)
-const url = '/api/market/' + marketId
-await fetch(url)
-  .then(r => r.json())
-  .then(body => {
-    market.value = body
-  })
-  .catch(console.error)
-
 // Currently, we only support binary markets.
 // (only events which can be answered with YES and NO)
 const yesShareId = computed(() => {
-  return market?.value.Shares.find(s => s.Description === 'YES').Id
+  return market?.value.Shares.find(s => s.Description === 'YES').sid
 })
 const noShareId = computed(() => {
-  return market?.value.Shares.find(s => s.Description === 'NO').Id
+  return market?.value.Shares.find(s => s.Description === 'NO').sid
 })
 const shareId = computed(() => {
   return selected.value === 'YES' ? yesShareId.value : noShareId.value
@@ -143,7 +136,7 @@ const submitBuyForm = async () => {
   const res = await fetch(url, { method: 'POST', headers: { 'Content-type': 'application/json' }, body })
   const resBody = await res.json()
   if (res.status !== 402) {
-    err.value = `error: server responded with HTTP ${resBody.status}`
+    err.value = `error: server responded with HTTP ${res.status}`
     return
   }
   const invoiceId = resBody.id