feat: gas info (#38)

libs/metrics/src/exceptions/provider.exception.ts

@@ -0,0 +1,13 @@
+export class ProviderException extends Error {
+    constructor(message: string) {
+        super(message);
+        this.name = "ProviderException";
+    }
+}
+
+export class L1ProviderException extends ProviderException {
+    constructor(message: string) {
+        super(message);
+        this.name = "L1ProviderException";
+    }
+}

libs/metrics/src/l1/l1MetricsService.ts

@@ -1,22 +1,36 @@
 import assert from "assert";
+import { isNativeError } from "util/types";
 import { Inject, Injectable, LoggerService } from "@nestjs/common";
 import { WINSTON_MODULE_NEST_PROVIDER } from "nest-winston";
 import {
     Address,
     ContractConstructorArgs,
+    encodeFunctionData,
+    erc20Abi,
     formatUnits,
     parseAbiParameters,
+    parseEther,
     parseUnits,
+    zeroAddress,
 } from "viem";
 
+import { L1ProviderException } from "@zkchainhub/metrics/exceptions/provider.exception";
 import { bridgeHubAbi, sharedBridgeAbi } from "@zkchainhub/metrics/l1/abis";
 import { tokenBalancesAbi } from "@zkchainhub/metrics/l1/abis/tokenBalances.abi";
 import { tokenBalancesBytecode } from "@zkchainhub/metrics/l1/bytecode";
-import { AssetTvl } from "@zkchainhub/metrics/types";
+import { AssetTvl, GasInfo } from "@zkchainhub/metrics/types";
 import { IPricingService, PRICING_PROVIDER } from "@zkchainhub/pricing";
 import { EvmProviderService } from "@zkchainhub/providers";
-import { AbiWithAddress, ChainId, L1_CONTRACTS } from "@zkchainhub/shared";
-import { erc20Tokens, isNativeToken, tokens } from "@zkchainhub/shared/tokens/tokens";
+import { AbiWithAddress, ChainId, L1_CONTRACTS, vitalikAddress } from "@zkchainhub/shared";
+import {
+    erc20Tokens,
+    isNativeToken,
+    nativeToken,
+    tokens,
+    WETH,
+} from "@zkchainhub/shared/tokens/tokens";
+
+const ONE_ETHER = parseEther("1");
 
 /**
  * Acts as a wrapper around Viem library to provide methods to interact with an EVM-based blockchain.
@@ -147,10 +161,59 @@ export class L1MetricsService {
     async chainType(_chainId: number): Promise<"validium" | "rollup"> {
         return "rollup";
     }
-    //TODO: Implement ethGasInfo.
-    async ethGasInfo(): Promise<{ gasPrice: number; ethTransfer: number; erc20Transfer: number }> {
-        return { gasPrice: 50, ethTransfer: 21000, erc20Transfer: 65000 };
+
+    /**
+     * Retrieves gas information for Ethereum transfers and ERC20 token transfers.
+     * @returns {GasInfo} A promise that resolves to an object containing gas-related information.
+     */
+    async ethGasInfo(): Promise<GasInfo> {
+        try {
+            const [ethTransferGasCost, erc20TransferGasCost, gasPrice] = await Promise.all([
+                // Estimate gas for an ETH transfer.
+                this.evmProviderService.estimateGas({
+                    account: vitalikAddress,
+                    to: zeroAddress,
+                    value: ONE_ETHER,
+                }),
+                // Estimate gas for an ERC20 transfer.
+                this.evmProviderService.estimateGas({
+                    account: vitalikAddress,
+                    to: WETH.contractAddress,
+                    data: encodeFunctionData({
+                        abi: erc20Abi,
+                        functionName: "transfer",
+                        args: [L1_CONTRACTS.SHARED_BRIDGE, ONE_ETHER],
+                    }),
+                }),
+                // Get the current gas price.
+                this.evmProviderService.getGasPrice(),
+            ]);
+
+            // Get the current price of ether.
+            let ethPriceInUsd: number | undefined = undefined;
+            try {
+                const priceResult = await this.pricingService.getTokenPrices([
+                    nativeToken.coingeckoId,
+                ]);
+                ethPriceInUsd = priceResult[nativeToken.coingeckoId];
+            } catch (e) {
+                this.logger.error("Failed to get the price of ether.");
+            }
+
+            return {
+                gasPrice,
+                ethPrice: ethPriceInUsd,
+                ethTransferGas: ethTransferGasCost,
+                erc20TransferGas: erc20TransferGasCost,
+            };
+        } catch (e: unknown) {
+            if (isNativeError(e)) {
+                this.logger.error(`Failed to get gas information: ${e.message}`);
+            }
+            throw new L1ProviderException("Failed to get gas information from L1.");
+        }
     }
+
     //TODO: Implement feeParams.
     async feeParams(_chainId: number): Promise<{
         batchOverheadL1Gas: number;

