delphi.market/server/router/handler/market.go

323 lines
10 KiB
Go

package handler
import (
"database/sql"
"fmt"
"math"
"net/http"
"strconv"
"time"
"git.ekzyis.com/ekzyis/delphi.market/lib/lmsr"
"git.ekzyis.com/ekzyis/delphi.market/server/router/context"
"git.ekzyis.com/ekzyis/delphi.market/server/router/pages"
"git.ekzyis.com/ekzyis/delphi.market/server/router/pages/components"
"git.ekzyis.com/ekzyis/delphi.market/types"
"github.com/a-h/templ"
"github.com/labstack/echo/v4"
"github.com/lightningnetwork/lnd/lnrpc/invoicesrpc"
"github.com/lightningnetwork/lnd/lntypes"
"github.com/lightningnetwork/lnd/lnwire"
)
func HandleCreate(sc context.Context) echo.HandlerFunc {
return func(c echo.Context) error {
var (
db = sc.Db
lnd = sc.Lnd
tx *sql.Tx
ctx = c.Request().Context()
u = c.Get("session").(types.User)
question = c.FormValue("question")
description = c.FormValue("description")
endDate = c.FormValue("end_date")
hash lntypes.Hash
paymentRequest string
cost = lnwire.MilliSatoshi(10_000e3) // creating a market costs 10k sats
// The cost is used to fund the market.
// Maximum possible amount of money the market maker can lose is b*ln2.
// This means if we can only payout as many sats as we paid for the market,
// we need to solve for b: b = cost / ln2
b = (float64(cost) / 1000) / math.Log(2)
expiry = int64(600)
expiresAt = time.Now().Add(time.Second * time.Duration(expiry))
invoiceId int
marketId int
invDescription string
qr templ.Component
err error
)
// TODO: validation
if tx, err = db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelReadCommitted}); err != nil {
return err
}
if hash, paymentRequest, err = lnd.Client.AddInvoice(ctx,
&invoicesrpc.AddInvoiceData{
Value: cost,
Expiry: expiry,
}); err != nil {
return err
}
if err = tx.QueryRowContext(ctx, ""+
"INSERT INTO invoices (user_id, msats, hash, bolt11, expires_at) "+
"VALUES ($1, $2, $3, $4, $5) "+
"RETURNING id",
u.Id, cost, hash.String(), paymentRequest, expiresAt).Scan(&invoiceId); err != nil {
return err
}
if err = tx.QueryRowContext(ctx, ""+
"INSERT INTO markets (question, description, end_date, user_id, invoice_id, lmsr_b) "+
"VALUES ($1, $2, $3, $4, $5, $6) "+
"RETURNING id",
question, description, endDate, u.Id, invoiceId, b).Scan(&marketId); err != nil {
return err
}
invDescription = fmt.Sprintf("create market %d", marketId)
if _, err = tx.ExecContext(ctx, ""+
"UPDATE invoices SET description = $1 WHERE id = $2",
invDescription, invoiceId); err != nil {
return err
}
if err = tx.Commit(); err != nil {
return err
}
qr = components.Invoice(hash.String(), paymentRequest, int(cost), int(expiry), false, toRedirectUrl(invDescription))
return components.Modal(qr).Render(context.RenderContext(sc, c), c.Response().Writer)
}
}
func HandleMarket(sc context.Context) echo.HandlerFunc {
return func(c echo.Context) error {
var (
db = sc.Db
ctx = c.Request().Context()
u = types.User{}
id = c.Param("id")
quantity = c.QueryParam("q")
q int64
m = types.Market{}
mU = types.User{}
l = types.LMSR{}
total float64
quote0 = types.MarketQuote{}
quote1 = types.MarketQuote{}
