Redis Stream I need Event Driven Architecture,

Question

When any new message received in the stream, on that time OnMessageReceived event should trigger.

public event EventHandler<MqMessageReceivedEventArgs> OnMessageReceived;


var result = await redisDatabase.StreamRangeAsync(StreamName, "-", "+", 1, Order.Ascending);

  protected virtual void OnMessageReceivedEvent(MqMessageReceivedEventArgs e)
  {
      OnMessageReceived?.Invoke(this, e);
  }

Answer 1

According to official documentation, you have to do the following:

Define pasing function:

public static class RedisHelper
{
    Dictionary<string, string> ParseResult(StreamEntry entry) => 
        entry.Values.ToDictionary(x => x.Name.ToString(), x => x.Value.ToString());
}

Start consumer task:

var tokenSource = new CancellationTokenSource();
var token = tokenSource.Token;

var readTask = Task.Run(async () =>
{
    while (!token.IsCancellationRequested)
    {
        var result = await db.StreamRangeAsync(streamName, "-", "+", 1, Order.Descending);
        if (result.Any())
        {
            var dictionaries = result.Select(r => ParseResult(r)).ToList();
            // or invoke event in loop
            OnMessageReceivedEvent(new MqMessageReceivedEventArgs(dictionaries))
        }

        await Task.Delay(1000);
    }
});

Answer 2

looks like you are trying to call/trigger OnMessageReceivedEvent, when this called a event with new msg will receive in stream. asuming logic already implemented and it listen for msg in stream.

public async Task ListenForMessages()
{
    while (true)
    {
        var result = await redisDatabase.StreamRangeAsync(StreamName, "-", "+", 1, Order.Ascending);
        if (result.Length > 0)
        {
            foreach (var message in result)
            {
                OnMessageReceived?.Invoke(this, new MqMessageReceivedEventArgs(message));
            }
        }
        await Task.Delay(1000); // Delay before checking for new messages again
    }
}
public class MqMessageReceivedEventArgs : EventArgs
{
public MqMessageReceivedEventArgs(StreamEntry message)
{
    // Initialize any properties you want to pass along with the event
}
}