From 6d67fbde84cbfe1495d7a35a5ee43499597eac3b Mon Sep 17 00:00:00 2001
From: softsimon <softsimon@protonmail.com>
Date: Tue, 22 Sep 2020 04:07:47 +0700
Subject: [PATCH] NodeJS cluster fix: Only save disk cache to disk when master.
 fixes #108

---
 backend/src/api/disk-cache.ts | 19 +++++++++++--------
 backend/src/index.ts          |  1 -
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/backend/src/api/disk-cache.ts b/backend/src/api/disk-cache.ts
index 30683f277..1e35fdf68 100644
--- a/backend/src/api/disk-cache.ts
+++ b/backend/src/api/disk-cache.ts
@@ -1,4 +1,5 @@
 import * as fs from 'fs';
+import * as cluster from 'cluster';
 import memPool from './mempool';
 import blocks from './blocks';
 
@@ -6,15 +7,17 @@ class DiskCache {
   static FILE_NAME = './cache.json';
 
   constructor() {
-    process.on('SIGINT', () => {
-      this.saveCacheToDisk();
-      process.exit(2);
-    });
+    if (cluster.isMaster) {
+      process.on('SIGINT', () => {
+        this.saveCacheToDisk();
+        process.exit(2);
+      });
 
-    process.on('SIGTERM', () => {
-      this.saveCacheToDisk();
-      process.exit(2);
-    });
+      process.on('SIGTERM', () => {
+        this.saveCacheToDisk();
+        process.exit(2);
+      });
+    }
   }
 
   saveCacheToDisk() {
diff --git a/backend/src/index.ts b/backend/src/index.ts
index 8a47ba797..e8123e95e 100644
--- a/backend/src/index.ts
+++ b/backend/src/index.ts
@@ -7,7 +7,6 @@ import * as http from 'http';
 import * as https from 'https';
 import * as WebSocket from 'ws';
 import * as cluster from 'cluster';
-import * as os from 'os';
 
 import { checkDbConnection } from './database';
 import routes from './routes';