uQ0 int
uQ1 int
err error
)
if c.Get("session") != nil {
u = c.Get("session").(types.User)
} else {
u.Id = -1
}
if quantity == "" {
q = 1
} else if q, err = strconv.ParseInt(quantity, 10, 64); err != nil {
return echo.NewHTTPError(http.StatusBadRequest, "q must be integer")
}
if err = db.QueryRowContext(ctx, ""+
"SELECT m.id, m.question, m.description, m.created_at, m.end_date, m.lmsr_b, "+
"u.id, u.name, u.created_at, u.ln_pubkey, u.nostr_pubkey, u.msats "+
"FROM markets m "+
"JOIN users u ON m.user_id = u.id "+
"JOIN invoices i ON m.invoice_id = i.id "+
"WHERE m.id = $1 AND i.confirmed_at IS NOT NULL", id).Scan(
&m.Id, &m.Question, &m.Description, &m.CreatedAt, &m.EndDate, &l.B,
&mU.Id, &mU.Name, &mU.CreatedAt, &mU.LnPubkey, &mU.NostrPubkey, &mU.Msats); err != nil {
if err == sql.ErrNoRows {
return echo.NewHTTPError(http.StatusNotFound)
}
return err
}
m.User = mU
if err = db.QueryRowContext(ctx, ""+
"SELECT "+
"COALESCE(SUM(o.quantity) FILTER(WHERE o.outcome = 0), 0) AS q1, "+
"COALESCE(SUM(o.quantity) FILTER(WHERE o.outcome = 1), 0) AS q2, "+
"COALESCE(SUM(o.quantity) FILTER(WHERE o.outcome = 0 AND o.user_id = $2), 0) AS uq1, "+
"COALESCE(SUM(o.quantity) FILTER(WHERE o.outcome = 1 AND o.user_id = $2), 0) AS uq2 "+
"FROM orders o "+
"JOIN markets m ON o.market_id = m.id "+
"JOIN invoices i ON o.invoice_id = i.id "+
// QUESTION: Should unpaid orders contribute to quantity or not?
//
// The answer is relevant for concurrent orders:
// If they do, one can artificially increase the price for others
// by creating a lot of pending orders.
// If they don't, one can buy infinite amount of shares at the same price
// by creating a lot of small but concurrent orders.
// I think this means that pending order must be scoped to a user
// but this isn't sybil resistant.
//
// For now, we will ignore pending orders.
"WHERE o.market_id = $1 AND i.confirmed_at IS NOT NULL", id, u.Id).Scan(
&l.Q1, &l.Q2, &uQ0, &uQ1); err != nil {
if err == sql.ErrNoRows {
return echo.NewHTTPError(http.StatusNotFound)
}
return err
}
total = lmsr.Quote(l.B, l.Q1, l.Q2, int(q))
quote0 = types.MarketQuote{
Outcome: 0,
AvgPrice: total / float64(q),
TotalPrice: total,
Reward: float64(q) - total,
}
total = lmsr.Quote(l.B, l.Q2, l.Q1, int(q))
quote1 = types.MarketQuote{
Outcome: 1,
AvgPrice: total / float64(q),
TotalPrice: total,
Reward: float64(q) - total,
}
return pages.Market(m, quote0, quote1, uQ0, uQ1).Render(context.RenderContext(sc, c), c.Response().Writer)
}
}
func HandleOrder(sc context.Context) echo.HandlerFunc {
return func(c echo.Context) error {
var (
db = sc.Db
lnd = sc.Lnd
tx *sql.Tx
ctx = c.Request().Context()
u = c.Get("session").(types.User)
id = c.Param("id")
quantity = c.FormValue("q")
outcome = c.FormValue("o")
q int64
o int64
m = types.Market{}
mU = types.User{}
l = types.LMSR{}
totalF float64
total int
hash lntypes.Hash
paymentRequest string
expiry = int64(60)
expiresAt = time.Now().Add(time.Second * time.Duration(expiry))
invoiceId int
invDescription string
orderId int
qr templ.Component
err error
)
