Category: Uncategorized

Providing a singleton service

Two ways to make a service singleton in Angular

• Declare that the service should be provided in the application root.
• Include the service in the AppModule or in a module that is only imported by the AppModule.

Beginning with Angular 6.0, the preferred way to create a singleton services is to specify on the service that it should be provided in the application root. This is done by setting providedIn to root on the service’s @Injectable decorator:

Prefered Angular 6 Way using @Injectable decorator

• Angular creates a single, shared instance of service and injects into any class that asks for it.
• Registering the provider in the @Injectable metadata also allows Angular to optimize an app by removing the service if it turns out not to be used after all.

import { Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root',
})
export class VoteService {
}

Register Service in providers array of @NgModule

import {VoteService} from './vote.service';
...
@NgModule({
  imports:      [ BrowserModule],
  declarations: [ AppComponent],
  bootstrap:    [ AppComponent],
  providers: [VoteService]
})

Reference

• Understanding provider scope in Angular
• Angular Services do NOT have to be Singletons
• Angular Reference Singleton services

Karma Installation

Install Karma Client on Windows 10 an run it from Command Line

D:\dev\myTestProjects\dobby-the-companion>  npm install -g karma-cli
C:\Users\Helmut\AppData\Roaming\npm\karma -> C:\Users\Helmut\AppData\Roaming\npm\node_modules\karma-cli\bin\karma
+ karma-cli@1.0.1
updated 1 package in 0.421s

D:\dev\myTestProjects\dobby-the-companion>  karma start
08 08 2018 16:03:24.227:WARN [karma]: No captured browser, open http://localhost:9876/
08 08 2018 16:03:24.232:WARN [karma]: Port 9876 in use
08 08 2018 16:03:24.233:INFO [karma]: Karma v1.7.1 server started at http://0.0.0.0:9877/

Run all Karma test

D:\dev\myTestProjects\dobby-the-companion>  ng test
 10% building modules 1/1 modules 0 active(node:25148) DeprecationWarning: Tapable.plugin is deprecated. Use new API on `.hooks` instead
10 08 2018 14:07:37.807:WARN [karma]: No captured browser, open http://localhost:9876/
10 08 2018 14:07:37.813:INFO [karma]: Karma v1.7.1 server started at http://0.0.0.0:9876/
10 08 2018 14:07:37.813:INFO [launcher]: Launching browser Chrome with unlimited concurrency
10 08 2018 14:07:37.817:INFO [launcher]: Starting browser Chrome              10 08 2018 14:07:43.581:WARN [karma]: No captured browser, open http://localhost:9876/

Missing Error Messages with Angular / Karma testing – add source-map=false parameter

D:\dev\myTestProjects\dobby-the-companion>   ng test --source-map=false
 10% building modules 1/1 modules 0 active(node:6332) DeprecationWarning: Tapable.plugin is deprecated. Use new API on `.hooks` instead
10 08 2018 14:24:47.487:WARN [karma]: No captured browser, open http://localhost:9876/
10 08 2018 14:24:47.492:INFO [karma]: Karma v1.7.1 server started at http://0.0.0.0:9876/
10 08 2018 14:24:47.492:INFO [launcher]: Launching browser Chrome with unlimited concurrency
10 08 2018 14:24:47.504:INFO [launcher]: Starting browser Chrome              10 08 2018 14:24:50.370:WARN [karma]: No captured browser, open http://localhost:9876/
10 08 2018 14:24:50.748:INFO [Chrome 67.0.3396 (Windows 10.0.0)]: Connected on socket Ml0r-gsA3JNw1F0sAAAA with id 52984303

• Missing Error Messages with Angular Testing

Run ONLY a single Karma test

Change in your IDE :   
           describe('LoginComponent', () => {
        -> fdescribe('LoginComponent', () => {   

Reference

• What should I use instead of fit and fdescribe in Jasmine 3?

Using RouterTestingModule to test Angular Router Object

Code to be tested

import {Router} from '@angular/router';

export class myComponent  {
  constructor(   private router: Router ) { }           
  triggerMessageAction(m: Message) {
   
    if (m.messageClass === 'internal') {
      this.router.navigate([m.messageLink]);
    } 
  }

Karma/Jasmine Test Code

import {RouterTestingModule} from '@angular/router/testing';
import {Router} from '@angular/router';

describe('WarningDialogComponent', () => {
  
  beforeEach(async(() => {
    TestBed.configureTestingModule({
      ...
      imports: [ RouterTestingModule ],     
    }).compileComponents();
  }));

  beforeEach(inject([MessagesService], (service: MessagesService) => {
   ...
  }));

  it('should close Warning Dialog after pressing on a Warning Action ', inject([MessagesService, Router],
    (service: MessagesService, router: Router) => {
      spyOn(component, 'triggerMessageAction').and.callThrough();
      spyOn(router, 'navigate').and.returnValue(true);
      expect(component.triggerMessageAction).toHaveBeenCalledWith(jasmine.objectContaining( {messageType: 'logout'}));
      expect(router.navigate).toHaveBeenCalledWith('login'); 
    }));
});

Potential Error

Error:  : Expected a spy, but got Function.
Usage: expect().toHaveBeenCalledWith(...arguments)

