About

IDNT AppBasics are a series of basic application components created by IDNT. They are used within our internal PaaS and SaaS infrastructure as well as for several other public and private projects. Feel free to use these components within your own application.

This component

This component provides a .NETish interface to the libvirt virtualization API [https://libvirt.org]. The library is based on the raw Libvirt Bindings [https://libvirt.org/git/?p=libvirt-csharp.git] developed by Arnaud Champion, Jaromír Červenka and contributors. This project extends the bindings with rich functionality with a .NETish fluent interface.

The code runs fine on mono and dotnet core (tested with mono 6.8 and dotnet-sdk 3.1 on RHEL 8). All operations are thread-safe.

Nuget package

NuGet packages are available at https://www.nuget.org/packages/IDNT.AppBasics.Virtualization.Libvirt

Install-Package IDNT.AppBasics.Virtualization.Libvirt

The package is available for NETCoreApp 3.1, NETFramework 4.7, NETStandard 2.0. The dependcy on System.Drawing.Common is required for converting console screenshots to the specified destination format.

Documentation

See examples/ConsoleCore to see the basic usage. For configuration options see the fluet interface of LibvirtConnection.Create.

Example 1

The following code will output a list of domains and storage pools. Thereafter it waits for domain events like stopped, started, ... until you hit ENTER.

private static void Connection_DomainEventReceived(object sender, VirDomainEventArgs e)
{
    var domain = (LibvirtDomain)sender; // Note: this is null on undefine event
    Console.WriteLine($"EVENT: {e.UniqueId} {domain?.Name} {e.EventType}");
}

static void Main(string[] args)
{
    using (var connection = LibvirtConnection.Connect())
    {
		Console.WriteLine();
		Console.WriteLine("[DOMAINS]");
		
		foreach (var domain in connection.Domains)
		{
			Console.WriteLine($"{domain.UniqueId} {domain.Name} {domain.State}");
		}

		Console.WriteLine();
		Console.WriteLine("[STORAGE POOLS]");
		
		foreach (var domain in connection.StoragePools)
		{
			Console.WriteLine($"{domain.UniqueId} {domain.Name} {domain.State}");
		}

        Console.WriteLine();
        Console.WriteLine("Waiting for domain lifecycle events...");
        connection.DomainEventReceived += Connection_DomainEventReceived;

        Console.WriteLine();
        Console.WriteLine("[ENTER] to exit");
        Console.ReadLine();
    }
}

Example 2

Getting the domains CPU utilization in percent is as easy as:

    using (var connection = LibvirtConnection.Create.WithLocalAuth().Connect())
    {
		var d = domain in connection.Domains.Where(t => t.Name == 'MyVM').First();
		
		while(! Console.KeyAvailable)
		{
		    Console.WriteLine($"{d.Name}'s CPU Utilization = {d.CpuUtilization.LastSecond}%");
		    Thread.Sleep(1000);
		}
	}

Example 3

You need a screenshot of a domains console? Here you go:

    using (var connection = LibvirtConnection.Create.WithOpenAuth("user", "pass").Connect("@"qemu:///system"))
    {
		var d = domain in connection.Domains.Where(t => t.Name == 'MyVM').First();
		
		using(var fs = new FileStream("image.jpg", FileMode.Create))
			d.GetScreenshot(fs, System.Drawing.Imaging.ImageFormat.Jpeg);
	}

License

This code is licensed under the GNU Lesser General Public Library, Version 2.1 (the "License"). You may obtain a copy of the License at https://www.gnu.org/licenses/lgpl-2.1.en.html

Copyright

The original libvirt-csharp code was written by Arnaud Champion and Jaromír Červenka and can be found at https://libvirt.org/git/?p=libvirt-csharp.git

Contributions

The libvirt-dotnet repository is maintained by IDNT [https://www.idnt.net/]

Contributions of all kinds are always welcome.