Wednesday, January 25, 2023

Visual Studio 2022: Sending HTTP Requests with .http Files

Do you know Visual Studio has this nice feature to send HTTP Requests using .http files. It's actually pretty neat.

We just have to create a file with .http extension.
.http Files in Action
We can do all the methods and the output is displaying nicely.

Disclaimer: I am not sure when this feature got added, I am on Microsoft Visual Studio Enterprise 2022 (64-bit) - Version 17.5.0 Preview 4.0 and I don't have a specific extension installed in order to enable this functionality.

Hope this helps!

Happy Coding.

Regards,
Jaliya

Wednesday, January 18, 2023

Visual Studio 2022 Version 17.5 Preview 2: Text Visualizer Improvements

In this post let's explore some nice improvements that got added to Text Visualizer in Visual Studio. This got shipped with Visual Studio 2022 Version 17.5 Preview 2

I actually found this accidentally and it's so handy!

Say I have a string variable that holds a JWT token and I want to decode it for some debugging purpose. Usually what I would do is copy-pasting the token into https://jwt.io or https://jwt.ms or some external JWT decoding tool. What if we can see the decoded token without leaving Visual Studio? And that's exactly what the new Text Visualizer brings to the table.

Say I want to see the decoded token of the following.
Debugging a string
I need to click on the View button. And then I am presented with the following.
Text Visualizer
I can just select JWT Decode and just like that I can see the decoded token. 

Along that, you can see there are more options to manipulate the string such as Base64 Encode & DecodeUrl Encode & Decode etc.

Isn't that great? I just love this. Remember, if you want to try this out, you need to install the latest Visual Studio 2022 Preview.

Hope this helps.

Happy Coding.

Regards,
Jaliya

Tuesday, January 10, 2023

Azure Durable Functions in Azure Functions .NET Isolated Worker Process

Azure Durable Functions now supports .NET 7.0 running in the Isolated worker process. It's still in it's preview stage, but it's super exciting.

In this post, let's see how we can get ourselves started in Azure Durable Functions in Azure Functions .NET Isolated Worker Process.

First, after creating a Function App that targets .NET 7 Isolated functions worker, we need to install the NuGet package: Microsoft.Azure.Functions.Worker.Extensions.DurableTask. Make sure you have checked Included prerelease checkbox if you are trying to install the package through Visual Studio NuGet Package Manager.

Microsoft.Azure.Functions.Worker.Extensions.DurableTask
After installing the package, I have updated Function1.cs as follows adding a simple Durable Function.
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.DurableTask;
using Microsoft.Extensions.Logging;
 
namespace FunctionApp1;
 
public class Function1
{
    [Function(nameof(TriggerHello))]
    public async Task<HttpResponseData> TriggerHello([HttpTrigger(AuthorizationLevel.Anonymous, "get")] HttpRequestData req,
        [DurableClient] DurableClientContext durableContext,
        FunctionContext executionContext)
    {
        ILogger logger = executionContext.GetLogger(nameof(Function1));
 
        string instanceId = await durableContext.Client.ScheduleNewOrchestrationInstanceAsync(nameof(HelloPersonOrchestrator));
        logger.LogInformation("Created new orchestration with instance ID = {instanceId}", instanceId);
 
        return durableContext.CreateCheckStatusResponse(req, instanceId);
    }
 
    [Function(nameof(HelloPersonOrchestrator))]
    public static async Task<stringHelloPersonOrchestrator([OrchestrationTrigger] TaskOrchestrationContext context,
        FunctionContext executionContext)
    {
        ILogger logger = executionContext.GetLogger(nameof(HelloPersonOrchestrator));
 
        string result = await context.CallActivityAsync<string>(nameof(SayHello), "John Doe") + " ";
        result += await context.CallActivityAsync<string>(nameof(SayHello), "Jane Doe") + " ";
        result += await context.CallActivityAsync<string>(nameof(SayHello), "Joe Bloggs") + " ";
        result += await context.CallActivityAsync<string>(nameof(SayHello), "Fred Bloggs");
 
