client pop-up error management

src/app/app.component.html

@@ -1,33 +1,27 @@
 <h1>Angular CLI to UI</h1>
 
-<ng-container *ngIf="isAlive">
-    <ng-container *ngIf="isReadyForWork">
-        <app-new
-            *ngIf="!isAngularProject"
-            (sendCommand)="sendCommand($event)"
-            (changeAngularProjectStatus)="checkAngularProject($event)"
-            >
-        </app-new>
-
-        <ng-container *ngIf="isAngularProject">
-            <app-serve (sendCommand)="sendCommand($event)"></app-serve>
-            <app-generate (sendCommand)="sendCommand($event)"></app-generate>
-            <button
-                (click)="leaveProject()"
-                [disabled]="!isProjectLeavable">
-                Leave Project
-            </button>
-            <div *ngIf="!isProjectLeavable">Can not leave this project</div>
-        </ng-container>
-    </ng-container>
+<app-popup-error></app-popup-error>
 
-    <ng-container
-        *ngIf="!isReadyForWork"
-        class="blocker">
-        Please wait while the server is loading
+<ng-container *ngIf="isReadyForWork">
+    <app-new
+        *ngIf="!isAngularProject"
+        (sendCommand)="sendCommand($event)"
+        (changeAngularProjectStatus)="checkAngularProject($event)"
+        >
+    </app-new>
+
+    <ng-container *ngIf="isAngularProject">
+        <app-serve (sendCommand)="sendCommand($event)"></app-serve>
+        <app-generate (sendCommand)="sendCommand($event)"></app-generate>
+        <button
+            (click)="leaveProject()">
+            Leave Project
+        </button>
     </ng-container>
 </ng-container>
 
-<ng-container *ngIf="!isAlive">
-    The server is offline, please run the server and restart the client
+<ng-container
+    *ngIf="!isReadyForWork"
+    class="blocker">
+    Please wait while the server is loading
 </ng-container>

src/app/app.component.ts

@@ -1,10 +1,12 @@
 import { Component, OnInit } from '@angular/core';
 
-import { interval } from 'rxjs';
+import { interval, timer } from 'rxjs';
+import { exhaustMap } from 'rxjs/operators';
 
 import { CommandService } from './services/command/command.service';
 import { CommandRequest } from './models/angular-command-request';
 import { AngularCliProcessStatus } from './models/angular-cli-process-status.enum';
+import { ErrorService } from './services/error/error.service';
 
 @Component({
   selector: 'app-root',
@@ -18,11 +20,13 @@ export class AppComponent implements OnInit {
   isReadyForWork = false;
   runningCommands = {};
   timedStatusCheck = interval(1000);
+  KEEP_ALIVE_INTERVAL = 1000;
   subscription = {};
-  isAlive = true;
-  isProjectLeavable = true;
 
-  constructor(private commandService: CommandService) {}
+  constructor(
+    private commandService: CommandService,
+    private errorService: ErrorService
+  ) {}
 
   ngOnInit() {
     this.keepAlive();
@@ -78,24 +82,34 @@ export class AppComponent implements OnInit {
   }
 
   keepAlive(): void {
-    this.subscription['keepAlive'] = this.timedStatusCheck
-      .subscribe(() => {
-        this.commandService.keepAlive()
-          .subscribe( response => {
-            this.isAlive = true;
-          }, error => {
-            this.isAlive = false;
-            this.subscription['keepAlive'].unsubscribe();
+    this.subscription['TimedkeepAlive'] = timer(0, this.KEEP_ALIVE_INTERVAL)
+      .pipe(
+        exhaustMap(
+          () => this.commandService.keepAlive()
+        )
+      )
+      .subscribe(
+        response => {},
+        error => {
+          this.errorService.addError({
+            errorText: 'The server is offline',
+            errorDescription: 'please run the server and restart the client'
           });
-      });
-    }
+          this.subscription['TimedkeepAlive'].unsubscribe();
+        }
+      );
+  }
 
   leaveProject(): void {
     this.commandService.leaveProject()
       .subscribe(
         () => this.checkAngularProject(),
-        () => this.isProjectLeavable = false
-      );
+        () => {
+          this.errorService.addError({
+            errorText: 'Unable to leave this project',
+            errorDescription: 'To run ngWiz on another project or to create a new one, please run it in the apropriate project direcroty'
+          });
+        });
   }
 
   sendCommand(userCommand: string): void {
@@ -107,5 +121,4 @@ export class AppComponent implements OnInit {
         .subscribe(() => this.startCheckingCommand(commandId));
     });
   }
-
 }

src/app/app.module.ts

@@ -8,14 +8,16 @@ import { NewComponent } from './components/new/new.component';
 import { ServeComponent } from './components/serve/serve.component';
 import { GenerateComponent } from './components/generate/generate.component';
 import { CommandService } from './services/command/command.service';
+import { PopupErrorComponent } from './components/popup-error/popup-error.component';
 
