Storage in Ionic not saving value into variables properly - javascript

I want to send this.data as a parameter for the post request but when I put a console.log(this.data) before the return statement, it returns both token and regNo are null values but inside the then method of storage get, console.log(this.data) gives the correct value. What is going wrong here?
import { Injectable } from "#angular/core";
import { Http } from '#angular/http';
import { Storage } from '#ionic/storage';
import 'rxjs/add/operator/toPromise';
import { DiaryModel } from './diary.model';
#Injectable()
export class DiaryService {
constructor(public http: Http, public storage: Storage) {}
data: any = {token: null, regNo: null};
getData(): Promise<DiaryModel> {
this.storage.get('regNo').then((val) => {
console.log(val);
this.data.regNo = val;
this.storage.get('user').then((val2) => {
console.log(val2);
this.data.token = val2.token;
});
});
return this.http.post("http://www.mysite.xyz/services/service.php", this.data)
.toPromise()
.then(response => response.json() as DiaryModel)
.catch(this.handleError);
}
private handleError(error: any): Promise<any> {
console.error('An error occurred', error); // for demo purposes only
return Promise.reject(error.message || error);
}
}

Ionic works as a non blocking I/O model. In your code return statement will run before getting the value from storage methods. You have to make the storage methods and return statement synchronous so return statement wait until the storage method resolves the value.
getData(): Promise<DiaryModel> {
return new Promise((resolve) =>{
data: any = {token: null, regNo: null};
this.storage.get('regNo').then((val) => {
console.log(val);
this.data.regNo = val;
this.storage.get('user').then((val2) => {
console.log(val2);
this.data.token = val2.token;
});
});
resolve(data);
});
}
returnData(): Promise<any> {
this.Data().then(res => {
return this.http.post("http://www.mysite.xyz/services/service.php", this.data)
.toPromise()
.then(response => response.json() as DiaryModel)
.catch(this.handleError);
}
}
Then you can call the returnData() method to get the return statement.

You need to chain the promises to get data sequentially. Since they are asynchronous.
Your http request is being sent before storage returns value.
I would do :
getData(): Promise<DiaryModel> {
let regPromise = this.storage.get('regNo');
let tokenPromise = this.storage.get('user');
return Promise.all([regPromise,tokenPromise]).then(values=>{
this.data.regNo=values[0];
this.data.token = values[1].token;
return this.http.post("http://www.mysite.xyz/services/service.php", this.data)
.toPromise()
.then(response => response.json() as DiaryModel)
.catch(this.handleError);
})

Related

How to get status code in angular observable

I have services below that I'd like to get status code and handle if statements in it but so far I couldn't figure it out
import { Injectable } from '#angular/core';
import { EnvService } from './env.service';
import { tap } from 'rxjs/operators';
import { Observable, from } from 'rxjs';
import { map, switchMap } from 'rxjs/operators';
import { HttpClient, HttpHeaders } from '#angular/common/http';
import { NativeStorage } from '#ionic-native/native-storage/ngx';
import { Plugins } from '#capacitor/core';
const { Storage } = Plugins;
#Injectable({
providedIn: 'root'
})
export class InvoicesServiceService {
token: any;
constructor(
private env: EnvService,
private http: HttpClient,
private nativeStorage: NativeStorage
) {
Storage.get({ key: 'token' }).then((token: any) => {
this.token = JSON.parse(token.value)
}).catch(error => console.error(error));
}
// All
getInvoices(): Observable<any> {
const tokenPromise =
this.token === undefined
? Storage.get({ key: 'token' })
: Promise.resolve(this.token);
return from(tokenPromise).pipe(
switchMap((token) => {
this.token = this.token;
const httpOptions = {
headers: new HttpHeaders({
Accept: 'application/json, text/plain',
'Content-Type': 'application/json',
Authorization: this.token.access_token,
}),
};
return this.http
.get(`${this.env.Dashboard}` + '/invoices', httpOptions)
.pipe(map((data) => data));
})
);
}
What I try to do is that if, status code is 403 redirect user to specific route other than that just return data.
any idea?
In component where you subscribe this service you can handle error
this.service
.getInvoices()
.subscribe((response) => {
// This is success
},
(error: HttpErrorResponse) => {
// Handle error
// Use if conditions to check error code, this depends on your api, how it sends error messages
});
Another way to handle in service itself.
return this.http
.get(`${this.env.Dashboard}` + '/invoices', httpOptions)
.pipe(map((data) => data))
.toPromise()
.then((response) => {
//Success
})
.catch((error: HttpErrorResponse) => {
// Handle error
});
Hope this helps.
The error is not always sent in the headers.
Sometimes the erros comes via HTML message, like when NGINX tells you someting before you even get to the backend:
<html>
<head><title>413 Request Entity Too Large</title></head>
<body>
<center><h1>413 Request Entity Too Large</h1></center>
<hr><center>nginx</center>
</body>
</html>
In these cases you should use if (error.includes('413 Request Entity Too Large')) {...}