        logger.LogInformation("HelloPersonOrchestrator says: {output}", result);
 
        return result;
    }
 
    [Function(nameof(SayHello))]
    public static string SayHello([ActivityTrigger] string name, FunctionContext executionContext)
    {
        ILogger logger = executionContext.GetLogger(nameof(SayHello));
        logger.LogInformation("Saying hello to {name}", name);
        return $"Hello {name}!";
    }
}
And then we can call the HTTP  trigger to start the orchestration. And it works like a charm.
Output
Can't wait for this to go under GA.

Do try this out and if you see any issues, please do not hesitate to log an issue here: microsoft/durabletask-dotnet

Hope this helps.

Happy Coding.

Regards,
Jaliya

Monday, December 5, 2022

ASP.NET Core Web API: Exception Handling

In this post, let's see how we can provide a common approach for handling exceptions in ASP.NET Core Web APIs in the Development environment as well as in Production environments.

It's quite easy, basically, we can introduce UseExceptionHandler Middleware to handle exceptions.

Consider the following code.
WebApplicationBuilder builder = WebApplication.CreateBuilder(args);
 
// Add services to the container.
builder.Services.AddControllers();
 
WebApplication app = builder.Build();
 
// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseExceptionHandler("/error-development");
}
else
{
    app.UseExceptionHandler("/error");
}
 
app.UseHttpsRedirection();
 
app.UseAuthorization();
 
app.MapControllers();
 
app.Run();
Here I have added UseExceptionHandler passing in different routes based on the environment. Now we need to define controller actions to respond to /error-development and /error routes.
using Microsoft.AspNetCore.Diagnostics;
using Microsoft.AspNetCore.Mvc;
using System.Net;
 
namespace WebApplication1.Controllers;
 
[ApiController]
[ApiExplorerSettings(IgnoreApi = true)]
public class ErrorController : ControllerBase
{
    private readonly IHostEnvironment _hostEnvironment;
 
    public ErrorController(IHostEnvironment hostEnvironment)
    {
        _hostEnvironment = hostEnvironment;
    }
 
    [Route("/error-development")]
    public IActionResult HandleErrorDevelopment()
    {
        if (!_hostEnvironment.IsDevelopment())
        {
            return NotFound();
        }
 
        IExceptionHandlerFeature exceptionHandlerFeature = HttpContext.Features.Get<IExceptionHandlerFeature>()!;
 
        if (exceptionHandlerFeature == null)
        {
            return Problem(
                title: $"'{nameof(IExceptionHandlerFeature)}' not found.");
        }
 
        return exceptionHandlerFeature.Error switch
        {
            NotImplementedException notImplementedException => Problem(
                title: notImplementedException.Message,
                detail: notImplementedException.StackTrace,
statusCode: (int)HttpStatusCode.NotImplemented), _ => Problem( title: exceptionHandlerFeature.Error.Message, detail: exceptionHandlerFeature.Error.StackTrace) }; } [Route("/error")] public IActionResult HandleError() => Problem(); }
Note: The actions aren't attributed with HttpVerbs and the controller is attributed with [ApiExplorerSettings(IgnoreApi = true)] to exclude from OpenAPI specification (if there's any).

For the Development environment, based on the type of the exception, I am returning different statusCodes and I am including the StackTrace to troubleshoot the issue easily. 

For an example, consider the following action.
[HttpGet(Name = "GetWeatherForecast")]
public IEnumerable<WeatherForecast> Get()
{
    throw new NotImplementedException("Not implemented.");
}
If we call the above action when running on a Development environment, I will be getting a response like below. It's the standard RFC 7807-compliant Problem Detail.
Development: StatusCode: 501
And now if I change the endpoint to throw a different exception,
[HttpGet(Name = "GetWeatherForecast")]
public IEnumerable<WeatherForecast> Get()
{
    throw new Exception("Something happened.");
}
I am getting the default Internal Server Error status code with the StackTrace.
Development: StatusCode: 500
And when in a production environment, we just get the response hiding internal details.
Production: StatusCode: 500

Hope this helps.

