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Part-3 |Blazor WebAssembly[.NET 7] JWT Authentication Series | Implement Blazor AuthenticationStateProvider & Invoke Secure Endpoint Using JWT Access Token

The main objectives of this article are:
  • Implement Blazor WebAssembly AuthenticationStateProvider
  • Invoke Secure Endpoint Using JWT Access Token

AuthenticationStateProvider:

In Blazor WebAssembly user authentication information can be accessed using the 'AuthenticationStateProvider'.

Install 'Microsoft.AspNetCore.Components.Authorization' Package In Blazor Application:

Let's install the 'Microsoft.AspNetCore.Components.Authorization' package in to our 'Blazor WebAssembly' application.

Install 'Blazored.LocalStorage' Package In Blazor Application:

To interact with browser's localstorage we have to install the 'Blazored.LocalStorage' package in the Blazor WebAssembly application.

Now register the service in 'Program.cs'
Program.cs:
builder.Services.AddBlazoredLocalStorage();

Implement AuthenticationStateProvider In Blazor WebAssembly Application:

To create user authentication context we have to implement the 'AuthenticationStateProvider'. So let's create a class like 'CustomAuthProvider.cs' in 'Shared/Providers' folders.
Blazor_App/Shared/Providers/CustomAuthProvider.cs:
 
using Blazored.LocalStorage;
using Microsoft.AspNetCore.Components.Authorization;
using System.Security.Claims;
using System.Text.Json;

namespace JWT.Auth.BlazorUI.Shared.Providers
{
    public class CustomAuthProvider : AuthenticationStateProvider
    {
        private readonly ILocalStorageService _localStorageService;
        public CustomAuthProvider(ILocalStorageService localStorageService)
        {
            _localStorageService = localStorageService;
        }
        public override async Task<AuthenticationState> GetAuthenticationStateAsync()
        {
            var jwtToken = await _localStorageService.GetItemAsync<string>("jwt-access-token");
            if (string.IsNullOrEmpty(jwtToken))
            {
                return new AuthenticationState(
                    new ClaimsPrincipal(new ClaimsIdentity()));
            }
            return new AuthenticationState(
                    new ClaimsPrincipal(new ClaimsIdentity(ParseClaimsFromJwt(jwtToken), "jwtAuth")));
        }

        private static IEnumerable<Claim> ParseClaimsFromJwt(string jwt)
        {
            var claims = new List<Claim>();
            var payload = jwt.Split('.')[1];

            var jsonBytes = ParseBase64WithoutPadding(payload);

            var keyValuePairs = JsonSerializer.Deserialize<Dictionary<string, object>>(jsonBytes);
            claims.AddRange(keyValuePairs.Select(kvp => new Claim(kvp.Key, kvp.Value.ToString())));
            return claims;
        }
        private static byte[] ParseBase64WithoutPadding(string base64)
        {
            switch (base64.Length % 4)
            {
                case 2: base64 += "=="; break;
                case 3: base64 += "="; break;
            }
            return Convert.FromBase64String(base64);
        }

