您在 Redux Observable 中需要流的地方提供了 `undefined` [英] You provided `undefined` where a stream was expected in Redux Observable

问题描述

试图将我的头脑围绕在 RxJS 和 redux observable

Trying to wrap my head around RxJS and redux observable

我有这个:

export const getSomeData = (action$) =>
    action$.pipe(
        ofType(GET_USER_DATA),
        mergeMap((action) => getData(action.id)),
        map(fetchUserFulfilled),
        catchError((e) =>
            of({
                type: 'FAILED_TO_FETCH_DATA',
                e,
            }),
        ),
    )

效果很好，但现在我想在我取回数据时实际触发 2 个 observable，所以我尝试了这个:

which works good, but now I want to actually fire 2 observables when I get the data back so I tried this:

export const getSomeData = (action$) =>
    action$.pipe(
        ofType(GET_USER_DATA),
        mergeMap((action) => getData(action.id)),
        mergeMap((data) => {
            const newData = data.somethingelse
            of(fetchUserFulfilled(newData), anotherOne(newData))
        }),

        catchError((e) =>
            of({
                type: 'FAILED_TO_FETCH_DATA',
                e,
            }),
        ),
    )

但是这是失败的.那么我该如何解决这个问题，我有什么误解，我应该如何正确使用 mergeMap?

but this is failing. so how can I fix this and what misunderstanding am I having and how should I use mergeMap properly?

推荐答案

mergeMap 应该返回一个 observable

mergeMap should return an observable

mergeMap((data) => {
            const newData = data.somethingelse
            return of(fetchUserFulfilled(newData), anotherOne(newData))
        }),

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