Fix: Add spyOn for the methode you want to spy
spyOn(router, 'navigate').and.returnValue(true)

Using SpyOn to run UNIT-tests for Angular Router Calls

• spyOn() takes two parameters: the first parameter is the name of the object and the second parameter is the name of the method to be spied upon
• It replaces the spied method with a stub, and does not actually execute the real method
• The spyOn() function can however be called only on existing methods.
• A spy only exists in the describe or it block in which it is defined, and will be removed after each spec

Sample Code

 it(`Fake Login with should set isAuthenticated Flag and finally call route: ects`,
    async(inject([AuthenticationService, HttpTestingController],
    (service: AuthenticationService, backend: HttpTestingController) => {

      spyOn(service.router, 'navigate').and.returnValue(true);

      service.login('Helmut', 'mySecret');
      // Fake a HTTP response with a Bearer Token
      // Ask the HTTP mock to return some fake data using the flush method:
      backend.match({
        method: 'POST'
      })[0].flush({ Bearer: 'A Bearer Token: XXXXXXX' });

      expect(service.router.navigate).toHaveBeenCalled();
      expect(service.router.navigate).toHaveBeenCalledWith(['ects']);
      expect(service.isAuthenticated()).toEqual(true);
    })));

Reference

• Spies: spyOn(), and.callThrough(), and.returnValue(), and.callFake()

My Fist Karma Sample

Screenshot Chrome Browser after running Tests	Details
“;[/insert_php]	Karma verison is v1.7.1 Only 1 of our 18 test was running as we use fdescribe The test shows no error The Screen is devided into 2 divs Div with class html-report shows the test details Div with class root0 shows the angular HTML components

import { async, ComponentFixture, TestBed } from '@angular/core/testing';

import { LoginComponent } from './login.component';
import {FormsModule} from '@angular/forms';
import {RouterTestingModule} from '@angular/router/testing';
import {AuthenticationService} from '../authentication.service';
import {AuthGuard} from '../auth-guard.service';

fdescribe ('LoginComponent', () => {
  let component: LoginComponent;
  let fixture: ComponentFixture<LoginComponent>;
  let h1:        HTMLElement;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ LoginComponent ],
      imports: [FormsModule, RouterTestingModule ],
      providers: [AuthenticationService]
    })
    .compileComponents();
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(LoginComponent);
    component = fixture.componentInstance;
    h1 = fixture.nativeElement.querySelector('h1');
    console.log(h1);

    fixture.detectChanges();
  });

  it('should have <h1> with  TestKarma', () => {
    const loginElement: HTMLElement = fixture.nativeElement;
     h1 = loginElement.querySelector('h1');
    expect(h1.textContent).toEqual('TestKarma');
  });

  it('should be created', () => {
    expect(component).toBeTruthy();
  });
});

Debug Karma Test

• Add debugger keyword to your Java Script Code you want to debug
• Start Karma tests with : ng test
• Add Chrome Debugger Tools by pressing F12
• Reload your page – Javascript code should stop on the line with debugger statement

Screenshot Chrome Browser after running Tests	Details
“;[/insert_php]	“;[/insert_php]

A more complexer Sample setting up a Karma Test Environment for Integration Tests

import { async, ComponentFixture, TestBed } from '@angular/core/testing';

import { CurrentSemesterComponent } from './current-semester.component';
import { CommonHeaderComponent } from '../common-header/common-header.component';
import { NavigationComponent } from '../navigation/navigation.component';
import { RouterTestingModule } from '@angular/router/testing';
import { MatIconModule } from '@angular/material';
import {MatButtonToggleModule} from '@angular/material/button-toggle';
import {AuthenticationService} from '../auth/authentication.service';


fdescribe('CurrentSemesterComponent', () => {
  let component: CurrentSemesterComponent;
  let fixture: ComponentFixture;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ CurrentSemesterComponent,CommonHeaderComponent, NavigationComponent ],
      providers: [AuthenticationService,],
      imports: [RouterTestingModule, MatIconModule, MatButtonToggleModule ],
    })
    .compileComponents();
  }));

  beforeEach(() => {
    fixture = TestBed.createComponent(CurrentSemesterComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });

  it('should create', () => {
    expect(component).toBeTruthy();
  });
});

Jasmine Test Order

• Currently (v2.x) Jasmine runs tests in the order they are defined
• However, there is a new (Oct 2015) option to run specs in a random order, which is still off by default
• According to the project owner, in Jasmine 3.x it will be converted to be the default.

Reference

• Reference

Jasmine and Timeout

Reference

• Testing setTimeout and setInterval with Jasmine

https://makandracards.com/makandra/32477-testing-settimeout-and-setinterval-with-jasmine

Error: router-outlet’ is not a known element:

Error Details

'router-outlet' is not a known element:
1. If 'router-outlet' is an Angular component, then verify that it is part of this module.
2. If 'router-outlet' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message. 