        public void NotifyAuthState()
        {
            NotifyAuthenticationStateChanged(GetAuthenticationStateAsync());
        }
    }
}
  • (Line: 9) Inherit the 'Microsoft.AspNetCore.Components.Authorization.AuthenticationStateProvider'.
  • (Line: 11-15) Injected the 'Blazored.Localstorage.ILocalStorageService'.
  • (Line: 15) Here we implement the 'GetAuthenticationStateAsync()'.
  • (Line: 18) Trying to read the jwt access token from the browser local storage.
  • (Line: 19-23) If there is no jwt token then we create 'AuthenticationState' instance with empty 'ClaimsPrincipal' that makes user is not authenticated.
  • (Line: 24-25) If token exist we will read cliams from it and then prepares the 'ClaimsPrincipal' instance and then will pass to the 'AuthenticationState'.
  • (Line: 28-47) Decoding our JWT access token to read user claims from it.
  • (Line: 51) The 'NotifyAuthenticationStateChanged' is used to refresh the 'AuthenticationState' provider.
Now register our 'CustomAuthProvider' in 'Program.cs'
Blazor_Project/Program.cs:
builder.Services.AddAuthorizationCore();
builder.Services.AddScoped<AuthenticationStateProvider, CustomAuthProvider>();
Render the 'CascadingAuthenticationState' component in 'App.razor'.
Blazor_Project/App.razor:
<CascadingAuthenticationState>
    <Router AppAssembly="@typeof(App).Assembly">
        <Found Context="routeData">
            <RouteView RouteData="@routeData" DefaultLayout="@typeof(MainLayout)" />
            <FocusOnNavigate RouteData="@routeData" Selector="h1" />
        </Found>
        <NotFound>
            <PageTitle>Not found</PageTitle>
            <LayoutView Layout="@typeof(MainLayout)">
                <p role="alert">Sorry, there's nothing at this address.</p>
            </LayoutView>
        </NotFound>
    </Router>
</CascadingAuthenticationState>
Now conditionally display 'Login' & 'Registration' links in the 'MainLayout.razor'.
Blazor_Project/Shared/MainLayout.razor:(HTML Part)
<MudAppBar Color="Color.Primary" >
	<MudLink Underline="Underline.None" Color="Color.Inherit" Href="/">JWT Auth Demo</MudLink>
	<MudSpacer />
	<AuthorizeView>
		<Authorized>
			<span>@(UserDisplayName(context.User.Claims.ToList()))</span>
		</Authorized>
		<NotAuthorized>
			<MudLink Underline="Underline.None" Color="Color.Inherit" Href="/login" Class="mr-2">Login</MudLink>
			<MudLink Underline="Underline.None" Color="Color.Inherit" Href="/registration">Registration</MudLink>
		</NotAuthorized>
	</AuthorizeView>
	
</MudAppBar>
  • Here 'AuthorizeView' component helps to render the content based on user authentication. The 'Authorized' component renders if user authenticated. In Authorized component we can access user information throught 'context.User'. The 'NotAuthorized' component renders the content if user not authenticated.
Blazor_Project/Shared/MainLayout.razor:(C# Part) 
@code {
    private string UserDisplayName(List<Claim> claims)
    {
        var firstName = claims.Where(_ => _.Type == "FirstName").Select(_ => _.Value).FirstOrDefault();
        var lastName = claims.Where(_ => _.Type == "LastName").Select(_ => _.Value).FirstOrDefault();

        if(!string.IsNullOrEmpty(firstName) || !string.IsNullOrEmpty(lastName))
        {
            return $"{firstName} {lastName}";
        }
        var email = claims.Where(_ => _.Type == "Email").Select(_ => _.Value).FirstOrDefault();
        return email;
    }
}
  • Here we preparing authenticated user name to display on the menu.
Now let's create API response model like 'JWTTokenResponseVm' in 'ViewModels/Accounts' folder.
Blazor_Project/ViewModels/Account/JWTTokenResponseVm.cs:
namespace JWT.Auth.BlazorUI.ViewModels.Account
{
    public class JWTTokenResponseVM
    {
        public string AccessToken { get; set; }
    }
}
Now store the JWT access token to browser local storage.
Blazor_Project/Pages/Account/Login.razor:(HTML Part)
  The lang-* class specifies the language file extensions.
@page "/login"
@using System.Text.Json;
@using System.Text;
@using Blazored.LocalStorage;
@using JWT.Auth.BlazorUI.Shared.Providers;
@inject HttpClient _http
@inject ILocalStorageService _localStorageService
@inject AuthenticationStateProvider _authStateProvider;
<div class="ma-6 d-flex justify-center">
    <MudChip Color="Color.Primary">
        <h3>Login Form</h3>
    </MudChip>

</div>
<div class="ma-6 d-flex  justify-center">
    <MudCard Width="500px">
        <MudForm Model="loginModel" @ref="form" Validation="loginValidation.ValidateValue">
            <MudCardContent>
                @if (!string.IsNullOrEmpty(APIErrorMessage))
                {
                    <MudChip Class="d-flex justify-center" Color="Color.Error">
                        <h3>@APIErrorMessage</h3>
                    </MudChip>
                }
                <MudTextField @bind-Value="loginModel.Email"
                              For="@(() => loginModel.Email)"
                              Immediate="true"
                              Label="Email" />
                <MudTextField @bind-Value="loginModel.Password"
                              For="@(() => loginModel.Password)"
                              Immediate="true"
                              Label="Password" InputType="InputType.Password" />
                <MudCardActions>
                    <MudButton Variant="Variant.Filled" Color="Color.Primary" Class="ml-auto" OnClick="LoginAsync">Login</MudButton>
                </MudCardActions>
            </MudCardContent>
        </MudForm>
    </MudCard>
</div>
  • (Line: 8) Injected the 'ILocalStorageService'.
  • (Line: 9) Injected the 'AuthenticationStateProvider'.
Blazor_Project/Pages/Account/Login.razor:(C# Part) 
@code {
    LoginVm loginModel = new LoginVm();