libs/metrics/src/types/gasInfo.type.ts

@@ -0,0 +1,6 @@
+export type GasInfo = {
+    gasPrice: bigint; // wei
+    ethPrice?: number; // USD
+    ethTransferGas: bigint; // units of gas
+    erc20TransferGas: bigint; // units of gas
+};

libs/metrics/src/types/index.ts

@@ -1 +1,2 @@
+export * from "./gasInfo.type";
 export * from "./tvl.type";

libs/metrics/test/unit/l1/l1MetricsService.spec.ts

@@ -2,34 +2,26 @@ import { createMock } from "@golevelup/ts-jest";
 import { Logger } from "@nestjs/common";
 import { Test, TestingModule } from "@nestjs/testing";
 import { WINSTON_MODULE_PROVIDER } from "nest-winston";
+import { encodeFunctionData, erc20Abi, parseEther, zeroAddress } from "viem";
 
+import { L1ProviderException } from "@zkchainhub/metrics/exceptions/provider.exception";
 import { L1MetricsService } from "@zkchainhub/metrics/l1/";
 import { bridgeHubAbi, sharedBridgeAbi } from "@zkchainhub/metrics/l1/abis";
 import { tokenBalancesAbi } from "@zkchainhub/metrics/l1/abis/tokenBalances.abi";
 import { tokenBalancesBytecode } from "@zkchainhub/metrics/l1/bytecode";
 import { IPricingService, PRICING_PROVIDER } from "@zkchainhub/pricing";
 import { EvmProviderService } from "@zkchainhub/providers";
-import { L1_CONTRACTS } from "@zkchainhub/shared";
+import { L1_CONTRACTS, vitalikAddress } from "@zkchainhub/shared";
+import { nativeToken, WETH } from "@zkchainhub/shared/tokens/tokens";
 
 // Mock implementations of the dependencies
 const mockEvmProviderService = createMock<EvmProviderService>();
 
 const mockPricingService = createMock<IPricingService>();
 
+const ONE_ETHER = parseEther("1");
 jest.mock("@zkchainhub/shared/tokens/tokens", () => ({
     ...jest.requireActual("@zkchainhub/shared/tokens/tokens"),
-    get nativeToken() {
-        return {
-            name: "Ethereum",
-            symbol: "ETH",
-            contractAddress: null,
-            coingeckoId: "ethereum",
-            type: "native",
-            imageUrl:
-                "https://coin-images.coingecko.com/coins/images/279/large/ethereum.png?1696501628",
-            decimals: 18,
-        };
-    },
     get erc20Tokens() {
         return [
             {
@@ -107,11 +99,15 @@ describe("L1MetricsService", () => {
                 {
                     provide: L1MetricsService,
                     useFactory: (
-                        evmProviderService: EvmProviderService,
-                        pricingService: IPricingService,
+                        mockEvmProviderService: EvmProviderService,
+                        mockPricingService: IPricingService,
                         logger: Logger,
                     ) => {
-                        return new L1MetricsService(evmProviderService, pricingService, logger);
+                        return new L1MetricsService(
+                            mockEvmProviderService,
+                            mockPricingService,
+                            logger,
+                        );
                     },
                     inject: [EvmProviderService, PRICING_PROVIDER, WINSTON_MODULE_PROVIDER],
                 },
@@ -267,9 +263,151 @@ describe("L1MetricsService", () => {
     });
 
