added customGasStation (#644)

Author: Maurechi

price_pusher/src/custom-gas-station.ts

@@ -0,0 +1,34 @@
+import Web3 from "web3";
+import {
+  CustomGasChainId,
+  TxSpeed,
+  verifyValidOption,
+  txSpeeds,
+  customGasChainIds,
+} from "./utils";
+
+type chainMethods = Record<CustomGasChainId, () => Promise<string>>;
+
+export class CustomGasStation {
+  private chain: CustomGasChainId;
+  private speed: TxSpeed;
+  private chainMethods: chainMethods = {
+    137: this.fetchMaticMainnetGasPrice.bind(this),
+  };
+  constructor(chain: number, speed: string) {
+    this.speed = verifyValidOption(speed, txSpeeds);
+    this.chain = verifyValidOption(chain, customGasChainIds);
+  }
+
+  async getCustomGasPrice() {
+    return this.chainMethods[this.chain]();
+  }
+
+  private async fetchMaticMainnetGasPrice() {
+    const res = await fetch("https://gasstation-mainnet.matic.network/v2");
+    const jsonRes = await res.json();
+    const gasPrice = jsonRes[this.speed].maxFee;
+    const gweiGasPrice = Web3.utils.toWei(gasPrice.toFixed(2), "Gwei");
+    return gweiGasPrice.toString();
+  }
+}

price_pusher/src/evm.ts

@@ -17,6 +17,7 @@ import {
   HexString,
   UnixTimestamp,
 } from "@pythnetwork/pyth-common-js";
+import { CustomGasStation } from "./custom-gas-station";
 
 export class EvmPriceListener extends ChainPriceListener {
   private pythContractFactory: PythContractFactory;
@@ -117,10 +118,14 @@ export class EvmPriceListener extends ChainPriceListener {
 }
 
 export class EvmPricePusher implements ChainPricePusher {
+  private customGasStation?: CustomGasStation;
   constructor(
     private connection: PriceServiceConnection,
-    private pythContract: Contract
-  ) {}
+    private pythContract: Contract,
+    customGasStation?: CustomGasStation
+  ) {
+    this.customGasStation = customGasStation;
+  }
   // The pubTimes are passed here to use the values that triggered the push.
   // This is an optimization to avoid getting a newer value (as an update comes)
   // and will help multiple price pushers to have consistent behaviour.
@@ -145,19 +150,20 @@ export class EvmPricePusher implements ChainPricePusher {
       "Pushing ",
       priceIdsWith0x.map((priceIdWith0x) => `${priceIdWith0x}`)
     );
-
     const updateFee = await this.pythContract.methods
       .getUpdateFee(priceFeedUpdateData)
       .call();
     console.log(`Update fee: ${updateFee}`);
 
+    const gasPrice = await this.customGasStation?.getCustomGasPrice();
+
     this.pythContract.methods
       .updatePriceFeedsIfNecessary(
         priceFeedUpdateData,
         priceIdsWith0x,
         pubTimesToPush
       )
-      .send({ value: updateFee })
+      .send({ value: updateFee, gasPrice })
       .on("transactionHash", (hash: string) => {
         console.log(`Successful. Tx hash: ${hash}`);
       })

price_pusher/src/index.ts

@@ -12,6 +12,7 @@ import { readPriceConfigFile } from "./price-config";
 import { PriceServiceConnection } from "@pythnetwork/pyth-common-js";
 import { InjectivePriceListener, InjectivePricePusher } from "./injective";
 import { ChainPricePusher, IPriceListener } from "./interface";
+import { CustomGasStation } from "./custom-gas-station";
 
 const argv = yargs(hideBin(process.argv))
   .option("network", {
@@ -69,6 +70,18 @@ const argv = yargs(hideBin(process.argv))
     required: false,
     default: 5,
   })
+  .option("custom-gas-station", {
+    description:
+      "If using a custom gas station, chainId of custom gas station to use",
+    type: "number",
+    required: false,
+  })
+  .option("tx-speed", {
+    description:
+      "txSpeed for custom gas station. choose between 'slow'|'standard'|'fast'",
+    type: "string",
+    required: false,
+  })
   .help()
   .alias("help", "h")
   .parserConfiguration({
@@ -139,6 +152,7 @@ function getNetworkPriceListener(network: string): IPriceListener {
 }
 
 function getNetworkPricePusher(network: string): ChainPricePusher {
+  const gasStation = getCustomGasStation(argv.customGasStation, argv.txSpeed);
   switch (network) {
     case "evm": {
       const pythContractFactory = new PythContractFactory(
@@ -148,7 +162,8 @@ function getNetworkPricePusher(network: string): ChainPricePusher {
       );
       return new EvmPricePusher(
         priceServiceConnection,
-        pythContractFactory.createPythContractWithPayer()
+        pythContractFactory.createPythContractWithPayer(),
+        gasStation
       );
     }
     case "injective":
@@ -163,6 +178,12 @@ function getNetworkPricePusher(network: string): ChainPricePusher {
   }
 }
 
+function getCustomGasStation(customGasStation?: number, txSpeed?: string) {
+  if (customGasStation && txSpeed) {
+    return new CustomGasStation(customGasStation, txSpeed);
+  }
+}
+
 start({
   sourcePriceListener: pythPriceListener,
   targetPriceListener: getNetworkPriceListener(argv.network),

price_pusher/src/utils.ts

@@ -2,6 +2,10 @@ import { HexString } from "@pythnetwork/pyth-common-js";
 
 export type PctNumber = number;
 export type DurationInSeconds = number;
+export const txSpeeds = ["slow", "standard", "fast"] as const;
+export type TxSpeed = typeof txSpeeds[number];
+export const customGasChainIds = [137] as const;
+export type CustomGasChainId = typeof customGasChainIds[number];
 
 export async function sleep(ms: number): Promise<void> {
   return new Promise((resolve) => setTimeout(resolve, ms));
@@ -31,3 +35,15 @@ export function isWsEndpoint(endpoint: string): boolean {
 
   return false;
 }
+
+export function verifyValidOption<
+  options extends Readonly<Array<any>>,
+  validOption extends options[number]
+>(option: any, validOptions: options) {
+  if (validOptions.includes(option)) {
+    return option as validOption;
+  }
+  const errorString =
+    option + " is not a valid option. Please choose between " + validOptions;
+  throw new Error(errorString);
+}