    LoginValidationVm loginValidation = new LoginValidationVm();

    MudForm form;

    string APIErrorMessage = string.Empty;

    private async Task LoginAsync()
    {
        await form.Validate();
        if (form.IsValid)
        {
            var jsonPayload = JsonSerializer.Serialize(loginModel);
            var requestContent = new StringContent(jsonPayload, Encoding.UTF8, "application/json");


            var response = await _http.PostAsync("/api/User/login", requestContent);

            if (response.StatusCode == System.Net.HttpStatusCode.BadRequest)
            {
                var errors = await response.Content
                .ReadFromJsonAsync<Dictionary<string, List<string>>>();
                if (errors.Count > 0)
                {
                    foreach (var item in errors)
                    {
                        foreach (var errorMessage in item.Value)
                        {
                            APIErrorMessage = $"{errorMessage} | ";
                        }
                    }
                }
            }
            else if (response.StatusCode == System.Net.HttpStatusCode.OK)
            {
                var tokenResponse = await response.Content.ReadFromJsonAsync<JWTTokenResponseVM>();
                await _localStorageService.SetItemAsync<string>("jwt-access-token", tokenResponse.AccessToken);
                (_authStateProvider as CustomAuthProvider).NotifyAuthState();
            }
            else
            {
                APIErrorMessage = "Unable to do login, please try later";
            }
        }
    }
}
  • (Line: 39) Storing our Jwt access token to the browser local storage.
  • (Line: 40) Refreshing the AuthenticationStateProvider by calling the 'NotifyAuthState' method from the 'CustomAuthProvider'.

Configure JWT Authentication Service In API Project:

Install the 'Microsoft.AspNetCore.Authentication.JwtBearer' package in the API project.

Now register the Jwt authentication service in 'Program.cs'.
API_Project/Program.cs:
builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
.AddJwtBearer(options =>
{
	var tokenSettings = builder.Configuration.GetSection("TokenSettings").Get<TokenSettings>();
	options.TokenValidationParameters = new TokenValidationParameters
	{
		ValidateIssuer = true,
		ValidIssuer = tokenSettings.Issuer,

		ValidateAudience = true,
		ValidAudience = tokenSettings.Audience,

		ValidateIssuerSigningKey = true,
		IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(tokenSettings.SecretKey)),

		ClockSkew = TimeSpan.Zero
	};
});
  • (Line: 1) Defined the authentication type by assigning the name of the authentication type like 'JwtBearerDefaults.AuthenticationScheme'.
  • (Line: 1-18) Defined the JwtBearer service with the required configuration to validate the JWT token.
  • (Line: 4) Loading the token settings from the JSON file.
  • (Line: 5) Initialized the 'TokenValidationParameter' instance.
  • (Line: 7&8) The 'ValidIssuer' assign the value from the token settings and enable issuer validation by setting 'true' for 'ValidateIssuer'. So these configurations check the issue value inside of token matches.
  • (Line: 10&11) validate the audience value in the token
  • (Line: 13&14) validate the sing in signature key value.
  • (Line: 16) The 'ClockSkew' set to '0' seconds considers token expiration exactly, the default value of 'ClockSkew' is '300s' seconds which means the toke will live for extra 5 minutes of original expiration time.
Let's secure our 'WeatherForecast' endpoint by adding the 'Authorization' endpoint.
API_Project/Controllers/WeatherForecastController.cs:

Use HTTPClientFactory In Blazor WebAssembly Application:

Note: Currently We using default HTTPClient instance directly in our Blazor Pages. Next step we will create HTTP Delegate Handler for bi-passing the request. So to configure the HTTP Delegate Hander easily it is easy with HTTPClientFactory. So let's remove the 'HTTPClient' instance injection and replace with 'IHttpClientFactory' instance in all Blazor pages.

In Blazor Application let's install the package like the 'Microsoft.Extensions.Http' package.