Angular subscription on observable returns undefined

My Service
import { Injectable } from "#angular/core";
import { Observable, of } from "rxjs";
import { SearchResult } from "../Components/container-search/Models/SearchResult";
import { environment } from "../../environments/environment";
import { HttpClient, HttpHeaders } from "#angular/common/http";
#Injectable({
providedIn: "root",
})
export class ContainerService {
constructor(public http: HttpClient) {}
private SearchResults: SearchResult[] = [];
public headers = {
headers: new HttpHeaders({
"Content-Type": "application/json",
}),
};
public Search(): Observable<SearchResult[]> {
if (this.SearchResults.length === 0) {
this.http
.get<SearchResult[]>(
environment.endpointURL + "/FooBar/Search",
this.headers
)
.subscribe((x) => {
this.SearchResults = x;
return of(this.SearchResults);
});
} else {
return of(this.SearchResults);
}
}
}
When I call Search() in my component it returns
TypeError: Cannot read property 'subscribe' of undefined
My calling code is
ngOnInit(): void {
this.dataSource.paginator = this.paginator;
this.searchService.Search().subscribe((x) => {
this.dataSource = new MatTableDataSource<SearchResult>(x);
});
}
Can someone explain why this code this.searchService.Search() would always return with the above error?
The .subscribe call is returning an Observable, but that isn't what's being returned by the Search method. The subscription is an asynchronous process. The subscribe kicks off that process and only reacts when the http call returns, but the Search method keeps executing and returns undefined.
The below code will return the Observable from the http call directly and fix your issue.
import { tap } from 'rxjs/operators';
public Search(): Observable<SearchResult[]> {
if (this.SearchResults.length === 0) {
return this.http
.get<SearchResult[]>(
environment.endpointURL + "/FooBar/Search",
this.headers
).pipe(tap(x => this.SearchResults = x));
} else {
return of(this.SearchResults);
}
}

Fetching firebase data from a service

I want to fetch the user value from the firebase.service.ts in my component file.
What is the way to return the user so that they are accessible in my stats.component.ts file? How to return the value inside a then block in service so that myData variable in component.ts has the updated user value from the service.
firebase.service.ts
import { Injectable } from "#angular/core";
import { Observable as RxObservable } from "rxjs/Observable";
import { HttpClient, HttpHeaders, HttpResponse } from "#angular/common/http";
import "rxjs/add/operator/map";
import "rxjs/add/operator/do";
import * as firebase from "nativescript-plugin-firebase";
#Injectable()
export class DataService {
user= [];
constructor() { }
firebaseInit() {
firebase.init({
}).then(
() => {
// console.log("initialized");
firebase.getValue('/companies')
.then(result => {
// JSON.stringify(result) will return the json object
// result.value will get the value
console.log(JSON.stringify(result.value));
this.user = result.value;
})
.catch(error => console.log("Error:" + error));
}
).catch(
(err) => {console.log("Error is: " + err)}
)
}
sendData() {
console.log( "Outside firebaseInit" + this.user);
}
}
stats.component.ts
import { Component, OnInit,Inject } from '#angular/core';
import {DataService} from "../services/firebase.service";
#Component({
moduleId:module.id,
templateUrl: "./stats.component.html"
})
export class StatsComponent {
private mydata;
constructor(private dataService:DataService){
}
ngOnInit(){
this.mydata = this.dataService.firebaseInit();;
}
}
You can try this method in your service. You should return data in your method
service
firebaseInit() {
return firebase.init({
}).then(
() => {
// console.log("initialized");
return firebase.getValue('/companies')
.then(result => {
// JSON.stringify(result) will return the json object
// result.value will get the value
console.log(JSON.stringify(result.value));
this.user = result.value;
return this.user;
})
.catch(error => console.log("Error:" + error));
}
).catch(
(err) => {console.log("Error is: " + err)}
)
}
In your component
ngOnInit(){
this.dataService.firebaseInit().then(data => this.mydata = data);
}
You have to return every function and result inside .then function, any missing return will break the promise chain.
You can directly return result without assigning to another variable.
firebaseInit() {
return firebase.init({
}).then(
() => {
// console.log("initialized");
return firebase.getValue('/companies')
.then(result => {
// JSON.stringify(result) will return the json object
// result.value will get the value
console.log(JSON.stringify(result.value));
return result.value;
})
.catch(error => console.log("Error:" + error));
}
).catch(
(err) => {console.log("Error is: " + err)}
)
}

