Redis Backplane - AddStackExchangeRedis #6425

19 Answer(s)

• 

  0

  cmthomps created 5 years ago

  @ismcagdas - I got notifications working in a load balanced environment. What I found was that there maybe an issue with SignalRRealTimeNotifier in the Abp.AspNetCore.SignalR. In that code, there is a line that says:

  var signalRClient = _hubContext.Clients.Client(onlineClient.ConnectionId);
  

  If I change that line of code to:

  var signalRClient = _hubContext.Clients.All;
  

  I'll be completely honest, I don't really know why it works. I was going through Microsoft's example on the redis backplane and found this difference. When I changed it, it started working (at least in my initial tests).

  Save Cancel
• 

  0

  aaron created 5 years ago

  Support Team

  Does onlineClient.ConnectionId have a valid value?

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  It looks like the ConnectionId is valid. I starting logging the UserId and the ConnectionId. This what that looks like:

  UserID: 1 ConnectionId: wRX8xHl-XqgDsKZ8zGunNA
  

  When I use var signalRClient = _hubContext.Clients.Client(onlineClient.ConnectionId);, I do not see any activity on the redis server.  When I use Clients.All, I start to see activity on the Redis server that looks like:

  <br>

  1549554528.516258 [0 172.17.0.9:45157] "INFO" "replication"
  1549554536.048210 [0 172.17.0.1:61383] "PUBLISH" "smczeroSmc.Abp.AspNetCore.SignalR.Hubs.AbpCommonHub:all" "\x92\x90\x81\xa4json\xc5\x02E{\"type\":1,\"target\":\"getNotification\",\"arguments\":[{\"tenantId\":null,\"userId\":1,\"state\":0,\"notification\":{\"tenantId\":null,\"notificationName\":\"App.TestNotification\",\"data\":{\"message\":{\"sourceName\":\"SMCDemo\",\"name\":\"TestNotification\"},\"type\":\"Abp.Notifications.LocalizableMessageNotificationData\",\"properties\":{\"message\":{\"sourceName\":\"SMCDemo\",\"name\":\"TestNotification\"}}},\"entityType\":null,\"entityTypeName\":null,\"entityId\":null,\"severity\":2,\"creationTime\":\"2019-02-07T10:48:52.744841-05:00\",\"id\":\"4defe4c2-997f-4cc2-9368-fda4a8ec947d\"},\"id\":\"2aeb9a04-d11a-4118-8ef8-5e592b0b06ca\"}]}\x1e"
  1549554538.425415 [0 127.0.0.1:54504] "AUTH" "5NSAjVIyvGmfpBot"
  

  I don't really know what the implications are to using Clients.All.  Do you?

  Thanks, Craig

  Save Cancel
• 

  0

  aaron created 5 years ago

  Support Team

  Using Clients.All means sending it to all clients.

  According to aspnet/SignalR#2460, sending to a specific client should work.

  You can create a new issue referencing that here: https://github.com/aspnet/AspNetCore/issues/new

  Related: aspnet/AspNetCore#5358

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  Here's what seems to have fixed it for me. I don't really understand why, but it seems to work nonetheless.

  In the SendNotificationsAsync method, I changed the line that says:

  signalRClient.SendAsync("getNotification", userNotification);
  

  to

  _hubContext.Clients.Client(onlineClient.ConnectionId).SendAsync("getNotification", userNotification);
  

  Does that make any sense to you?  if I use the signalRClient object, it doesn't seem to send the notifications properly.

  Save Cancel
• 

  0

  aaron created 5 years ago

  Support Team

  No, it's the same.

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  Not sure. The first one does not work with Redis the second one does. I guess others will find this if they need it.

  I'd like to vote for AspNetZero to enhance the product to support scale out using load balancing. Given the popularity of kubernetes, having this capability will be extremely valuable. I've got it running on kubernetes now, but finding that notifications and chat do not work. We got notifications to work using the hack above and I'm trying to get chat working with Redis using the code developed by another user. Haven't had any luck yet with Chat. All credit to personball on github.

