feat: env var to override the node used for the faucet #257

Author: zone117x

.env

@@ -13,6 +13,9 @@ STACKS_BLOCKCHAIN_API_HOST=127.0.0.1
 STACKS_CORE_RPC_HOST=127.0.0.1
 STACKS_CORE_RPC_PORT=20443
 
+# STACKS_FAUCET_NODE_HOST=<IP or hostname>
+# STACKS_FAUCET_NODE_PORT=<port number>
+
 BTC_RPC_HOST=http://127.0.0.1
 BTC_RPC_PORT=18443
 BTC_RPC_USER=btc

src/api/routes/faucets.ts

@@ -1,15 +1,31 @@
+import * as process from 'process';
 import * as express from 'express';
 import { addAsync, RouterWithAsync } from '@awaitjs/express';
 import * as btc from 'bitcoinjs-lib';
 import PQueue from 'p-queue';
 import * as BN from 'bn.js';
-import { makeSTXTokenTransfer } from '@blockstack/stacks-transactions';
+import { makeSTXTokenTransfer, StacksNetwork } from '@blockstack/stacks-transactions';
 import { makeBtcFaucetPayment, getBtcBalance } from '../../btc-faucet';
 import { DataStore, DbFaucetRequestCurrency } from '../../datastore/common';
 import { logger } from '../../helpers';
 import { testnetKeys, GetStacksTestnetNetwork } from './debug';
 import { StacksCoreRpcClient } from '../../core-rpc/client';
 
+export function getStxFaucetNetwork(): StacksNetwork {
+  const network = GetStacksTestnetNetwork();
+  const faucetNodeHostOverride: string | undefined = process.env.STACKS_FAUCET_NODE_HOST;
+  if (faucetNodeHostOverride) {
+    const faucetNodePortOverride: string | undefined = process.env.STACKS_FAUCET_NODE_PORT;
+    if (!faucetNodePortOverride) {
+      const error = 'STACKS_FAUCET_NODE_HOST is specified but STACKS_FAUCET_NODE_PORT is missing';
+      logger.error(error);
+      throw new Error(error);
+    }
+    network.coreApiUrl = `http://${faucetNodeHostOverride}:${faucetNodePortOverride}`;
+  }
+  return network;
+}
+
 export function createFaucetRouter(db: DataStore): RouterWithAsync {
   const router = addAsync(express.Router());
   router.use(express.urlencoded({ extended: true }));
@@ -93,7 +109,7 @@ export function createFaucetRouter(db: DataStore): RouterWithAsync {
         recipient: address,
         amount: new BN(stxAmount),
         senderKey: privateKey,
-        network: GetStacksTestnetNetwork(),
+        network: getStxFaucetNetwork(),
         memo: 'Faucet',
       });
 

src/tests/faucet-tests.ts renamed to src/tests/faucet-btc-tests.ts

@@ -0,0 +1,20 @@
+import * as process from 'process';
+import { getStxFaucetNetwork } from '../api/routes/faucets';
+
+describe('stx faucet', () => {
+  test('faucet node env var override', () => {
+    const faucetDefault = getStxFaucetNetwork();
+    expect(faucetDefault.coreApiUrl).toBe('http://127.0.0.1:20443');
+
+    process.env.STACKS_FAUCET_NODE_HOST = '1.2.3.4';
+    process.env.STACKS_FAUCET_NODE_PORT = '12345';
+
+    try {
+      const faucetOverride = getStxFaucetNetwork();
+      expect(faucetOverride.coreApiUrl).toBe('http://1.2.3.4:12345');
+    } finally {
+      delete process.env.STACKS_FAUCET_NODE_HOST;
+      delete process.env.STACKS_FAUCET_NODE_PORT;
+    }
+  });
+});