middleware get their local state

Changes

@@ -1,5 +1,10 @@
 # Revision history for Updux
 
+1.2.0 2019-11-06
+    - The middleware's 'getState' returns the local state of its updux,
+        instead of the root state. Plus we add `getRootState` to get
+        the root state.
+
 1.1.0 2019-11-05
     - Document mapping behavior of the '*' subdux.
     - add subduxUpreducer.

package.json

@@ -26,7 +26,7 @@
       "build": "tsc && typedoc",
       "test": "jest"
    },
-   "version": "1.1.0",
+   "version": "1.2.0",
    "repository": {
       "type": "git",
       "url": "git+https://github.com/yanick/updux.git"

src/buildMiddleware/index.ts

@@ -1,7 +1,7 @@
 import fp from 'lodash/fp';
 
 import { Middleware, MiddlewareAPI, Dispatch } from 'redux';
-import { Dictionary, ActionCreator, Action, UpduxDispatch } from '../types';
+import { Dictionary, ActionCreator, Action, UpduxDispatch, UpduxMiddleware } from '../types';
 
 const MiddlewareFor = (type: any, mw: Middleware ): Middleware => api => next => action => {
     if (type !== '*' && action.type !== type) return next(action);
@@ -11,12 +11,28 @@ const MiddlewareFor = (type: any, mw: Middleware ): Middleware => api => next =>
 
 type Next = (action: Action) => any;
 
+function sliceMw( slice: string, mw: Middleware ): Middleware {
+    return (api) => {
+        const getSliceState = () => fp.get(slice, api.getState() );
+        const getRootState = (api as any).getRootState || api.getState;
+        return mw({...api, getState: getSliceState, getRootState} as any )
+    };
+}
+
 function buildMiddleware<S=any>(
     effects : Dictionary<Middleware<{},S,UpduxDispatch>>= {},
     actions : Dictionary<ActionCreator>= {},
-    subMiddlewares :Middleware<{},S,UpduxDispatch>[] = [],
-): Middleware<{},S,UpduxDispatch>
+    subduxes :any = {},
+): UpduxMiddleware<S>
  {
+
+    const subMiddlewares = fp.flow(
+        fp.mapValues( fp.get('middleware') ),
+        fp.toPairs,
+        fp.filter(x=>x[1]),
+        fp.map( ([ slice, mw ]: [ string, Middleware]) => sliceMw(slice,mw) )
+    )( subduxes );
+
   return (api: MiddlewareAPI<UpduxDispatch,S>) => {
 
     for (let type in actions) {

src/middleware.test.ts

@@ -1,110 +1,142 @@
 import Updux from '.';
 import u from 'updeep';
 
-test( 'simple effect', () => {
+test('simple effect', () => {
+  const tracer = jest.fn();
 
-    const tracer = jest.fn();
-
-    const store = (new Updux({
-        effects: {
-            foo: (api:any) => (next:any) => (action:any) => {
-                tracer();
-                next(action);
-            },
-        },
-    })).createStore();
-
-    expect(tracer).not.toHaveBeenCalled();
-
-    store.dispatch({ type: 'bar' });
-
-    expect(tracer).not.toHaveBeenCalled();
-
-    store.dispatch.foo();
-
-    expect(tracer).toHaveBeenCalled();
-
-});
-
-test( 'effect and sub-effect', () => {
-
-    const tracer = jest.fn();
-
-    const tracerEffect = ( signature: string ) => ( api:any ) => (next:any) => ( action: any ) => {
-        tracer(signature);
+  const store = new Updux({
+    effects: {
+      foo: (api: any) => (next: any) => (action: any) => {
+        tracer();
         next(action);
-    };
+      },
+    },
+  }).createStore();
 
-    const store = (new Updux({
-        effects: {
-            foo: tracerEffect('root'),
-        },
-        subduxes: {
-            zzz: {effects: {
-                foo: tracerEffect('child'),
-            }
-            }
-        },
-    })).createStore();
+  expect(tracer).not.toHaveBeenCalled();
 
-    expect(tracer).not.toHaveBeenCalled();
+  store.dispatch({type: 'bar'});
 
-    store.dispatch({ type: 'bar' });
+  expect(tracer).not.toHaveBeenCalled();
 
-    expect(tracer).not.toHaveBeenCalled();
-
-    store.dispatch.foo();
-
-    expect(tracer).toHaveBeenNthCalledWith(1,'root');
-    expect(tracer).toHaveBeenNthCalledWith(2,'child');
+  store.dispatch.foo();
 
+  expect(tracer).toHaveBeenCalled();
 });
 
-test( '"*" effect', () => {
+test('effect and sub-effect', () => {
+  const tracer = jest.fn();
 
-    const tracer = jest.fn();
+  const tracerEffect = (signature: string) => (api: any) => (next: any) => (
+    action: any,
+  ) => {
+    tracer(signature);
+    next(action);
+  };
 
