From 74d5544235462843cf6d0f082aeedabd5bbf401a Mon Sep 17 00:00:00 2001
From: Federico Galatolo <federico@segmentationfault>
Date: Sun, 24 Dec 2017 15:57:21 +0100
Subject: [PATCH] Added connection retry limit in case of errors

---
 config/defaults.js |  3 ++-
 package.json       |  6 +++++-
 src/Connection.ts  | 15 +++++++++++++--
 src/Proxy.ts       |  8 ++++++--
 4 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/config/defaults.js b/config/defaults.js
index 4098191..b2f4d30 100644
--- a/config/defaults.js
+++ b/config/defaults.js
@@ -17,5 +17,6 @@ module.exports = {
       pass: "donations",
       percentage: 0.01 // 1%
     }
-  ]
+  ],
+  maxRetry: 10,
 };
diff --git a/package.json b/package.json
index eeb6339..2883ea1 100644
--- a/package.json
+++ b/package.json
@@ -16,7 +16,11 @@
     "type": "git",
     "url": "git+https://github.com/cazala/coin-hive-stratum.git"
   },
-  "keywords": ["coinhive", "stratum", "proxy"],
+  "keywords": [
+    "coinhive",
+    "stratum",
+    "proxy"
+  ],
   "author": "",
   "license": "MIT",
   "bugs": {
diff --git a/src/Connection.ts b/src/Connection.ts
index 9ed8470..0e76616 100644
--- a/src/Connection.ts
+++ b/src/Connection.ts
@@ -24,6 +24,7 @@ export type Options = {
   port: number;
   ssl: boolean;
   donation: boolean;
+  maxRetry: number;
 };
 
 class Connection extends EventEmitter {
@@ -42,6 +43,9 @@ class Connection extends EventEmitter {
   miners: Miner[] = [];
   donations: Donation[] = [];
   donation: boolean;
+  connectionErrors: number = 0;
+  maxRetry: number = 0;
+  isDead: boolean = false;
 
   constructor(options: Options) {
     super();
@@ -49,6 +53,7 @@ class Connection extends EventEmitter {
     this.port = options.port;
     this.ssl = options.ssl;
     this.donation = options.donation;
+    this.maxRetry = options.maxRetry;
   }
 
   connect() {
@@ -64,9 +69,14 @@ class Connection extends EventEmitter {
     this.socket.on("connect", this.ready.bind(this));
     this.socket.on("error", error => {
       if (this.online) {
-        console.warn(`socket error (${this.host}:${this.port})`, error.message);
+        this.connectionErrors++
+        console.warn(`socket error (${this.host}:${this.port}) (Retry: ${this.connectionErrors})`, error.message);
         this.emit("error", error);
-        this.connect();
+        if(this.connectionErrors < this.maxRetry)
+          this.connect();
+        else
+          this.kill()
+          // [TODO] Broadcast the error to the miners
       }
     });
     this.socket.on("close", () => {
@@ -84,6 +94,7 @@ class Connection extends EventEmitter {
   }
 
   kill() {
+    this.isDead = true
     if (this.socket != null) {
       try {
         this.socket.end();
diff --git a/src/Proxy.ts b/src/Proxy.ts
index 4e4419d..720c6d1 100644
--- a/src/Proxy.ts
+++ b/src/Proxy.ts
@@ -38,6 +38,7 @@ export type Options = {
   path: string;
   server: http.Server | https.Server;
   credentials: Credentials;
+  maxRetry: number;
 };
 
 class Proxy extends EventEmitter {
@@ -59,6 +60,7 @@ class Proxy extends EventEmitter {
   server: http.Server | https.Server = null;
   credentials: Credentials = null;
   online: boolean = false;
+  maxRetry: number;
 
   constructor(constructorOptions: Partial<Options> = defaults) {
     super();
@@ -78,6 +80,7 @@ class Proxy extends EventEmitter {
     this.path = options.path;
     this.server = options.server;
     this.credentials = options.credentials;
+    this.maxRetry = options.maxRetry
     this.on("error", error => {
       /* prevent unhandled proxy errors from stopping the proxy */
       console.error("proxy error:", error.message);
@@ -248,7 +251,7 @@ class Proxy extends EventEmitter {
     const connections = this.connections[connectionId];
     const availableConnections = connections.filter(connection => this.isAvailable(connection));
     if (availableConnections.length === 0) {
-      const connection = new Connection({ host, port, ssl: this.ssl, donation });
+      const connection = new Connection({ host, port, ssl: this.ssl, donation, maxRetry: this.maxRetry });
       connection.connect();
       connection.on("close", () => {
         console.log(`connection closed (${connectionId})`);
@@ -265,7 +268,8 @@ class Proxy extends EventEmitter {
   isAvailable(connection: Connection): boolean {
     return (
       connection.miners.length < this.maxMinersPerConnection &&
-      connection.donations.length < this.maxMinersPerConnection
+      connection.donations.length < this.maxMinersPerConnection &&
+      !connection.isDead
     );
   }