feat: Implement eth.calculateFeeData (#6795)

* implement and test `calculateFeeData`

* add integration test for `calculateFeeData`

* update CHANGELOG.md file

packages/web3-eth/src/web3_eth.ts

@@ -22,6 +22,7 @@ import {
 	SupportedProviders,
 	Address,
 	Bytes,
+	FeeData,
 	Filter,
 	HexString32Bytes,
 	HexString8Bytes,
@@ -38,10 +39,12 @@ import {
 	DataFormat,
 	DEFAULT_RETURN_FORMAT,
 	Eip712TypedData,
+	FMT_BYTES,
+	FMT_NUMBER,
 } from 'web3-types';
 import { isSupportedProvider, Web3Context, Web3ContextInitOptions } from 'web3-core';
 import { TransactionNotFound } from 'web3-errors';
-import { toChecksumAddress, isNullish } from 'web3-utils';
+import { toChecksumAddress, isNullish, ethUnitMap } from 'web3-utils';
 import { ethRpcMethods } from 'web3-rpc-methods';
 
 import * as rpcMethodsWrappers from './rpc_method_wrappers.js';
@@ -72,27 +75,27 @@ export const registeredSubscriptions = {
 };
 
 /**
- * 
+ *
  * The Web3Eth allows you to interact with an Ethereum blockchain.
- *  
+ *
  * For using Web3 Eth functions, first install Web3 package using `npm i web3` or `yarn add web3` based on your package manager usage.
- * After that, Web3 Eth functions will be available as mentioned in following snippet. 
+ * After that, Web3 Eth functions will be available as mentioned in following snippet.
  * ```ts
  * import { Web3 } from 'web3';
  * const web3 = new Web3('https://mainnet.infura.io/v3/<YOURPROJID>');
- * 
+ *
  * const block = await web3.eth.getBlock(0);
- * 
+ *
  * ```
- * 
+ *
  * For using individual package install `web3-eth` package using `npm i web3-eth` or `yarn add web3-eth` and only import required functions.
- * This is more efficient approach for building lightweight applications. 
+ * This is more efficient approach for building lightweight applications.
  * ```ts
  * import { Web3Eth } from 'web3-eth';
- * 
+ *
  * const eth = new Web3Eth('https://mainnet.infura.io/v3/<YOURPROJID>');
  * const block = await eth.getBlock(0);
- * 
+ *
  * ```
  */
 export class Web3Eth extends Web3Context<Web3EthExecutionAPI, RegisteredSubscription> {
@@ -103,6 +106,7 @@ export class Web3Eth extends Web3Context<Web3EthExecutionAPI, RegisteredSubscrip
 			typeof providerOrContext === 'string' ||
 			isSupportedProvider(providerOrContext as SupportedProviders<any>)
 		) {
+			// @ts-expect-error disable the error: "A 'super' call must be a root-level statement within a constructor of a derived class that contains initialized properties, parameter properties, or private identifiers."
 			super({
 				provider: providerOrContext as SupportedProviders<any>,
 				registeredSubscriptions,
@@ -256,6 +260,81 @@ export class Web3Eth extends Web3Context<Web3EthExecutionAPI, RegisteredSubscrip
 		return rpcMethodsWrappers.getMaxPriorityFeePerGas(this, returnFormat);
 	}
 
