fix: simulated HTTP errors now delayed as expected (#182)

closes #180

also fixes type error (#180)

Author: wardbell

CHANGELOG.md

@@ -8,7 +8,20 @@ because this is a development tool, not a production product.
 We do try to tell you about such changes in this `CHANGELOG.md`
 and we fix bugs as fast as we can.
 
-<a id="0.5.2"></a>
+<a id="0.5.4"></a>
+## 0.5.4 (2018-03-09)
+
+Simulated HTTP error responses were not delaying the prescribed time when using RxJS `delay()`
+because it was short-circuited by the ErrorResponse.
+New `delayResponse` function does it right.
+Should not break you unless you incorrectly expected no delay for errors.
+
+Also, this library no longer calls RxJS `delay()` which may make testing with it easier
+(Angular TestBed does not handle RxJS `delay()` well because that operator uses `interval()`).
+
+Also fixes type error (issue #180).
+
+<a id="0.5.3"></a>
 ## 0.5.3 (2018-01-06)
 Can make use of `HttpParams` which yields a `request.urlWithParams`.
 Added supporting `HeroService.searchHeroes(term: string)` and test.

backend.service.js

@@ -0,0 +1,3 @@
+import { Observable } from 'rxjs/Observable';
+/** adds specified delay (in ms) to both next and error channels of the response observable */
+export declare function delayResponse<T>(response$: Observable<T>, delayMs: number): Observable<T>;

backend.service.js.map

@@ -0,0 +1 @@
+[{"__symbolic":"module","version":3,"metadata":{"delayResponse":{"__symbolic":"function","parameters":["response$","delayMs"],"value":{"__symbolic":"error","message":"Function call not supported","line":5,"character":27}}}},{"__symbolic":"module","version":1,"metadata":{"delayResponse":{"__symbolic":"function","parameters":["response$","delayMs"],"value":{"__symbolic":"error","message":"Function call not supported","line":5,"character":27}}}}]

bundles/in-memory-web-api.umd.js

@@ -1,4 +1,4 @@
-import { HttpBackend, HttpHeaders, HttpRequest, HttpResponse, HttpXhrBackend, XhrFactory } from '@angular/common/http';
+import { HttpBackend, HttpEvent, HttpHeaders, HttpRequest, HttpResponse, HttpXhrBackend, XhrFactory } from '@angular/common/http';
 import { Observable } from 'rxjs/Observable';
 import { InMemoryBackendConfigArgs, InMemoryDbService, ResponseOptions } from './interfaces';
 import { BackendService } from './backend.service';
@@ -32,7 +32,7 @@ import { BackendService } from './backend.service';
 export declare class HttpClientBackendService extends BackendService implements HttpBackend {
     private xhrFactory;
     constructor(inMemDbService: InMemoryDbService, config: InMemoryBackendConfigArgs, xhrFactory: XhrFactory);
-    handle(req: HttpRequest<any>): Observable<HttpResponse<any>>;
+    handle(req: HttpRequest<any>): Observable<HttpEvent<any>>;
     protected getJsonBody(req: HttpRequest<any>): any;
     protected getRequestMethod(req: HttpRequest<any>): string;
     protected createHeaders(headers: {

delay-response.d.ts

@@ -1,6 +1,6 @@
 {
   "name": "angular-in-memory-web-api",
-  "version": "0.5.3",
+  "version": "0.5.4",
   "description": "An in-memory web api for Angular demos and tests",
   "main": "bundles/in-memory-web-api.umd.js",
   "module": "index.js",

delay-response.js

@@ -7,10 +7,10 @@ import { fromPromise }     from 'rxjs/observable/fromPromise';
 import { isPromise }       from 'rxjs/util/isPromise';
 
 import { concatMap }       from 'rxjs/operator/concatMap';
-import { delay }           from 'rxjs/operator/delay';
 import { first }           from 'rxjs/operator/first';
 
 import { getStatusText, isSuccess, STATUS } from './http-status-codes';
+import { delayResponse } from './delay-response';
 
 import {
   HeadersCore,
@@ -160,7 +160,7 @@ export abstract class BackendService {
    */
   protected addDelay(response: Observable<any>): Observable<any> {
     const d = this.config.delay;
-    return d === 0 ? response : delay.call(response, d || 500);
+    return d === 0 ? response : delayResponse(response, d || 500);
   }
 