"<app-navigation></app-navigation>
<div class="container">
  [ERROR ->]<router-outlet></router-outlet>
</div>
"): ng:///DynamicTestModule/AppComponent.html@2:2

Fix – import RouterTestingModule

import {RouterTestingModule} from '@angular/router/testing'

describe('AppComponent', () => {
  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [
        AppComponent
      ],
      imports: [ RouterTestingModule ]
    }).compileComponents();
  }));

Reference

• Got a ‘router-outlet’ is not a known element

Error: app-navigation’ is not a known element:

Error Details

AppComponent should create the app
Failed: Template parse errors:
'app-navigation' is not a known element:
1. If 'app-navigation' is an Angular component, then verify that it is part of this module.
2. If 'app-navigation' is a Web Component then add 'CUSTOM_ELEMENTS_SCHEMA' to the '@NgModule.schemas' of this component to suppress this message. ("

<title>app</title>
[ERROR ->]<app-navigation></app-navigation>

Angular code

app.component.html 

<app-navigation></app-navigation>
<div class="container">
  <router-outlet></router-outlet>
</div>


navigation.component.ts 
import {Component, OnInit} from '@angular/core';
import {AuthenticationService} from '../auth/authentication.service';

@Component({
  selector: 'app-navigation',
  templateUrl: './navigation.component.html',
  styleUrls: ['./navigation.component.css']
})
...

Fix – Add a stubbing Object

import { TestBed, async } from '@angular/core/testing';
import { AppComponent } from './app.component';
import {RouterTestingModule} from '@angular/router/testing'
import {Component} from '@angular/core';

@Component({selector: 'app-navigation', template: ''})
class NavigationStubComponent {}

describe('AppComponent', () => {
  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [
        AppComponent,
        NavigationStubComponent
      ],
      imports: [ RouterTestingModule ]
    }).compileComponents();
  })

Reference

• Stubbing unneeded Components

Error Injecting a service

Error Datails: NullInjectorError: No provider for AuthenticationService!

NavigationComponent should create
Error: StaticInjectorError(DynamicTestModule)[NavigationComponent -> AuthenticationService]: 
  StaticInjectorError(Platform: core)[NavigationComponent -> AuthenticationService]: 
    NullInjectorError: No provider for AuthenticationService!

Fix add AuthenticationService to the provider Array

import {AuthenticationService} from '../auth/authentication.service';

describe('NavigationComponent', () => {
  let component: NavigationComponent;
  let fixture: ComponentFixture;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ NavigationComponent ],
      providers: [
        MatSnackBar,
        Overlay,
        AuthenticationService,
        SnackBarComponent,
        DatePipe],
    })
    .compileComponents();
  }));

Error: Failed: Template parse errors

Error Datails: There is no directive with “exportAs” set to “ngForm”

LoginComponent should create
Failed: Template parse errors:
There is no directive with "exportAs" set to "ngForm" ("

<form (ngSubmit)="onLogin(f)" [ERROR ->]#f="ngForm">
  <div class="form-group">
    <label for="username">Benutzer</label>
"): ng:///DynamicTestModule/LoginComponent.html@5:30

Fix: Add FormsModule Import

describe('LoginComponent', () => {
  let component: LoginComponent;
  let fixture: ComponentFixture;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ LoginComponent ],
      imports: [FormsModule ],
      providers: [AuthenticationService]
    })

Reference

• Angular Error – No directive with exportAs set to ngForm

Error: StaticInjectorError(DynamicTestModule)[AuthGuard -> Router]:

Error Datails: NullInjectorError: No provider for Router!

Error: StaticInjectorError(DynamicTestModule)[AuthGuard -> Router]: 
  StaticInjectorError(Platform: core)[AuthGuard -> Router]: 
    NullInjectorError: No provider for Router!
Error: StaticInjectorError(DynamicTestModule)[AuthGuard -> Router]: 
  StaticInjectorError(Platform: core)[AuthGuard -> Router]: 
    NullInjectorError: No provider for Router

Fix: Add RouterTesting Module

import { TestBed, async, inject } from '@angular/core/testing';
import { AuthGuard } from './auth-guard.service';
import {AuthenticationService} from '../auth/authentication.service';

import {RouterTestingModule} from '@angular/router/testing';
describe('AuthGuard', () => {
  beforeEach(() => {
    TestBed.configureTestingModule({
      providers: [AuthGuard,
         AuthenticationService,
      ],
      imports: [
        RouterTestingModule
      ],
    });
  });

Setup for NGXLogger

Note: the setup below should use a single logger instance for both : Code Base and for Karma/Jasmine Tests!

import { TestBed, inject } from '@angular/core/testing';
import {LoggerConfig, LoggerTestingModule, NGXLogger} from 'ngx-logger';

fdescribe('InterceptService', () => {
  beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [
        LoggerTestingModule
      ],
      providers: [   NGXLogger, LoggerConfig, 
       ... ]
    });
  });

fit(' should create and test NGXLogger  !',
    inject([NGXLogger], (logger: NGXLogger) => {
        // config the Logger
      logger.updateConfig({ level: NgxLoggerLevel.DEBUG });
        // send a Test message from our Karma Code to the
      logger.log('Logger Message from Karma Testing Module !');
        // Override the logger instance from our production code
      component.logger = logger;
        // Invoke a function to test  NGXLogger functionality works for our Code Base too !
      component.syncSemsterData();
      expect(component).toBeTruthy();
    }));
});

