Migrate sellShares cloud function to v2 sellshares (#440)

* Migrate `sellShares` to v2 `sellshares`

* Point client at new v2 sellshares function

* Clean up `getCpmmSellBetInfo`

common/envs/dev.ts

@@ -14,6 +14,7 @@ export const DEV_CONFIG: EnvConfig = {
   },
   functionEndpoints: {
     placebet: 'https://placebet-w3txbmd3ba-uc.a.run.app',
+    sellshares: 'https://sellshares-w3txbmd3ba-uc.a.run.app',
     createmarket: 'https://createmarket-w3txbmd3ba-uc.a.run.app',
   },
 }

common/envs/prod.ts

@@ -1,4 +1,4 @@
-export type V2CloudFunction = 'placebet' | 'createmarket'
+export type V2CloudFunction = 'placebet' | 'sellshares' | 'createmarket'
 
 export type EnvConfig = {
   domain: string
@@ -42,6 +42,7 @@ export const PROD_CONFIG: EnvConfig = {
   },
   functionEndpoints: {
     placebet: 'https://placebet-nggbo3neva-uc.a.run.app',
+    sellshares: 'https://sellshares-nggbo3neva-uc.a.run.app',
     createmarket: 'https://createmarket-nggbo3neva-uc.a.run.app',
   },
   adminEmails: [

common/envs/theoremone.ts

@@ -15,6 +15,7 @@ export const THEOREMONE_CONFIG: EnvConfig = {
   // TODO: fill in real endpoints for T1
   functionEndpoints: {
     placebet: 'https://placebet-nggbo3neva-uc.a.run.app',
+    sellshares: 'https://sellshares-nggbo3neva-uc.a.run.app',
     createmarket: 'https://createmarket-nggbo3neva-uc.a.run.app',
   },
   adminEmails: [...PROD_CONFIG.adminEmails, 'david.glidden@theoremone.co'],

common/sell-bet.ts

@@ -9,6 +9,8 @@ import { CPMMContract, DPMContract } from './contract'
 import { DPM_CREATOR_FEE, DPM_PLATFORM_FEE, Fees } from './fees'
 import { User } from './user'
 
+export type CandidateBet<T extends Bet> = Omit<T, 'id' | 'userId'>
+
 export const getSellBetInfo = (
   user: User,
   bet: Bet,
@@ -84,12 +86,10 @@ export const getSellBetInfo = (
 }
 
 export const getCpmmSellBetInfo = (
-  user: User,
   shares: number,
   outcome: 'YES' | 'NO',
   contract: CPMMContract,
-  prevLoanAmount: number,
-  newBetId: string
+  prevLoanAmount: number
 ) => {
   const { pool, p } = contract
 
@@ -100,8 +100,6 @@ export const getCpmmSellBetInfo = (
   )
 
   const loanPaid = Math.min(prevLoanAmount, saleValue)
-  const netAmount = saleValue - loanPaid
-
   const probBefore = getCpmmProbability(pool, p)
   const probAfter = getCpmmProbability(newPool, p)
 
@@ -115,9 +113,7 @@ export const getCpmmSellBetInfo = (
     fees.creatorFee
   )
 
-  const newBet: Bet = {
-    id: newBetId,
-    userId: user.id,
+  const newBet: CandidateBet<Bet> = {
     contractId: contract.id,
     amount: -saleValue,
     shares: -shares,
@@ -129,13 +125,10 @@ export const getCpmmSellBetInfo = (
     fees,
   }
 
-  const newBalance = user.balance + netAmount
-
   return {
     newBet,
     newPool,
     newP,
-    newBalance,
     fees,
   }
 }

functions/src/sell-shares.ts

@@ -1,114 +1,90 @@
 import { partition, sumBy } from 'lodash'
 import * as admin from 'firebase-admin'
-import * as functions from 'firebase-functions'
+import { z } from 'zod'
 
-import { BinaryContract } from '../../common/contract'
+import { APIError, newEndpoint, validate } from './api'
+import { Contract } from '../../common/contract'
 import { User } from '../../common/user'
 import { getCpmmSellBetInfo } from '../../common/sell-bet'
 import { addObjects, removeUndefinedProps } from '../../common/util/object'
 import { getValues } from './utils'
 import { Bet } from '../../common/bet'
 
