How to Use KurrentDB for Event Sourcing in C# on Azure

				
					using KurrentDB.Client;
using KurrentDB.Client.Core.Serialization;

var server = "[ServerAddress]";

var settings = KurrentDBClientSettings.Create($"esdb://{server}?tls=false");

settings.OperationOptions.ThrowOnAppendFailure = false;

await using var client = new KurrentDBClient(settings);

var events = new List<object>
{
    new NewOrderCreated
    {
      Id = Guid.NewGuid(),
      CustomerID = Guid.NewGuid(),
      SalesPersonID = Guid.NewGuid(),
      SalesPersonName = "John Doe"
    },
    new OrderCancelled
    {
      Id = Guid.NewGuid(),
      Reason = "Customer changed their mind"
    },
    new ProductAddedToOrder
    {
      Id = Guid.NewGuid(),
      ProductId = Guid.NewGuid(),
      ProductName = "Laptop",
      Quantity = 1,
      PricePerUnit = 1200.00m
    },
    new ProductRemovedFromOrder
    {
      Id = Guid.NewGuid(),
      ProductId = Guid.NewGuid()
    }
};

var streamName = "order-12345";

await AppendEventsAsync(client, streamName, events);


async Task AppendEventsAsync(KurrentDBClient client, 
                             string stream, 
                             List<object> events)
{
    // Map the events to KurrentDB message type.
    var messages = events
        .Select(e => Message.From(data: e,
                                  messageId: Uuid.NewUuid())).ToList();

    await client.AppendToStreamAsync(streamName: stream, 
                                     messages: messages);
}

// Event definitions

public class NewOrderCreated
{
    public Guid Id { get; set; }
    public Guid CustomerID { get; set; }
    public Guid SalesPersonID { get; set; }
    public string? SalesPersonName { get; set; }
}

public class OrderCancelled
{
    public Guid Id { get; set; }
    public string? Reason { get; set; }
}

public class ProductAddedToOrder
{
    public Guid Id { get; set; }
    public Guid ProductId { get; set; }
    public string? ProductName { get; set; }
    public int Quantity { get; set; }
    public decimal PricePerUnit { get; set; }
}

public class ProductRemovedFromOrder
{
    public Guid Id { get; set; }
    public Guid ProductId { get; set; }
}