Now register the 'Named Type' HttpClient instance in the 'Program.cs'
BlazorWasm_Project/Program.cs:
//builder.Services.AddScoped(sp => new HttpClient { BaseAddress = new Uri("https://localhost:7045/"), });

builder.Services.AddHttpClient("API", options => {
    options.BaseAddress = new Uri("https://localhost:7045/");
})
  • Here 'API' name to register the HTTPClient instance with some configuration like domain. Same name will be used to create the HTTPClient instance from the HTTPClientFactory.
Let's update the 'Login.razor' to use the IHttpClientFactory.
BlazorWasm_Project/Pages/Accounts/Login.razor:
@page "/login"
@using System.Text.Json;
@using System.Text;
@using Blazored.LocalStorage;
@using JWT.Auth.BlazorUI.Shared.Providers;
@inject IHttpClientFactory _httpClientFactory
@inject ILocalStorageService _localStorageService
@inject AuthenticationStateProvider _authStateProvider;
@inject NavigationManager _navigationManager

<! -- HTML content hidden for display purpose -->

@code {
    LoginVm loginModel = new LoginVm();

    LoginValidationVm loginValidation = new LoginValidationVm();

    MudForm form;

    string APIErrorMessage = string.Empty;

    private async Task LoginAsync()
    {
        await form.Validate();
        if (form.IsValid)
        {
            var jsonPayload = JsonSerializer.Serialize(loginModel);
            var requestContent = new StringContent(jsonPayload, Encoding.UTF8, "application/json");

            var httpClient = _httpClientFactory.CreateClient("API");

            var response = await httpClient.PostAsync("/api/User/login", requestContent);

            if (response.StatusCode == System.Net.HttpStatusCode.BadRequest)
            {
                var errors = await response.Content
                .ReadFromJsonAsync<Dictionary<string, List<string>>>();
                if (errors.Count > 0)
                {
                    foreach (var item in errors)
                    {
                        foreach (var errorMessage in item.Value)
                        {
                            APIErrorMessage = $"{errorMessage} | ";
                        }
                    }
                }
            }
            else if (response.StatusCode == System.Net.HttpStatusCode.OK)
            {
                var tokenResponse = await response.Content.ReadFromJsonAsync<JWTTokenResponseVM>();
                await _localStorageService.SetItemAsync<string>("jwt-access-token", tokenResponse.AccessToken);
                (_authStateProvider as CustomAuthProvider).NotifyAuthState();
                _navigationManager.NavigateTo("/fetchdata");
            }
            else
            {
                APIErrorMessage = "Unable to do login, please try later";
            }
        }
    }
}
  • (Line: 6) Injected the 'IHttpClientFactory' 
  • (Line: 9) Injected the 'NavigationManager'
  • (Line: 30) Creating the 'HttpClient' instance from the 'IHttpClientFactory' by using the registered name.
  • (Line: 54) On successful login navigate to 'fetchdata' page.
Let's update the 'Registration.razor' to use IHttpClientFactory.
BlazorWasm_Project/Pages/Accounts/Registration.razor:
@page "/registration"
@using System.Text.Json;
@using System.Text;
@inject IHttpClientFactory _httpClientFactory
@inject NavigationManager _navigationManager

<!-- Html content hidden for display purpose -->

@code {
    RegistrationVM registrationModel = new RegistrationVM();

    RegistrationValidationVm registrationValidator; 

    MudForm form;

    string APIErrorMessage = string.Empty;

    

    protected override Task OnInitializedAsync()
    {
        var httpClient = _httpClientFactory.CreateClient("API");
        registrationValidator = new RegistrationValidationVm(httpClient);
        return base.OnInitializedAsync();
    }


    private async Task RegisterAsync()
    {
        await form.Validate();
        if (form.IsValid)
        {
            // invoke register API call.
            var jsonPayload = JsonSerializer.Serialize(registrationModel);
            var requestContent = new StringContent(jsonPayload, Encoding.UTF8, "application/json");