Happy Coding.

Regards,
Jaliya

Sunday, December 4, 2022

ASP.NET Core: Suppress Implicit Required Model Validation For Non Nullable Reference Types

In this post, let's see how we can disable implicit required model validation for non-nullable reference types when the nullable context is enabled in an ASP.NET Core Web Application.

Let's consider the following sample.

#nullable enable
 
using Microsoft.AspNetCore.Mvc;
 
WebApplicationBuilder builder = WebApplication.CreateBuilder(args);
 
// Register Services.
builder.Services.AddControllers();
 
WebApplication app = builder.Build();
 
// Configure the HTTP request pipeline.
app.UseHttpsRedirection();
 
app.MapControllers();
 
app.Run();

[ApiController]
[Route("[controller]")]
public class EmployeesController : ControllerBase
{
    [HttpPost]
    public ActionResult<EmployeeCreate([FromBodyEmployee employee)
    {
        return employee;
    }
}
 
public class Employee
{
    public string FirstName { getset; }
 
    public string LastName { getset; }
 
    public Employee(string firstNamestring lastName)
    {
        FirstName = firstName;
        LastName = lastName;
    }
}

Here if we try to post a payload with null values for reference types that are not marked with nullable, ASP.NET Core by default is doing a model validation and throwing an error.

For example, here if we post a payload without setting the value for LastName, I am getting the following error.
ASP.NET Core Model Validation
But there are times, we need to offload the validation to a separate module. In that case, we can easily suppress this validation as follows.
builder.Services.AddControllers(x =>
{
    x.SuppressImplicitRequiredAttributeForNonNullableReferenceTypes = true;
});
And then, we won't be seeing that validation anymore.
ASP.NET Core: Suppress Implicit Required Attribute For Non Nullable Reference Types
Hope this helps.

Happy Coding.

Regards,
Jaliya

Friday, December 2, 2022

JsonExtensionDataAttribute in System.Text.Json.Serialization

In this post let's have a look at this nice attribute JsonExtensionDataAttribute that's available in System.Text.Json.Serialization Namespace.

I had a requirement where I have an integration API that connects a client application with a third-party API. The client application is sending some JSON that needs to be sent to the third-party API as is, and at the same time, within the integration API, I need to intercept and read some values in the JSON. The JSON schema can be huge, and the Integration API doesn't really care about the full JSON schema. So how do we define a POCO class having the properties I really care about and let other properties get deserialized/serialized without any data loss.

Let's go by an example.

Consider the following JSON schema.

string jsonString =
    """
    {
        "_id": "57d0a0a676f943a4007e1525",
        "modified": "2022-09-07T23:20:06.949Z",
        "title": "Register",
        "display": "form",
        "type": "form",
        "name": "register",
        "path": "register",
        "components": [
            {
                "label": "First Name",
                "key": "firstName",
                "type": "textfield",
                "placeholder": "",
                "prefix": "",
                "suffix": "",
                "multiple": false
            },
            {
                "label": "Last Name",
                "key": "firstName",
                "type": "textfield",
                "placeholder": "",
                "prefix": "",
                "suffix": "",
                "multiple": false
            }
        ],
        "tags": []
    }
    """;

Now let's say, I only care about _idname and type properties.

I can create a POCO class, something like below.

public class Form
{
    [JsonPropertyName("_id")]
    public string Id { getset; }
 
    public string Name { getset; }
 
    public string Type { getset; }
}

But then the issue is, upon deserialization, I am going to lose some data. And this is where JsonExtensionDataAttribute comes in handy.

public class Form
{
    [JsonPropertyName("_id")]
    public string Id { getset; }
 
    public string Name { getset; }
 
    public string Type { getset; }
 
    [JsonExtensionData]
    public Dictionary<stringobject> JsonExtensionData { getset; }
}

Now when I deserialized the jsonString to Form what's going to happen is, the properties with matching members will get their values and the properties that do not have a matching member will get added to the JsonExtensionData dictionary.

