Centralize Request Configuration in .NET

Kiet Ly — Sun, 04 May 2025 16:36:53 +0000

These days in the .NET world, it's common to work with external services that require authentication or specific header configurations to function properly. Trust me—you don’t want to repeat the same setup logic everywhere you use HttpClient.

That’s where the DelegatingHandler class from the .NET library becomes incredibly useful.

A DelegatingHandler lets you intercept and modify HTTP requests before they are sent to the external service. This gives you the flexibility to apply required configurations like setting headers.

Just follow these 3 simple steps:

Create a custom handler

    // Create a handler derived from DelegatingHandler
    public class AuthHandler : DelegatingHandler
    {
        // Override SendAsync
        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
        {
            // Configure required header before actual request
            string token = await GetAccessTokenAsync();
            request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
            request.Headers.Add("Type", "INTERNAL");

            return await base.SendAsync(request, cancellationToken);
        }
    }

builder.Services.AddTransient<AuthHandler>();
builder.Services.AddHttpClient("VendorApi", client =>
{
    client.BaseAddress = new Uri("https://vendor.com");
})
.AddHttpMessageHandler<AuthHandler>();

Inject and use HttpClient throughout your code—without worrying about repeating header logic

app.MapGet("posts", async (IHttpClientFactory httpClientFactory) =>
{
    HttpClient httpClient = httpClientFactory.CreateClient("VendorApi");

    HttpResponseMessage response = await httpClient.GetAsync("posts");
    response.EnsureSuccessStatusCode();

    return await response.Content.ReadAsStringAsync();
})
.WithName("posts")
.WithOpenApi();

Learn more about DelegatingHandler and IHttpClientFactory here: https://learn.microsoft.com/en-us/aspnet/core/fundamentals/http-requests?view=aspnetcore-9.0

Write better comments in VS Code

Kiet Ly — Mon, 04 Sep 2023 03:53:17 +0000

During development, we often add comments to our code as notes.
These can include testing technologies, identifying areas for improvement, waiting for backend data or receiving feedback from mentors, often commenting like this:

form.addEventListener("submit", function (e) {
    e.preventDefault();

    // Validate email required
    // TODO: Improve the add class 'has-error' by using toggle
    if (txtEmail.value === "") {
      if (!txtEmail.classList.contains("has-error")) {
        txtEmail.classList.add("has-error");
      }
      spErrorMessage.innerText = "Email is required";
      spErrorMessage.style.display = "block";
      return;
    }

    // Validate email syntax
    // TODO: Improve the add class 'has-error' by using toggle
    let regex = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/;
    if (regex.test(txtEmail.value) === false) {
      if (!txtEmail.classList.contains("has-error")) {
        txtEmail.classList.add("has-error");
      }
      spErrorMessage.innerText = "Valid email required";
      spErrorMessage.style.display = "block";
      return;
    }

    // If success then show popup success
    // Delete this and replace with new function
    showPopup();
  });
});

As you can see, all the comments have the same color. Imagine these comments in a pile of code 😱. It would be difficult to determine which comment describes which part of the code. This could lead to mistakes or confusion. The Better Comments extension was created to address this issue.

Better Comments Extension

This extension will highlight special comments, allowing you to easily distinguish them from other comments

If the default color of the extension matches the color of your code editor, you can easily configure the color.

In addition, this extension also helps you to classify and write comments more organized and controlled.

Currently, this extension supports almost all programming languages. Give it a try and let me know your thoughts in the comments.
Thank you for reading my article, and have a great day! 🥰

Forem: Kiet Ly

Centralize Request Configuration in .NET

Write better comments in VS Code

Better Comments Extension