            var httpClient = _httpClientFactory.CreateClient("API");
            var response = await httpClient.PostAsync("/api/user/register", requestContent);
            if(response.StatusCode == System.Net.HttpStatusCode.BadRequest)
            {
                var errors = await response.Content
                .ReadFromJsonAsync<Dictionary<string, List<string>>>();
                if(errors.Count > 0)
                {
                    foreach (var item in errors)
                    {
                        foreach (var errorMessage in item.Value)
                        {
                            APIErrorMessage = $"{errorMessage} | ";
                        }
                    }
                }
            }
            else if(response.StatusCode == System.Net.HttpStatusCode.OK)
            {
                _navigationManager.NavigateTo("/registration-confirmation");
            }
            else
            {
                APIErrorMessage = "Failed To Register User Please Try After SomeTime";
            }
        }
    }
}
  • (Line: 4) Injected the 'IHttpClientFactory'.
  • (Line: 22&37) Creating the HttpClient instance from the IHttpClientFactory.
The 'FetchData.razor' component we want to display it for the logged-in user. So in this component also let's use the IHttpClientFactory.
BlazorWasm_Project/Pages/FetchData.razor:
@page "/fetchdata"

@inject IHttpClientFactory _httpClientFactory

<!-- Html content hidden for display purpose -->

@code {
    private WeatherForecast[]? forecasts;

    protected override async Task OnInitializedAsync()
    {

        var httpClient = _httpClientFactory.CreateClient("API");
        forecasts = await httpClient.GetFromJsonAsync<WeatherForecast[]>("/WeatherForecast");
    }

    public class WeatherForecast
    {
        public DateOnly Date { get; set; }

        public int TemperatureC { get; set; }

        public string? Summary { get; set; }

        public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
    }
}
  • (Line: 3) Injected the 'IHttpClientFactory'.
  • (Line: 13) Creating the HttpClient instance from the 'IHttpClientFactory'.
  • (Line: 14) Configured the 'WeatherForeCast' endpoint.
Let's add the 'Weather Forecast' as a menu to display for authenticated users.
BlazorWasm_Project/Shared/MainLayout.razor:
<MudAppBar Color="Color.Primary" >
	<MudLink Underline="Underline.None" Color="Color.Inherit" Href="/">JWT Auth Demo</MudLink>
	<AuthorizeView>
		<Authorized>
			<MudLink Underline="Underline.None" Color="Color.Inherit" Href="/fetchdata" Class="ml-2">Weather Forecast</MudLink>
		</Authorized>
	</AuthorizeView>
	<MudSpacer />
	<AuthorizeView>
		<Authorized>
			<span>@(UserDisplayName(context.User.Claims.ToList()))</span>
		</Authorized>
		<NotAuthorized>
			<MudLink Underline="Underline.None" Color="Color.Inherit" Href="/login" Class="mr-2">Login</MudLink>
			<MudLink Underline="Underline.None" Color="Color.Inherit" Href="/registration">Registration</MudLink>
		</NotAuthorized>
	</AuthorizeView>
</MudAppBar>
  • (Line: 5) The 'Weather Forecast' menu item.

Create DelegatingHandler In Blazor Application:

The DelegatingHandler helps to bypass the request. Here in our case, we want to add the authorization heder with jwt token as value.

Let's create a class like 'CustomHttpHandler.cs' in the 'Shared/Providers' folder.
BlazorWasm_Project/Shared/Providers/CustomHttpHandler.cs:
using Blazored.LocalStorage;

namespace JWT.Auth.BlazorUI.Shared.Providers
{
    public class CustomHttpHandler: DelegatingHandler
    {
        private readonly ILocalStorageService _localStorageService;
        public CustomHttpHandler(ILocalStorageService localStorageService)
        {
            _localStorageService = localStorageService;
        }
        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
        {
            if(request.RequestUri.AbsolutePath.ToLower().Contains("login") ||
                request.RequestUri.AbsolutePath.ToLower().Contains("registration"))
            {
                return await base.SendAsync(request, cancellationToken);
            }

            var jwtToken = await _localStorageService.GetItemAsync<string>("jwt-access-token");

            if (!string.IsNullOrEmpty(jwtToken))
            {
                request.Headers.Add("Authorization", $"bearer {jwtToken}");
            }

            return await base.SendAsync(request, cancellationToken);
        }
    }
}
  • (Line: 5) Implement the 'DelegatingHandler' abstract class.
  • (Line: 7-11) Injected the 'ILocalStorageService'.
  • (Line: 12-29) Override the 'SendAsync' method. For 'login' & 'registration' endpoint normal flow. For another endpoint request, we are adding the 'Authorization' header with the JWT token as a value.
Now register the handler in 'Program.cs'
BlazorWasm_Project/Program.cs:
builder.Services.AddHttpClient("API", options => {
    options.BaseAddress = new Uri("https://localhost:7045/");
})
.AddHttpMessageHandler<CustomHttpHandler>();

builder.Services.AddScoped<CustomHttpHandler>();

Implement Route Protection:

If the user is not authenticated and trying to consume secured pages then need to restrict access. If the user is authenticated and trying to consume pages like 'login', 'registration', etc then need to restrict access.

