Ng-connection-service NPM

Internet Connection Monitoring Service (Angular v9-v15)

Detects whether browser has an active internet connection or not in Angular application.
Detects whether your API Server is running or not in Angular application.
Note that, this library is being updated to support most of the Angular versions. Currently, it supports Angular v9 till v15, and verified with demos. Meanwhile, for Angular 8 and earlier versions, try installing package with version 1.0.4 npm i ng-connection-service@1.0.4. Stay tuned for updates.

Install

You can get it on npm.

npm install ng-connection-service --save

Setup

Import HttpClientModule and ConnectionServiceModule into your application AppModule

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { HttpClientModule } from '@angular/common/http';
import { ConnectionServiceModule } from 'ng-connection-service';

import { AppComponent } from './app.component';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    HttpClientModule,
    ConnectionServiceModule
  ],
  bootstrap: [AppComponent]
})
export class AppModule { }

Usage - Check only internet connection status

Inject ConnectionService in Angular component's constructor, subscribe to monitor() method.

import { Component, OnDestroy, OnInit } from '@angular/core';
import { ConnectionService, ConnectionServiceOptions, ConnectionState } from 'ng-connection-service';
import { Subscription, tap } from 'rxjs';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent implements OnInit, OnDestroy {
  title = 'demo';

  status!: string;
  currentState!: ConnectionState;
  subscription = new Subscription();

  constructor(private connectionService: ConnectionService) {
  }

  ngOnInit(): void {
    this.subscription.add(
      this.connectionService.monitor(options).pipe(
        tap((newState: ConnectionState) => {
          this.currentState = newState;

          if (this.currentState.hasNetworkConnection) {
            this.status = 'ONLINE';
          } else {
            this.status = 'OFFLINE';
          }
        })
      ).subscribe()
    );
  }

  ngOnDestroy(): void {
    this.subscription.unsubscribe();
  }
}

Usage - Check YOUR API Server connection status

Inject ConnectionService in Angular component's constructor, subscribe to monitor() method. Here hasInternetConnection boolean property informs if given server URL passed via heartbeatUrl property is reachable or not.

import { Component, OnDestroy, OnInit } from '@angular/core';
import { ConnectionService, ConnectionServiceOptions, ConnectionState } from 'ng-connection-service';
import { Subscription, tap } from 'rxjs';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent implements OnInit, OnDestroy {
  title = 'demo';

  status!: string;
  currentState!: ConnectionState;
  subscription = new Subscription();

  constructor(private connectionService: ConnectionService) {
  }

  ngOnInit(): void {
    const options: ConnectionServiceOptions = {
      enableHeartbeat: false,
      heartbeatUrl: 'https://localhost:4000',
      heartbeatInterval: 2000
    }
    this.subscription.add(
      this.connectionService.monitor(options).pipe(
        tap((newState: ConnectionState) => {
          this.currentState = newState;

          if (this.currentState.hasNetworkConnection && this.currentState.hasInternetAccess) {
            this.status = 'ONLINE';
          } else {
            this.status = 'OFFLINE';
          }
        })
      ).subscribe()
    );
  }

  ngOnDestroy(): void {
    this.subscription.unsubscribe();
  }
}

Note that we have passed configuration object to monitor() function to watch application server status.

 const options: ConnectionServiceOptions = {
      enableHeartbeat: false,
      heartbeatUrl: 'https://localhost:5000',
      heartbeatInterval: 2000
    }

Demos

You can find demos in GitHub repository under directory projects/demo/.

API

You can configure the service using ConnectionServiceOptions configuration variable. Following options are available;

/**
 * Instance of this interface could be used to configure "ConnectionService".
 */
export interface ConnectionServiceOptions {
  /**
   * Controls the Internet connectivity heartbeat system. Default value is 'true'.
   */
  enableHeartbeat?: boolean;
  /**
   * Url used for checking Internet connectivity, heartbeat system periodically makes "HEAD" requests to this URL to determine Internet
   * connection status. Default value is "//internethealthtest.org".
   */
  heartbeatUrl?: string;
  /**
   * Interval used to check Internet connectivity specified in milliseconds. Default value is "30000".
   */
  heartbeatInterval?: number;
  /**
   * Interval used to retry Internet connectivity checks when an error is detected (when no Internet connection). Default value is "1000".
   */
  heartbeatRetryInterval?: number;
  /**
   * HTTP method used for requesting heartbeat Url. Default is 'head'.
   */
  requestMethod?: 'get' | 'post' | 'head' | 'options';

}