Azure Event Hubs >20 Subscribing Applications - azure

According to Azure's Documentation, Event Hubs are limited to 20 Consumer Groups.
I have a use case where I would like to broadcast an event to 50+ different 3rd party service. I have a processor for each, which combines the event with some other state, translate and send it out.
It is the same event received by all consumers so I do not think partitioning is relevant here.
How do I implement a large number of consuming services with Event Hubs? Am I doing it wrong? Is this a limitation of the way the Event Hubs client works?

I think you should consider implementing a Pub-Sub mechanism using Azure Service Bus, whether it's instead of the Events Hub or "after" it. It will allow to publish the event to all subscribed 3rd party services.
Take a look at Get started with Service Bus topics on how this might be implemented.
Hope it helps!

Related

How to think about useful integration scenarios using Event Grid and Service Bus together?

Summary
I'm trying to reason about a few integration patterns around using Azure Service Bus and Event Grid in the context of a microservices-based architecture. I like service bus for the transaction support, load leveling, sessions and so on. Just looking for feedback on the way I'm reasoning about them being used together for internal microservice communication and also provide events to external partners via webhooks.
Option 1
Say I already use service bus for microservices communication, but I would also like to publish to event grid to support publishing via webhooks to partner services outside my trust boundary. I'm thinking to have an Azure function (or similar) to receive my custom service bus topic events and the publish them to Event Grid.
This would also allow for the webhook event to be different than the internal events.
Is there any other option (e.g., some service bus premium feature) that could provide that integration out-of-the-box (ootb)? I'm only aware of service bus system events being pushed to Event Grid ootb.
Option 2
Have your microservices publish events only to Event Grid and then have Event Grid events pushed to your service bus topic. It would allow the webhook option in certain cases without much extra, but it seems odd for all my microservices to publish to Event Grid if I need to them have that generally pushed to service bus for load leveling and so on.
I would rather use service bus for my microservice communication. There are other drawbacks as well. It would only seem to make the webhook option a little more straightforward.
Option 3
Have the event publisher that wants to send webhook-related events publish to both Event Grid and service bus. This seems like a really bad idea and generally clumsy, even if you were able to abstract it away somewhat in code. It seems like it would be a worse version of option 1.

EventGrid vs EventHub

I am working on a service fabric application and want to publish few events from this application and subscribe or process those publish events in another application.
I have tried EventGrid concept and observed that there is a delay while publishing and processing the events. So, now I am looking for other alternatives like EventHub or Queues, etc..
If anyone had already used EventGrid, EventHud or Queues, etc.. , Please do suggest which one will give more performance when we deal with more events.
Design Approach
We have migrated the tables from SQL service to Service Fabric. There is a view in SQL Service, and we are planning to implement that as a service in service fabric.
The implementation logic follows below.
Table 1 implemented service and we publish an event for each CRUD operation to EventGrid/ EventHud.
Table 2 implemented service and we publish an event for each CRUD operation to EventGrid/ EventHud.
We have created a view service where it listens to the events when any event sent to EventGrid/ EventHud, it will perform required calculations and store in the ViewService( It is a background job)
We are looking for a messaging service which gives more performance.
Have you seen this comparison and this one?
Anyway, can you clarify your requirements in terms of throughput and performance? It depends on a lot of factors including, but not limited to, the message size and the amount of messages.
Having used both Event Grid and Event Hub I'd say Event Hub works very well for many messages per second, say data streams from iot devices, but the performance of the downstream processing can be a bottleneck. You have to process them very fast in order to receive new events. Then there are partitions and consumer groups that can be of help to balance the load and have different processors for the same data but with different view of the data stream. (A fast processor for live displaying of sensor data and a slower one for storing the data for later analysis)
If you're talking about a few events generated by an application that triggers other apps to start doing some work based on those events Event Grid is a good fit. I haven't experienced much delay in receiving those events.
But bottom line, I think all services (Event Grid, Event Hub, Service Bus etc) support different use cases and that should be your first decision point.
Can you describe your publisher, subscriber, etc. and show your metrics of the Azure Event Grid usage?
You can use the portal screen snippets on the topic (publisher) and subscription (subscriber).
The following screen snippets are from my tester when manually have been fired few events.
Publisher side:
Subscriber side:
Metrics on the portal:
As you can see, the delivery destination processing time is ~1ms. The latency time on the publisher side (custom topic) is between 2-4ms.
Note, that the AEG is a PUSH->PUSH-ACK or PUSH->PULL-ACK eventing loosely decupled Pub/Sub model instead of the Event Hub model which is based on the PUSH->PULL mechanism, in other words, the Event Hub needs to host a listener and receiver for pulling an event from the partition.

