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Deploy .NET Apps

.NET is a programming language family popularly used within Microsoft ecosystem, which includes C#, VB and F# languages. .NET is served as an compile language, which means you need to compile your code before running it.

There is no default dotnet compiler at system level. You have to install it first through deployment scripts.

warning

Serving .NET apps requires to be run via GLS, that's mean you have to listen from given PORT env/args.

Example​

The deployment script below installs the latest dotnet compiler and writes Program.cs and run it directly.

https://github.com/domcloud/recipes/blob/master/dotnet.yml
source: clear
features:
  - dotnet latest
nginx:
  root: public_html/public
  passenger:
    enabled: "on"
    app_start_command: env PORT=$PORT dotnet run
commands:
  - dotnet new console --name App
  - filename: Program.cs
    content: |
      using System.Text;
      using System.Net;
      class HttpServer
      {
          public static HttpListener listener = new();
          public static string pageBody = @"      
          <!DOCTYPE html>
          <html>
          <head>
              <title>DotNet App</title>
              <link rel=""stylesheet"" href=""//unpkg.com/bootstrap/dist/css/bootstrap.min.css"">
          </head>
          <body class=""p-5 text-center"">
              <p><img src=""//images.unsplash.com/photo-1465153690352-10c1b29577f8?fit=crop&w=200&h=200"" 
                  class=""img-fluid rounded-circle""></p>
              <h1 class=""mb-3"">Hello, world!</h1>
              <p>Serving from DotNet version {0}</p>
              <p class=""text-muted"">DOM Cloud</p>
          </body>
          </html>
          ";


          public static async Task HandleIncomingConnections()
          {
              string version = Environment.Version.ToString();
              byte[] pageData = Encoding.UTF8.GetBytes(string.Format(pageBody, version));
              while (true)
              {
                  // Will wait here until we hear from a connection
                  HttpListenerContext ctx = await listener.GetContextAsync();

                  // Peel out the requests and response objects
                  HttpListenerResponse resp = ctx.Response;

                  resp.ContentType = "text/html";
                  resp.ContentEncoding = Encoding.UTF8;
                  resp.ContentLength64 = pageData.LongLength;

                  await resp.OutputStream.WriteAsync(pageData);
                  resp.Close();
              }
          }

          public static void Main(string[] args)
          {
              // Create a Http server and start listening for incoming connections
              string? port = Environment.GetEnvironmentVariable("PORT") ?? "3000";
              listener.Prefixes.Add($"http://localhost:{port}/");
              listener.Start();
              Console.WriteLine("Listening for connections on localhost:{0}", port);

              // Handle requests
              Task listenTask = HandleIncomingConnections();
              listenTask.GetAwaiter().GetResult();

              // Close the listener
              listener.Close();
          }
      }

Existing .NET projects​

Existing Dotnet projects can run directly from source code. This eliminates the need to compile the code into a binary, although startup time may be a little bit slower to start.

https://github.com/domcloud/recipes/blob/master/dotnet-gls.yml
features:
  - dotnet lts
nginx:
  root: public_html/public
  passenger:
    enabled: "on"
    app_start_command: env PORT=$PORT dotnet run

Use other .NET versions​

To switch dotnet version use feature syntax like dotnet latest, dotnet 0.9.0, etc. Check your current dotnet version using dotnet --version in SSH.

features:
  - dotnet 0.9.0

.NET install scripts is powered by dotnet-install script.

App Management​

Your app do not restarted automatically after file changes. To restart, run restart via SSH.

Environment variables can be set either using NGINX's env_var_list or ~/.bashrc. Usually your language framework also reads .env files.

See NGINX and App Daemon for more information about NGINX and App managements including restarting, environment variables, and other global limitations.

App Logging​

You can see app log from Check -> Check Process Logs tab. Only startup problems displayed in the browser.

Please use a proper logging mechanism such as the standard logging library then write it to a log file, or any other solution that suits you.

NGINX errors and traffic logs can be examined via Webmin or Check -> Check Process Logs tab.