我正在尝试通过扩展默认值来构建自定义Angular 2 http请求,并且我正在使用Ionic 2本地存储来存储身份验证令牌. (将来可能会使用文件系统).我的问题是如何从我的http服务返回已解析的promise,以便我可以在我的组件中订阅Observable.我试过Observable.fromPromise和其他变种无济于事.
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基于这篇博客文章,但Ionic存储返回了一个承诺. http://www.adonespitogo.com/articles/angular-2-extending-http-provider/
我不知道该存储是否返回与Rx兼容的promise,但如果是,则解决方案应如下所示：
原文链接：https://www.f2er.com/angularjs/240518.htmlrequest(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));
});
});
}
如果promise与observable不兼容,那么还有一种方法可以做到这一点,尽管它并不那么优雅：
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,'Basic ' + token);
}
super.request(url,options).catch(this.catchAuthError(this)).subscribe(result => {
observer.next(result);
observer.complete();
});
}).catch(error => {
observer.error(error);
});
});
}