     describe("ethGasInfo", () => {
-        it("return ethGasInfo", async () => {
+        it("returns gas information from L1", async () => {
+            // Mock the necessary dependencies
+            const mockEstimateGas = jest.spyOn(mockEvmProviderService, "estimateGas");
+            mockEstimateGas.mockResolvedValueOnce(BigInt(21000)); // ethTransferGasCost
+            mockEstimateGas.mockResolvedValueOnce(BigInt(65000)); // erc20TransferGasCost'
+            const mockGetGasPrice = jest.spyOn(mockEvmProviderService, "getGasPrice");
+            mockGetGasPrice.mockResolvedValueOnce(BigInt(50000000000)); // gasPrice
+
+            const mockGetTokenPrices = jest.spyOn(mockPricingService, "getTokenPrices");
+            mockGetTokenPrices.mockResolvedValueOnce({ [nativeToken.coingeckoId]: 2000 }); // ethPriceInUsd
+
+            // Call the method
             const result = await l1MetricsService.ethGasInfo();
-            expect(result).toEqual({ gasPrice: 50, ethTransfer: 21000, erc20Transfer: 65000 });
+
+            // Assertions
+            expect(mockEstimateGas).toHaveBeenCalledTimes(2);
+            expect(mockEstimateGas).toHaveBeenNthCalledWith(1, {
+                account: vitalikAddress,
+                to: zeroAddress,
+                value: ONE_ETHER,
+            });
+            expect(mockEstimateGas).toHaveBeenNthCalledWith(2, {
+                account: vitalikAddress,
+                to: WETH.contractAddress,
+                data: encodeFunctionData({
+                    abi: erc20Abi,
+                    functionName: "transfer",
+                    args: [L1_CONTRACTS.SHARED_BRIDGE, ONE_ETHER],
+                }),
+            });
+
+            expect(mockGetGasPrice).toHaveBeenCalledTimes(1);
+
+            expect(mockGetTokenPrices).toHaveBeenCalledTimes(1);
+            expect(mockGetTokenPrices).toHaveBeenCalledWith([nativeToken.coingeckoId]);
+
+            expect(result).toEqual({
+                gasPrice: 50000000000n,
+                ethPrice: 2000,
+                ethTransferGas: 21000n,
+                erc20TransferGas: 65000n,
+            });
+        });
+
+        it("returns gas information from L1 without ether price", async () => {
+            const mockEstimateGas = jest.spyOn(mockEvmProviderService, "estimateGas");
+            mockEstimateGas.mockResolvedValueOnce(BigInt(21000)); // ethTransferGasCost
+            mockEstimateGas.mockResolvedValueOnce(BigInt(65000)); // erc20TransferGasCost
+
+            const mockGetGasPrice = jest.spyOn(mockEvmProviderService, "getGasPrice");
+            mockGetGasPrice.mockResolvedValueOnce(BigInt(50000000000)); // gasPrice
+
+            const mockGetTokenPrices = jest.spyOn(mockPricingService, "getTokenPrices");
+            mockGetTokenPrices.mockRejectedValueOnce(new Error("Failed to get token prices"));
+
+            const result = await l1MetricsService.ethGasInfo();
+
+            // Assertions
+            expect(result).toEqual({
+                gasPrice: 50000000000n,
+                ethPrice: undefined,
+                ethTransferGas: 21000n,
+                erc20TransferGas: 65000n,
+            });
+            expect(mockEstimateGas).toHaveBeenCalledTimes(2);
+            expect(mockEstimateGas).toHaveBeenNthCalledWith(1, {
+                account: vitalikAddress,
+                to: zeroAddress,
+                value: ONE_ETHER,
+            });
+            expect(mockEstimateGas).toHaveBeenNthCalledWith(2, {
+                account: vitalikAddress,
+                to: WETH.contractAddress,
+                data: encodeFunctionData({
+                    abi: erc20Abi,
+                    functionName: "transfer",
+                    args: [L1_CONTRACTS.SHARED_BRIDGE, ONE_ETHER],
+                }),
+            });
+
+            expect(mockGetGasPrice).toHaveBeenCalledTimes(1);
+
+            expect(mockGetTokenPrices).toHaveBeenCalledTimes(1);
+            expect(mockGetTokenPrices).toHaveBeenCalledWith([nativeToken.coingeckoId]);
+        });
+
+        it("throws L1ProviderException when estimateGas fails", async () => {
+            // Mock the necessary dependencies
+            const mockEstimateGas = jest.spyOn(mockEvmProviderService, "estimateGas");
+            mockEstimateGas.mockRejectedValueOnce(new Error("Failed to estimate gas"));
+
+            const mockGetGasPrice = jest.spyOn(mockEvmProviderService, "getGasPrice");
+            mockGetGasPrice.mockResolvedValueOnce(BigInt(50000000000)); // gasPrice
+
+            const mockGetTokenPrices = jest.spyOn(mockPricingService, "getTokenPrices");
+            mockGetTokenPrices.mockResolvedValueOnce({ [nativeToken.coingeckoId]: 2000 }); // ethPriceInUsd
+
+            // Call the method and expect it to throw L1ProviderException
+            await expect(l1MetricsService.ethGasInfo()).rejects.toThrow(L1ProviderException);
+
+            // Assertions
+            expect(mockEstimateGas).toHaveBeenCalledWith({
+                account: vitalikAddress,
+                to: zeroAddress,
+                value: ONE_ETHER,
+            });
+
+            expect(mockGetTokenPrices).not.toHaveBeenCalled();
+        });
+
+        it("throws L1ProviderException when getGasPrice fails", async () => {
+            // Mock the necessary dependencies
+            const mockEstimateGas = jest.spyOn(mockEvmProviderService, "estimateGas");
+            mockEstimateGas.mockResolvedValueOnce(BigInt(21000)); // ethTransferGasCost
+            mockEstimateGas.mockResolvedValueOnce(BigInt(65000)); // erc20TransferGasCost
+
+            const mockGetGasPrice = jest.spyOn(mockEvmProviderService, "getGasPrice");
+            mockGetGasPrice.mockRejectedValueOnce(new Error("Failed to get gas price"));
+
+            const mockGetTokenPrices = jest.spyOn(mockPricingService, "getTokenPrices");
+            mockGetTokenPrices.mockResolvedValueOnce({ [nativeToken.coingeckoId]: 2000 }); // ethPriceInUsd
+
+            // Call the method and expect it to throw L1ProviderException
+            await expect(l1MetricsService.ethGasInfo()).rejects.toThrow(L1ProviderException);
+
+            // Assertions
+            expect(mockEstimateGas).toHaveBeenCalledTimes(2);
+            expect(mockEstimateGas).toHaveBeenNthCalledWith(1, {
+                account: vitalikAddress,
+                to: zeroAddress,
+                value: ONE_ETHER,
+            });
+            expect(mockEstimateGas).toHaveBeenNthCalledWith(2, {
+                account: vitalikAddress,
+                to: WETH.contractAddress,
+                data: encodeFunctionData({
+                    abi: erc20Abi,
+                    functionName: "transfer",
+                    args: [L1_CONTRACTS.SHARED_BRIDGE, ONE_ETHER],
+                }),
+            });
+
+            expect(mockGetGasPrice).toHaveBeenCalledTimes(1);
+
+            expect(mockGetTokenPrices).not.toHaveBeenCalled();
         });
     });
 