Logger Output : 
2019-08-13T11:37:46.298Z LOG [semester-goal-setting.component.spec.ts:95] Logger Message from Karma Testing Module !
2019-08-13T11:37:46.743Z LOG [semester-goal-setting.component.ts:130] syncSemsterData():: Subjects: 3 - all Marks Valid : true - saveButtonIsDisabled false

A complexer Sample mocking Services and Components

@Component({selector: 'app-semester-header', template: ''})
class SemesterHeaderStubComponent {}

@Component({selector: 'app-navigation', template: ''})
class NavigationStubComponent {}

export class MockDataService {
  public isReady = true;
  getIsReady(): boolean {
    return this.isReady;
  }
  setAppStatusFailed(): void  {}

  getSemesterById(): Semester {
  return new Semester(1, 20, 30 , false, true,
    [ new Module('Mathematik', 8, 2.2, 2.0, 3.0, true),
               new Module('JAVA Programming 2', 7, 2.2, 2.0, 3.0, true),
    ]);
  }
}

describe('CurrentSemesterComponent', () => {
  let component: CurrentSemesterComponent;
  let fixture: ComponentFixture;
  beforeEach(() => {
    TestBed.configureTestingModule({
      declarations: [ CurrentSemesterComponent, SemesterHeaderStubComponent, NavigationStubComponent],
      imports: [
        LoggerTestingModule,
        RouterTestingModule,
        NoopAnimationsModule
      ],
      schemas:  [NO_ERRORS_SCHEMA],
      providers: [
        NGXLogger,
        LoggerConfig,
        {provide: DataService, useValue: new MockDataService() } ]
    });
    fixture = TestBed.createComponent(CurrentSemesterComponent);
    component = fixture.componentInstance;
    fixture.detectChanges();
  });

  it('should create', () => {
    expect(component).toBeTruthy();
  });

  /*
      Whenever dataService is not ready  setAppStatusFailed() should be called with systemError param
   */
  it('if dataService not READY setAppStatusFailed() should be called with param \'systemError\' ', () => {
    let dataService: MockDataService;
    dataService = TestBed.get(DataService);
    const spy = spyOn(dataService, 'setAppStatusFailed');
    dataService.isReady = false;
    component.ngOnInit();
    expect(component).toBeTruthy();
    expect(dataService.setAppStatusFailed).toHaveBeenCalledWith('systemError');
  });
  /*
        Whenever dataService is READY setAppStatusFailed() should NOT be called anyway
     */
  it('if dataService is READY setAppStatusFailed() should not have been called', () => {
    let dataService: MockDataService;
    dataService = TestBed.get(DataService);
    const spy = spyOn(dataService, 'setAppStatusFailed');
    dataService.isReady = true;
    component.ngOnInit();
    expect(component).toBeTruthy();
    expect(dataService.setAppStatusFailed).not.toHaveBeenCalled();
  });

});

Mock a Service Object

export class MockDataService {
  public isReady = true;

  getSemesterById(semId: number): Semester {
    return new Semester(  '20192' , 30, 0,  '', 0,
      [
        new Mark( 4.5, 5, new Exam ( '6', 'Mathematik S1'), 3, true ),
        new Mark( 2.5, 7, new Exam ( '5', 'JAVA Programming II S1'), 2, true ),
        new Mark( 1.5, 8, new Exam ( '4', 'C ++ Programming II S1'), 2.7, true ),
      ])
  }

}

fdescribe('SemesterGoalSettingComponent', () => {
  let component: SemesterGoalSettingComponent;
  let fixture: ComponentFixture;

  beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ SemesterGoalSettingComponent ],
      schemas: [NO_ERRORS_SCHEMA],
      imports: [ MatTableModule, MatDialogModule, RouterTestingModule, LoggerTestingModule ,  HttpClientModule,
        HttpClientTestingModule, MatSnackBarModule],
      providers: [ NGXLogger, LoggerConfig, MatSnackBar, MatDialog,
        { provide: DataService, useValue: new MockDataService() } ]
    })
    .compileComponents();
  }));
...

Simulate a Button Press Action

Karma/Jasmine Test Code:
beforeEach(() => {
    fixture = TestBed.createComponent(SemesterHeaderComponent);
    component = fixture.componentInstance;
    // 'autoDetectChanges' will continually check for changes until the test is complete.
    // This is slower, but necessary for certain UI changes as changes triggered by ngFor Ops
    fixture.autoDetectChanges(true);
  });

it('Button Press should redirect to Central ECTS Page  ', () => {
    spyOn(component, 'navigateTop');
    const el1 =   fixture.debugElement.query(By.css('#return-to-top-level-page')).nativeElement;
    el1.click();
    expect(component.navigateTop).toHaveBeenCalled();
  });

HTML Code:

    <button id="return-to-top-level-page" class="mat-button-study-progress" mat-button  (click)="navigateTop()" > <mat-icon class="button-navigate-back color_white" >arrow_back_ios</mat-icon> </button>


JavaScript Code:

 navigateTop() {
    this.logger.warn('SemesterHeaderComponent::navigate  to ECTS Page !: ');
    this.router.navigate(['ects']);
  }

