Query hot contracts from volume24Hours field.

web/hooks/use-contracts.ts

@@ -1,10 +1,9 @@
 import _ from 'lodash'
 import { useEffect, useState } from 'react'
-import { Bet, listenForRecentBets } from '../lib/firebase/bets'
 import {
-  computeHotContracts,
   Contract,
   listenForContracts,
+  listenForHotContracts,
 } from '../lib/firebase/contracts'
 
 export const useContracts = () => {
@@ -18,14 +17,9 @@ export const useContracts = () => {
 }
 
 export const useHotContracts = () => {
-  const [recentBets, setRecentBets] = useState<Bet[] | 'loading'>('loading')
+  const [hotContracts, setHotContracts] = useState<Contract[] | undefined>()
 
-  useEffect(() => {
-    const oneDay = 1000 * 60 * 60 * 24
-    return listenForRecentBets(oneDay, setRecentBets)
-  }, [])
+  useEffect(() => listenForHotContracts(setHotContracts), [])
 
-  if (recentBets === 'loading') return 'loading'
-
-  return computeHotContracts(recentBets)
+  return hotContracts
 }

web/lib/firebase/bets.ts

@@ -4,7 +4,6 @@ import {
   query,
   onSnapshot,
   where,
-  getDocs,
 } from 'firebase/firestore'
 import _ from 'lodash'
 import { db } from './init'
@@ -64,34 +63,3 @@ export function listenForUserBets(
     setBets(bets)
   })
 }
-
-export function listenForRecentBets(
-  timePeriodMs: number,
-  setBets: (bets: Bet[]) => void
-) {
-  const recentQuery = query(
-    collectionGroup(db, 'bets'),
-    where('createdTime', '>', Date.now() - timePeriodMs)
-  )
-  return onSnapshot(recentQuery, (snap) => {
-    const bets = snap.docs.map((doc) => doc.data() as Bet)
-
-    bets.sort((bet1, bet2) => bet1.createdTime - bet2.createdTime)
-
-    setBets(bets)
-  })
-}
-
-export async function getRecentBets(timePeriodMs: number) {
-  const recentQuery = query(
-    collectionGroup(db, 'bets'),
-    where('createdTime', '>', Date.now() - timePeriodMs)
-  )
-
-  const snapshot = await getDocs(recentQuery)
-  const bets = snapshot.docs.map((doc) => doc.data() as Bet)
-
-  bets.sort((bet1, bet2) => bet1.createdTime - bet2.createdTime)
-
-  return bets
-}

web/lib/firebase/contracts.ts

@@ -12,10 +12,10 @@ import {
   orderBy,
   getDoc,
   updateDoc,
+  limit,
 } from 'firebase/firestore'
 import dayjs from 'dayjs'
-import { Bet, getRecentBets } from './bets'
-import _ from 'lodash'
+import { getValues, listenForValues } from './utils'
 
 export type Contract = {
   id: string
@@ -145,16 +145,19 @@ export function listenForContract(
   })
 }
 
-export function computeHotContracts(recentBets: Bet[]) {
-  const contractBets = _.groupBy(recentBets, (bet) => bet.contractId)
-  const hotContractIds = _.sortBy(Object.keys(contractBets), (contractId) =>
-    _.sumBy(contractBets[contractId], (bet) => -1 * bet.amount)
+const hotContractsQuery = query(
+  contractCollection,
+  where('isResolved', '==', false),
+  orderBy('volume24Hours', 'desc'),
+  limit(4)
 )
-  return hotContractIds
+
+export function listenForHotContracts(
+  setHotContracts: (contracts: Contract[]) => void
+) {
+  return listenForValues<Contract>(hotContractsQuery, setHotContracts)
 }
 
-export async function getHotContracts() {
-  const oneDay = 1000 * 60 * 60 * 24
-  const recentBets = await getRecentBets(oneDay)
-  return computeHotContracts(recentBets)
+export function getHotContracts() {
+  return getValues<Contract>(hotContractsQuery)
 }

