Memory Leak in Angular Component Using HttpClient and Observables
I'm optimizing some code but I'm getting frustrated with I've been struggling with this for a few days now and could really use some help. I've spent hours debugging this and Hey everyone, I'm running into an issue that's driving me crazy. I've searched everywhere and can't find a clear answer. I am encountering a memory leak in my Angular application that seems to originate from a component that makes repeated HTTP requests. My component retrieves data from an API using the HttpClient and subscribes to an Observable returned from the service. I'm using Angular version 13.2.0. After navigating away from the component, I noticed that the memory usage keeps increasing, and the subscriptions aren't being cleaned up properly. Here’s a simplified version of my code: ```typescript import { Component, OnDestroy, OnInit } from '@angular/core'; import { MyDataService } from './my-data.service'; import { Subscription } from 'rxjs'; @Component({ selector: 'app-my-component', templateUrl: './my-component.component.html', }) export class MyComponent implements OnInit, OnDestroy { private dataSubscription: Subscription; public data: any; constructor(private myDataService: MyDataService) {} ngOnInit() { this.dataSubscription = this.myDataService.getData().subscribe(response => { this.data = response; }); } ngOnDestroy() { // I've tried adding this line, but it's still leaking memory this.dataSubscription.unsubscribe(); } } ``` The `getData()` function in my service retrieves data as follows: ```typescript import { Injectable } from '@angular/core'; import { HttpClient } from '@angular/common/http'; import { Observable } from 'rxjs'; @Injectable({ providedIn: 'root', }) export class MyDataService { private apiUrl = 'https://myapi.com/data'; constructor(private http: HttpClient) {} getData(): Observable<any> { return this.http.get(this.apiUrl); } } ``` Despite calling `this.dataSubscription.unsubscribe()` in the `ngOnDestroy()` lifecycle hook, memory continues to climb when I navigate away from the component and back. I also checked the Chrome DevTools for any lingering subscriptions but couldn't find any references. I've read about using `takeUntil` with a `Subject` to manage subscriptions more effectively. I implemented that approach, but the memory leak persists. Here's how I modified the code: ```typescript import { Subject } from 'rxjs'; import { takeUntil } from 'rxjs/operators'; export class MyComponent implements OnInit, OnDestroy { private destroy$ = new Subject<void>(); ngOnInit() { this.myDataService.getData() .pipe(takeUntil(this.destroy$)) .subscribe(response => { this.data = response; }); } ngOnDestroy() { this.destroy$.next(); this.destroy$.complete(); } } ``` Still, the memory leak seems to be present. Are there specific patterns or practices I might be overlooking? Any insight into how to effectively manage memory in this scenario would be greatly appreciated. I'm working on a web app that needs to handle this. What am I doing wrong? For context: I'm using Typescript on Windows. I'd really appreciate any guidance on this. This is my first time working with Typescript LTS. Thanks for any help you can provide! I'm working with Typescript in a Docker container on Windows 11. Thanks, I really appreciate it! Has anyone dealt with something similar?