+	/**
+	 * Calculates the current Fee Data.
+	 * If the node supports EIP-1559, then the `maxFeePerGas` and `maxPriorityFeePerGas` will be calculated.
+	 * If the node does not support EIP-1559, then the `gasPrice` will be returned and the rest are `null`s.
+	 *
+	 * @param baseFeePerGasFactor The factor to multiply the baseFeePerGas with, if the node supports EIP-1559.
+	 * @param alternativeMaxPriorityFeePerGas The alternative maxPriorityFeePerGas to use, if the node supports EIP-1559, but does not support the method `eth_maxPriorityFeePerGas`.
+	 * @returns The current fee data.
+	 *
+	 * ```ts
+	 * web3.eth.calculateFeeData().then(console.log);
+	 * > {
+	 *     gasPrice: 20000000000n,
+	 *     maxFeePerGas: 20000000000n,
+	 *     maxPriorityFeePerGas: 20000000000n,
+	 * 	   baseFeePerGas: 20000000000n
+	 * }
+	 *
+	 * web3.eth.calculateFeeData(ethUnitMap.Gwei, 2n).then(console.log);
+	 * > {
+	 *     gasPrice: 20000000000n,
+	 *     maxFeePerGas: 40000000000n,
+	 *     maxPriorityFeePerGas: 20000000000n,
+	 * 	   baseFeePerGas: 20000000000n
+	 * }
+	 * ```
+	 */
+	public async calculateFeeData(
+		baseFeePerGasFactor = BigInt(2),
+		alternativeMaxPriorityFeePerGas = ethUnitMap.Gwei,
+	): Promise<FeeData> {
+		const block = await this.getBlock<{ number: FMT_NUMBER.BIGINT; bytes: FMT_BYTES.HEX }>(
+			undefined,
+			false,
+		);
+
+		const baseFeePerGas: bigint | undefined = block?.baseFeePerGas ?? undefined; // use undefined if it was null
+
+		let gasPrice: bigint | undefined;
+		try {
+			gasPrice = await this.getGasPrice<{ number: FMT_NUMBER.BIGINT; bytes: FMT_BYTES.HEX }>();
+		} catch (error) {
+			// do nothing
+		}
+
+		let maxPriorityFeePerGas: bigint | undefined;
+		try {
+			maxPriorityFeePerGas = await this.getMaxPriorityFeePerGas<{
+				number: FMT_NUMBER.BIGINT;
+				bytes: FMT_BYTES.HEX;
+			}>();
+		} catch (error) {
+			// do nothing
+		}
+
+		let maxFeePerGas: bigint | undefined;
+		// if the `block.baseFeePerGas` is available, then EIP-1559 is supported
+		// and we can calculate the `maxFeePerGas` from the `block.baseFeePerGas`
+		if (baseFeePerGas) {
+			// tip the miner with alternativeMaxPriorityFeePerGas, if no value available from getMaxPriorityFeePerGas
+			maxPriorityFeePerGas = maxPriorityFeePerGas ?? alternativeMaxPriorityFeePerGas;
+			// basically maxFeePerGas = (baseFeePerGas +- 12.5%) + maxPriorityFeePerGas
+			// and we multiply the `baseFeePerGas` by `baseFeePerGasFactor`, to allow
+			// trying to include the transaction in the next few blocks even if the
+			// baseFeePerGas is increasing fast
+			maxFeePerGas = baseFeePerGas * baseFeePerGasFactor + maxPriorityFeePerGas;
+		}
+
+		return { gasPrice, maxFeePerGas, maxPriorityFeePerGas, baseFeePerGas };
+	}
+
+	// an alias for calculateFeeData
+	// eslint-disable-next-line
+	public getFeeData = this.calculateFeeData;
+
 	/**
 	 * @returns A list of accounts the node controls (addresses are checksummed).
 	 *

packages/web3-eth/test/integration/web3_eth/send_transaction.test.ts

@@ -290,6 +290,46 @@ describe('Web3Eth.sendTransaction', () => {
 			expect(minedTransactionData).toMatchObject(transaction);
 		});
 
+		it('should send a successful type 0x2 transaction (gas = estimateGas)', async () => {
+			const transaction: Transaction = {
+				from: tempAcc.address,
+				to: '0x0000000000000000000000000000000000000000',
+				value: BigInt(1),
+				type: BigInt(2),
+			};
+
+			transaction.gas = await web3Eth.estimateGas(transaction);
+
+			const response = await web3Eth.sendTransaction(transaction);
+			expect(response.events).toBeUndefined();
+			expect(response.type).toBe(BigInt(2));
+			expect(response.status).toBe(BigInt(1));
+
+			const minedTransactionData = await web3Eth.getTransaction(response.transactionHash);
+			expect(minedTransactionData).toMatchObject(transaction);
+		});
+
+		it('should send a successful type 0x2 transaction (fee per gas from: calculateFeeData)', async () => {
+			const transaction: Transaction = {
+				from: tempAcc.address,
+				to: '0x0000000000000000000000000000000000000000',
+				value: BigInt(1),
+				type: BigInt(2),
+			};
+
+			const feeData = await web3Eth.calculateFeeData();
+			transaction.maxPriorityFeePerGas = feeData.maxPriorityFeePerGas;
+			transaction.maxFeePerGas = feeData.maxFeePerGas;
+
+			const response = await web3Eth.sendTransaction(transaction);
+			expect(response.events).toBeUndefined();
+			expect(response.type).toBe(BigInt(2));
+			expect(response.status).toBe(BigInt(1));
+
+			const minedTransactionData = await web3Eth.getTransaction(response.transactionHash);
+			expect(minedTransactionData).toMatchObject(transaction);
+		});
+
 		it('should send a successful type 0x0 transaction with data', async () => {
 			const transaction: Transaction = {
 				from: tempAcc.address,