Send messages to clients using Azure Service Bus - Topics

Using Azure Service Bus - Topics, I want to implement a solution wherein messages are sent/notified to end consumers once the producer sends the message to Topic (like Queues).
I understand that Topics work as Pub/Sub model wherein subscribers need to read messages from subscriptions. But I'm looking for a workaround that works some what similar to Queue (where it triggers a web job / service when any message is received).
I have few thoughts like
1. Using Auto-Forwarding in subscriptions to forward messages to Queues but again I think if this kills the purpose of Topics
2. Schedule a job to process these requests but again I think if I'm delaying the process
First, I want to know if Service Bus Topic is right option to go with? Next, If possible to implement a workaround what is the best/better way?
PS: I have to send messages which has information - I guess I can't use Relays
Just to be clear, Queues and Topics in Service Bus are different. As you noted, Topics are useful in publish/subscribe scenarios.
Since you are looking for something that gets triggered, Azure functions might be what you need.
Azure Functions supports trigger and output bindings for Service Bus
queues and topics
https://learn.microsoft.com/en-us/azure/azure-functions/functions-bindings-service-bus
I think that #William is right, you can use/attach other process to the subscription to make what you trying to do.
he mentioned Azure Functions which is a good tool and I want to suggest Azure Logic Apps as well in case you want to take some decisions based in the message that you received.
With Azure Logic Apps you can create a logic Workflow and integrate many services using connectors provided by this tool.
You will find more in:
https://learn.microsoft.com/en-us/azure/connectors/connectors-create-api-servicebus
And for answer your question
First, I want to know if Service Bus Topic is right option to go with?
The quick answer is yes, using messaging patterns is the best way to create reliable solutions.
In your case you want as well notify another system after receiving a message.
The only thing that you need to be aware is, whenever you did not receive the notification what you'll do? you need to think about this scenario.
From discussion above.
Azure functions with Queues/Topics
Regardless of queues or topics. you can trigger azure function with both. This function will process the message . Now you can create two methods in same function SendEmail(), sendPhoneNotifcation() and parrellize the tasks using C# task parallel library. So same function will do both tasks in parallel.
Every time you get a message , your function is triggered. Process the message and notify user. The benefit is this function will scale automatically if you have large number of message coming through queue.

Should I change how our microservices communicate?