Angular 2 - Cannot read property '...' of undefined

Very new to Angular. I checked similar questions but they either dive into specifics or I just don't understand the solutions.
The actual error:
"Cannot read property 'idPlanet' of undefined at Object.eval [as updateRenderer] (PlanetComponent.html:11)"
The issue:
planetDetail.idPlanet is undefined most probably?
Suspect:
getPlanetDetail()
planet.component.html:
<div class="col-sm-9">
ID: {{ planetDetail.idPlanet }}
</div>
planet.component.ts:
import {
Component,
OnInit
} from '#angular/core';
import { Planet } from './planet';
import { PlanetService } from './planet.service';
#Component({
selector: 'planets',
templateUrl: './planet.component.html'
})
export class PlanetComponent implements OnInit {
private planets: Planet[];
private planetDetail: Planet;
constructor(
private planetService: PlanetService
) {}
public ngOnInit(): void {
this.getPlanetDetail();
this.getPlanets();
}
public getPlanets() {
this.planetService.getPlanets()
.subscribe(
(planets) => this.planets = planets
);
}
public getPlanetDetail() {
this.planetService.getPlanetDetail()
.subscribe(
(planets) => this.planetDetail = planets
);
}
}
planet.service.ts:
import { Injectable } from '#angular/core';
import { Headers, Http, Response } from '#angular/http';
import { Observable } from 'rxjs/Observable';
import 'rxjs/add/operator/map';
import 'rxjs/add/operator/catch';
import { Planet } from './planet';
#Injectable()
export class PlanetService {
private planetsUrl = 'http://localhost/index.php/api/planet/'; // URL to web api
// Injecting the http client into the service
constructor(private http: Http) {}
public getPlanets(): Observable<Planet[]> {
return this.http.get(this.planetsUrl + 'planets/id_sol/1')
.map(this.parseData)
.catch(this.handleError);
}
public getPlanetDetail(): Observable<Planet> {
return this.http.get(this.planetsUrl + 'planet/id_planet/1')
.map(this.parseData)
.catch(this.handleError);
}
private parseData(res: Response) {
let body = res.json();
if (body instanceof Array) {
return body || [];
} else {
return body.post || {};
}
}
private handleError(error: any): Promise<any> {
console.error('An error occurred', error); // for demo purposes only
return Promise.reject(error.message || error);
}
}
I'm at a loss tbh, I tried to build my getPlanetDetail() method from getPlanets() which works fine. Should I use a promise?
I'm having a hard time figuring out where exactly I can put console.log() to debug. I'm using angular-starter kit from Github.
Thanks for your time.
edit 1: the api outputs {"idPlanet":"1","name":"Earth"}
As the request is asynchronous sometime the value will not be fetched from the server when the page loads, therefore, the planetDetail is undefined. in order to avoid this you can use add '?' between planetDetail and idPlanet. that prints only if it has the value
ID: {{ planetDetail?.idPlanet }}
If you want to print the result or error
public getPlanetDetail() {
this.planetService.getPlanetDetail()
.subscribe(
(planets) => {
console.log(planets);
this.planetDetail = planets
},
error => {console.log(error);}
);
}
Since your response is {"idPlanet":"1","name":"Earth"}, try the following:
public getPlanetDetail(): Observable<Planet> {
return this.http.get(this.planetsUrl + 'planet/id_planet/1')
.map(res => res.json())
.catch(this.handleError);
}
my friend to debug if your 'planetDetail' is populated, just add 'console.log (planetDetail)' in the 'subscribe' method. Follow the example below.
public getPlanetDetail() {
this.planetService.getPlanetDetail()
.subscribe(
(planets) => this.planetDetail = planets
);
}
public getPlanetDetail() {
this.planetService.getPlanetDetail()
.subscribe(
(planets) => this.planetDetail = planets, (err) => (err), () => console.log(this.palnetDetail)
);
}
More about subscribe()
subscribe(function(response) {
console.log("Success Response" + response)
},
function(error) {
console.log("Error happened" + error)
},
function() {
console.log("the subscription is completed")
});