JsonSerializerOptions jsonSerializerOptions = new()
{
    PropertyNamingPolicy = JsonNamingPolicy.CamelCase
};
 
Form form = JsonSerializer.Deserialize<Form>(jsonString, jsonSerializerOptions);

Here if I have a look at the form, it's going to look like this.

Deserialization
You can see that properties with matching members got their values and the rest went into the Dictionary.

And now when I serialize the form, the values in the Dictionary are written back as expected. 

string serializedString = JsonSerializer.Serialize(form, jsonSerializerOptions);
//{
//    "_id": "57d0a0a676f943a4007e1525",
//    "name": "register",
//    "type": "form",
//    "modified": "2022-09-07T23:20:06.949Z",
//    "title": "Register",
//    "display": "form",
//    "path": "register",
//    "components": [
//        {
//            "label": "First Name",
//            "key": "firstName",
//            "type": "textfield",
//            "placeholder": "",
//            "prefix": "",
//            "suffix": "",
//            "multiple": false
//        },
//        {
//            "label": "Last Name",
//            "key": "firstName",
//            "type": "textfield",
//            "placeholder": "",
//            "prefix": "",
//            "suffix": "",
//            "multiple": false
//        }
//    ],
//    "tags": []
//}

Isn't it nice?

Happy Coding.

Regards,
Jaliya

Thursday, December 1, 2022

C# 11.0: File-local Types

In this post let's have a look at one of the newest additions to C#, which is the file access modifier. 

For types that are declared with file access modifier, its visibility or scope is only limited to the file in which it's declared.

Consider the below code.

File1.cs

namespace MyNamespace;
 
file class MyClass
{
    public static void MyMethod()
    {
        //
    }
}

File2.cs

namespace MyNamespace;
 
file class MyClass
{
    public static void MyMethod()
    {
        //
    }
}

Here I have 2 classes with the same name and within the same namespace but in different files. With C# 11.0, this will build just fine. Prior to C# 11.0, we weren't able to do this.

file keyword can be applied only to the following types.

And it's allowed only at the top-level type. 

public class MyClass
{
    // Error: Not allowed as MyOtherClass is a nested type
    file class MyOtherClass
    { 
    
    }
}

It's very unlikely we will be using this file access modifier during business application development. But wanted to share it, because in case you see it, you know what it is.

More read:
   file (C# Reference)
   File-local types

Hope this helps.

Happy Coding.

Regards,
Jaliya

Wednesday, November 9, 2022

.NET: Using dotnet user-jwts to Create Development Time JWT Tokens

Hope you are enjoying .NET Conf 2022. It's such great content and another 2 more days to go. Don't miss it.

In this post, let's see how we can easily create JWT tokens for Development purposes using dotnet user-jwts

Consider the following code.
using System.Security.Claims;
 
WebApplicationBuilder builder = WebApplication.CreateBuilder(args);
 
// Add services to the container.
builder.Services.AddAuthentication()
    .AddJwtBearer();
 
builder.Services.AddAuthorization();
 
WebApplication app = builder.Build();
 
// Configure the HTTP request pipeline.
app.UseAuthorization();
 
app.UseHttpsRedirection();
 
app.MapGet("/", () => "Hello .NET");
 
app.MapGet("/me", (ClaimsPrincipal user) =>
    {
        return user?.Claims
            .Select(c => new { c.Type, c.Value })
            .ToList();
    })
    .RequireAuthorization();
 
app.Run();
So here, I have added the required services for Authentication/Authorization and have an endpoint that requires an authorized request. On a side note, here you can see I haven't specified the default authentication scheme when registering Authentication. We don't have to specify the default Authentication scheme anymore, if there is only one, it's automatically taken as the default and that's new with ASP.NET Core 7.0. 