packages/web3-eth/test/unit/web3_eth_calculate_fee_data.test.ts

@@ -0,0 +1,84 @@
+/*
+This file is part of web3.js.
+
+web3.js is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+web3.js is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with web3.js.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+import { ethRpcMethods } from 'web3-rpc-methods';
+
+import Web3Eth from '../../src/index';
+
+jest.mock('web3-rpc-methods');
+
+describe('Web3Eth.calculateFeeData', () => {
+	let web3Eth: Web3Eth;
+
+	beforeAll(() => {
+		web3Eth = new Web3Eth('http://127.0.0.1:8545');
+	});
+
+	it('should return call getBlockByNumber, getGasPrice and getMaxPriorityFeePerGas', async () => {
+		await web3Eth.calculateFeeData();
+		// web3Eth.getBlock = jest.fn();
+		expect(ethRpcMethods.getBlockByNumber).toHaveBeenCalledWith(
+			web3Eth.requestManager,
+			'latest',
+			false,
+		);
+		expect(ethRpcMethods.getGasPrice).toHaveBeenCalledWith(web3Eth.requestManager);
+		expect(ethRpcMethods.getMaxPriorityFeePerGas).toHaveBeenCalledWith(web3Eth.requestManager);
+	});
+
+	it('should calculate fee data', async () => {
+		const gasPrice = BigInt(20 * 1000);
+		const baseFeePerGas = BigInt(1000);
+		const maxPriorityFeePerGas = BigInt(100);
+		const baseFeePerGasFactor = BigInt(3);
+
+		jest.spyOn(ethRpcMethods, 'getBlockByNumber').mockReturnValueOnce({ baseFeePerGas } as any);
+		jest.spyOn(ethRpcMethods, 'getGasPrice').mockReturnValueOnce(gasPrice as any);
+		// eslint-disable-next-line @typescript-eslint/no-unsafe-call
+		jest
+			.spyOn(ethRpcMethods, 'getMaxPriorityFeePerGas')
+			.mockReturnValueOnce(maxPriorityFeePerGas as any);
+
+		const feeData = await web3Eth.calculateFeeData(baseFeePerGasFactor, maxPriorityFeePerGas);
+		expect(feeData).toMatchObject({
+			gasPrice,
+			maxFeePerGas: baseFeePerGas * baseFeePerGasFactor + maxPriorityFeePerGas,
+			maxPriorityFeePerGas,
+			baseFeePerGas,
+		});
+	});
+
+	it('should calculate fee data based on `alternativeMaxPriorityFeePerGas` if `getMaxPriorityFeePerGas` did not return a value', async () => {
+		const gasPrice = BigInt(20 * 1000);
+		const baseFeePerGas = BigInt(1000);
+		const alternativeMaxPriorityFeePerGas = BigInt(700);
+		const baseFeePerGasFactor = BigInt(3);
+
+		jest.spyOn(ethRpcMethods, 'getBlockByNumber').mockReturnValueOnce({ baseFeePerGas } as any);
+		jest.spyOn(ethRpcMethods, 'getGasPrice').mockReturnValueOnce(gasPrice as any);
+		const feeData = await web3Eth.calculateFeeData(
+			baseFeePerGasFactor,
+			alternativeMaxPriorityFeePerGas,
+		);
+		expect(feeData).toMatchObject({
+			gasPrice,
+			maxFeePerGas: baseFeePerGas * baseFeePerGasFactor + alternativeMaxPriorityFeePerGas,
+			maxPriorityFeePerGas: alternativeMaxPriorityFeePerGas,
+			baseFeePerGas,
+		});
+	});
+});

packages/web3-types/CHANGELOG.md

@@ -183,4 +183,8 @@ Documentation:
 
 -   Adds missing exported type `AbiItem` from 1.x to v4 for compatabiltiy (#6678)
 
-## [Unreleased]
+## [Unreleased]
+
+### Added
+
+-   Type `FeeData` to be filled by `await web3.eth.calculateFeeData()` to be used with EIP-1559 transactions (#6795)

packages/web3-types/src/eth_types.ts

@@ -529,3 +529,48 @@ export interface Eip712TypedData {
 	readonly domain: Record<string, string | number>;
 	readonly message: Record<string, unknown>;
 }
+
+/**
+ * To contain the gas Fee Data to be used with EIP-1559 transactions.
+ * EIP-1559 was applied to Ethereum after London hardfork.
+ *  
+ * Typically you will only need `maxFeePerGas` and `maxPriorityFeePerGas` for a transaction following EIP-1559.
+ * However, if you want to get informed about the fees of last block, you can use `baseFeePerGas` too.
+ * 
+ * 
+ * 	@see https://eips.ethereum.org/EIPS/eip-1559
+ * 
+ */
+export interface FeeData {
+	/**
+	 * This filed is used for legacy networks that does not support EIP-1559.
+	 */
+	readonly gasPrice?: Numbers;
+
+	/**
+	 * The baseFeePerGas returned from the the last available block.
+	 * 
+	 * If EIP-1559 is not supported, this will be `undefined`
+	 * 
+	 * However, the user will only pay (the future baseFeePerGas + the maxPriorityFeePerGas). 
+	 * And this value is just for getting informed about the fees of last block.
+	 */
+	readonly baseFeePerGas?: Numbers;
+
+	/**
+	 * The maximum fee that the user would be willing to pay per-gas.
+	 * 
+	 * However, the user will only pay (the future baseFeePerGas + the maxPriorityFeePerGas).
+	 * And the `maxFeePerGas` could be used to prevent paying more than it, if `baseFeePerGas` went too high.
+	 * 
+	 * If EIP-1559 is not supported, this will be `undefined`
+	 */
+	readonly maxFeePerGas?: Numbers;
+
+	/**
+	 * The validator's tip for including a transaction in a block.
+	 *
+	 * If EIP-1559 is not supported, this will be `undefined`
+	 */
+	readonly maxPriorityFeePerGas?: Numbers;
+}