manifold/functions/src/add-liquidity.ts

91 lines
2.7 KiB
TypeScript

import * as admin from 'firebase-admin'
import { z } from 'zod'
import { Contract } from '../../common/contract'
import { User } from '../../common/user'
import { removeUndefinedProps } from '../../common/util/object'
import { getNewLiquidityProvision } from '../../common/add-liquidity'
import { APIError, newEndpoint, validate } from './api'
const bodySchema = z.object({
contractId: z.string(),
amount: z.number().gt(0),
})
export const addliquidity = newEndpoint({}, async (req, auth) => {
const { amount, contractId } = validate(bodySchema, req.body)
if (!isFinite(amount)) throw new APIError(400, 'Invalid amount')
// run as transaction to prevent race conditions
return await firestore.runTransaction(async (transaction) => {
const userDoc = firestore.doc(`users/${auth.uid}`)
const userSnap = await transaction.get(userDoc)
if (!userSnap.exists) throw new APIError(400, 'User not found')
const user = userSnap.data() as User
const contractDoc = firestore.doc(`contracts/${contractId}`)
const contractSnap = await transaction.get(contractDoc)
if (!contractSnap.exists) throw new APIError(400, 'Invalid contract')
const contract = contractSnap.data() as Contract
if (
contract.mechanism !== 'cpmm-1' ||
(contract.outcomeType !== 'BINARY' &&
contract.outcomeType !== 'PSEUDO_NUMERIC')
)
throw new APIError(400, 'Invalid contract')
const { closeTime } = contract
if (closeTime && Date.now() > closeTime)
throw new APIError(400, 'Trading is closed')
if (user.balance < amount) throw new APIError(400, 'Insufficient balance')
const newLiquidityProvisionDoc = firestore
.collection(`contracts/${contractId}/liquidity`)
.doc()
const { newLiquidityProvision, newPool, newP, newTotalLiquidity } =
getNewLiquidityProvision(
user,
amount,
contract,
newLiquidityProvisionDoc.id
)
if (newP !== undefined && !isFinite(newP)) {
return {
status: 'error',
message: 'Liquidity injection rejected due to overflow error.',
}
}
transaction.update(
contractDoc,
removeUndefinedProps({
pool: newPool,
p: newP,
totalLiquidity: newTotalLiquidity,
})
)
const newBalance = user.balance - amount
const newTotalDeposits = user.totalDeposits - amount
if (!isFinite(newBalance)) {
throw new APIError(500, 'Invalid user balance for ' + user.username)
}
transaction.update(userDoc, {
balance: newBalance,
totalDeposits: newTotalDeposits,
})
transaction.create(newLiquidityProvisionDoc, newLiquidityProvision)
return newLiquidityProvision
})
})
const firestore = admin.firestore()