Implement healthcheck service

projects/common/src/fm/components/app/app.component.ts

@@ -10,6 +10,7 @@ import { IEventMessage } from '../../models/event.message';
 import { IListItem} from '../../models/list.item';
 import { EventService } from '../../services/event.service';
 import * as  commonActions  from '../../actions/app-common.actions';
+import { HealthCheckService } from '../../services/healthcheck.service';
 
 import * as appReducers from '../../reducers/app-common.reducer';
 
@@ -46,28 +47,20 @@ export class AppComponent implements OnInit, OnDestroy {
     private meta: Meta,
     private store: Store<appReducers.State>,
     private eventService: EventService,
+    private healthCheckService: HealthCheckService
   ) {   
     
-    var connection = navigator['connection'] || navigator['mozConnection'] || navigator['webkitConnection'];
-    if(connection) {
-      this.setOnOffline(connection);
-      connection.addEventListener('change', () => {
-         this.setOnOffline(connection);
-      });      
-    }
-  }
-
-  setOnOffline(connection:any) {
-      console.debug(connection);
-      if(connection.downlink == 0) {
-        this.store.dispatch(new commonActions.Offline());
-      } else {
+    //check health every 30 seconds
+    this.healthCheckService.check(30000).subscribe((online) => {
+       if(online) {
         this.store.dispatch(new commonActions.Online());
-      }
+       } else {
+        this.store.dispatch(new commonActions.Offline());
+       }
+    });   
   }
  
 
-
   getActionFromEvent(event: IEventMessage): Action {
     var action: Action = null;
     console.debug(`${event.eventType} Event received`);

projects/common/src/fm/effects/app-common.effects.ts

@@ -165,18 +165,21 @@ export class AppCommonEffects {
     @Effect({ dispatch: false })
     online$: Observable<Action> = this.actions$.pipe(
       ofType(appCommonActions.ONLINE),
-      map((action) => {
-        console.debug("Online: Check token");
-        if(!this.oauthService$.hasValidAccessToken()) {
-          console.debug("No valid token, try to refresh");
-          if(this.oauthService$.getRefreshToken() != null ) {
-            console.debug("We have a refresh token");
-            this.oauthService$.refreshToken().then(() => {              
-              this.store$.dispatch(new appCommonActions.InitUser());
-            });
+      withLatestFrom(this.store$.select(appCommonReducers.SelectGetIsOnline)),
+      switchMap(([action,isOnline]) => {
+        if(!isOnline) {
+          console.debug("Online: Check token");
+          if(!this.oauthService$.hasValidAccessToken()) {
+            console.debug("No valid token, try to refresh");
+            if(this.oauthService$.getRefreshToken() != null ) {
+              console.debug("We have a refresh token");
+              this.oauthService$.refreshToken().then(() => {              
+                this.store$.dispatch(new appCommonActions.InitUser());
+              });
+            }
           }  
         }
-        return null;
+        return of(undefined);
       }));
 
 

projects/common/src/fm/services/healthcheck.service.ts

@@ -0,0 +1,30 @@
+import { Injectable } from '@angular/core';
+import { Observable,BehaviorSubject,of } from 'rxjs';
+import { map, catchError } from 'rxjs/operators';
+import { HttpClient, HttpXhrBackend } from "@angular/common/http";
+import { AppConfig } from "../shared/app.config";
+
+@Injectable({
+    providedIn: 'root',
+  })
+  export class HealthCheckService {
+    private httpClient: HttpClient;
+
+    constructor(xhrBackend: HttpXhrBackend, public appConfig: AppConfig) {
+        this.httpClient = new HttpClient(xhrBackend);
+    }
+  
+    ApiEndpoint() {
+      return this.appConfig.getConfig("apiEndPoint");
+    }
+
+    check(interval:number): Observable<boolean> {
+      let retval = new BehaviorSubject<boolean>(false);
+      setInterval(() => {
+        this.httpClient.get(`${this.ApiEndpoint()}/api/v1/healthcheck`).pipe(map(() => true),catchError((error) => of(false))).toPromise().then((status) => {
+           retval.next(status);
+        });
+      },interval);
+      return retval;
+    }
+}

projects/common/src/fm/shared/accesstoken.interceptor.ts

@@ -34,8 +34,6 @@ export class AccessTokenInterceptor implements HttpInterceptor {
         setHeaders: {
           Authorization: `Bearer ${this.oauthService.getAccessToken()}`
         }
-        // Please uncomment the next line if you need to connect to the backend running in Docker.
-        //, url: `http://localhost:8082${request.url}`
       });
     } else {
       this.oauthService = this.injector.get(OAuthService, null);

src/app/app.component.ts

@@ -6,4 +6,9 @@ import { Component } from '@angular/core';
 })
 export class AppRootComponent {
   title = 'FarmMaps';
+  constructor() {
+    
+    window.addEventListener('online', () => console.log('came online'));
+    window.addEventListener('offline', () => console.log('came offline'));
+  }
 }