Angular 4 Interceptor retry requests after token refresh

Hi I am trying to figure out how implement the new angular interceptors and handle 401 unauthorized errors by refreshing the token and retrying the request. This is the guide I have been following: https://ryanchenkie.com/angular-authentication-using-the-http-client-and-http-interceptors
I am successfully caching the failed requests and can refresh the token but I cannot figure out how to resend the requests that previously failed. I also want to get this to work with the resolvers I am currently using.
token.interceptor.ts
return next.handle( request ).do(( event: HttpEvent<any> ) => {
if ( event instanceof HttpResponse ) {
// do stuff with response if you want
}
}, ( err: any ) => {
if ( err instanceof HttpErrorResponse ) {
if ( err.status === 401 ) {
console.log( err );
this.auth.collectFailedRequest( request );
this.auth.refreshToken().subscribe( resp => {
if ( !resp ) {
console.log( "Invalid" );
} else {
this.auth.retryFailedRequests();
}
} );
}
}
} );
authentication.service.ts
cachedRequests: Array<HttpRequest<any>> = [];
public collectFailedRequest ( request ): void {
this.cachedRequests.push( request );
}
public retryFailedRequests (): void {
// retry the requests. this method can
// be called after the token is refreshed
this.cachedRequests.forEach( request => {
request = request.clone( {
setHeaders: {
Accept: 'application/json',
'Content-Type': 'application/json',
Authorization: `Bearer ${ this.getToken() }`
}
} );
//??What to do here
} );
}
The above retryFailedRequests() file is what I can't figure out. How do I resend the requests and make them available to the route through the resolver after retrying?
This is all the relevant code if that helps: https://gist.github.com/joshharms/00d8159900897dc5bed45757e30405f9
My final solution. Works with parallel requests.
UPDATE: The code updated with Angular 9 / RxJS 6, error handling and fix looping when refreshToken fails
import { HttpRequest, HttpHandler, HttpInterceptor, HTTP_INTERCEPTORS } from "#angular/common/http";
import { Injector } from "#angular/core";
import { Router } from "#angular/router";
import { Subject, Observable, throwError } from "rxjs";
import { catchError, switchMap, tap} from "rxjs/operators";
import { AuthService } from "./auth.service";
export class AuthInterceptor implements HttpInterceptor {
authService;
refreshTokenInProgress = false;
tokenRefreshedSource = new Subject();
tokenRefreshed$ = this.tokenRefreshedSource.asObservable();
constructor(private injector: Injector, private router: Router) {}
addAuthHeader(request) {
const authHeader = this.authService.getAuthorizationHeader();
if (authHeader) {
return request.clone({
setHeaders: {
"Authorization": authHeader
}
});
}
return request;
}
refreshToken(): Observable<any> {
if (this.refreshTokenInProgress) {
return new Observable(observer => {
this.tokenRefreshed$.subscribe(() => {
observer.next();
observer.complete();
});
});
} else {
this.refreshTokenInProgress = true;
return this.authService.refreshToken().pipe(
tap(() => {
this.refreshTokenInProgress = false;
this.tokenRefreshedSource.next();
}),
catchError(() => {
this.refreshTokenInProgress = false;
this.logout();
}));
}
}
logout() {
this.authService.logout();
this.router.navigate(["login"]);
}
handleResponseError(error, request?, next?) {
// Business error
if (error.status === 400) {
// Show message
}
// Invalid token error
else if (error.status === 401) {
return this.refreshToken().pipe(
switchMap(() => {
request = this.addAuthHeader(request);
return next.handle(request);
}),
catchError(e => {
if (e.status !== 401) {
return this.handleResponseError(e);
} else {
this.logout();
}
}));
}
// Access denied error
else if (error.status === 403) {
// Show message
// Logout
this.logout();
}
// Server error
else if (error.status === 500) {
// Show message
}
// Maintenance error
else if (error.status === 503) {
// Show message
// Redirect to the maintenance page
}
return throwError(error);
}
intercept(request: HttpRequest<any>, next: HttpHandler): Observable<any> {
this.authService = this.injector.get(AuthService);
// Handle request
request = this.addAuthHeader(request);
// Handle response
return next.handle(request).pipe(catchError(error => {
return this.handleResponseError(error, request, next);
}));
}
}
export const AuthInterceptorProvider = {
provide: HTTP_INTERCEPTORS,
useClass: AuthInterceptor,
multi: true
};
With the latest version of Angular (7.0.0) and rxjs (6.3.3), this is how I created a fully functional Auto Session recovery interceptor ensuring, if concurrent requests fail with 401, then also, it should only hit token refresh API once and pipe the failed requests to the response of that using switchMap and Subject. Below is how my interceptor code looks like. I have omitted the code for my auth service and store service as they are pretty standard service classes.
import {
HttpErrorResponse,
HttpEvent,
HttpHandler,