libs/providers/src/providers/evmProvider.service.ts

@@ -13,6 +13,7 @@ import {
     decodeAbiParameters,
     DecodeAbiParametersReturnType,
     encodeDeployData,
+    EstimateGasParameters,
     GetBlockReturnType,
     Hex,
     http,
@@ -74,6 +75,10 @@ export class EvmProviderService {
         return this.client.getGasPrice();
     }
 
+    async estimateGas(args: EstimateGasParameters<typeof this.chain>): Promise<bigint> {
+        return this.client.estimateGas(args);
+    }
+
     /**
      * Retrieves the value from a storage slot at a given address.
      * @param {Address} address The address of the contract.

libs/providers/test/unit/providers/evmProvider.service.spec.ts

@@ -99,6 +99,24 @@ describe("EvmProviderService", () => {
         });
     });
 
+    describe("estimateGas", () => {
+        it("return the estimated gas for the given transaction", async () => {
+            const args = createMock<viem.EstimateGasParameters<typeof localhost>>({
+                account: "0xffff",
+                to: viem.zeroAddress,
+                value: 100n,
+            });
+
+            const expectedGas = 50000n;
+            jest.spyOn(mockClient, "estimateGas").mockResolvedValue(expectedGas);
+
+            const gas = await viemProvider.estimateGas(args);
+
+            expect(gas).toBe(expectedGas);
+            expect(mockClient.estimateGas).toHaveBeenCalledWith(args);
+        });
+    });
+
     describe("getStorageAt", () => {
         it("should return the value of the storage slot at the given address and slot number", async () => {
             const address = "0x123456789";

libs/shared/src/constants/addresses.ts

@@ -0,0 +1,3 @@
+import { Address } from "abitype";
+
+export const vitalikAddress: Address = "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045";

libs/shared/src/constants/index.ts

@@ -1,3 +1,4 @@
 export * from "./l1";
+export * from "./addresses";
 export const TOKEN_CACHE_TTL_IN_SEC = 60;
 export const BASE_CURRENCY = "usd";