From 53fca2406aa5d5e27d84520aef316664f30ed6cf Mon Sep 17 00:00:00 2001
From: Jaco <jacogr@gmail.com>
Date: Sun, 2 May 2021 10:24:10 +0300
Subject: [PATCH] Cleanup WebSocket handlers when close event has been received
 (#3469)

---
 CHANGELOG.md                          |  1 +
 packages/rpc-provider/src/ws/index.ts | 13 ++++++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 83842bb3e3..902496b988 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -12,6 +12,7 @@ Changes:
 - Expose additional camelCase `method` on `AbiMessage` (maps to decorated name)
 - Added explicit double-byte ss58 `AccountId` encoding test
 - Add known upgrade block for Polkadot v30
+- Cleanup WebSocket handlers when close event has been received
 - Update to latest Substrate metadata
 
 
diff --git a/packages/rpc-provider/src/ws/index.ts b/packages/rpc-provider/src/ws/index.ts
index 1fe897a66b..462cabf468 100644
--- a/packages/rpc-provider/src/ws/index.ts
+++ b/packages/rpc-provider/src/ws/index.ts
@@ -225,7 +225,6 @@ export class WsProvider implements ProviderInterface {
 
       // 1000 - Normal closure; the connection successfully completed
       this.#websocket.close(1000);
-      this.#websocket = null;
     } catch (error) {
       l.error(error);
 
@@ -351,11 +350,19 @@ export class WsProvider implements ProviderInterface {
     }
 
     this.#isConnected = false;
-    this.#websocket = null;
+
+    if (this.#websocket) {
+      this.#websocket.onclose = null;
+      this.#websocket.onerror = null;
+      this.#websocket.onmessage = null;
+      this.#websocket.onopen = null;
+      this.#websocket = null;
+    }
+
     this.#emit('disconnected');
 
     // reject all hanging requests
-    eraseRecord(this.#handlers, (handler) => handler.callback(error, undefined));
+    eraseRecord(this.#handlers, (h) => h.callback(error, undefined));
     eraseRecord(this.#waitingForId);
 
     if (this.#autoConnectMs > 0) {