About Promise

How Promises Work

A promise is an object which can be returned synchronously from an asynchronous function.
It will be in one of 3 possible states:

• Fulfilled: onFulfilled() will be called (e.g., resolve() was called)
• Rejected: onRejected() will be called (e.g., reject() was called)
• Pending: not yet fulfilled or rejected

Promises following the spec must follow a specific set of rules:

• A promise or “thenable” is an object that supplies a standard-compliant .then() method.
• A pending promise may transition into a fulfilled or rejected state.
• A fulfilled or rejected promise is settled, and must not transition into any other state.
• Once a promise is settled, it must have a value (which may be undefined). That value must not change.
• A Promise can be resolved or rejected, exclusively and only once.
• A call to promise.then returns a promise, so that we can call the next promise
• A value returned by a .then handler is immediately passed to the next handler
• If the returned value is a promise, then the further execution is suspended until it settles.
• A fetch() promise will reject with a TypeError when a network error is encountered or CORS is misconfigured on the server side
• By default, fetch won’t send or receive any cookies from the server

Chained Promises

Chained Promises Sample

function testMe(myUrl, test, dataError) {
    dumpMessage("Testing Promise Chaining: "  + test, false);
    let url = myUrl;
    fetch(url)                           // fetch returns a promise       
        .then(response => {              // Our Success Handler returns response Object 
            if(response.ok) {
                if ( dataError) {        // Just for testing - Mimicking a Data Proessing Error
                    throw new Error('Data Processing Error');
                }  
                return response.json();
            }
            throw new Error('Network response was not ok  at Chain Level 1');
        })  // Catches Exception for our Success Handler and for our Reject Handler 
    .catch(e => { 
        dumpMessage("Exception at Chain Level 1  : " + e,true );  
        throw new Error('Initial Fetch failed for URL: ' + url); 
    })
    .then(jsonData => { dumpMessage("ID: " + jsonData.id + " - name : " + jsonData.name,false ); return(jsonData.name);} )
    .then( (user) => {  dumpMessage("Username: " + user, false);  return fetch("https://api.github.com/users/"+user ); })
        // Load the response as json
    .then(response => response.json())     
        // Show the avatar image (githubUser.avatar_url) for 3 seconds (maybe animate it)
    .then(githubUser => {
        dumpMessage("Displaying Github Avatar Image for 3 seconds!", false);  
        let img = document.createElement('img');
        img.src = githubUser.avatar_url;
        img.className = "promise-avatar-example";
        document.body.append(img);

        setTimeout(() => {
            img.remove();
            dumpMessage("Removed Github Avatar Image !", false);
        }, 3000); // (*)
    })
    .catch(err => {             // Catch all Hanlder return true/false for retry logic 
        dumpMessage("CatchAll Error-handler: " + err, true);
        });
} 

• CodePen Project: Press Working Sample Button

Promises and Error Handling

Overview

Pomisess Error Handling Diagram
“;[/insert_php]

Handle Errors – Pattern 1

save().then(
  handleSuccess,
  handleError
);

• Problem Exceptions in handleSuccess() are not catched

Handle Errors – Pattern 2

save()
  .then(handleSuccess)
  .catch(handleError)


Sample:
 fetch(url)                           // fetch returns a promise       
        .then(response => {              // Our Success Handler returns response Object 
            if(response.ok) {
                if ( dataError) {        // Just for testing - Mimicking a Data Proessing Error
                    throw new Error('Data Processing Error');
                }  
                return response.json();
            }
            throw new Error('Network response was not ok  at Chain Level 1');
        })  // Catches Exception for our Success Handler and for our Reject Handler 
    .catch(e => { 
        dumpMessage("Exception at Chain Level 1  : " + e,true );  
        throw new Error('Initial Fetch failed for URL: ' + url); 
    })
    .then(jsonData => { dumpMessage("ID: " + jsonData.id + " - name : " + jsonData.name,false ); return(jsonData.name);} )
    ...

• Handles both Processing Errors and Network Errors
• CodePen Project: Press Invalid URL & Data Error Button

Handle Errors – Pattern 3

save()
  .then(
    handleSuccess,
    handleNetworkError    -> Handle and Fix Network Error
  )
  .catch(handleProgrammerError) -> Handle anf Fix ProgamError in handleSucessFunction


Sample:
    fetch(url)                      
        .then(response => {              // Our Success Handler 
            if(response.ok) {
                if ( dataError) {        // Mimicking a Data Proessing Error
                    throw new Error('Data Processing Error');
                }  
                return response.json();
            }
            throw new Error('Network response was not ok.');
        },      
        err => {    // Now we handle the error (rejection reason)
            dumpMessage("Handle error (rejection reason): " + err,true );  
               // Create a Dummy object
            dumpMessage("Create a Default Object to Finish Promise Chain");    
            myObj = { "name":"hhutzler", "id":999 };
            return myObj;
        } )
        .catch(e => { dumpMessage("Processing Error Chaining at Level 1  : " + e,true );  
            dumpMessage("Create a Default Object to Finish Promise Chain");    
            myObj = { "name":"hhutzler", "id":999 };
            return myObj;                   
        })
            //        ,        // Now we handle the error (rejection reason)
            //e => { dumpMessage("Initial Fetch Error: " + e,true );  throw new Error('Initial Fetch Error for URL' + url); } )
            //.then(response =>  response.json() )
    .then(jsonData => { dumpMessage("ID: " + jsonData.id + " - name : " + jsonData.name,false ); return(jsonData.name);} )
    ....

