Should I unsubscribe from Cold Observable?

Question

I know that it\'s good practice to unsubscribe from Observable to prevent memory leak.

But if it\'s Cold Observable

Answer 1

You dont need to do it because for HTTP observable is calling complete is immediately after action is done.

From source code sources i can see that on unsubscribe is called on error and on complete.

 protected _error(err: any): void {
    this.destination.error(err);
    this.unsubscribe();
  }

  protected _complete(): void {
    this.destination.complete();
    this.unsubscribe();
  }

I went further and did small experiment by adding unsubscribe with timeout

var subscription = this.http.get(`apiurl`)
            .subscribe(response => {
                setTimeout(function(){ 
                    debugger;
                    subscription.unsubscribe(); }, 30);
            });

if i step inside of unsibscribe to

 Subscriber.prototype.unsubscribe = function () {
        if (this.closed) { // this.closed is true
            return;
        }
        this.isStopped = true;
        _super.prototype.unsubscribe.call(this);
    };

Then this.closed == true, which means unsubscribe was called before.

So yes now I can say for sure you dont need to unsubscribe :)