Let's create a new component like 'RedirectToLogin.razor'
BlazorWasm_Project/Shared/RedirectToLogin.razor:
<h3>RedirecToLogin</h3>
@inject NavigationManager _navigation
@code {
    protected override void  OnInitialized()
    {
        _navigation.NavigateTo("/login");
    }
}
  • Here we just redirecting to the 'Login.razor' component.
Now let's invoke the 'RedirectToLogin.razor' from 'App.razor'
BlazorWasm_Project/App.razor:
<CascadingAuthenticationState>
    <Router AppAssembly="@typeof(App).Assembly">
        <Found Context="routeData">
             <AuthorizeRouteView RouteData="@routeData" DefaultLayout="@typeof(MainLayout)">
                 <NotAuthorized>
                    @if (context.User.Identity?.IsAuthenticated != true)
                    {
                        <RedirecToLogin/>
                    }
                    
                 </NotAuthorized>

                 </AuthorizeRouteView>
            <FocusOnNavigate RouteData="@routeData" Selector="h1" />
        </Found>
        <NotFound>
            <PageTitle>Not found</PageTitle>
            <LayoutView Layout="@typeof(MainLayout)">
                <p role="alert">Sorry, there's nothing at this address.</p>
            </LayoutView>
        </NotFound>
    </Router>
</CascadingAuthenticationState>
  • (Line: 4-13) Configured the 'AuthoirzedRouteView' component, inside of it added not the 'NotAutherized' component. So if any user tries to access an au authorized page then content inside of 'NotAuthenticated' gets executed. Here we checking the user is authenticated or not if not authenticated then we invoke the 'RedireToLogin' component.
Now let's add 'Authorize' attribute on our 'FetchData.razor' component so that only authenticated users can consume the 'FetchData' page.
BlazorWasm_Project/Pages/FetchData.razor:
@using Microsoft.AspNetCore.Authorization;
@attribute [Authorize]
Now if the user is authenticated and tries to access the 'login' or 'registration' page then let's redirect user to home page. In our application home page is a guest page both authenticated and non-authenticated users can access. Now let's add the following code Login.razor and 'Registration.razor' pages
BlazorWasm_Project/Pages/Accounts/(Login.razor and Registraion.razor):
[CascadingParameter] 
public Task<AuthenticationState> authState { get; set; }

protected override async Task OnInitializedAsync()
{
	var user = (await authState).User;
	if (user.Identity.IsAuthenticated)
	{
		_navigationManager.NavigateTo("/");
	}
	base.OnInitializedAsync();
}
In the next article, we will implement the Refresh Token.

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Wrapping Up:

Hopefully, I think this article delivered some useful information on the.NET7 Blazor WebAssembly JWT Authentication. using I love to have your feedback, suggestions, and better techniques in the comment section below.

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  1. AnonymousJune 4, 2023 at 11:42 PM

    I am using your articles as a reference. When do you think you will publish the next one?

    Best regards and thank you in advance.

    ReplyDelete

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Angular 14 State Management CRUD Example With NgRx(14)

In this article, we are going to implement the Angular(14) state management CRUD example with NgRx(14) NgRx Store For State Management: In an angular application to share consistent data between multiple components, we use NgRx state management. Using NgRx state helps to avoid unwanted API calls, easy to maintain consistent data, etc. The main building blocks for the NgRx store are: Actions - NgRx actions represents event to trigger the reducers to save the data into the stores. Reducer - Reducer's pure function, which is used to create a new state on data change. Store - The store is the model or entity that holds the data. Selector - Selector to fetch the slices of data from the store to angular components. Effects - Effects deals with external network calls like API. The effect gets executed based the action performed Ngrx State Management flow: The angular component needs data for binding.  So angular component calls an action that is responsible for invoking the API call.  Aft
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Angular 14 Crud Example