-export const sellShares = functions.runWith({ minInstances: 1 }).https.onCall(
-  async (
-    data: {
-      contractId: string
-      shares: number
-      outcome: 'YES' | 'NO'
-    },
-    context
-  ) => {
-    const userId = context?.auth?.uid
-    if (!userId) return { status: 'error', message: 'Not authorized' }
+const bodySchema = z.object({
+  contractId: z.string(),
+  shares: z.number(),
+  outcome: z.enum(['YES', 'NO']),
+})
 
-    const { contractId, shares, outcome } = data
+export const sellshares = newEndpoint(['POST'], async (req, [bettor, _]) => {
+  const { contractId, shares, outcome } = validate(bodySchema, req.body)
 
-    // Run as transaction to prevent race conditions.
-    return await firestore.runTransaction(async (transaction) => {
-      const userDoc = firestore.doc(`users/${userId}`)
-      const userSnap = await transaction.get(userDoc)
-      if (!userSnap.exists)
-        return { status: 'error', message: 'User not found' }
-      const user = userSnap.data() as User
+  // Run as transaction to prevent race conditions.
+  return await firestore.runTransaction(async (transaction) => {
+    const userDoc = firestore.doc(`users/${bettor.id}`)
+    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/${contractId}`)
-      const contractSnap = await transaction.get(contractDoc)
-      if (!contractSnap.exists)
-        return { status: 'error', message: 'Invalid contract' }
-      const contract = contractSnap.data() as BinaryContract
-      const { closeTime, mechanism, collectedFees, volume } = contract
+    const contractDoc = firestore.doc(`contracts/${contractId}`)
+    const contractSnap = await transaction.get(contractDoc)
+    if (!contractSnap.exists) throw new APIError(400, 'Contract not found.')
+    const contract = contractSnap.data() as Contract
+    const { closeTime, mechanism, collectedFees, volume } = contract
 
-      if (mechanism !== 'cpmm-1')
-        return {
-          status: 'error',
-          message: 'Sell shares only works with mechanism cpmm-1',
-        }
+    if (mechanism !== 'cpmm-1')
+      throw new APIError(400, 'You can only sell shares on CPMM-1 contracts.')
+    if (closeTime && Date.now() > closeTime)
+      throw new APIError(400, 'Trading is closed.')
 
-      if (closeTime && Date.now() > closeTime)
-        return { status: 'error', message: 'Trading is closed' }
+    const userBets = await getValues<Bet>(
+      contractDoc.collection('bets').where('userId', '==', bettor.id)
+    )
 
-      const userBets = await getValues<Bet>(
-        contractDoc.collection('bets').where('userId', '==', userId)
-      )
+    const prevLoanAmount = sumBy(userBets, (bet) => bet.loanAmount ?? 0)
 
-      const prevLoanAmount = sumBy(userBets, (bet) => bet.loanAmount ?? 0)
+    const [yesBets, noBets] = partition(
+      userBets ?? [],
+      (bet) => bet.outcome === 'YES'
+    )
+    const [yesShares, noShares] = [
+      sumBy(yesBets, (bet) => bet.shares),
+      sumBy(noBets, (bet) => bet.shares),
+    ]
 
-      const [yesBets, noBets] = partition(
-        userBets ?? [],
-        (bet) => bet.outcome === 'YES'
-      )
-      const [yesShares, noShares] = [
-        sumBy(yesBets, (bet) => bet.shares),
-        sumBy(noBets, (bet) => bet.shares),
-      ]
+    const maxShares = outcome === 'YES' ? yesShares : noShares
+    if (shares > maxShares + 0.000000000001)
+      throw new APIError(400, `You can only sell up to ${maxShares} shares.`)
 
-      const maxShares = outcome === 'YES' ? yesShares : noShares
-      if (shares > maxShares + 0.000000000001) {
-        return {
-          status: 'error',
-          message: `You can only sell ${maxShares} shares`,
-        }
-      }
+    const { newBet, newPool, newP, fees } = getCpmmSellBetInfo(
+      shares,
+      outcome,
+      contract,
+      prevLoanAmount
+    )
 
-      const newBetDoc = firestore
-        .collection(`contracts/${contractId}/bets`)
-        .doc()
+    if (!isFinite(newP)) {
+      throw new APIError(500, 'Trade rejected due to overflow error.')
+    }
 
-      const { newBet, newPool, newP, newBalance, fees } = getCpmmSellBetInfo(
-        user,
-        shares,
-        outcome,
-        contract,
-        prevLoanAmount,
-        newBetDoc.id
-      )
+    const newBetDoc = firestore.collection(`contracts/${contractId}/bets`).doc()
+    const newBalance = user.balance - newBet.amount + (newBet.loanAmount ?? 0)
+    const userId = user.id
 
