fix(Effects): Start child effects after running root effects (#43)

This removes the app initialization logic altogether. The 'OnRunEffects'
lifecycle hook should be sufficient to control when your effects start.

Author: MikeRyanDev

modules/effects/src/effect_notification.ts

@@ -0,0 +1,58 @@
+import { Observable } from 'rxjs/Observable';
+import { Notification } from 'rxjs/Notification';
+import { Action } from '@ngrx/store';
+import { ErrorReporter } from './error_reporter';
+
+export interface EffectNotification {
+  effect: Observable<any> | (() => Observable<any>);
+  propertyName: string;
+  sourceName: string;
+  sourceInstance: any;
+  notification: Notification<Action | null | undefined>;
+}
+
+export function verifyOutput(output: EffectNotification, reporter: ErrorReporter) {
+  reportErrorThrown(output, reporter);
+  reportInvalidActions(output, reporter);
+}
+
+function reportErrorThrown(output: EffectNotification, reporter: ErrorReporter) {
+  if (output.notification.kind === 'E') {
+    const errorReason = `Effect ${getEffectName(output)} threw an error`;
+
+    reporter.report(errorReason, {
+      Source: output.sourceInstance,
+      Effect: output.effect,
+      Error: output.notification.error,
+      Notification: output.notification,
+    });
+  }
+}
+
+function reportInvalidActions(output: EffectNotification, reporter: ErrorReporter) {
+  if (output.notification.kind === 'N') {
+    const action = output.notification.value;
+    const isInvalidAction = !isAction(action);
+
+    if (isInvalidAction) {
+      const errorReason = `Effect ${getEffectName(output)} dispatched an invalid action`;
+
+      reporter.report(errorReason, {
+        Source: output.sourceInstance,
+        Effect: output.effect,
+        Dispatched: action,
+        Notification: output.notification,
+      });
+    }
+  }
+}
+
+function isAction(action: any): action is Action {
+  return action && action.type && typeof action.type === 'string';
+}
+
+function getEffectName({ propertyName, sourceInstance, sourceName }: EffectNotification) {
+  const isMethod = typeof sourceInstance[propertyName] === 'function';
+
+  return `"${sourceName}.${propertyName}${isMethod ? '()' : ''}"`;
+}

modules/effects/src/effect_sources.ts

@@ -3,17 +3,21 @@ import { mergeMap } from 'rxjs/operator/mergeMap';
 import { exhaustMap } from 'rxjs/operator/exhaustMap';
 import { map } from 'rxjs/operator/map';
 import { dematerialize } from 'rxjs/operator/dematerialize';
+import { concat } from 'rxjs/observable/concat';
 import { Observable } from 'rxjs/Observable';
 import { Subject } from 'rxjs/Subject';
-import { Injectable, isDevMode } from '@angular/core';
+import { Injectable } from '@angular/core';
 import { Action } from '@ngrx/store';
+import { EffectNotification, verifyOutput } from './effect_notification';
 import { getSourceForInstance } from './effects_metadata';
-import { resolveEffectSource, EffectNotification } from './effects_resolver';
+import { resolveEffectSource } from './effects_resolver';
 import { ErrorReporter } from './error_reporter';
 
 @Injectable()
 export class EffectSources extends Subject<any> {
-  constructor(private errorReporter: ErrorReporter) {
+  constructor(
+    private errorReporter: ErrorReporter,
+  ) {
     super();
   }
 
@@ -32,38 +36,7 @@ export class EffectSources extends Subject<any> {
           map.call(
             exhaustMap.call(source$, resolveEffectSource),
             (output: EffectNotification) => {
-              switch (output.notification.kind) {
-                case 'N': {
-                  const action = output.notification.value;
-                  const isInvalidAction =
-                    !action || !action.type || typeof action.type !== 'string';
-
-                  if (isInvalidAction) {
-                    const errorReason = `Effect "${output.sourceName}.${output.propertyName}" dispatched an invalid action`;
-
-                    this.errorReporter.report(errorReason, {
-                      Source: output.sourceInstance,
-                      Effect: output.effect,
-                      Dispatched: action,
-                      Notification: output.notification,
-                    });
-                  }
-
-                  break;
-                }
-                case 'E': {
-                  const errorReason = `Effect "${output.sourceName}.${output.propertyName}" threw an error`;
-
-                  this.errorReporter.report(errorReason, {
-                    Source: output.sourceInstance,
-                    Effect: output.effect,
-                    Error: output.notification.error,
-                    Notification: output.notification,
-                  });
-
-                  break;
-                }
-              }
+              verifyOutput(output, this.errorReporter);
 
               return output.notification;
             },

modules/effects/src/effects_feature_module.ts

@@ -1,16 +1,16 @@
 import { NgModule, Inject, Type } from '@angular/core';
-import { EffectSources } from './effect_sources';
+import { EffectsRootModule } from './effects_root_module';
 import { FEATURE_EFFECTS } from './tokens';
 
