如何使用TypeScript键入Redux-Observable的史诗动作

我在应用程序中设置TypeScript和Redux-Observable，并具有以下简单流程，我想在此处使用Epic进行应用：

dispatch('someAction')
fetch('relevant-endpoint-from-api')
getResponse(dispatch('someActionSuccess'))
failed(dispatch('someActionFailed'))

因此，按照本文的相关内容，我尝试了一下。

这是我的actions.ts文件：

export interface MediasOrigin {
  id: number;
  label: string;
  url: string;
  zonesId: number[];
  scenariosRef: number[];
  stepsRef: number[];
  gearsId: number[];
  texturesId: number[];
}

export enum MediasActionTypes {
  MEDIAS_ORIGINS_FETCH_ALL = "MEDIAS_ORIGINS_FETCH_ALL",
  MEDIAS_ORIGINS_FETCH_ALL_SUCCESS = "MEDIAS_ORIGINS_FETCH_ALL_SUCCESS",
  MEDIAS_ORIGINS_FETCH_ALL_FAILED = "MEDIAS_ORIGINS_FETCH_ALL_FAILED"
}

export interface IMediasOriginsFetchAllAction {
  type: MediasActionTypes.MEDIAS_ORIGINS_FETCH_ALL;
}

export interface IMediasOriginsFetchAllSuccessAction {
  type: MediasActionTypes.MEDIAS_ORIGINS_FETCH_ALL;
  payload: {
    medias: MediasOrigin[]
  }
}

export interface IMediasOriginsFetchAllFailedAction {
  type: MediasActionTypes.MEDIAS_ORIGINS_FETCH_ALL;
  payload: {
    error: string
  }
}

/* ACTION CREATOR */
export function fetchAllMediaOrigins(): IMediasOriginsFetchAllAction {
  return {
    type: MediasActionTypes.MEDIAS_ORIGINS_FETCH_ALL
  }
}

export type MediasAction = IMediasOriginsFetchAllAction | IMediasOriginsFetchAllSuccessAction | IMediasOriginsFetchAllFailedAction

然后我的epic.ts文件：

import { from, Observable, of } from "rxjs"
import { map, catchError, switchMap, filter } from "rxjs/operators"
import { isOfType } from "typesafe-actions"
import { Epic } from "redux-observable"

import ApiClient from "agent" // change, wrapper around superagent (http client)
import {IStore} from "reducers"
import {
  MediasAction,
  MediasActionTypes,
  IMediasOrigin
} from "./actions"

const getAllMediasOriginEpic: Epic<MediasAction, MediasAction, IStore> = action$ => {
  const request = new ApiClient();

  return action$.pipe(
    filter(isOfType(MediasActionTypes.MEDIAS_ORIGINS_FETCH_ALL)),
    switchMap(action => // change
      from(request.getAllOriginMedias()).pipe( // change
        map((response: IMediasOrigin[]) // change =>
          of({
            type: MediasActionTypes.MEDIAS_ORIGINS_FETCH_ALL_SUCCESS,
            payload: { medias: response },
          })
        ),
        catchError((error: Error) // change =>
          of({
            type: MediasActionTypes.MEDIAS_ORIGINS_FETCH_ALL_FAILED,
            payload: {error: Error.message}, // change
          })
        )
      )
    )
  )
}

export default combineEpics(getAllMediasOriginEpic)

我是TypeScript的新手，所以对于狂热者来说，错误似乎很明显，但是基于TypeScript的消息，我没有做错什么。

（不再相关）消息指向action$史诗中返回的内容：

Type 'Observable<IMediasOriginsFetchAllAction | Observable<{ type: MediasActionTypes; payload: { medias: unknown; }; }>>' is not assignable to type 'Observable<MediasAction>'.
  Type 'IMediasOriginsFetchAllAction | Observable<{ type: MediasActionTypes; payload: { medias: unknown; }; }>' is not assignable to type 'MediasAction'.
    Type 'Observable<{ type: MediasActionTypes; payload: { medias: unknown; }; }>' is not assignable to type 'MediasAction'.
      Type 'Observable<{ type: MediasActionTypes; payload: { medias: unknown; }; }>' is missing the following properties from type 'IMediasOriginsFetchAllSuccessAction': type, payload  TS2322

我没有办法解决这个问题，从消息看来，我所做的一切都是错误的，尽管MediasOrigin在接口中将其指定为数组，但媒体是未知的。我在这里想念什么吗？

有关信息，请参见以下软件包版本：

• 打字稿：4.0.2
• 可观察到的redux：1.2.0
• rxjs：6.6.3

//编辑：09/24/2020

为了简化起见，我进行了一些更改，并弄清了为什么错误消息谈论的是mediasUnknown：我没有在史诗中告诉从api调用映射的响应是MediasOrigin[]（现在重命名为IMediasOrigin []）。我也删除了api自己的自定义运算符的方法。上面的脚本中进行了更改，并带有// change注释。

现在是错误消息：

TypeScript error in /Users/utopiad/Dev/spectral-core/platform/src/components/Medias/epics.ts(11,7):
Type '(action$: ActionsObservable<MediasAction>) => Observable<Observable<{ type: MediasActionTypes; payload: { medias: IMediasOrigin[]; }; }> | { ...; }>' is not assignable to type 'Epic<MediasAction, MediasAction, IStore, any>'.
  Type 'Observable<Observable<{ type: MediasActionTypes; payload: { medias: IMediasOrigin[]; }; }> | { type: MediasActionTypes; payload: { ...; }; }>' is not assignable to type 'Observable<MediasAction>'.
    Type 'Observable<{ type: MediasActionTypes; payload: { medias: IMediasOrigin[]; }; }> | { type: MediasActionTypes; payload: { ...; }; }' is not assignable to type 'MediasAction'.
      Type 'Observable<{ type: MediasActionTypes; payload: { medias: IMediasOrigin[]; }; }>' is not assignable to type 'MediasAction'.
        Type 'Observable<{ type: MediasActionTypes; payload: { medias: IMediasOrigin[]; }; }>' is missing the following properties from type 'IMediasOriginsFetchAllFailedAction': type, payload

从我得到的结果来看，我的IMediasOriginsFetchAllSuccessAction和IMediasOriginsFetchAllFailedAction在有效负载级别之间似乎存在冲突，这使得其中之一无法分配为MediasAction类型。但这不是| |的全部目的。类型时使用运算符？