HttpInterceptor,
HttpRequest
} from "#angular/common/http";
import { Injectable } from "#angular/core";
import { Observable, Subject, throwError } from "rxjs";
import { catchError, switchMap } from "rxjs/operators";
import { AuthService } from "../auth/auth.service";
import { STATUS_CODE } from "../error-code";
import { UserSessionStoreService as StoreService } from "../store/user-session-store.service";
#Injectable()
export class SessionRecoveryInterceptor implements HttpInterceptor {
constructor(
private readonly store: StoreService,
private readonly sessionService: AuthService
) {}
private _refreshSubject: Subject<any> = new Subject<any>();
private _ifTokenExpired() {
this._refreshSubject.subscribe({
complete: () => {
this._refreshSubject = new Subject<any>();
}
});
if (this._refreshSubject.observers.length === 1) {
this.sessionService.refreshToken().subscribe(this._refreshSubject);
}
return this._refreshSubject;
}
private _checkTokenExpiryErr(error: HttpErrorResponse): boolean {
return (
error.status &&
error.status === STATUS_CODE.UNAUTHORIZED &&
error.error.message === "TokenExpired"
);
}
intercept(
req: HttpRequest<any>,
next: HttpHandler
): Observable<HttpEvent<any>> {
if (req.url.endsWith("/logout") || req.url.endsWith("/token-refresh")) {
return next.handle(req);
} else {
return next.handle(req).pipe(
catchError((error, caught) => {
if (error instanceof HttpErrorResponse) {
if (this._checkTokenExpiryErr(error)) {
return this._ifTokenExpired().pipe(
switchMap(() => {
return next.handle(this.updateHeader(req));
})
);
} else {
return throwError(error);
}
}
return caught;
})
);
}
}
updateHeader(req) {
const authToken = this.store.getAccessToken();
req = req.clone({
headers: req.headers.set("Authorization", `Bearer ${authToken}`)
});
return req;
}
}
As per #anton-toshik comment, I thought it's a good idea to explain the functioning of this code in a write-up. You can have a read at my article here for the explanation and understanding of this code (how and why it works?). Hope it helps.
I had to solve the following requirements:
✅ Refresh token only once for multiple requests
✅ Log out user if refreshToken failed
✅ Log out if user gets an error after first refreshing
✅ Queue all requests while token is being refreshed
As a result I've collected different options in order to refresh token in Angular:
Brute force solution with tokenRefreshed$ BehaviorSubject as a semaphore
Using caught parameter in catchError RxJS operator to retry request failed request
intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
let retries = 0;
return this.authService.token$.pipe(
map(token => req.clone({ setHeaders: { Authorization: `Bearer ${token}` } })),
concatMap(authReq => next.handle(authReq)),
// Catch the 401 and handle it by refreshing the token and restarting the chain
// (where a new subscription to this.auth.token will get the latest token).
catchError((err, restart) => {
// If the request is unauthorized, try refreshing the token before restarting.
if (err.status === 401 && retries === 0) {
retries++;
return concat(this.authService.refreshToken$, restart);
}
if (retries > 0) {
this.authService.logout();
}
return throwError(err);
})
);
}
Using retryWhen RxJS operator
intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
return this.authService.token$.pipe(
map(token => req.clone({ setHeaders: { Authorization: `Bearer ${token}` } })),
concatMap(authReq => next.handle(authReq)),
retryWhen((errors: Observable<any>) => errors.pipe(
mergeMap((error, index) => {
// any other error than 401 with {error: 'invalid_grant'} should be ignored by this retryWhen
if (error.status !== 401) {
return throwError(error);
}
if (index === 0) {
// first time execute refresh token logic...
return this.authService.refreshToken$;
}
this.authService.logout();
return throwError(error);
}),
take(2)
// first request should refresh token and retry,
// if there's still an error the second time is the last time and should navigate to login
)),
);
}
All these options are horoughly tested and can be found in angular-refresh-token github repo
See also:
catchError - RxJS Reference
Andrei Ostrovski's final solution works really well, but does not work if the refresh token is also expired (assuming you're making an api call to refresh). After some digging, I realised that the refresh token API call was also intercepted by the interceptor. I've had to add an if statement to handle this.
intercept( request: HttpRequest<any>, next: HttpHandler ):Observable<any> {
this.authService = this.injector.get( AuthenticationService );
request = this.addAuthHeader(request);
return next.handle( request ).catch( error => {
if ( error.status === 401 ) {
// The refreshToken api failure is also caught so we need to handle it here
if (error.url === environment.api_url + '/refresh') {
this.refreshTokenHasFailed = true;
this.authService.logout();
return Observable.throw( error );
}
return this.refreshAccessToken()
