fix(typings): make 'status' state slice more typesafe (#4709)

packages/netlify-cms-core/src/actions/status.ts

@@ -13,7 +13,7 @@ export const STATUS_FAILURE = 'STATUS_FAILURE';
 export function statusRequest() {
   return {
     type: STATUS_REQUEST,
-  };
+  } as const;
 }
 
 export function statusSuccess(status: {
@@ -23,21 +23,21 @@ export function statusSuccess(status: {
   return {
     type: STATUS_SUCCESS,
     payload: { status },
-  };
+  } as const;
 }
 
 export function statusFailure(error: Error) {
   return {
     type: STATUS_FAILURE,
     payload: { error },
-  };
+  } as const;
 }
 
 export function checkBackendStatus() {
   return async (dispatch: ThunkDispatch<State, {}, AnyAction>, getState: () => State) => {
     try {
       const state = getState();
-      if (state.status.get('isFetching') === true) {
+      if (state.status.get('isFetching')) {
         return;
       }
 
@@ -90,3 +90,7 @@ export function checkBackendStatus() {
     }
   };
 }
+
+export type StatusAction = ReturnType<
+  typeof statusRequest | typeof statusSuccess | typeof statusFailure
+>;

packages/netlify-cms-core/src/backend.ts

@@ -334,11 +334,11 @@ export class Backend {
       auth: { status: boolean };
       api: { status: boolean; statusPage: string };
     } = {
-      auth: { status: false },
-      api: { status: false, statusPage: '' },
+      auth: { status: true },
+      api: { status: true, statusPage: '' },
     };
     for (let i = 1; i <= attempts; i++) {
-      status = await this.implementation!.status();
+      status = await this.implementation.status();
       // return on first success
       if (Object.values(status).every(s => s.status === true)) {
         return status;

packages/netlify-cms-core/src/reducers/auth.ts

@@ -20,9 +20,9 @@ export const defaultState = fromJS({
   isFetching: false,
   user: undefined,
   error: undefined,
-});
+}) as Auth;
 
-const auth = (state = defaultState as Auth, action: AuthAction) => {
+const auth = (state = defaultState, action: AuthAction) => {
   switch (action.type) {
     case AUTH_REQUEST:
       return state.set('isFetching', true);

packages/netlify-cms-core/src/reducers/status.ts

@@ -1,16 +1,26 @@
-import { Map, fromJS } from 'immutable';
-import { AnyAction } from 'redux';
-import { STATUS_REQUEST, STATUS_SUCCESS, STATUS_FAILURE } from '../actions/status';
-import { Status } from '../types/redux';
+import { fromJS } from 'immutable';
+import { STATUS_REQUEST, STATUS_SUCCESS, STATUS_FAILURE, StatusAction } from '../actions/status';
+import { StaticallyTypedRecord } from '../types/immutable';
 
-interface StatusAction extends AnyAction {
-  payload: {
-    status: { auth: { status: boolean }; api: { status: boolean; statusPage: string } };
-    error?: Error;
-  };
-}
+export type Status = StaticallyTypedRecord<{
+  isFetching: boolean;
+  status: StaticallyTypedRecord<{
+    auth: StaticallyTypedRecord<{ status: boolean }>;
+    api: StaticallyTypedRecord<{ status: boolean; statusPage: string }>;
+  }>;
+  error: Error | undefined;
+}>;
 
-const status = (state = Map(), action: StatusAction) => {
+const defaultState = fromJS({
+  isFetching: false,
+  status: {
+    auth: { status: true },
+    api: { status: true, statusPage: '' },
+  },
+  error: undefined,
+}) as Status;
+
+const status = (state = defaultState, action: StatusAction) => {
   switch (action.type) {
     case STATUS_REQUEST:
       return state.set('isFetching', true);
@@ -30,7 +40,7 @@ const status = (state = Map(), action: StatusAction) => {
 };
 
 export const selectStatus = (status: Status) => {
-  return status.get('status')?.toJS() || {};
+  return status.get('status').toJS();
 };
 
 export default status;

packages/netlify-cms-core/src/types/immutable.ts

@@ -35,4 +35,5 @@ export interface StaticallyTypedRecord<T> {
     mapFunc: (value: T[K]) => V,
   ): StaticallyTypedRecord<{ [key: string]: V }>;
   keySeq<K extends keyof T>(): { toArray: () => K[] };
+  withMutations(mutator: (mutable: StaticallyTypedRecord<T>) => unknown): StaticallyTypedRecord<T>;
 }

packages/netlify-cms-core/src/types/redux.ts

@@ -4,6 +4,7 @@ import { Map, List, OrderedMap, Set } from 'immutable';
 import AssetProxy from '../valueObjects/AssetProxy';
 import { MediaFile as BackendMediaFile } from '../backend';
 import { Auth } from '../reducers/auth';
+import { Status } from '../reducers/status';
 
 export type SlugConfig = StaticallyTypedRecord<{
   encoding: string;
@@ -290,11 +291,6 @@ export type Search = StaticallyTypedRecord<{
 
 export type Cursors = StaticallyTypedRecord<{}>;
 
-export type Status = StaticallyTypedRecord<{
-  isFetching: boolean;
-  status: StaticallyTypedRecord<{ auth: boolean }>;
-}>;
-
 export interface State {
   auth: Auth;
   config: Config;