Event Handling in ASP.NET Core Blazor

<button @onclick="() => { counter += 1; }">Button1</button>
<button @onclick="Increment1">Button2</button>
<button @onclick="Increment2">Button2</button>

<div>
    <span>Count : </span>
    <span>@counter</span>
</div>

@code
{
    private int counter = 0;

    private void Increment1()
    {
        counter += 1;
    }

    private async Task Increment2()
    {
        await Task.Delay(1000);
        counter += 1;
    }
}

References
https://docs.microsoft.com/en-us/aspnet/core/blazor/components/event-handling

Data Binding in ASP.NET Core Blazor

<p>
    <input @bind="inputValue" />
</p>

<p>@inputValue</p>

@code {
    private string? inputValue;
}

Equivalent HTML binding

<p>
    <label>
        Normal Blazor binding: 
        <input @bind="InputValue" />
    </label>
</p>

<p>
    <label>
        Demonstration of equivalent HTML binding: 
        <input value="@InputValue"
            @onchange="@((ChangeEventArgs __e) => InputValue = __e?.Value?.ToString())" />
    </label>
</p>

<p>
    <code>InputValue</code>: @InputValue
</p>

@code {
    private string? InputValue { get; set; }
}

Bind a property or field on other Document Object Model (DOM) events

@page "/bind-event"

<p>
    <input @bind="InputValue" @bind:event="oninput" />
</p>

<p>
    <code>InputValue</code>: @InputValue
</p>

@code {
    private string? InputValue { get; set; }
}

References
https://docs.microsoft.com/en-us/aspnet/core/blazor/components/data-binding

Install NVIDIA 340.108 Driver on Ubuntu

Install NVIDIA proprietary drivers on Debian / Ubuntu / Linux Mint / LMDE and disable the nouveau driver

Make sure that you system is up-to-date and you are running latest kernel, also make sure that you don’t have any Debian / Ubuntu / Linux Mint / LMDE NVIDIA package installed

## Ubuntu / Debian / Linux Mint / LMDE ##
apt update

apt upgrade

## Debian and Linux Mint ##
apt autoremove $(dpkg -l nvidia-driver* |grep ii |awk '{print $2}')

## Ubuntu ##
apt autoremove $(dpkg -l xserver-xorg-video-nvidia* |grep ii |awk '{print $2}')

apt reinstall xserver-xorg-video-nouveau

Install needed dependencies

## Ubuntu / Debian / Linux Mint ##
apt install linux-headers-$(uname -r) gcc make acpid dkms libglvnd-core-dev libglvnd0 libglvnd-dev dracut wget patch libgtk2.0-0

Disable nouveau

Create or edit /etc/modprobe.d/blacklist.conf

Append ‘blacklist nouveau’

echo "blacklist nouveau" >> /etc/modprobe.d/blacklist.conf

Edit /etc/default/grub

Append ‘rd.driver.blacklist=nouveau’ to end of ‘GRUB_CMDLINE_LINUX=”…”‘.

## Example row on Debian ##
GRUB_CMDLINE_LINUX_DEFAULT="quiet rd.driver.blacklist=nouveau"

## OR with Ubuntu and Linux Mint ##
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash rd.driver.blacklist=nouveau"

Update grub2 conf

## BIOS and UEFI ##
update-grub2

Generate initramfs

## Backup old initramfs nouveau image ##
mv /boot/initrd.img-$(uname -r) /boot/initrd.img-$(uname -r)-nouveau
 
## Generate new initramfs image ##
dracut -q /boot/initrd.img-$(uname -r) $(uname -r)

Create new directory for inttf NVIDIA patcher

cd ~
mkdir NVIDIA
cd NVIDIA

Download / Update inttf NVIDIA patcher

wget -O inttf-nvidia-patcher.sh https://nvidia.if-not-true-then-false.com/patcher/inttf-nvidia-patcher.sh

Make inttf NVIDIA patcher executable

chmod +x inttf-nvidia-patcher.sh

Download and patch your drivers

./inttf-nvidia-patcher.sh -v 340.108

Reboot to runlevel 3

systemctl set-default multi-user.target

reboot

Run NVIDIA Binary

./NVIDIA-Linux-x86_64-340.108-patched-kernel-5.15.run
systemctl set-default graphical.target

reboot

References
https://www.if-not-true-then-false.com/2021/debian-ubuntu-linux-mint-nvidia-guide/
https://www.if-not-true-then-false.com/2020/inttf-nvidia-patcher/

Transient fault handling in gRPC with retries in C#

gRPC calls can be interrupted by transient faults. Transient faults include:

  • Momentary loss of network connectivity.
  • Temporary unavailability of a service.
  • Timeouts due to server load.

When a gRPC call is interrupted, the client throws an RpcException with details about the error. The client app must catch the exception and choose how to handle the error.

var client = new Greeter.GreeterClient(channel);
try
{
    var response = await client.SayHelloAsync(
        new HelloRequest { Name = ".NET" });

    Console.WriteLine("From server: " + response.Message);
}
catch (RpcException ex)
{
    // Write logic to inspect the error and retry
    // if the error is from a transient fault.
}

Duplicating retry logic throughout an app is verbose and error-prone. Fortunately, the .NET gRPC client now has built-in support for automatic retries. Retries are centrally configured on a channel, and there are many options for customizing retry behavior using a RetryPolicy.

var defaultMethodConfig = new MethodConfig
{
    Names = { MethodName.Default },
    RetryPolicy = new RetryPolicy
    {
        MaxAttempts = 5,
        InitialBackoff = TimeSpan.FromSeconds(1),
        MaxBackoff = TimeSpan.FromSeconds(5),
        BackoffMultiplier = 1.5,
        RetryableStatusCodes = { StatusCode.Unavailable }
    }
};

// Clients created with this channel will automatically retry failed calls.
var channel = GrpcChannel.ForAddress("https://localhost:5001", new GrpcChannelOptions
{
    ServiceConfig = new ServiceConfig { MethodConfigs = { defaultMethodConfig } }
});

References
https://devblogs.microsoft.com/dotnet/grpc-in-dotnet-6/
https://docs.microsoft.com/en-us/aspnet/core/grpc/retries?view=aspnetcore-6.0

gRPC client-side load balancing in C#

The following code example configures a channel to use DNS service discovery with round-robin load balancing:

var channel = GrpcChannel.ForAddress(
    "dns:///my-example-host",
    new GrpcChannelOptions
    {
        Credentials = ChannelCredentials.Insecure,
        ServiceConfig = new ServiceConfig { LoadBalancingConfigs = { new RoundRobinConfig() } }
    });
var client = new Greet.GreeterClient(channel);

var response = await client.SayHelloAsync(new HelloRequest { Name = "world" });

References
https://devblogs.microsoft.com/dotnet/grpc-in-dotnet-6/
https://docs.microsoft.com/en-us/aspnet/core/grpc/loadbalancing?view=aspnetcore-6.0