.switchMap( () => {
request = this.addAuthHeader( request );
return next.handle( request );
})
.catch((err) => {
this.refreshTokenHasFailed = true;
this.authService.logout();
return Observable.throw( err );
});
}
return Observable.throw( error );
});
}
I ran into a similar problem as well and I think the collect/retry logic is overly complicated. Instead, we can just use the catch operator to check for the 401, then watch for the token refresh, and rerun the request:
return next.handle(this.applyCredentials(req))
.catch((error, caught) => {
if (!this.isAuthError(error)) {
throw error;
}
return this.auth.refreshToken().first().flatMap((resp) => {
if (!resp) {
throw error;
}
return next.handle(this.applyCredentials(req));
});
}) as any;
...
private isAuthError(error: any): boolean {
return error instanceof HttpErrorResponse && error.status === 401;
}
Based on this example, here's my piece
#Injectable({
providedIn: 'root'
})
export class AuthInterceptor implements HttpInterceptor {
constructor(private loginService: LoginService) { }
/**
* Intercept request to authorize request with oauth service.
* #param req original request
* #param next next
*/
intercept(req: HttpRequest<any>, next: HttpHandler): Observable<any> {
const self = this;
if (self.checkUrl(req)) {
// Authorization handler observable
const authHandle = defer(() => {
// Add authorization to request
const authorizedReq = req.clone({
headers: req.headers.set('Authorization', self.loginService.getAccessToken()
});
// Execute
return next.handle(authorizedReq);
});
return authHandle.pipe(
catchError((requestError, retryRequest) => {
if (requestError instanceof HttpErrorResponse && requestError.status === 401) {
if (self.loginService.isRememberMe()) {
// Authrozation failed, retry if user have `refresh_token` (remember me).
return from(self.loginService.refreshToken()).pipe(
catchError((refreshTokenError) => {
// Refresh token failed, logout
self.loginService.invalidateSession();
// Emit UserSessionExpiredError
return throwError(new UserSessionExpiredError('refresh_token failed'));
}),
mergeMap(() => retryRequest)
);
} else {
// Access token failed, logout
self.loginService.invalidateSession();
// Emit UserSessionExpiredError
return throwError(new UserSessionExpiredError('refresh_token failed'));
}
} else {
// Re-throw response error
return throwError(requestError);
}
})
);
} else {
return next.handle(req);
}
}
/**
* Check if request is required authentication.
* #param req request
*/
private checkUrl(req: HttpRequest<any>) {
// Your logic to check if the request need authorization.
return true;
}
}
You may want to check if user enabled Remember Me to use refresh token for retrying or just redirect to logout page.
Fyi, the LoginService has the following methods:
- getAccessToken(): string - return the current access_token
- isRememberMe(): boolean - check if user have refresh_token
- refreshToken(): Observable / Promise - Request to oauth server for new access_token using refresh_token
- invalidateSession(): void - remove all user info and redirect to logout page
Ideally, you want to check isTokenExpired before request sent. And if expired refresh the token and add refreshed in the header.
Other than that retry operator may help with your logic of refreshing token on 401 response.
Use the RxJS retry operator in your service where you are making a request. It accepts a retryCount argument.
If not provided, it will retry the sequence indefinitely.
In your interceptor on response refresh the token and return the error. When your service gets back the error but now retry operator is being used so it will retry the request and this time with the refreshed token(Interceptor uses refreshed token to add in the header.)
import {HttpClient} from '#angular/common/http';
import { Injectable } from '#angular/core';
import { Observable } from 'rxjs/Rx';
#Injectable()
export class YourService {
constructor(private http: HttpClient) {}
search(params: any) {
let tryCount = 0;
return this.http.post('https://abcdYourApiUrl.com/search', params)
.retry(2);
}
}
On the most accepted answer by Andrei Ostrovski, people comment about memory leak when token refresh request fails for some reason. One could mitigate this by using RxJS timeout operator, like this:
//...
tokenRefreshTimeout = 60000;
//...
// Invalid token error
else if (error.status === 401) {
return this.refreshToken().pipe(
timeout(this.tokenRefreshTimeout), //added timeout here
switchMap(() => {
request = this.addAuthHeader(request);
return next.handle(request);
}),
//...
(sorry, I don't have enough rep to comment, also I cannot suggest an edit because the edit queue is always full)
To support ES6 syntax the solution needs to be bit modify and that is as following also included te loader handler on multiple request
private refreshTokenInProgress = false;
private activeRequests = 0;
private tokenRefreshedSource = new Subject();
private tokenRefreshed$ = this.tokenRefreshedSource.asObservable();