-    const store = (new Updux({
+  const store = new Updux({
+    effects: {
+      foo: tracerEffect('root'),
+    },
+    subduxes: {
+      zzz: {
         effects: {
-            '*': api => next => action => {
-                tracer();
-                next(action);
-            },
+          foo: tracerEffect('child'),
         },
-    })).createStore();
+      },
+    },
+  }).createStore();
 
-    expect(tracer).not.toHaveBeenCalled();
+  expect(tracer).not.toHaveBeenCalled();
 
-    store.dispatch({ type: 'bar' });
+  store.dispatch({type: 'bar'});
 
-    expect(tracer).toHaveBeenCalled();
+  expect(tracer).not.toHaveBeenCalled();
+
+  store.dispatch.foo();
+
+  expect(tracer).toHaveBeenNthCalledWith(1, 'root');
+  expect(tracer).toHaveBeenNthCalledWith(2, 'child');
 });
 
-test( 'async effect', async () => {
+test('"*" effect', () => {
+  const tracer = jest.fn();
 
-    function timeout(ms:number) {
-        return new Promise(resolve => setTimeout(resolve, ms));
-    }
+  const store = new Updux({
+    effects: {
+      '*': api => next => action => {
+        tracer();
+        next(action);
+      },
+    },
+  }).createStore();
 
-    const tracer = jest.fn();
+  expect(tracer).not.toHaveBeenCalled();
 
-    const store = (new Updux({
-        effects: {
-            foo: api => next => async action => {
-                next(action);
-                await timeout(1000);
-                tracer();
-            },
-        },
-    })).createStore();
+  store.dispatch({type: 'bar'});
 
-    expect(tracer).not.toHaveBeenCalled();
-
-    store.dispatch.foo();
-
-    expect(tracer).not.toHaveBeenCalled();
-
-    await timeout(1000);
-
-    expect(tracer).toHaveBeenCalled();
+  expect(tracer).toHaveBeenCalled();
+});
+
+test('async effect', async () => {
+  function timeout(ms: number) {
+    return new Promise(resolve => setTimeout(resolve, ms));
+  }
+
+  const tracer = jest.fn();
+
+  const store = new Updux({
+    effects: {
+      foo: api => next => async action => {
+        next(action);
+        await timeout(1000);
+        tracer();
+      },
+    },
+  }).createStore();
+
+  expect(tracer).not.toHaveBeenCalled();
+
+  store.dispatch.foo();
+
+  expect(tracer).not.toHaveBeenCalled();
+
+  await timeout(1000);
+
+  expect(tracer).toHaveBeenCalled();
+});
+
+test('getState is local', () => {
+  let childState;
+  let rootState;
+  let rootFromChild;
+
+  const child = new Updux({
+    initial: {alpha: 12},
+    effects: {
+      doIt: ({getState,getRootState}) => next => action => {
+        childState = getState();
+        rootFromChild = getRootState();
+        next(action);
+      },
+    },
+  });
+
+  const root = new Updux({
+    initial: {beta: 24},
+    subduxes: {child},
+    effects: {
+      doIt: ({getState}) => next => action => {
+        rootState = getState();
+        next(action);
+      },
+    },
+  });
+
+  const store = root.createStore();
+  store.dispatch.doIt();
+
+  expect(rootState).toEqual({beta: 24, child: {alpha: 12}});
+  expect(rootFromChild).toEqual({beta: 24, child: {alpha: 12}});
+  expect(childState).toEqual({alpha: 12});
 });

src/types.ts

@@ -178,7 +178,16 @@ export type UpduxConfig<S=any> = {
    * ```
    *
    */
-  effects?: Dictionary<Middleware<{}, S, UpduxDispatch>>;
+  effects?: Dictionary<UpduxMiddleware<S>>;
 };
 
 export type Upreducer<S = any> = (action: Action) => (state: S) => S;
+
+export interface UpduxMiddlewareAPI<S> {
+    dispatch: UpduxDispatch,
+    getState(): any,
+    getRootState(): S
+
+}
+export type UpduxMiddleware<S=any> = (api: UpduxMiddlewareAPI<S> ) => ( next: UpduxDispatch ) => ( action: Action ) => any;
+

src/updux.ts

@@ -132,12 +132,15 @@ export class Updux<S = any> {
    * A middleware aggregating all the effects defined in the
    * updux and its subduxes. Effects of the updux itself are
    * done before the subduxes effects.
+   * Note that `getState` will always return the state of the
+   * local updux. The function `getRootState` is provided
+   * alongside `getState` to get the root state.
    */
   @computed get middleware(): Middleware<{}, S, UpduxDispatch> {
     return buildMiddleware(
       this.localEffects,
       this.actions,
-      Object.values(this.subduxes).map(sd => sd.middleware),
+      this.subduxes,
     );
   }