evm-watcher: Add logic to group events for dispatch (#242)

* Add logic to group events for dispatch

* Add comment about one important assumption

* Address review comments

Author: ali-behjati

third_party/pyth/evm-watcher/package-lock.json

@@ -38,7 +38,9 @@
     "typescript": "^4.7.4"
   },
   "dependencies": {
+    "@pythnetwork/pyth-sdk-solidity": "^0.4.0",
     "dotenv": "^16.0.1",
+    "lru-cache": "^7.13.1",
     "web3": "^1.7.4",
     "web3-eth-contract": "^1.7.4",
     "web3-providers-ws": "^1.7.4",

third_party/pyth/evm-watcher/package.json

@@ -0,0 +1,48 @@
+import { HexString, NumberString, UnixTimestampString } from "./utils"
+
+export type PriceFeedUpdateEventValues = {
+  id: HexString,
+  fresh: boolean,
+  chainId: NumberString,
+  sequenceNumber: NumberString,
+  lastPublishTime: UnixTimestampString,
+  publishTime: UnixTimestampString,
+  price: NumberString,
+  conf: NumberString
+}
+
+export type PriceFeedInfo = PriceFeedUpdateEventValues;
+
+export type BatchPriceFeedUpdateEventValues = {
+  chainId: NumberString,
+  sequenceNumber: NumberString,
+  batchSize: NumberString,
+  freshPricesInBatch: NumberString,
+}
+
+export type BatchPriceFeedInfo = BatchPriceFeedUpdateEventValues & {
+  priceUpdates: PriceFeedUpdateEventValues[];
+}
+
+export type UpdatePriceFeedsEventValues = {
+  sender: HexString,
+  batchCount: NumberString,
+  fee: NumberString,
+};
+
+export type UpdatePriceFeedsInfo = UpdatePriceFeedsEventValues & {
+  batchUpdates: BatchPriceFeedInfo[];
+}
+
+export type UpdatePriceFeedsAggregateInfo = {
+  txHash: HexString,
+  txFrom: HexString,
+  txTo?: HexString,
+  block: number,
+  timestamp: UnixTimestampString,
+  rawInput: string,
+  gasUsage: number,
+  gasPrice: NumberString,
+  effectiveGasPrice?: number,
+  updatePriceFeedsInfo: UpdatePriceFeedsInfo, // Assuming there is only one UpdatePriceFeeds Event in a transaction
+}

third_party/pyth/evm-watcher/src/abi.json

@@ -1,4 +1,4 @@
-import { PythUpdateEvent } from "./pyth-update-event";
+import { UpdatePriceFeedsAggregateInfo } from "./events";
 import { Watcher } from "./watcher";
 
 export class Handler {
@@ -8,7 +8,7 @@ export class Handler {
     this.watchers = [];
   }
 
-  dispatchEvent(event: PythUpdateEvent) {
+  dispatchEvent(event: UpdatePriceFeedsAggregateInfo) {
     for (let watcher of this.watchers) {
       watcher.processEvent(event);
     }

third_party/pyth/evm-watcher/src/events.ts

@@ -1,7 +1,7 @@
 import { Handler } from "./handler";
 import { Listener } from "./listener";
 import { envOrErr } from "./utils";
-import { Logger } from "./watchers/logger";
+import { JsonLogger } from "./watchers/json-logger";
 
 console.log("Loading config file .env");
 require("dotenv").config();
@@ -13,7 +13,7 @@ const listener = new Listener({
 }, handler);
 
 // Initialize Watchers
-const logger = new Logger();
-handler.subscribe(logger);
+const jsonLogger = new JsonLogger();
+handler.subscribe(jsonLogger);
 
 listener.start();