 
 @NgModule({
   declarations: [
     AppComponent,
     ServeComponent,
     NewComponent,
-    GenerateComponent
+    GenerateComponent,
+    PopupErrorComponent
   ],
   imports: [
     FormsModule,

src/app/components/popup-error/popup-error.component.css

@@ -0,0 +1,3 @@
+.error {
+  color: red;
+}

src/app/components/popup-error/popup-error.component.html

@@ -0,0 +1,12 @@
+<div
+  *ngFor="let error of getErrors()"
+  class="error">
+    {{error.errorText}}
+    <ng-container
+      *ngIf="error.handleFunction"
+      class="userSelection">
+        <button (click)="handleError(error)">Yes</button>
+        <button (click)="clearError(error)">No</button>
+    </ng-container>
+    <button *ngIf="!error.handleFunction" (click)="clearError(error)">Ok</button>
+</div>

src/app/components/popup-error/popup-error.component.spec.ts

@@ -0,0 +1,25 @@
+import { async, ComponentFixture, TestBed } from '@angular/core/testing';
+
+import { PopupErrorComponent } from './popup-error.component';
+
+describe('PopupErrorComponent', () => {
+  let component: PopupErrorComponent;
+  let fixture: ComponentFixture<PopupErrorComponent>;
+
+  beforeEach(async(() => {
+    TestBed.configureTestingModule({
+      declarations: [ PopupErrorComponent ]
+    })
+    .compileComponents();
+  }));
+
+  beforeEach(() => {
+    fixture = TestBed.createComponent(PopupErrorComponent);
+    component = fixture.componentInstance;
+    fixture.detectChanges();
+  });
+
+  it('should create', () => {
+    expect(component).toBeTruthy();
+  });
+});

src/app/components/popup-error/popup-error.component.ts

@@ -0,0 +1,29 @@
+import { Component } from '@angular/core';
+import { PopUpError } from './../../models/pop-up-error.interface';
+import { ErrorService } from './../../services/error/error.service';
+
+@Component({
+  selector: 'app-popup-error',
+  templateUrl: './popup-error.component.html',
+  styleUrls: ['./popup-error.component.css']
+})
+export class PopupErrorComponent {
+
+  constructor(private errorService: ErrorService) {}
+
+  isErrors(): boolean {
+    return this.errorService.isErrors();
+  }
+
+  getErrors(): PopUpError[] {
+    return this.errorService.getErrors();
+  }
+
+  handleError(error: PopUpError) {
+    this.errorService.handleError(error);
+  }
+
+  clearError(error: PopUpError) {
+    this.errorService.clearError(error);
+  }
+}

src/app/models/pop-up-error.interface.ts

@@ -0,0 +1,6 @@
+export interface PopUpError {
+    errorText: string;
+    errorDescription?: string;
+    handleFunction?: Function;
+    callingScope?: Object;
+}

src/app/services/error/error.service.spec.ts

@@ -0,0 +1,15 @@
+import { TestBed, inject } from '@angular/core/testing';
+
+import { ErrorService } from './error.service';
+
+describe('ErrorService', () => {
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [ErrorService]
+    });
+  });
+
+  it('should be created', inject([ErrorService], (service: ErrorService) => {
+    expect(service).toBeTruthy();
+  }));
+});

src/app/services/error/error.service.ts

@@ -0,0 +1,33 @@
+import { Injectable } from '@angular/core';
+import { PopUpError } from './../../models/pop-up-error.interface';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class ErrorService {
+
+  private errors: PopUpError[] = [];
+
+  addError(error: PopUpError): void {
+    this.errors.push(error);
+  }
+
+  getErrors(): PopUpError[] {
+    return this.errors;
+  }
+
+  clearError(error: PopUpError): void {
+    this.errors.splice(this.errors.indexOf(error), 1);
+  }
+
+  isErrors(): boolean {
+    return !!this.errors.length;
+  }
+
+  handleError(error: PopUpError): void {
+    if (error.handleFunction && typeof error.handleFunction === 'function') {
+      error.handleFunction.call(error.callingScope);
+    }
+    this.clearError(error);
+  }
+}