private subscribedObservable$: Subscription = new Subscription();
intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
if (this.activeRequests === 0) {
this.loaderService.loadLoader.next(true);
}
this.activeRequests++;
// Handle request
request = this.addAuthHeader(request);
// NOTE: if the flag is true it will execute retry auth token mechanism ie. by using refresh token it will fetch new auth token and will retry failed api with new token
if (environment.retryAuthTokenMechanism) {
// Handle response
return next.handle(request).pipe(
catchError(error => {
if (this.authenticationService.refreshShouldHappen(error)) {
return this.refreshToken().pipe(
switchMap(() => {
request = this.addAuthHeader(request);
return next.handle(request);
}),
catchError(() => {
this.authenticationService.setInterruptedUrl(this.router.url);
this.logout();
return EMPTY;
})
);
}
return EMPTY;
}),
finalize(() => {
this.hideLoader();
})
);
} else {
return next.handle(request).pipe(
catchError(() => {
this.logout();
return EMPTY;
}),
finalize(() => {
this.hideLoader();
})
);
}
}
ngOnDestroy(): void {
this.subscribedObservable$.unsubscribe();
}
/**
* #description Hides loader when all request gets complete
*/
private hideLoader() {
this.activeRequests--;
if (this.activeRequests === 0) {
this.loaderService.loadLoader.next(false);
}
}
/**
* #description set new auth token by existing refresh token
*/
private refreshToken() {
if (this.refreshTokenInProgress) {
return new Observable(observer => {
this.subscribedObservable$.add(
this.tokenRefreshed$.subscribe(() => {
observer.next();
observer.complete();
})
);
});
} else {
this.refreshTokenInProgress = true;
return this.authenticationService.getNewAccessTokenByRefreshToken().pipe(tap(newAuthToken => {
this.authenticationService.updateAccessToken(newAuthToken.access_token);
this.refreshTokenInProgress = false;
this.tokenRefreshedSource.next();
}));
}
}
private addAuthHeader(request: HttpRequest<any>) {
const accessToken = this.authenticationService.getAccessTokenOnly();
return request.clone({
setHeaders: {
Authorization: `Bearer ${accessToken}`
}
});
}
/**
* #todo move in common service or auth service once tested
* logout and redirect to login
*/
private logout() {
this.authenticationService.removeSavedUserDetailsAndLogout();
}
My Answer
In this case just handler 401
#Injectable()
export class AuthHttpInterceptor implements HttpInterceptor {
logoutUser$ = defer(() => (this.authService.logout(), EMPTY));
refresh$ = defer(() => this.authService.refreshTokenFromServer()).pipe(catchError(() => this.logoutUser$), share());
constructor(private authService: AuthService) { }
private applyCredentials(request: HttpRequest<any>): HttpRequest<any> {
return request.clone({
setHeaders: { Authorization: 'Bearer ' + this.authService.accessToken }
});
}
public intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
if (InterceptorSkipHeader.checkHeader(request)) {
const req = InterceptorSkipHeader.deleteHeader(request);
return next.handle(req);
}
const nextHandle$ = defer(() => next.handle(this.applyCredentials(request)));
return iif(() => this.authService.tokenIsEmpty, this.logoutUser$, nextHandle$).pipe(this.httpErrorsHandler());
}
httpErrorsHandler() {
return (source$: Observable<any>) => source$.pipe(
catch401Error(() => this.handle401Error(source$)),
catch400Error((err) => EMPTY),
catch403Error((err) => EMPTY),
catch406Error((err) => EMPTY),
catch500Error((err) => EMPTY),
);
}
handle401Error(retry$: Observable<any>): Observable<any> {
return retry$.pipe(
startWhen(this.refresh$),
takeUntil(this.authService.logout$),
catch401Error(() => this.logoutUser$),
);
}
}
full code ( auth-http-interceptor.ts )
step 1, Create two Observable
logoutUser$ :
use defer() do your logout logic (like clear token from LocalStorage) and retun EMPTY
refresh$ :
use defer create refresh$ Observable, make it always take new refresh token to call refresh API
logout on catch error
share() this Observable(make all 401 wait same refresh API back)
logoutUser$ = defer(() => (this.authService.logout(), EMPTY));
refresh$ = defer(() => this.authService.refreshTokenFromServer()).pipe(catchError(() => this.logoutUser$), share());
step 2, Skip interceptor
just make api skip interceptor ( uitls.ts )
class Xheader {
static readonly interceptorSkipHeader = new Xheader('interceptorSkipHeader');
readonly headers = { [this.headerName]: this.headerName };
readonly options = { headers: this.headers };
private constructor(readonly headerName: string) { }
public checkHeader({ headers }: HttpRequest<any>) {
return headers.has(this.headerName);
}
public deleteHeader(request: HttpRequest<any>) {
return request.clone({ headers: request.headers.delete(this.headerName) });
}
}
export const InterceptorSkipHeader = Xheader.interceptorSkipHeader;
like this InterceptorSkipHeader.options ( auth.service.ts)
refreshTokenFromServer(): Observable<Token> {
