Using common events

src/index.ts

@@ -2,11 +2,24 @@ import { ChildProcess, spawn } from "child_process";
 import { EventEmitter } from "events";
 import { Writable } from "stream";
 import { IOptions } from "./options";
+import { Event } from "common/events";
 
 const ef1 = "ff";
 const ef2 = "d9";
 
-export class Rtsp extends EventEmitter {
+export interface IStreamEventArgs {
+  data: Buffer;
+}
+
+export interface ICloseEventArgs {
+  message: string;
+}
+export interface IErrorEventArgs {
+  message?: string;
+  err?: Error;
+}
+
+export class Rtsp {
   private _connecteionString: string;
   private _childProcess: ChildProcess | undefined;
   private _started: boolean;
@@ -14,14 +27,20 @@ export class Rtsp extends EventEmitter {
   private _options: IOptions;
   private _paused: boolean;
 
+  private _dataEvent: Event<this, IStreamEventArgs>;
+  private _closeEvent: Event<this, ICloseEventArgs>;
+  private _errorEvent: Event<this, IErrorEventArgs>;
+
   constructor(connectionString: string, options: IOptions) {
-    super();
     this._started = false;
     this._connecteionString = connectionString;
     this._childProcess = undefined;
     this._buffer = Buffer.from("");
     this._options = options;
     this._paused = false;
+    this._dataEvent = new Event();
+    this._closeEvent = new Event();
+    this._errorEvent = new Event();
 
     this.onData = this.onData.bind(this);
   }
@@ -34,6 +53,18 @@ export class Rtsp extends EventEmitter {
     return this._paused;
   }
 
+  public get dataEvent(): Event<this, IStreamEventArgs> {
+    return this._dataEvent;
+  }
+
+  public get closeEvent(): Event<this, ICloseEventArgs> {
+    return this._closeEvent;
+  }
+
+  public get errorEvent(): Event<this, IErrorEventArgs> {
+    return this._errorEvent;
+  }
+
   public start(): void {
     const argStrings = [
       `-i ${this._connecteionString}`,
@@ -51,17 +82,24 @@ export class Rtsp extends EventEmitter {
     }
 
     this._childProcess.stdout?.on("data", this.onData);
-    this._childProcess.on("exit", this.onExit);
-    this._childProcess.on("error", this.onError);
+    this._childProcess.on("exit", (code: number, signal: NodeJS.Signals) =>
+      this._closeEvent.fire(this, {
+        message: "FFmpeg exited with code: " + code + " and signal: " + signal,
+      })
+    );
+    this._childProcess.on("error", (error: Error) =>
+      this._errorEvent.fire(this, { err: error })
+    );
 
-    if (this._childProcess.stderr) {
-      //   this._childProcess.stderr.on("data", this.onStdErrorData);
+    //Only register this event if there are subscribers
+    if (this._childProcess.stderr && this._errorEvent.length > 0) {
+      this._childProcess.stderr.on("data", this.onStdErrorData);
     }
   }
 
   public close(): void {
     this._childProcess && this._childProcess.kill("SIGKILL");
-    this.emit("closed");
+    this._closeEvent.fire(this, { message: "Process killed by user" });
   }
 
   public pause(): void {
@@ -76,10 +114,6 @@ export class Rtsp extends EventEmitter {
     return this._childProcess ? this._childProcess.stdin : null;
   }
 
-  private onError = (err: Error): void => {
-    this.emit("error", new Error("Failed to start stream: " + err.message));
-  };
-
   private onStdErrorData = (data: any): void => {
     if (!this._started) {
       this._started = true;
@@ -92,13 +126,7 @@ export class Rtsp extends EventEmitter {
         msg += `${line}\n`;
       });
 
-    this.emit("error", msg);
-  };
-
-  private onExit = (code: number, signal: NodeJS.Signals): void => {
-    const message =
-      "FFmpeg exited with code: " + code + " and signal: " + signal;
-    this.emit("closed", message);
+    this._errorEvent.fire(this, { message: msg });
   };
 
   private onData(data: Buffer): void {
@@ -111,7 +139,7 @@ export class Rtsp extends EventEmitter {
         data[data.length - 2].toString(16) == ef1 &&
         data[data.length - 1].toString(16) == ef2
       ) {
-        this.emit("data", this._buffer);
+        this._dataEvent.fire(this, { data: this._buffer });
         this._buffer = Buffer.from("");
       }
     }