From 0b283aad9cf7346483cb1f419f98f480e1b1ffb6 Mon Sep 17 00:00:00 2001
From: Dong-Ha Kim <dongha.kim210@gmail.com>
Date: Thu, 12 Sep 2024 01:06:55 +0700
Subject: [PATCH] feat: cron job cache relayer balances

---
 api/_cache.ts              | 19 ++++++++++-
 api/_utils.ts              | 37 ++++++++------------
 api/cron-cache-balances.ts | 69 ++++++++++++++++++++++++++++++++++++++
 vercel.json                |  6 ++++
 4 files changed, 107 insertions(+), 24 deletions(-)
 create mode 100644 api/cron-cache-balances.ts

diff --git a/api/_cache.ts b/api/_cache.ts
index b170042e3..5f6391034 100644
--- a/api/_cache.ts
+++ b/api/_cache.ts
@@ -66,7 +66,7 @@ export async function getCachedValue<T>(
   ttl: number,
   fetcher: () => Promise<T>,
   parser?: (value: T) => T
-) {
+): Promise<T> {
   const cachedValue = await redisCache.get<T>(key);
   if (cachedValue) {
     return parser ? parser(cachedValue) : cachedValue;
@@ -76,3 +76,20 @@ export async function getCachedValue<T>(
   await redisCache.set(key, value, ttl);
   return value;
 }
+
+export function makeCacheGetterAndSetter<T>(
+  key: string,
+  ttl: number,
+  fetcher: () => Promise<T>,
+  parser?: (value: T) => T
+) {
+  return {
+    get: async () => {
+      return getCachedValue(key, ttl, fetcher, parser);
+    },
+    set: async () => {
+      const value = await fetcher();
+      await redisCache.set(key, value, ttl);
+    },
+  };
+}
diff --git a/api/_utils.ts b/api/_utils.ts
index 18c868466..58dcac2b5 100644
--- a/api/_utils.ts
+++ b/api/_utils.ts
@@ -54,7 +54,11 @@ import {
   relayerFeeCapitalCostConfig,
 } from "./_constants";
 import { PoolStateOfUser, PoolStateResult } from "./_types";
-import { buildInternalCacheKey, getCachedValue } from "./_cache";
+import {
+  buildInternalCacheKey,
+  getCachedValue,
+  makeCacheGetterAndSetter,
+} from "./_cache";
 
 type LoggingUtility = sdk.relayFeeCalculator.Logger;
 type RpcProviderName = keyof typeof rpcProvidersJson.providers.urls;
@@ -1085,7 +1089,11 @@ export const getCachedTokenBalance = async (
   account: string,
   token: string
 ): Promise<BigNumber> => {
-  const balance = await getCachedLatestBalance(Number(chainId), token, account);
+  const balance = await latestBalanceCache(
+    Number(chainId),
+    token,
+    account
+  ).get();
   return balance;
 };
 
@@ -1896,34 +1904,17 @@ export function getCachedLatestBlock(chainId: number) {
   );
 }
 
-export function getCachedGasPrice(chainId: number) {
-  const ttlPerChain = {
-    default: 5,
-    [CHAIN_IDs.ARBITRUM]: 2,
-  };
-
-  return getCachedValue(
-    buildInternalCacheKey("gasPrice", chainId),
-    ttlPerChain[chainId] || ttlPerChain.default,
-    async () => {
-      const gasPrice = await getProvider(chainId).getGasPrice();
-      return gasPrice.mul(2);
-    },
-    (bnFromCache) => BigNumber.from(bnFromCache)
-  );
-}
-
-export function getCachedLatestBalance(
+export function latestBalanceCache(
   chainId: number,
   tokenAddress: string,
   address: string
 ) {
   const ttlPerChain = {
-    default: 30,
-    [CHAIN_IDs.MAINNET]: 30,
+    default: 60,
+    [CHAIN_IDs.MAINNET]: 60,
   };
 
-  return getCachedValue(
+  return makeCacheGetterAndSetter(
     buildInternalCacheKey("latestBalance", tokenAddress, chainId, address),
     ttlPerChain[chainId] || ttlPerChain.default,
     () => getBalance(chainId, address, tokenAddress),
diff --git a/api/cron-cache-balances.ts b/api/cron-cache-balances.ts
new file mode 100644
index 000000000..a195b7527
--- /dev/null
+++ b/api/cron-cache-balances.ts
@@ -0,0 +1,69 @@
+import { VercelResponse } from "@vercel/node";
+import { ethers } from "ethers";
+import { TypedVercelRequest } from "./_types";
+
+import {
+  HUB_POOL_CHAIN_ID,
+  getLogger,
+  handleErrorCondition,
+  latestBalanceCache,
+} from "./_utils";
+
+import mainnetChains from "../src/data/chains_1.json";
+
+const handler = async (
+  _: TypedVercelRequest<Record<string, never>>,
+  response: VercelResponse
+) => {
+  const logger = getLogger();
+  logger.debug({
+    at: "CronCacheBalances",
+    message: "Starting cron job...",
+  });
+  try {
+    const {
+      REACT_APP_FULL_RELAYERS, // These are relayers running a full auto-rebalancing strategy.
+      REACT_APP_TRANSFER_RESTRICTED_RELAYERS, // These are relayers whose funds stay put.
+    } = process.env;
+
+    const fullRelayers = !REACT_APP_FULL_RELAYERS
+      ? []
+      : (JSON.parse(REACT_APP_FULL_RELAYERS) as string[]).map((relayer) => {
+          return ethers.utils.getAddress(relayer);
+        });
+    const transferRestrictedRelayers = !REACT_APP_TRANSFER_RESTRICTED_RELAYERS
+      ? []
+      : (JSON.parse(REACT_APP_TRANSFER_RESTRICTED_RELAYERS) as string[]).map(
+          (relayer) => {
+            return ethers.utils.getAddress(relayer);
+          }
+        );
+
+    // Skip cron job on testnet
+    if (HUB_POOL_CHAIN_ID !== 1) {
+      return;
+    }
+
+    for (const chain of mainnetChains) {
+      for (const token of chain.inputTokens) {
+        const setTokenBalance = async (relayer: string) => {
+          await latestBalanceCache(chain.chainId, relayer, token.address).set();
+        };
+        await Promise.all([
+          Promise.all(fullRelayers.map(setTokenBalance)),
+          Promise.all(transferRestrictedRelayers.map(setTokenBalance)),
+        ]);
+      }
+    }
+
+    logger.debug({
+      at: "CronCacheBalances",
+      message: "Finished",
+    });
+    response.status(200);
+  } catch (error: unknown) {
+    return handleErrorCondition("cron-cache-balances", response, logger, error);
+  }
+};
+
+export default handler;
diff --git a/vercel.json b/vercel.json
index 4c51df1e3..264a5b0b1 100644
--- a/vercel.json
+++ b/vercel.json
@@ -1,5 +1,11 @@
 {
   "devCommand": "yarn dev",
+  "crons": [
+    {
+      "path": "/api/cron-cache-balances",
+      "schedule": "* * * * *"
+    }
+  ],
   "rewrites": [
     {
       "source": "/api/deposit/status",