From 9041ccd22c76dfa8db1823f41d098aa46e0f6310 Mon Sep 17 00:00:00 2001
From: Justin Starry <justin@solana.com>
Date: Thu, 9 Sep 2021 13:34:43 -0400
Subject: [PATCH] feat: add support for getGenesisHash RPC (#19732)

---
 web3.js/src/connection.ts       | 12 ++++++++++++
 web3.js/test/connection.test.ts | 11 +++++++++++
 2 files changed, 23 insertions(+)

diff --git a/web3.js/src/connection.ts b/web3.js/src/connection.ts
index 3a4978b6e3b56b..ba947633d98fed 100644
--- a/web3.js/src/connection.ts
+++ b/web3.js/src/connection.ts
@@ -2963,6 +2963,18 @@ export class Connection {
     return res.result;
   }
 
+  /**
+   * Fetch the genesis hash
+   */
+  async getGenesisHash(): Promise<string> {
+    const unsafeRes = await this._rpcRequest('getGenesisHash', []);
+    const res = create(unsafeRes, jsonRpcResult(string()));
+    if ('error' in res) {
+      throw new Error('failed to get genesis hash: ' + res.error.message);
+    }
+    return res.result;
+  }
+
   /**
    * Fetch a processed block from the cluster.
    */
diff --git a/web3.js/test/connection.test.ts b/web3.js/test/connection.test.ts
index 344c89bb5c1540..91c2a248cdfeb5 100644
--- a/web3.js/test/connection.test.ts
+++ b/web3.js/test/connection.test.ts
@@ -2668,6 +2668,17 @@ describe('Connection', () => {
     expect(version['solana-core']).to.be.ok;
   });
 
+  it('getGenesisHash', async () => {
+    await mockRpcResponse({
+      method: 'getGenesisHash',
+      params: [],
+      value: 'GH7ome3EiwEr7tu9JuTh2dpYWBJK3z69Xm1ZE3MEE6JC',
+    });
+
+    const genesisHash = await connection.getGenesisHash();
+    expect(genesisHash).not.to.be.empty;
+  });
+
   it('request airdrop', async () => {
     const account = Keypair.generate();