Now back to the topic, how do we get a valid token for development purposes here easily?

We can use dotnet user-jwts to create JWT tokens and if we want, we can customize the token, like by adding different different scopes, claims, and so on, so we can dev test our authorization policies.

To get a valid token, we just need to run the following command from the Project directory.
dotnet user-jwts create
And this will give you an output like below.
dotnet user-jwts create
And at the same time, the command will update appsettings.Development.json, with few settings to validate the token in the Development environment.
{
  "Logging": {
    "LogLevel": {
      "Default""Information",
      "Microsoft.AspNetCore""Warning"
    }
  },
  "Authentication": {
    "Schemes": {
      "Bearer": {
        "ValidAudiences": [
          "http://localhost:35983",
          "https://localhost:44310",
          "http://localhost:5000",
          "https://localhost:7028"
        ],
        "ValidIssuer""dotnet-user-jwts"
      }
    }
  }
}
And now we can test the secured endpoint using a tool of our choice, passing the token that got generated under the Bearer scheme in the request's Authorization Header. If I use cURL, I can see I am getting authorized successfully.
Test the secured endpoint
That's pretty neat.

Read more about dotnet user-jwts command options to learn how you can customize the token.

Happy Coding.

Regards,
Jaliya

Tuesday, November 8, 2022

Visual Studio 2022: Enable Quick Add for Add New Items

In this post, let's go through a nice extension for Visual Studio 2022 that is soon going to be available within Visual Studio 2022 itself within Preview features.

The extension is Add New File (64-bit) and it's quite nice. 

Note: as of today, the latest preview of Visual Studio 2022 is 17.4.0 Preview 6.0, and this extension is still not available out of the box within Visual Studio, so you will have to download the extension and install it.

Once installed, you can do Shift + F2. When this is shipped with Visual Studio, the shortcut would be Ctrl + Shift + A.

And it's going to bring up this nice little dialog.
Add New Item
You can click on Show All Templates and still go back to the default dialog, or you can just add new items using this tiny dialog.

Say I want to add a new file at the root of the project, I can do something like below.
Add New Item
This will create the MyClass.cs file as a C# class file based on the extension.

A really nice thing is, I can do something like below.
Add Multiple Items
This will create a Services folder, and there it will create IMyService.cs and MyService.cs. And not only that, based on the naming convention of IMyService.cs, it will create an interface and not a class.
Files Created
That's pretty neat, isn't it? Do try this extension out. You can create folders, nested folders, and so on.

Can't wait to see this extension to be baked into Visual Studio 2022. Hopefully within this week (so much going on this week with .NET Conf 2022 coming up in just a couple of hours 😍) or in the next couple of weeks.

And watch the following video by Mads Kristensen to learn some cool features in Visual Studio 2022.
   Cool features in Visual Studio 2022

Happy Coding.

Regards,
Jaliya

Monday, November 7, 2022

Azure Logic App: HTTP Authentication with Azure AD

In this post let's see how easy it is to call REST API secured with Azure AD (or Azure AD B2C).

First, we need to select the Authentication type as Active Directory OAuth.

Then it's just a matter of entering the required information. 

Active Directory OAuth
Now, what are the values?
  • Authority: We can leave the Authority empty.Tenant: 
  • Tenant: TenaneId of the Azure Directory
  • Audience: We need to do an App Registration in the Azure AD, which you might have already done when setting up the REST API. If you haven't, you can follow the following guide, it's pretty in detail: Quickstart: Register an application with the Microsoft identity platform
  • Client ID: The Application (client) ID of the App Registration
  • Credential Type: Secret or Certificate (I have selected Secret for simplicity)
  • Secret: A secret you have generated under App Registration
Hope this helps.

Happy Coding.

Regards,
Jaliya