return this.http.post<Token>(this.authApi + '/refreshToken', this.token, InterceptorSkipHeader.options).pipe(setTokenToLocalStorage());
}
step 3, Interceptor
Has skip header InterceptorSkipHeader.checkHeader(request)
delete and return without handler
Else, handler
create nextHandle$ with access token : applyCredentials(request) use defer() ( always take new access token )
use iif() check if token is empty will logoutUser$, else nextHandle$
add httpErrorsHandler() operator, handler this stream
public intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
if (InterceptorSkipHeader.checkHeader(request)) {
const req = InterceptorSkipHeader.deleteHeader(request);
return next.handle(req);
}
const nextHandle$ = defer(() => next.handle(this.applyCredentials(request)));
return iif(() => this.authService.tokenIsEmpty, this.logoutUser$, nextHandle$).pipe(this.httpErrorsHandler());
}
Add access token function
private applyCredentials(request: HttpRequest<any>): HttpRequest<any> {
return request.clone({
setHeaders: { Authorization: 'Bearer ' + this.authService.accessToken }
});
}
step 4, Custom operator
We should create some custom operator before error Handler
catchHttpError operator
In this case we just handler 401
catch401Error : catch http 401
catch400Error : catch http 400
catch403Error : catch http 403
catch406Error : catch http 406
catch500Error : catch http 500
function catchHttpError(...status: Array<number>) {
const statusMap = status.reduce((m, v) => m.set(v, v), new Map());
return (next: (err: HttpErrorResponse) => Observable<any>) => {
return catchError((err) => err instanceof HttpErrorResponse && statusMap.has(err.status) ? next(err) : throwError(err));
};
}
const catch401Error = catchHttpError(401);
const catch400Error = catchHttpError(400);
const catch403Error = catchHttpError(403);
const catch406Error = catchHttpError(406);
const catch500Error = catchHttpError(500);
startWhen operator (uitls.ts)
equal delayWhen() second parameter (subscriptionDelay)
export function startWhen<T>(subscriptionDelay: Observable<any>) {
return (source$: Observable<T>) => concat(subscriptionDelay.pipe(take(1), ignoreElements()), source$);
}
step 5, Http error handler
In this case we just handler 401
catch401Error must be the first (make sure other error handler will catch retry API error)
handle401Error(source$) will retry source$ (previous Observable)
httpErrorsHandler() {
return (source$: Observable<any>) => source$.pipe(
catch401Error(() => this.handle401Error(source$)),
catch400Error((err) => EMPTY),
catch403Error((err) => EMPTY),
catch406Error((err) => EMPTY),
catch500Error((err) => EMPTY),
);
}
handle401Error
startWhen() : retry$ will wait refresh$ complete than call retry API
In process, if authService.logout$ trigger will stop stream (unsubscribe)
If retry API still 401 error will logout user
handle401Error(retry$: Observable<any>): Observable<any> {
return retry$.pipe(
startWhen(this.refresh$),
takeUntil(this.authService.logout$),
catch401Error(() => this.logoutUser$),
);
}
https://medium.com/#eddylin1937/angular-interceptor-with-rxjs-refresh-token-176326c84a36
After api failed with HTTP Error 401 ,token-refresh api got called , all your failed and cached request can be retried using http interceptor.
if (this.isRefreshingToken && !req.url.endsWith(tokenURL)) {
// check if unique url to be added in cachedRequest
if (urlPresentIndex == -1) {
this.cachedRequests.push(req);
return this.tokenSubject.pipe(
switchMap(() => next.handle(req)),
tap((v) => {
// delete request from catchedRequest if api gets called
this.cachedRequests.splice(
this.cachedRequests.findIndex(
(httpRequest) => httpRequest.url == req.url
),
1
);
return EMPTY;
})
);
} else {
//already in cached request array
return EMPTY;
}
}
For more details you can read my medium article Token-Refresh-Interceptor-retry-failed-Requests
Check it out, how it works stackblitz
I got this creating a new request based on the url of the failed request and sending the same body of the failed request.
retryFailedRequests() {
this.auth.cachedRequests.forEach(request => {
// get failed request body
var payload = (request as any).payload;
if (request.method == "POST") {
this.service.post(request.url, payload).subscribe(
then => {
// request ok
},
error => {
// error
});
}
else if (request.method == "PUT") {
this.service.put(request.url, payload).subscribe(
then => {
// request ok
},
error => {
// error
});
}
else if (request.method == "DELETE")
this.service.delete(request.url, payload).subscribe(
then => {
// request ok
},
error => {
// error
});
});
this.auth.clearFailedRequests();
}
In your authentication.service.ts, you should have a HttpClient injected as a dependency
constructor(private http: HttpClient) { }
You can then re-submit the request (inside retryFailedRequests) as follow:
this.http.request(request).subscribe((response) => {
// You need to subscribe to observer in order to "retry" your request
});

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