refactor: use arrow functions as listeners

vansergen · Dec 21, 2020 · e1b592d · e1b592d
1 parent f10672c
commit e1b592d
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Showing 2 changed files with 38 additions and 50 deletions.
diff --git a/src/websocket.ts b/src/websocket.ts
@@ -408,15 +408,16 @@ export class WebsocketClient extends EventEmitter {
     await this.sendMessage({ type: "unsubscribe", subscriptions });
   }
 
-  private async sendMessage(message: MessageV2): Promise<void> {
+  private async sendMessage(data: MessageV2): Promise<void> {
+    const message = JSON.stringify(data);
     const { v2: ws } = this.sockets;
 
     if (!ws) {
       throw new Error("Websocket is not initialized");
     }
 
     await new Promise<void>((resolve, reject) => {
-      ws.send(JSON.stringify(message), (error) => {
+      ws.send(message, (error) => {
         if (error) {
           reject(error);
         } else {
@@ -431,30 +432,41 @@ export class WebsocketClient extends EventEmitter {
     url: string | URL,
     headers?: Record<string, string>
   ): Promise<void> {
-    if (this.sockets[symbol]) {
-      switch (this.sockets[symbol].readyState) {
-        case Websocket.CLOSING:
-        case Websocket.CONNECTING:
-          throw new Error(
-            `Could not connect. State: ${this.sockets[symbol].readyState}`
-          );
-        case Websocket.OPEN:
-          return;
-        default:
-          break;
-      }
+    switch (this.sockets[symbol]?.readyState) {
+      case Websocket.CLOSING:
+      case Websocket.CONNECTING:
+        throw new Error(
+          `Could not connect. State: ${this.sockets[symbol].readyState}`
+        );
+      case Websocket.OPEN:
+        return;
+      default:
+        break;
     }
 
     await new Promise<void>((resolve, reject) => {
       this.sockets[symbol] = new Websocket(url, { headers: { ...headers } });
-      this.sockets[symbol].once("open", () => {
-        resolve();
-      });
+      this.sockets[symbol].once("open", resolve);
       this.sockets[symbol].once("error", reject);
-      this.sockets[symbol].on("message", this.onMessage.bind(this, symbol));
-      this.sockets[symbol].on("open", this.onOpen.bind(this, symbol));
-      this.sockets[symbol].on("close", this.onClose.bind(this, symbol));
-      this.sockets[symbol].on("error", this.onError.bind(this, symbol));
+      this.sockets[symbol].on("message", (data: string) => {
+        try {
+          const message = JSON.parse(data) as WSMessage;
+          this.emit("message", message, symbol);
+        } catch (error) {
+          this.emit("error", error, symbol);
+        }
+      });
+      this.sockets[symbol].on("open", () => {
+        this.emit("open", symbol);
+      });
+      this.sockets[symbol].on("close", () => {
+        this.emit("close", symbol);
+      });
+      this.sockets[symbol].on("error", (error) => {
+        if (error) {
+          this.emit("error", error, symbol);
+        }
+      });
     });
   }
 
@@ -480,30 +492,6 @@ export class WebsocketClient extends EventEmitter {
     });
   }
 
-  private onMessage(symbol: string, data: string): void {
-    try {
-      const message = JSON.parse(data) as WSMessage;
-      this.emit("message", message, symbol);
-    } catch (error) {
-      this.onError(symbol, error);
-    }
-  }
-
-  private onOpen(symbol: string): void {
-    this.emit("open", symbol);
-  }
-
-  private onClose(symbol: string): void {
-    this.emit("close", symbol);
-  }
-
-  private onError(symbol: string, error: unknown): void {
-    if (!error) {
-      return;
-    }
-    this.emit("error", error, symbol);
-  }
-
   public set nonce(nonce: () => number) {
     this.#nonce = nonce;
   }

diff --git a/test/websocket.spec.ts b/test/websocket.spec.ts
@@ -639,8 +639,8 @@ suite("WebsocketClient", () => {
     await assert.rejects(client.unsubscribe(subscriptions), error);
   });
 
-  suite(".socket listeners", () => {
-    suite(".onOpen()", () => {
+  suite("socket events", () => {
+    suite("open", () => {
       test("emits `open`", async () => {
         const clientConnect = new Promise<void>((resolve, reject) => {
           client.once("open", (market) => {
@@ -666,7 +666,7 @@ suite("WebsocketClient", () => {
       });
     });
 
-    suite(".onClose()", () => {
+    suite("close", () => {
       test("emits `close`", async () => {
         const clientConnect = new Promise<void>((resolve, reject) => {
           client.once("close", (market) => {
@@ -693,7 +693,7 @@ suite("WebsocketClient", () => {
       });
     });
 
-    suite(".onError()", () => {
+    suite("error", () => {
       test("emits `error`", async () => {
         const error = new Error("Something bad happened");
         const clientConnect = new Promise<void>((resolve, reject) => {
@@ -728,7 +728,7 @@ suite("WebsocketClient", () => {
       });
     });
 
-    suite(".onMessage()", () => {
+    suite("message", () => {
       test("emits `error` on bad JSON", async () => {
         const error = new SyntaxError(
           "Unexpected token N in JSON at position 0"