I'm trying to build a custom Angular 2 http request by extending the default and I'm using Ionic 2 local storage to store the auth token. (Will likely use file system in future). My issue is how to return a resolved promise from my http service so I can subscribe to the Observable within my component. I've tried Observable.fromPromise and other variations to no avail.
request(url: string|Request, options?: RequestOptionsArgs): Observable<Response> {
// Get the token used for this request.
// * Need to return this promise resolved.
var promise = this.storage.get('token').then(token => {
if (typeof url === 'string') { // meaning we have to add the token to the options, not in url
if (!options) {
// let's make option object
options = {headers: new Headers()};
}
options.headers.set('Authorization', 'Basic ' + token);
} else {
// we have to add the token to the url object
url.headers.set('Authorization', 'Basic ' + token);
}
return super.request(url, options).catch(this.catchAuthError(this));
}).catch(error => {
console.log(error);
});
}
Idea is based on this blog post, but Ionic storage returns a promise. http://www.adonespitogo.com/articles/angular-2-extending-http-provider/
I don't know if that storage returns a promise which is compatible with Rx, but if it is then the solution should look like this:
request(url: string|Request, options?: RequestOptionsArgs): Observable<Response> {
return Observable
.fromPromise(this.storage.get('token'))
.flatMap(token => {
if (typeof url === 'string') { // meaning we have to add the token to the options, not in url
if (!options) {
// let's make option object
options = {headers: new Headers()};
}
options.headers.set('Authorization', 'Basic ' + token);
} else {
// we have to add the token to the url object
url.headers.set('Authorization', 'Basic ' + token);
}
return super.request(url, options).catch(this.catchAuthError(this));
});
});
}
If promise is not compatible with observables there's still a way to do that, though it's not that elegant:
request(url: string|Request, options?: RequestOptionsArgs): Observable<Response> {
return Observable.create((observer: Observer) => {
this.storage.get('token').then(token => {
if (typeof url === 'string') { // meaning we have to add the token to the options, not in url
if (!options) {
// let's make option object
options = {headers: new Headers()};
}
options.headers.set('Authorization', 'Basic ' + token);
} else {
// we have to add the token to the url object
url.headers.set('Authorization', 'Basic ' + token);
}
super.request(url, options).catch(this.catchAuthError(this)).subscribe(result => {
observer.next(result);
observer.complete();
});
}).catch(error => {
observer.error(error);
});
});
}