• Allows us to handle Network errors and Program Errors individually
• CodePen Project: Press FIX Invalid URL & FIX Data Error Button

Reference

• CodePen Project
• Promises chaining Tutorial
• What is a promise ?
• Introduction to Fetch

Setup

• Html Page was loaded from: localhost
• PHP file was loaded from: http://hhutzler.de

JavaScript Code

console.log("Testing Promise Chaining by Returning New Promises");
fetch("http://hhutzler.de/myID.php")
  .then(response =>  response.json() )
  .then(jsonData => { console.log("ID returned by node-fetch Module : " + jsonData.id + " - name : " + jsonData.name );} );

PHP Code

$myObj = new stdClass();
$myObj->id=999;
$myObj->name = "hhutzler";
$myObj->city = "Sattelmanmsburg";

$myJSON = json_encode($myObj);

echo $myJSON;

Expected CORS Error

 
Failed to load http://hhutzler.de/myID_NW.php: No 'Access-Control-Allow-Origin' header is present on the requested resource. 
Origin 'http://localhost' is therefore not allowed access. 
If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

FIX – Add Access-Control-Allow-Origin to the PHP File

 
header('Access-Control-Allow-Origin: *'); 

$myObj = new stdClass();
$myObj->id=999;
$myObj->name = "hhutzler";
$myObj->city = "Sattelmanmsburg";

$myJSON = json_encode($myObj);

echo $myJSON;

Overview JIRA

What is a Board ?

A board displays issues from one or more projects, giving you a flexible way of viewing, managing, and reporting on work in progress. There are two types of boards in Jira Software:

• Scrum board: For teams that plan their work in sprints. Includes a backlog.
• Kanban board: For teams that focus on managing and constraining their work-in-progress. Includes the option of a Kanban backlog.

What is a Epic ?

An epic captures a large body of work. It is essentially a large user story that can be broken down into a number of smaller stories. It may take several sprints to complete an epic.

What is a Sprint ?

A sprint — also known as an iteration — is a short (ideally two to four week) period in which the development team implements and delivers a discrete product increment, e.g. a working milestone version.

Introduction to JIRA & Agile Project Management

Install JIRA

Downlaod JIRA

• JIRA Download Location

Install JIRA on Windows 7

D:\Program Files\Atlassian\JIRA\bin> dir \software
20.01.2018  15:16       350.857.328  atlassian-jira-software-7.7.0-x64.exe

As Administrator run: atlassian-jira-software-7.7.0-x64.exe
Select: 
  Advanced Mode for installation 
  Ports 9080 9005     [ change Ports if needed ]
  Start as a service  [ Start JIRA as a service ]
Login: 
  Email: 	   Helmut.Hutzler@gmail.com
  Benutzer:  Helmut.Hutzler
  Password:  .....it
Config: 
  Running the Setup Wizard 

Reference JIRA Installation

• How to Install JIRA on Windows
• Running the Setup Wizard

Run JIRA on our local System JIRA

• Note the Link below: http://localhost:9080/secure/Dashboard.jspa works ONLY on my local System !
• Run JIRA Dashbaord

Working with JIRA

Create a Board using multiple Projects

Create an Agile Board from Existing Projects
“;[/insert_php]
Add multiple projects to the Board
“;[/insert_php]

Add a new Project to an existing Board

Boards -> View All Boards -> Configure -> Edit Filter Query -> Press Left Menu Button -> Add/Delete Projects
“;[/insert_php]

Reconfigure JIRA by running Setup Wizard again

Stop JIRA 
D:\Program Files\Atlassian\JIRA\bin> stop-jira.bat

Delete dbconfig.xml 
D:\Program Files\Atlassian\Application Data\JIRA> del dbconfig.xml

Delete Database Files 
D:\Program Files\Atlassian\Application Data\JIRA\database> dir
21.01.2018  10:16         2.838.528 h2db.mv.db
21.01.2018  09:18            16.208 h2db.trace.db
               2 Datei(en),      2.854.736 Bytes
               2 Verzeichnis(se), 82.347.048.960 Bytes frei

D:\Program Files\Atlassian\Application Data\JIRA\database> del *.db
Möchten Sie "D:\Program Files\Atlassian\Application Data\JIRA\database\*" löschen (J/N)? j

Open JIRA Baseurl to restart the configuration process: http://localhost:9080/

Reference

• Reconfigure JIRA by running Setup Wizard again

Reference

• Reconfigure JIRA by running the setup wizard again
• Creating a Sprint
• Introduction to JIRA & Agile Project Management
• GOTO 2015 • Agile is Dead • Pragmatic Dave Thomas

Install Mocha, Chai, Selenium and Chromdriver

Init local Repository

D:\xampp\htdocs\pvdata\testSelenium\test> npm init
..
package name: (test) testselenium
version: (1.0.0)
description: test Selenium and Mocha
entry point: (googlePage.js) test_s5.js
test command:
git repository:
keywords:
author: Helmut
license: (ISC)
About to write to D:\xampp\htdocs\pvdata\testSelenium\test\package.json:

{
  "name": "testselenium",
  "version": "1.0.0",
  "description": "test Selenium and Mocha",
  "main": "test_s5.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "Helmut",
  "license": "ISC"
}

Is this ok? (yes)
..