In this article, we will implement CRUD operation in the Angular 14 application. Angular: Angular is a framework that can be used to build a single-page application. Angular applications are built with components that make our code simple and clean. Angular components compose of 3 files like TypeScript File(*.ts), Html File(*.html), CSS File(*.cs) Components typescript file and HTML file support 2-way binding which means data flow is bi-directional Component typescript file listens for all HTML events from the HTML file. Create Angular(14) Application: Let's create an Angular(14) application to begin our sample. Make sure to install the Angular CLI tool into our local machine because it provides easy CLI commands to play with the angular application. Command To Install Angular CLI npm install -g @angular/cli Run the below command to create the angular application. Command To Create Angular Application ng new name_of_your_app Note: While creating the app, you will see a noti
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Unit Testing Asp.NetCore Web API Using xUnit[.NET6]

In this article, we are going to write test cases to an Asp.NetCore Web API(.NET6) application using the xUnit. xUnit For .NET: The xUnit for .Net is a free, open-source, community-focused unit testing tool for .NET applications. By default .Net also provides a xUnit project template to implement test cases. Unit test cases build upon the 'AAA' formula that means 'Arrange', 'Act' and 'Assert' Arrange - Declaring variables, objects, instantiating mocks, etc. Act - Calling or invoking the method that needs to be tested. Assert - The assert ensures that code behaves as expected means yielding expected output. Create An API And Unit Test Projects: Let's create a .Net6 Web API and xUnit sample applications to accomplish our demo. We can use either Visual Studio 2022 or Visual Studio Code(using .NET CLI commands) to create any.Net6 application. For this demo, I'm using the 'Visual Studio Code'(using the .NET CLI command) editor. Create a fo
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Part-1 Angular JWT Authentication Using HTTP Only Cookie[Angular V13]

In this article, we are going to implement a sample angular application authentication using HTTP only cookie that contains a JWT token. HTTP Only JWT Cookie: In a SPA(Single Page Application) Authentication JWT token either can be stored in browser 'LocalStorage' or in 'Cookie'. Storing JWT token inside of the cookie then the cookie should be HTTP Only. The HTTP-Only cookie nature is that it will be only accessible by the server application. Client apps like javascript-based apps can't access the HTTP-Only cookie. So if we use authentication with HTTP only JWT cookie then we no need to implement custom logic like adding authorization header or storing token data, etc at our client application. Because once the user authenticated cookie will be automatically sent to the server by the browser on every API call. Authentication API: To implement JWT cookie authentication we need to set up an API. For that, I had created a mock authentication API(Using the NestJS Se
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ReactJS(v18) Authentication With JWT AccessToken And Refresh Token

In this article, we are going to do ReactJS(v18) application authentication using the JWT Access Token and Refresh Token. JSON Web Token(JWT): JSON Web Token is a digitally signed and secured token for user validation. The JWT is constructed with 3 important parts: Header Payload Signature Create ReactJS Application: Let's create a ReactJS application to accomplish our demo. npx create-react-app name-of-your-app Configure React Bootstrap Library: Let's install the React Bootstrap library npm install react-bootstrap bootstrap Now add the bootstrap CSS reference in 'index.js'. src/index.js: import 'bootstrap/dist/css/bootstrap.min.css' Create A React Component 'Layout': Let's add a React component like 'Layout' in 'components/shared' folders(new folders). src/components/shared/Layout.js: import Navbar from "react-bootstrap/Navbar"; import { Container } from "react-bootstrap"; import Nav from "react-boot
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A Small Guide On NestJS Queues

NestJS Application Queues helps to deal with application scaling and performance challenges. When To Use Queues?: API request that mostly involves in time taking operations like CPU bound operation, doing them synchronously which will result in thread blocking. So to avoid these issues, it is an appropriate way to make the CPU-bound operation separate background job.  In nestjs one of the best solutions for these kinds of tasks is to implement the Queues. For queueing mechanism in the nestjs application most recommended library is '@nestjs/bull'(Bull is nodejs queue library). The 'Bull' depends on Redis cache for data storage like a job. So in this queueing technique, we will create services like 'Producer' and 'Consumer'. The 'Producer' is used to push our jobs into the Redis stores. The consumer will read those jobs(eg: CPU Bound Operations) and process them. So by using this queues technique user requests processed very fastly because actually
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