feat: add AlchemyProvider class

.env

@@ -1,2 +1,3 @@
 RPC_ORIGIN=https://free-eth-node.com
 # RPC_ORIGIN=http://localhost:3000
+ALCHEMY_API_KEY=kwIkw24q335k05WBuFXBmT3W-P5luv4g

src/index.ts

@@ -1,4 +1,5 @@
 import { BaseContract, Contract } from './classes/Contract';
+import { AlchemyProvider } from './providers/AlchemyProvider';
 import {
   ConstructorOptions,
   FallthroughProvider,
@@ -47,6 +48,7 @@ export {
   jsonRpcProvider,
   JsonRpcProvider,
   FallthroughProvider,
+  AlchemyProvider,
   tinyBig,
   toChecksumAddress,
   weiToEther,

src/providers/AlchemyProvider.ts

@@ -0,0 +1,37 @@
+import { BaseProvider } from './BaseProvider';
+
+export class AlchemyProvider extends BaseProvider {
+  /**
+   * @ignore
+   */
+  selectRpcUrl(): string {
+    return this._rpcUrls[0];
+  }
+
+  /**
+   * @ignore
+   */
+  post(body: Record<string, unknown>): Promise<any> {
+    return this._post(body);
+  }
+
+  /**
+   * @param apiKey The Alchemy API key
+   * @param network The Ethereum network to connect to
+   */
+  constructor(apiKey: string, network = 'mainnet') {
+    const alchemyUrl = `https://eth-${network}.alchemyapi.io/v2/${apiKey}`;
+    super([alchemyUrl]);
+  }
+}
+
+/**
+ * Helper function to avoid "new"
+ *
+ * @param apiKey the Alchemy API key
+ * @param network the Ethereum network to connect to
+ * @returns an initiated {@link AlchemyProvider}
+ */
+export function alchemyProvider(apiKey: string, network?: string) {
+  return new AlchemyProvider(apiKey, network);
+}

src/providers/test/json-rpc-provider/get-block-number.test.ts

@@ -11,11 +11,9 @@ const mockPostResponse = JSON.stringify({
 describe('provider.getBlockNumber', () => {
   it('should get number integer', async () => {
     const essentialEthProvider = new JsonRpcProvider();
-    mockOf(unfetch).mockReturnValueOnce(
-      Promise.resolve({
-        text: () => mockPostResponse,
-      } as unknown as Response),
-    );
+    mockOf(unfetch).mockResolvedValueOnce({
+      text: () => mockPostResponse,
+    } as unknown as Response);
     const essentialEthBlockNumber = await essentialEthProvider.getBlockNumber();
     expect(essentialEthBlockNumber).toBe(10);
   });

src/providers/test/json-rpc-provider/get-gas-price.test.ts

@@ -17,11 +17,9 @@ const rpcUrl = rpcUrls.mainnet;
 describe('provider.getGasPrice', () => {
   it('should get TinyBig integer', async () => {
     const provider = new JsonRpcProvider(rpcUrl);
-    mockOf(unfetch).mockReturnValueOnce(
-      Promise.resolve({
-        text: () => mockPostResponse,
-      } as unknown as Response),
-    );
+    mockOf(unfetch).mockResolvedValueOnce({
+      text: () => mockPostResponse,
+    } as unknown as Response);
 
     const gasPrice = await provider.getGasPrice();
     expect(z.instanceof(TinyBig).safeParse(gasPrice).success).toBe(true);

src/providers/test/test-alchemy-provider.test.ts

@@ -0,0 +1,20 @@
+import { AlchemyProvider } from '../../index';
+import dotenv from 'dotenv';
+dotenv.config();
+
+const apiKey = process.env.ALCHEMY_API_KEY;
+
+if (!apiKey) {
+  throw new Error(
+    'ALCHEMY_API_KEY is not defined in the environment variables.',
+  );
+}
+
+const provider = new AlchemyProvider(apiKey);
+
+describe('alchemyProvider.getGasPrice', () => {
+  it('should return the current gas price', async () => {
+    const gasPrice = await provider.getGasPrice();
+    expect(gasPrice).toBeDefined();
+  });
+});