 @NgModule({})
 export class EffectsFeatureModule {
   constructor(
-    private effectSources: EffectSources,
+    private root: EffectsRootModule,
     @Inject(FEATURE_EFFECTS) effectSourceGroups: any[][],
   ) {
     effectSourceGroups.forEach(group =>
       group.forEach(effectSourceInstance =>
-        effectSources.addEffects(effectSourceInstance),
+        root.addEffects(effectSourceInstance),
       ),
     );
   }

modules/effects/src/effects_module.ts

@@ -3,9 +3,9 @@ import { EffectSources } from './effect_sources';
 import { Actions } from './actions';
 import { ROOT_EFFECTS, FEATURE_EFFECTS, CONSOLE } from './tokens';
 import { EffectsFeatureModule } from './effects_feature_module';
+import { EffectsRootModule } from './effects_root_module';
 import { EffectsRunner } from './effects_runner';
 import { ErrorReporter } from './error_reporter';
-import { RUN_EFFECTS } from './run_effects';
 
 @NgModule({})
 export class EffectsModule {
@@ -26,13 +26,12 @@ export class EffectsModule {
 
   static forRoot(rootEffects: Type<any>[]): ModuleWithProviders {
     return {
-      ngModule: EffectsModule,
+      ngModule: EffectsRootModule,
       providers: [
         EffectsRunner,
         EffectSources,
         ErrorReporter,
         Actions,
-        RUN_EFFECTS,
         rootEffects,
         {
           provide: ROOT_EFFECTS,

modules/effects/src/effects_resolver.ts

@@ -5,17 +5,10 @@ import { map } from 'rxjs/operator/map';
 import { Observable } from 'rxjs/Observable';
 import { Notification } from 'rxjs/Notification';
 import { Action } from '@ngrx/store';
+import { EffectNotification } from './effect_notification';
 import { getSourceMetadata, getSourceForInstance } from './effects_metadata';
 import { isOnRunEffects } from './on_run_effects';
 
-export interface EffectNotification {
-  effect: Observable<any> | (() => Observable<any>);
-  propertyName: string;
-  sourceName: string;
-  sourceInstance: any;
-  notification: Notification<Action | null | undefined>;
-}
-
 export function mergeEffects(
   sourceInstance: any,
 ): Observable<EffectNotification> {

modules/effects/src/effects_root_module.ts

@@ -0,0 +1,23 @@
+import { NgModule, Inject } from '@angular/core';
+import { EffectsRunner } from './effects_runner';
+import { EffectSources } from './effect_sources';
+import { ROOT_EFFECTS } from './tokens';
+
+@NgModule({})
+export class EffectsRootModule {
+  constructor(
+    private sources: EffectSources,
+    runner: EffectsRunner,
+    @Inject(ROOT_EFFECTS) rootEffects: any[],
+  ) {
+    runner.start();
+
+    rootEffects.forEach(effectSourceInstance =>
+      sources.addEffects(effectSourceInstance)
+    );
+  }
+
+  addEffects(effectSourceInstance: any) {
+    this.sources.addEffects(effectSourceInstance);
+  }
+}

modules/effects/src/on_run_effects.ts

@@ -1,6 +1,6 @@
 import { Observable } from 'rxjs/Observable';
 import { getSourceForInstance } from './effects_metadata';
-import { EffectNotification } from './effects_resolver';
+import { EffectNotification } from './effect_notification';
 
 export interface OnRunEffects {
   ngrxOnRunEffects(

modules/effects/src/run_effects.ts

@@ -3,9 +3,6 @@ import { InjectionToken, Type } from '@angular/core';
 export const IMMEDIATE_EFFECTS = new InjectionToken<any[]>(
   'ngrx/effects: Immediate Effects',
 );
-export const BOOTSTRAP_EFFECTS = new InjectionToken<any[]>(
-  'ngrx/effects: Bootstrap Effects',
-);
 export const ROOT_EFFECTS = new InjectionToken<Type<any>[]>(
   'ngrx/effects: Root Effects',
 );