Back end in memory.

Index: src/app/interceptor/in-memory-data.spec.ts
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- src/app/interceptor/in-memory-data.spec.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
+++ src/app/interceptor/in-memory-data.spec.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
@@ -0,0 +1,40 @@
+import {HTTP_INTERCEPTORS, HttpClient, HttpParams} from '@angular/common/http';
+import {HttpClientTestingModule} from '@angular/common/http/testing';
+import {TestBed} from '@angular/core/testing';
+import {InMemoryDataInterceptor} from './in-memory-data';
+import {EMethod, InMemoryDataService} from '../service/in-memory-data';
+import {testingRoute} from '../service/in-memory-data.spec';
+
+describe('In memory data interceptor', () => {
+  let httpClient: HttpClient;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [
+        InMemoryDataService,
+        {
+          provide: HTTP_INTERCEPTORS,
+          useClass: InMemoryDataInterceptor,
+          multi: true,
+        },
+      ],
+      imports: [HttpClientTestingModule]
+    });
+    httpClient = TestBed.inject(HttpClient)
+    const inMemoryData = TestBed.inject(InMemoryDataService)
+    inMemoryData.points[EMethod.POST].push(testingRoute)
+  });
+
+  it('Request intercepted', () => {
+    const params = new HttpParams()
+      .set('userId', '1234');
+    let executed = false;
+    httpClient.post('/api/test/29', { params })
+      .subscribe((data) => {
+        expect(data).toEqual('id=29&userId=1234')
+        executed = true
+      })
+      expect(executed).toEqual(true)
+  })
+
+});
Index: src/app/interceptor/in-memory-data.ts
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- src/app/interceptor/in-memory-data.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
+++ src/app/interceptor/in-memory-data.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
@@ -0,0 +1,17 @@
+import { HttpInterceptor, HttpEvent, HttpRequest, HttpHandler } from '@angular/common/http';
+import { InMemoryDataService } from '../service/in-memory-data';
+import { Observable, of } from 'rxjs';
+import {Injectable} from '@angular/core';
+
+@Injectable()
+export class InMemoryDataInterceptor implements HttpInterceptor {
+  constructor(
+    private inMemoryData: InMemoryDataService,
+  ) {}
+
+  intercept(request: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
+    const response = this.inMemoryData.process(request)
+
+    return of(response);
+  }
+}
Index: src/app/service/in-memory-data.spec.ts
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- src/app/service/in-memory-data.spec.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
+++ src/app/service/in-memory-data.spec.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
@@ -0,0 +1,49 @@
+import {TestBed} from '@angular/core/testing';
+import {HttpClient, HttpClientModule, HttpParams, HttpRequest, HttpResponse} from '@angular/common/http';
+import {EMethod, InMemoryDataService, IRoute} from './in-memory-data';
+
+export const testingRoute = {
+  pattern: /^\/api\/test\/(?<id>\d*)$/s,
+  handler(request: HttpRequest<any>, {groups}): HttpResponse<any> {
+    const id = groups['id']
+    const userId = request.body.params.get('userId')
+    return new HttpResponse<any>({
+      status: 200,
+      body: `id=${id}&userId=${userId}`
+    })
+  }
+} as IRoute<any, any>
+
+describe('In memory data', () => {
+  let httpClient: HttpClient;
+  let inMemoryData: InMemoryDataService;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      imports: [
+        HttpClientModule
+      ],
+      providers: [
+        InMemoryDataService
+      ]
+    });
+    httpClient = TestBed.inject(HttpClient)
+    inMemoryData = TestBed.inject(InMemoryDataService)
+    inMemoryData.points[EMethod.POST].push(testingRoute)
+  });
+
+  it('Test', () => {
+    const params = new HttpParams()
+      .set('userId', '1234');
+
+    const httpRequest = new HttpRequest(
+      'POST',
+      '/api/test/29',
+      { params }
+    );
+    const response = inMemoryData.process(httpRequest)
+    expect(response.status).toEqual(200)
+    expect(response.body).toEqual('id=29&userId=1234')
+  })
+
+})
Index: src/app/service/in-memory-data.ts
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- src/app/service/in-memory-data.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
+++ src/app/service/in-memory-data.ts	(revision 7e638c32329b38126ad578cb9fb0b68c86df4a76)
@@ -0,0 +1,41 @@
+import {HttpRequest, HttpResponse} from '@angular/common/http';
+
+export interface IAnswer<T> {
+  status: number
+  body: T
+}
+
+export enum EMethod {
+  GET = 'GET',
+  POST = 'POST'
+}
+
+export interface IRoute<Rq, Rs> {
+  pattern: RegExp;
+  handler<Rq, Rs>(request: HttpRequest<Rq>, match: IMatch): HttpResponse<Rs>;
+}
+
+export type IMethodPoints = {[P in EMethod]?: IRoute<any, any>[]}
+
+export interface IMatch extends Array<any> {
+  groups: Object
+}
+
+export class InMemoryDataService {
+
+  public points: IMethodPoints  = {
+    'POST': [],
+    'GET': []
+   }
+
+  process<Rq, Rs>(request: HttpRequest<Rq>): HttpResponse<Rs> {
+    const methodPoints = this.points[request.method]
+    for (const point of methodPoints) {
+      const match = request.url.match(point.pattern)
+      if (match) {
+        return point.handler(request, match)
+      }
+    }
+  }
+
+}