if quantity == "" {
return echo.NewHTTPError(http.StatusBadRequest, "q must be given")
} else if q, err = strconv.ParseInt(quantity, 10, 64); err != nil {
return echo.NewHTTPError(http.StatusBadRequest, "q must be integer")
}
if outcome == "" {
return echo.NewHTTPError(http.StatusBadRequest, "o must be given")
} else if o, err = strconv.ParseInt(outcome, 10, 64); err != nil {
return echo.NewHTTPError(http.StatusBadRequest, "o must be integer")
}
if o < 0 && o > 1 {
return echo.NewHTTPError(http.StatusBadRequest, "o must be 0 or 1")
}
// TODO: refactor since this uses same queries as function above
if err = db.QueryRowContext(ctx, ""+
"SELECT m.id, m.question, m.description, m.created_at, m.end_date, m.lmsr_b, "+
"u.id, u.name, u.created_at, u.ln_pubkey, u.nostr_pubkey, u.msats "+
"FROM markets m "+
"JOIN users u ON m.user_id = u.id "+
"JOIN invoices i ON m.invoice_id = i.id "+
"WHERE m.id = $1 AND i.confirmed_at IS NOT NULL", id).Scan(
&m.Id, &m.Question, &m.Description, &m.CreatedAt, &m.EndDate, &l.B,
&mU.Id, &mU.Name, &mU.CreatedAt, &mU.LnPubkey, &mU.NostrPubkey, &mU.Msats); err != nil {
if err == sql.ErrNoRows {
return echo.NewHTTPError(http.StatusNotFound)
}
return err
}
m.User = mU
if err = db.QueryRowContext(ctx, ""+
"SELECT "+
"COALESCE(SUM(o.quantity) FILTER(WHERE o.outcome = 0), 0) AS q1, "+
"COALESCE(SUM(o.quantity) FILTER(WHERE o.outcome = 1), 0) AS q2 "+
"FROM orders o "+
"JOIN markets m ON o.market_id = m.id "+
"JOIN invoices i ON o.invoice_id = i.id "+
"WHERE o.market_id = $1 AND i.confirmed_at IS NOT NULL", id).Scan(
&l.Q1, &l.Q2); err != nil {
if err == sql.ErrNoRows {
return echo.NewHTTPError(http.StatusNotFound)
}
return err
}
if o == 0 {
totalF = lmsr.Quote(l.B, l.Q1, l.Q2, int(q))
} else if o == 1 {
totalF = lmsr.Quote(l.B, l.Q2, l.Q1, int(q))
}
total = int(math.Round(totalF * 1000))
if tx, err = db.BeginTx(ctx, &sql.TxOptions{Isolation: sql.LevelReadCommitted}); err != nil {
return err
}
if hash, paymentRequest, err = lnd.Client.AddInvoice(ctx,
&invoicesrpc.AddInvoiceData{
Value: lnwire.MilliSatoshi(total),
Expiry: expiry,
}); err != nil {
return err
}
if err = tx.QueryRowContext(ctx, ""+
"INSERT INTO invoices (user_id, msats, hash, bolt11, expires_at) "+
"VALUES ($1, $2, $3, $4, $5) "+
"RETURNING id",
u.Id, total, hash.String(), paymentRequest, expiresAt).Scan(&invoiceId); err != nil {
return err
}
if err = tx.QueryRowContext(ctx, ""+
"INSERT INTO orders (market_id, user_id, quantity, outcome, invoice_id) "+
"VALUES ($1, $2, $3, $4, $5) "+
"RETURNING id",
id, u.Id, q, o, invoiceId).Scan(&orderId); err != nil {
return err
}
invDescription = fmt.Sprintf("create order %d for market %s", orderId, id)
if _, err = tx.ExecContext(ctx, ""+
"UPDATE invoices SET description = $1 WHERE id = $2",
invDescription, invoiceId); err != nil {
return err
}
if err = tx.Commit(); err != nil {
return err
}
qr = components.Invoice(hash.String(), paymentRequest, total, int(expiry), false, toRedirectUrl(invDescription))
return components.Modal(qr).Render(context.RenderContext(sc, c), c.Response().Writer)
}
}