Install local Nodejs Modules

D:\xampp\htdocs\pvdata\testSelenium\test > npm install chromedriver@2.34.1 --save

> chromedriver@2.34.1 install D:\xampp\htdocs\pvdata\testSelenium\test\node_modules\chromedriver
> node install.js

Downloading https://chromedriver.storage.googleapis.com/2.34/chromedriver_win32.zip
Saving to D:\Users\helmut\AppData\Local\Temp\chromedriver\chromedriver_win32.zip
Received 781K...
Received 1568K...
Received 2352K...
Received 3136K...
Received 3222K total.
Extracting zip contents
Copying to target path D:\xampp\htdocs\pvdata\testSelenium\test\node_modules\chromedriver\lib\chromedriver
Done. ChromeDriver binary available at D:\xampp\htdocs\pvdata\testSelenium\test\node_modules\chromedriver\lib\chromedriver\chromedriver.exe
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN testselenium@1.0.0 No repository field.

+ chromedriver@2.34.1
added 96 packages in 14.552s

D:\xampp\htdocs\pvdata\testSelenium\test> npm install selenium-webdriver@3.6.0 --save
npm WARN testselenium@1.0.0 No repository field.

+ selenium-webdriver@3.6.0
added 14 packages in 4.256s

D:\xampp\htdocs\pvdata\testSelenium\test> npm install chai --save
npm WARN testselenium@1.0.0 No repository field.

+ chai@4.1.2
added 7 packages in 2.129s

Verify Local Module Status

D:\xampp\htdocs\pvdata\testSelenium\test> npm  list --depth=0
testselenium@1.0.0 D:\xampp\htdocs\pvdata\testSelenium\test
+-- chai@4.1.2
+-- chromedriver@2.34.1
`-- selenium-webdriver@3.6.0

Install Mocha as a Global Nodejs Module

D:\xampp\htdocs\pvdata\testSelenium\test> npm -g install mocha@4.1
D:\Users\helmut\AppData\Roaming\npm\mocha -> D:\Users\helmut\AppData\Roaming\npm\node_modules\mocha\bin\mocha
D:\Users\helmut\AppData\Roaming\npm\_mocha -> D:\Users\helmut\AppData\Roaming\npm\node_modules\mocha\bin\_mocha
+ mocha@4.1.0
updated 1 package in 4.61s

Verify Global Package Status

D:\xampp\htdocs\pvdata\testSelenium\test> npm  list --depth=0  -g
D:\Users\helmut\AppData\Roaming\npm
+-- eslint@4.16.0
`-- mocha@4.1.0

Testscripts

Script: test_s4.js

require('chromedriver');
var assert = require('chai').assert;
var selenium = require('selenium-webdriver');
var test = require('selenium-webdriver/testing');
var driver;
var GooglePage = require('./googlePage.js');

const timeOut = 15000;
 
test.describe('Testing Google Search Page', function() {
  test.beforeEach(function() {
  	dumpMessage("-> beforeEach Hook");
    this.timeout(timeOut);
    driver = new selenium.Builder()
    	.forBrowser('chrome')
    	.build();
  	var googlePage = new GooglePage(driver);
    googlePage.view();

  });
  
  test.it( 'Working TestCase' , function(){  
    this.timeout(timeOut);
  	driver.getTitle().then(function(title){
  		dumpMessage("Found Page Title: " + title);
  		assert.equal("Google",title );
	});
	dumpMessage("--> Start Processing" ); 
	driver.findElement(selenium.By.name('q')).sendKeys('webdriver');           // Fill in the  Search String for Google Search 
	driver.findElement(selenium.By.name('btnK')).click();					   // Start the Google Search 	
    dumpMessage("--> Leaving Processing" ); 
  });
  
    test.it( 'Failing TestCase' , function(){  
    this.timeout(timeOut);
  	driver.getTitle().then(function(title){
  		dumpMessage("Found Page Title: " + title);
  		assert.equal("xGoogle",title );
	});
	dumpMessage("--> Start Processing" ); 
	driver.findElement(selenium.By.name('q')).sendKeys('webdriver');           // Fill in the  Serach String to the 
	driver.findElement(selenium.By.name('btnK')).click();					   	// Start the Google Search 	
    dumpMessage("--> Leaving Processing" ); 
  });
            
  test.afterEach(function() {
  	  var promise;
  	  var waitTime = 2000;       // Keep the browser window 2 seconds open before calling driver.quit()
  	  this.timeout(10000);       // Increase Timeout ot avoid Error: Timeout of 2000ms exceeded. 
								 // If returning a Promise, ensure it resolves.        
    	promise = new Promise(function(resolve, reject){
        	setTimeout(function(){
           		dumpMessage("-> afterEach Hook Promise called - WaitTime: " +  waitTime );
           		driver.quit();
            	resolve();
        	}, waitTime);
 		});
    	// mocha will wait for the promise to be resolved before exiting
    	return promise;      		
  	dumpMessage("-> afterEach Hook");
  });

