manifold/functions/src/place-bet.ts
Marshall Polaris 6956f0d730
Implement really obvious optimizations on placebet, sellbet, sellshares (#452)
* Change authed endpoints to not look up users unnecessarily

* Parallelize some extremely parallelizable DB requests

* Clean up overcomplicated sellshares logic
2022-06-10 17:51:55 -07:00

120 lines
3.9 KiB
TypeScript

import * as admin from 'firebase-admin'
import { z } from 'zod'
import { APIError, newEndpoint, validate } from './api'
import { Contract, CPMM_MIN_POOL_QTY } from '../../common/contract'
import { User } from '../../common/user'
import {
BetInfo,
getNewBinaryCpmmBetInfo,
getNewBinaryDpmBetInfo,
getNewMultiBetInfo,
getNumericBetsInfo,
} from '../../common/new-bet'
import { addObjects, removeUndefinedProps } from '../../common/util/object'
import { redeemShares } from './redeem-shares'
const bodySchema = z.object({
contractId: z.string(),
amount: z.number().gte(1),
})
const binarySchema = z.object({
outcome: z.enum(['YES', 'NO']),
})
const freeResponseSchema = z.object({
outcome: z.string(),
})
const numericSchema = z.object({
outcome: z.string(),
value: z.number(),
})
export const placebet = newEndpoint(['POST'], async (req, auth) => {
const { amount, contractId } = validate(bodySchema, req.body)
const result = await firestore.runTransaction(async (trans) => {
const contractDoc = firestore.doc(`contracts/${contractId}`)
const userDoc = firestore.doc(`users/${auth.uid}`)
const [contractSnap, userSnap] = await Promise.all([
trans.get(contractDoc),
trans.get(userDoc),
])
if (!contractSnap.exists) throw new APIError(400, 'Contract not found.')
if (!userSnap.exists) throw new APIError(400, 'User not found.')
const contract = contractSnap.data() as Contract
const user = userSnap.data() as User
if (user.balance < amount) throw new APIError(400, 'Insufficient balance.')
const loanAmount = 0
const { closeTime, outcomeType, mechanism, collectedFees, volume } =
contract
if (closeTime && Date.now() > closeTime)
throw new APIError(400, 'Trading is closed.')
const {
newBet,
newPool,
newTotalShares,
newTotalBets,
newTotalLiquidity,
newP,
} = await (async (): Promise<BetInfo> => {
if (outcomeType == 'BINARY' && mechanism == 'dpm-2') {
const { outcome } = validate(binarySchema, req.body)
return getNewBinaryDpmBetInfo(outcome, amount, contract, loanAmount)
} else if (outcomeType == 'BINARY' && mechanism == 'cpmm-1') {
const { outcome } = validate(binarySchema, req.body)
return getNewBinaryCpmmBetInfo(outcome, amount, contract, loanAmount)
} else if (outcomeType == 'FREE_RESPONSE' && mechanism == 'dpm-2') {
const { outcome } = validate(freeResponseSchema, req.body)
const answerDoc = contractDoc.collection('answers').doc(outcome)
const answerSnap = await trans.get(answerDoc)
if (!answerSnap.exists) throw new APIError(400, 'Invalid answer')
return getNewMultiBetInfo(outcome, amount, contract, loanAmount)
} else if (outcomeType == 'NUMERIC' && mechanism == 'dpm-2') {
const { outcome, value } = validate(numericSchema, req.body)
return getNumericBetsInfo(value, outcome, amount, contract)
} else {
throw new APIError(500, 'Contract has invalid type/mechanism.')
}
})()
if (
mechanism == 'cpmm-1' &&
(!newP ||
!isFinite(newP) ||
Math.min(...Object.values(newPool ?? {})) < CPMM_MIN_POOL_QTY)
) {
throw new APIError(400, 'Bet too large for current liquidity pool.')
}
const newBalance = user.balance - amount - loanAmount
const betDoc = contractDoc.collection('bets').doc()
trans.create(betDoc, { id: betDoc.id, userId: user.id, ...newBet })
trans.update(userDoc, { balance: newBalance })
trans.update(
contractDoc,
removeUndefinedProps({
pool: newPool,
p: newP,
totalShares: newTotalShares,
totalBets: newTotalBets,
totalLiquidity: newTotalLiquidity,
collectedFees: addObjects(newBet.fees, collectedFees),
volume: volume + amount,
})
)
return { betId: betDoc.id }
})
await redeemShares(auth.uid, contractId)
return result
})
const firestore = admin.firestore()