web/lib/firebase/utils.ts

@@ -0,0 +1,39 @@
+import { db } from './init'
+import {
+  doc,
+  getDoc,
+  getDocs,
+  onSnapshot,
+  Query,
+  DocumentReference,
+} from 'firebase/firestore'
+
+export const getValue = async <T>(collectionName: string, docName: string) => {
+  const snap = await getDoc(doc(db, collectionName, docName))
+  return snap.exists() ? (snap.data() as T) : null
+}
+
+export const getValues = async <T>(query: Query) => {
+  const snap = await getDocs(query)
+  return snap.docs.map((doc) => doc.data() as T)
+}
+
+export function listenForValue<T>(
+  docRef: DocumentReference,
+  setValue: (value: T | null) => void
+) {
+  return onSnapshot(docRef, (snapshot) => {
+    const value = snapshot.exists() ? (snapshot.data() as T) : null
+    setValue(value)
+  })
+}
+
+export function listenForValues<T>(
+  query: Query,
+  setValues: (values: T[]) => void
+) {
+  return onSnapshot(query, (snapshot) => {
+    const values = snapshot.docs.map((doc) => doc.data() as T)
+    setValues(values)
+  })
+}

web/pages/index.tsx

@@ -1,5 +1,5 @@
 import React from 'react'
-
+import _ from 'lodash'
 import { useUser } from '../hooks/use-user'
 import Markets from './markets'
 import LandingPage from './landing-page'
@@ -8,10 +8,9 @@ import {
   getHotContracts,
   listAllContracts,
 } from '../lib/firebase/contracts'
-import _ from 'lodash'
 
 export async function getStaticProps() {
-  const [contracts, hotContractIds] = await Promise.all([
+  const [contracts, hotContracts] = await Promise.all([
     listAllContracts().catch((_) => []),
     getHotContracts().catch(() => []),
   ])
@@ -19,26 +18,22 @@ export async function getStaticProps() {
   return {
     props: {
       contracts,
-      hotContractIds,
+      hotContracts,
     },
 
     revalidate: 60, // regenerate after a minute
   }
 }
 
-const Home = (props: { contracts: Contract[]; hotContractIds: string[] }) => {
+const Home = (props: { contracts: Contract[]; hotContracts: Contract[] }) => {
   const user = useUser()
 
   if (user === undefined) return <></>
 
-  const { contracts, hotContractIds } = props
-  const hotContracts = hotContractIds
-    .map((id) => contracts.find((contract) => contract.id === id) as Contract)
-    .filter((contract) => !contract.isResolved)
-    .slice(0, 4)
+  const { contracts, hotContracts } = props
 
   return user ? (
-    <Markets contracts={contracts} hotContractIds={hotContractIds} />
+    <Markets contracts={contracts} hotContracts={hotContracts} />
   ) : (
     <LandingPage hotContracts={hotContracts} />
   )

web/pages/markets.tsx

@@ -12,7 +12,7 @@ import {
 } from '../lib/firebase/contracts'
 
 export async function getStaticProps() {
-  const [contracts, hotContractIds] = await Promise.all([
+  const [contracts, hotContracts] = await Promise.all([
     listAllContracts().catch((_) => []),
     getHotContracts().catch(() => []),
   ])
@@ -20,7 +20,7 @@ export async function getStaticProps() {
   return {
     props: {
       contracts,
-      hotContractIds,
+      hotContracts,
     },
 
     revalidate: 60, // regenerate after a minute
@@ -29,29 +29,20 @@ export async function getStaticProps() {
 
 export default function Markets(props: {
   contracts: Contract[]
-  hotContractIds: string[]
+  hotContracts: Contract[]
 }) {
   const contracts = useContracts()
+  const hotContracts = useHotContracts()
   const { query, setQuery, sort, setSort } = useQueryAndSortParams()
-  const hotContractIds = useHotContracts()
 
-  const readyHotContractIds =
-    hotContractIds === 'loading' ? props.hotContractIds : hotContractIds
+  const readyHotContracts = hotContracts ?? props.hotContracts
   const readyContracts = contracts === 'loading' ? props.contracts : contracts
 
-  const hotContracts = readyHotContractIds
-    .map(
-      (hotId) =>
-        _.find(readyContracts, (contract) => contract.id === hotId) as Contract
-    )
-    .filter((contract) => !contract.isResolved)
-    .slice(0, 4)
-
   return (
     <Page>
       <div className="w-full bg-indigo-50 border-2 border-indigo-100 p-6 rounded-lg shadow-md">
         <Title className="mt-0" text="🔥 Markets" />
-        <ContractsGrid contracts={hotContracts} />
+        <ContractsGrid contracts={readyHotContracts} />
       </div>
 
       <Spacer h={10} />