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角度4:如何将应用程序级http错误作为可观察错误正确处理?

throw observable angular

1

Stéphane de Luca · 技术社区 · 8 年前

    return this.userService
        .create(user)
        .map(
            json => { 
                console.log(json);
                if (json.status=='error') {
                    console.log('error return throw');
                    return Observable.throw('Credentials mismatch or not existing');
                }

                const user = json.data as User;    
                return user;
            },
            err => { 
                console.log(err);
            }
        );

在我的歌唱中。组件,我这样做:

    onSubmit() {
        // blahblah

        this.si
        .signUp(this.credentials.emailAddress, this.credentials.password, this.credentials.zipCode)
        .subscribe(
        user => {
            console.log(user);
            console.log(`SignUpComponent.onSubmit() found user.userId ${user.userId}`);
            this.router.navigate(['signin']);
        },
        err => {
            this.errorMessage = `*** SignUpComponent: Error while signing up {err}`;
            console.error('*** SignUpComponent: Error while signing up', err);
            this.resume();
            //this.router.navigate(['signup']);
        });

        this.ngOnChanges();
    }

我希望能触发err关闭。

我错过了什么?

[Log] SigninService.signUp, zipCode=
[Log] {data: null, status: "error", message: "Error user create: - missing id   API usage v1b3: Tuâ¦ate\"}âµpost: []âµ.âµ", ws: "v1b3: Tuesday, August 25th 2017 20h20 @ Tanger"}
[Log] error return throw
[Log] ErrorObservable {_isScalar: false, error: "Credentials mismatch or not existing", scheduler: undefined, _subscribe: function, â¦}
[Log] SignUpComponent.onSubmit() found user.userId undefined

3 回复 | 直到 8 年前

1

DAG 8 年前

您正在处理用户回调中的异常,在这种情况下,这意味着它已成功执行 Observable.throws throw new Error("Credentials mismatch or not existing") 这必须取代 return Observable.throw("Credentials mismatch or not existing") ; 请看这个: How to throw error from RxJS map operator (angular)

2

0

apeshev 8 年前

throw 'Credentials mismatch or not existing' 没有回来 可观察的 部分。在执行可观察对象期间产生的任何错误都将作为当前 Observable

可观察的 这不是你想要的。

error

3

0

Stéphane de Luca 8 年前

我最终提出了以下解决方案,扩展了以下事实:1)使用throw new Error()我仍然可以返回一个可观察的,2)当Error抛出subscribe completion参数时,不触发,需要使用finally()调用,如下所示:

create(user: User): Observable<User> {
    const wsUrl = `${this.wsApi}m=create&id=${user.id}`;  // URL to web api

    return this.http.post(wsUrl, JSON.stringify(user),  { headers: this.headers })
    .retry(3)
    .map(res => {
        const json = res.json() as any;

        if (json.status=='error') throw new Error(json.message);

        return json.data as User;
    });
}

注册组件:

    onSubmit() {
        // blahblah

        this.progressing = true;

        this.si
        .signUp(this.credentials.emailAddress, this.credentials.password, this.credentials.zipCode)
        .finally(() => setTimeout(() => this.progressing = false, 1000))
        .subscribe(
            user => this.router.navigate(['signin']),
            err => this.errorMessage = err
        );

        this.ngOnChanges();
    }