  RedisOnlineClientManager.cs

  Save Cancel
• 

  0

  aaron created 5 years ago

  Support Team

  Try reverting the change.

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  Thanks @aaron. You're right.... That leads me to my next question. As part of this, I've created my own module that represents the ABP SignalRRealTimeNotifier called SmcSignalRRealTimeNotifier. In there, I've defined a my own AbpCommonHub called SmcAbpCommonHub. The code in the module is exactly the same as what is in ABP (Abp.AspNetCore.SignalR/AspNetCore/SignalR/).

  When I use the AbpCommonHub in the Mvc startup.cs, the redis notifications do not work. When I override the SignalRRealTimeNotifier dependency with my own SmcSignalRRealTimeNotifier and use the SmcAbpCommonHub, the redis notifications start working. Can you think of a reason why that is?

  Save Cancel
• 

  0

  aaron created 5 years ago

  Support Team

  How are you:

  • subscribing on the client side, and
  • using SignalRRealTimeNotifier on the server side

  before and after switching to SmcSignalRRealTimeNotifier?

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  I made no changes to the client side of things. In the Web.Mvc project, I changed a couple of things:

  1. In the Startup.cs ConfigureServices method, I changed

              var signalrBuilder = services.AddSignalR();
  

  To

                  var signalrBuilder = services.AddSignalR();
                  signalrBuilder.AddStackExchangeRedis(_appConfiguration["SignalR:ConnectionString"], options => {
                          options.Configuration.ChannelPrefix = "smczero";
                          });
                  }
  

  1. In the Configure method, I changed

              app.UseSignalR(routes =>
              {
                  routes.MapHub<AbpCommonHub>("/signalr");
                  routes.MapHub<ChatHub>("/signalr-chat");
              });
  

  To

              app.UseSignalR(routes =>
              {
                  routes.MapHub<SmcAbpCommonHub>("/signalr");
                  routes.MapHub<ChatHub>("/signalr-chat");
              });
  

  The last thing I did was register the register the SmcSignalRRealTimeNotifier as IRealTimeNotifier in my Web.Core project which is where the new module code lives.

  Save Cancel
• 

  0

  aaron created 5 years ago

  Support Team

  You didn't answer any of the 2 questions, which were about usage and not configuration.

  If you're saying usage didn't change and the 2 replaced classes are subclasses that don't override or add any method, then they are pointless changes similar to assigning a variable as before.

  Try reverting those changes.

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  Here's a question for you. Have you tried to reproduce the issue I'm having on your machine with Redis and the StackExchangeRedis nuget package? When I run a straight, out of the box download of AspNetZero with no changes other than adding the StackExchangeRedis nuget package and adding the call to AddStackExchangeRedis in Startup.cs, the notifications do not work. Don't know what else to tell you.

  Save Cancel
• 

  0

  aaron created 5 years ago

  Support Team

  No, because it is not a problem with ASP<span></span>.NET Zero or ABP.

  Save Cancel
• 

  0

  ismcagdas created 5 years ago

  Support Team

  Hi @cmthomps

  Sorry for our late reply. Did you find any solution for this ? I just wanted to check before setting up such an environment to test this problem.

  Thanks,

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  Thanks @ismcagdas. I have a private github repository that I just shared with you. It contains an AspNetZero demo project that uses Redis for both Chat and Notifications. I've done some minimal testing. But it appears to work on Kubernetes running multiple pods behind a load balancer. Not sure if it's something that can be incorporated into the base product. For us, having the ability to run behind a load balancer is very important.

  Save Cancel
• 

  0

  ismcagdas created 5 years ago

  Support Team

  I got the invitation and I will try to check it on weekend.

  Thanks,

  Save Cancel
• 

  0

  ismcagdas created 5 years ago

  Support Team

  Hi @cmthomps

  Have you figure this problem out ? It seems like the team didn't have time to check this.

  Save Cancel
• 

  0

  cmthomps created 5 years ago

  Thanks @ismcagdas - Honestly, I have a workaround that seems to be working for us. The last time I checked, notifications do not work when using the StackExchange Redis Backplane but I have tried the v6.9.

  Craig

  Save Cancel