Our application consist of 7 microservices that have some intercommunication. Currently we're using simple storage queues that a microservice publish events to (the number of events is relative low). Then we have a azurefunction for each queue that might call another microservices. This is working fine for us right now the services uses about 20 queues with a corresponding function.
Now we need to handle an blobstorage event, and I did some googling and a started to get really confused. Suddenly there was a lot of questions:
Should we switch to Azure Event Grid
It handles blobstorage without any limitations (functions blobstorage trigger has some)
It allows for multiple subscribers (storage queues does not)
It has a lot of fuz - maybe this is the new recommended way
I like the idea of one central thing, but it reminds me a bit about biztalk...
Should I switch to Azure Service Bus
It has a nice tool (ServiceBusExplorer) for monitoring the queues and listners, and I could to a repost of any failed events
It visulizes my azure functions subscribers nicely
Should I continue with only storage queues
A bit difficult to monitor, but it works nice
I'll be really thankful for any advice or insights to this question.
Thanks
EventGrid is great when you have notifications floating to multiple subscribers. Is that the case for you?
An example would be deferring messages. With queues you can defer a message, not with EventGrid. Whenever to choose Storage Queues or Service Bus depends on the specific requirement that you have. Do you need de-duplication? Or ordered delivery? If you do, Service Bus is the way. Otherwise Storage Queues is enough.
First of All, I would like to recommend these two articles, it will clarify most of your doubts about these services:
Choose between Azure services that deliver messages
Storage queues and Service Bus queues compared
Regarding Event Grid, it acts like a bridge between the publisher and the subscriber, where publisher will send messages and forget whether it has been processed or not, and the Event Grid will handle the retry if the receiver\subscriber does not acknowledge that it was processed successfully.
As you mentioned, storage queues has limitations, as such blob triggered functions, and maybe Service Bus, but it will depend on your design requirements. I would like to point out some things you might consider before moving to Event Grid.
Storage queues & Service Bus does not care about your message schema, in Event Grid you have to create a custom event based on their schema to wrap your event, so the publisher and subscriber has to understand Event Grid for that, not that is a big deal, but now you have both sides coupled to Event Grid.
If you want to send the event straight to your micro-service, you have to implement the subscription validation in your service, otherwise the service won't be able to receive the events
Event Grid only retry the delivery of your messages for 24 hours, if your service is down or not process the message correctly for longer than 24h, it will make the event dead. Currently, there is no way to query dead messages. Storage Queues and Service Bus are configurable how long you keep the message and it can be kept for many days.
Your service web-hook must acknowledge the receipt(http 200 or 202) of an event within 60 seconds, otherwise it will consider failed. If your operation is longer that that, you should send it to a queue and handle the locking from your service.
Probably there are more limitations, but these are the ones I remember right now that might change anytime soon, I think Event Grid is a great technology still on early days, and there is much to improve, I would recommencement only as a hub for Azure management events, I don't think it is ready for use as an application integrator.
Regarding your comment for queue manager, for Service Bus your have the Service Bus Explorer, and for Azure Storage you have the Azure Storage Explorer, where you can check the messages in the queue, is not the same as Service Bus, but helps.
It very much depends on how are you consuming the queue messages, you can take a look at this comparison: https://learn.microsoft.com/en-us/azure/service-bus-messaging/service-bus-azure-and-service-bus-queues-compared-contrasted
If you don't need ordering and if you don't have a strong limit on message volume, size or TTL, you can stick to storage queues.

Azure Service Fabric routing

I would like to get some recommendation, for designing a routing of IoT messages in Azure.
I have following scenario:
Senors sending messages to Azure IoT Hub in Google Protobuf format. Depending of the type of a message, I want to route the message to different applications inside a service fabric.
My current approach is to use a service fabric application to receive all messages from the IoT hub, parse the protobuf message, send the message depending on their type (attribute inside the protobuf) to an type-specific Azure event hub. Now the applications fetches the messages from their "own" event hub and process the messages.
I'm not sure if this is the best approach. I don't like the fact, to have one event hub for each type of message. Service Bus Topics are probably not an option, because I have a lot of messages (~30k per second).
Do I realy need a event hub, to decoupling this process, or does it make sense, to send the messages from the "routing application" direct to the different "type applications"?
What do you think?
Regards,
Markus
If you really need high performance you should take a look at IoT Hub and Event Hubs. Azure Event Hubs is a highly scalable data streaming platform and event ingestion service capable of receiving and processing millions of events per second. Event Hubs can process and store events, data, or telemetry produced by distributed software and devices. Data sent to an event hub can be transformed and stored using any real-time analytics provider or batching/storage adapters.
In other hand if you need only 30k messages per second you can go with Premium Messaging.
Comparison of Azure IoT Hub and Azure Event Hubs
Premium Messaging: How fast is it?
What is Event Hubs?

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