   /**

delay-response.js.map

@@ -0,0 +1,31 @@
+import { Observable } from 'rxjs/Observable';
+
+// Replaces use of RxJS delay. See v0.5.4.
+/** adds specified delay (in ms) to both next and error channels of the response observable */
+export function delayResponse<T>(response$: Observable<T>, delayMs: number): Observable<T> {
+  return new Observable<T>(observer => {
+    let completePending = false;
+    let nextPending = false;
+    const subscription = response$.subscribe(
+      value => {
+          nextPending = true;
+          setTimeout(() => {
+          observer.next(value);
+          if (completePending) {
+            observer.complete();
+          }
+        }, delayMs);
+      },
+      error => setTimeout(() => observer.error(error), delayMs),
+      () => {
+        completePending = true;
+        if (!nextPending) {
+          observer.complete();
+        }
+      }
+    );
+    return () => {
+      return subscription.unsubscribe();
+    };
+  });
+}

delay-response.metadata.json

@@ -73,6 +73,23 @@ describe('Http Backend Service', () => {
       );
     }));
 
+    it('GET should wait until after delay to respond', async(() => {
+      // to make test fail, set `delay=0` above
+      let gotResponse = false;
+
+      http.get('api/heroes')
+      .map(res => res.json() as Hero[])
+      .subscribe(
+        heroes => {
+          gotResponse = true;
+          expect(heroes.length).toBeGreaterThan(0, 'should have heroes');
+        },
+        failure
+      );
+
+      expect(gotResponse).toBe(false, 'should delay before response');
+    }));
+
     it('can get heroes (w/ a different base path)', async(() => {
       http.get('some-base-path/heroes')
       .map(res => res.json() as Hero[])
@@ -85,7 +102,8 @@ describe('Http Backend Service', () => {
       );
     }));
 
-    it('should 404 when GET unknown collection', async(() => {
+    it('should 404 when GET unknown collection (after delay)', async(() => {
+      let gotError = false;
       const url = 'api/unknown-collection';
       http.get(url)
       .subscribe(
@@ -94,9 +112,12 @@ describe('Http Backend Service', () => {
           fail(`should not have found data for '${url}'`);
         },
         err => {
+          gotError = true;
           expect(err.status).toBe(404, 'should have 404 status');
         }
       );
+
+      expect(gotError).toBe(false, 'should not get error until after delay');
     }));
 
     it('should return the hero w/id=1 for GET app/heroes/1', async(() => {

http-client-backend.service.d.ts

@@ -106,6 +106,21 @@ describe('HttpClient Backend Service', () => {
       );
     }));
 
+    it('GET should wait until after delay to respond', async(() => {
+      // to make test fail, set `delay=0` above
+      let gotResponse = false;
+
+      http.get<Hero[]>('api/heroes').subscribe(
+        heroes => {
+          gotResponse = true;
+          expect(heroes.length).toBeGreaterThan(0, 'should have heroes');
+        },
+        failure
+      );
+
+      expect(gotResponse).toBe(false, 'should delay before response');
+    }));
+
     it('Should only initialize the db once', async(() => {
       const httpBackend = TestBed.get(HttpBackend);
 
@@ -134,18 +149,21 @@ describe('HttpClient Backend Service', () => {
       );
     }));
 
-    it('should 404 when GET unknown collection', async(() => {
+    it('should 404 when GET unknown collection (after delay)', async(() => {
+      let gotError = false;
       const url = 'api/unknown-collection';
-      http.get<Hero[]>(url)
-      .subscribe(
+      http.get<Hero[]>(url).subscribe(
         _ => {
           console.log(_);
           fail(`should not have found data for '${url}'`);
         },
         err => {
+          gotError = true;
           expect(err.status).toBe(404, 'should have 404 status');
         }
       );
+
+      expect(gotError).toBe(false, 'should not get error until after delay');
     }));
 
     it('should return the hero w/id=1 for GET app/heroes/1', async(() => {
@@ -364,6 +382,7 @@ describe('HttpClient Backend Service', () => {
         }
       );
     }));
+
     it('should 404 when GET unknown collection', async(() => {
       const url = 'api/unknown-collection';
       http.get<Hero[]>(url)

http-client-backend.service.js.map

@@ -1,6 +1,7 @@
 import { Inject, Injectable, Optional } from '@angular/core';
 import {
   HttpBackend,
+  HttpEvent,
   HttpHeaders,
   HttpParams,
   HttpRequest,
@@ -61,7 +62,7 @@ export class HttpClientBackendService extends BackendService implements HttpBack
     super(inMemDbService, config);
   }
 
-  handle(req: HttpRequest<any>): Observable<HttpResponse<any>> {
+  handle(req: HttpRequest<any>): Observable<HttpEvent<any>> {
     try {
       return this.handleRequest(req);