});
															 		// Helper Functions 							
function dumpMessage(mesg) {                                        // console.log at top level will create a undefined message
	console.log(getTime() + mesg);                                  // Provide a wrapper function which returns some data 
	return "---------------------------------------------------";	
}

function getTime() {
	var ts = new Date();
    return ts.toLocaleTimeString()+ ":" + ts.getMilliseconds() + "  ";
}

Script: googlePage.js

var webdriver = require('selenium-webdriver');
 
GooglePage = function GooglePage(driver) {
  this.driver = driver;
  this.url = "http://www.google.com/ncr";
};
 
GooglePage.prototype.view = function() {
  this.driver.get(this.url);
  return webdriver.promise.fulfilled(true);
};
 
module.exports = GooglePage;                     // export the module so in an be imported with the require syntax

Running the Mocha/Selenium Testcase

Testcase Overview

• Testcase consists out of 2 tests !
• Both tests starts and closes the Chromedriver
• Testcase 1 should work !
• Testcase 2 should fail !

Testcase Details

Command: mocha test_s5.js
“;[/insert_php]

A more complete Testcase

• Selenium WebDriver/Mocha test Script
• Test Script for Initial Page Load
• HTML Page

NetBeans Output

Press F6 in Netbeans to Start Test Scripts
“;[/insert_php]

Reference

• JavaScript with Selenium WebDriver and Mocha

Versions used

• Netbeans IDE 8.2
• Mocha 4.0.1 – Our Testing Tool
• Chai 4.1.2 – An Assert Library

Create a HTML5 Project with Javascript Support inside Netbeans

Create a HTML5/Javascript Project and add Javascript File main2.js to the project
“;[/insert_php]

• Note: exports is a node.js concept that declares the functions that your module makes available to code outside itself

Setup Mocha as Testing Provider

Change Project Properties for Javascript Testing
“;[/insert_php]

Setup Mocha/Chai [ Open a Netbeans Terminal Window]

Initialize new Node.js Project

$ cd D:\xampp\htdocs\pv\mochaTest2
$ npm init                                                                                                                                                                                  
This utility will walk you through creating a package.json file.
It only covers the most common items, and tries to guess sensible defaults.

See `npm help json` for definitive documentation on these fields
and exactly what they do.

Use `npm install ` afterwards to install a package and
save it as a dependency in the package.json file.

Press ^C at any time to quit.
package name: (mochatest2) 
version: (1.0.0) 
description: Mocha/Chai Testing
entry point: (index.js) main2.js
test command: mocha
git repository: 
keywords: 
author: Helmut
license: (ISC) MIT
About to write to D:\xampp\htdocs\pv\mochaTest2\package.json:

{
  "name": "mochatest2",
  "version": "1.0.0",
  "description": "Mocha/Chai Testing",
  "main": "main2.js",
  "directories": {
    "test": "test"
  },
  "scripts": {
    "test": "mocha"
  },
  "author": "Helmut",
  "license": "MIT"
}


Is this ok? (yes) yes

helmut@myPC /cygdrive/d/xampp/htdocs/pv/mochaTest2

Setup Mocha and Chai in our Netbeans Project Base Directory

helmut@myPC /cygdrive/d/xampp/htdocs/pv/mochaTest2
$  npm install mocha                                                                                                                                                                       
npm WARN mochatest2@1.0.0 No repository field.
+ mocha@4.0.1
added 24 packages in 2.189s

helmut@myPC /cygdrive/d/xampp/htdocs/pv/mochaTest2
$  npm install chai                                                                                                                                                                          
npm WARN mochatest2@1.0.0 No repository field.

+ chai@4.1.2
added 7 packages in 1.304s

Verify package.json – created by our previous setup steps

helmut@myPC /cygdrive/d/xampp/htdocs/pv/mochaTest2
$ cat   package.json 
{
  "name": "mochatest2",
  "version": "1.0.0",
  "description": "Mocha/Chai Testing",
  "main": "main2.js",
  "directories": {
    "test": "test"
  },
  "scripts": {
    "test": "mocha"
  },
  "author": "Helmut",
  "license": "MIT",
  "dependencies": {
    "chai": "^4.1.2",
    "mocha": "^4.0.1"
  }
}

Create and Run Mocha testscript manually under Unit Test direcorty

Manually run Mocha Tests via Netbeans Terminal Window
“;[/insert_php]

• Our test script mochaTest2.js imports the functions from Chai and main2.js via require()
• describe()` is merely used for grouping test Tests – can be nested if needed
• `it()` is a test case

Finally run Neteans Unit Tests [ ALT F6]

Open Netbeans Test Result Window to review Test Results
“;[/insert_php]

• Note: If Netbeans IDE hangs during Testing you may need to restart Netbeans to fix this !

Reference

How To Unit Testing JavaScript with Netbeans
Mocha Homepage
Working with package.json
An Absolute Beginner’s Guide to Using npm
Understanding module.exports and exports in Node.js