-      if (!isFinite(newP)) {
-        return {
-          status: 'error',
-          message: 'Trade rejected due to overflow error.',
-        }
-      }
+    transaction.update(userDoc, { balance: newBalance })
+    transaction.create(newBetDoc, { id: newBetDoc.id, userId, ...newBet })
+    transaction.update(
+      contractDoc,
+      removeUndefinedProps({
+        pool: newPool,
+        p: newP,
+        collectedFees: addObjects(fees, collectedFees),
+        volume: volume + Math.abs(newBet.amount),
+      })
+    )
 
-      if (!isFinite(newBalance)) {
-        throw new Error('Invalid user balance for ' + user.username)
-      }
-
-      transaction.update(userDoc, { balance: newBalance })
-      transaction.create(newBetDoc, newBet)
-      transaction.update(
-        contractDoc,
-        removeUndefinedProps({
-          pool: newPool,
-          p: newP,
-          collectedFees: addObjects(fees, collectedFees),
-          volume: volume + Math.abs(newBet.amount),
-        })
-      )
-
-      return { status: 'success' }
-    })
-  }
-)
+    return { status: 'success' }
+  })
+})
 
 const firestore = admin.firestore()

web/components/bet-panel.tsx

@@ -17,7 +17,7 @@ import { Title } from './title'
 import { User } from 'web/lib/firebase/users'
 import { Bet } from 'common/bet'
 import { APIError, placeBet } from 'web/lib/firebase/api-call'
-import { sellShares } from 'web/lib/firebase/fn-call'
+import { sellShares } from 'web/lib/firebase/api-call'
 import { AmountInput, BuyAmountInput } from './amount-input'
 import { InfoTooltip } from './info-tooltip'
 import { BinaryOutcomeLabel } from './outcome-label'
@@ -398,23 +398,27 @@ export function SellPanel(props: {
     // Sell all shares if remaining shares would be < 1
     const sellAmount = amount === Math.floor(shares) ? shares : amount
 
-    const result = await sellShares({
+    await sellShares({
       shares: sellAmount,
       outcome: sharesOutcome,
       contractId: contract.id,
-    }).then((r) => r.data)
-
-    console.log('Sold shares. Result:', result)
-
-    if (result?.status === 'success') {
-      setIsSubmitting(false)
-      setWasSubmitted(true)
-      setAmount(undefined)
-      if (onSellSuccess) onSellSuccess()
-    } else {
-      setError(result?.message || 'Error selling')
-      setIsSubmitting(false)
-    }
+    })
+      .then((r) => {
+        console.log('Sold shares. Result:', r)
+        setIsSubmitting(false)
+        setWasSubmitted(true)
+        setAmount(undefined)
+        if (onSellSuccess) onSellSuccess()
+      })
+      .catch((e) => {
+        if (e instanceof APIError) {
+          setError(e.toString())
+        } else {
+          console.error(e)
+          setError('Error selling')
+        }
+        setIsSubmitting(false)
+      })
   }
 
   const initialProb = getProbability(contract)

web/components/contract/quick-bet.tsx

@@ -22,7 +22,7 @@ import TriangleFillIcon from 'web/lib/icons/triangle-fill-icon'
 import { Col } from '../layout/col'
 import { OUTCOME_TO_COLOR } from '../outcome-label'
 import { useSaveShares } from '../use-save-shares'
-import { sellShares } from 'web/lib/firebase/fn-call'
+import { sellShares } from 'web/lib/firebase/api-call'
 import { calculateCpmmSale, getCpmmProbability } from 'common/calculate-cpmm'
 
 const BET_SIZE = 10

web/lib/firebase/api-call.ts

@@ -50,3 +50,7 @@ export function createMarket(params: any) {
 export function placeBet(params: any) {
   return call(getFunctionUrl('placebet'), 'POST', params)
 }
+
+export function sellShares(params: any) {
+  return call(getFunctionUrl('sellshares'), 'POST', params)
+}

web/lib/firebase/fn-call.ts

@@ -22,11 +22,6 @@ export const transact = cloudFunction<
 
 export const sellBet = cloudFunction('sellBet')
 
-export const sellShares = cloudFunction<
-  { contractId: string; shares: number; outcome: 'YES' | 'NO' },
-  { status: 'error' | 'success'; message?: string }
->('sellShares')
-
 export const createAnswer = cloudFunction<
   { contractId: string; text: string; amount: number },
   {