0

I am exploring the Azure IoT central rest APIs to create a custom Angular client. Is this possible or does it have any limitations? IoT Central is attractive due to its pricing. Specifically, I found that retrieving multiple telemetry values isn't possible as per the following documentation page. Which means you have to send individual "get" requests to fetch multiple telemetry.

Azure IoT Central (get telemetry value)

Is there a possibility to register a call back and receive regular updates of the values like in event hubs? Basically I want to develop a custom client facing app with the IoT Central Pricing. Is it possible?

Subbu
  • 588
  • 1
  • 7
  • 18
  • you can use a *Data Export* feature for continuously export data to the Azure Event Hub. – Roman Kiss Apr 23 '20 at 06:59
  • btw. few questions: how many devices will be connected to the IoTC App, how many messages will handle devices per day, do you need a command for device? – Roman Kiss Apr 23 '20 at 07:06

1 Answers1

0

It is possible, to receive regular updates on telemetry you can use continuous data export. You can export to Service Bus, Event Hubs and Blob Storage. See the documentation here on how to set that up. You can receive those events in any JavaScript application.

Please be aware that continuous data export will give you updates from all devices. If you need to filter them out you will need to build something to filter that out. One example I have built in the past is a .NET Core application that listens to the messages and sends that to the different clients over SignalR.

Matthijs van der Veer
  • 3,865
  • 2
  • 12
  • 22
  • I already knew that I could forward the messages to other end points using data export, but, then I will have to subscribe to other services which will add to the costs, whether it be Event Hub or blob storage right? Instead if the IoTC let us register a call back and exposed rest apis to read from its storage that it uses to store the values for 30 days, it would have been straightforward. We could have accessed all data like telemetry or alarms etc. I think in the above comments and your answer the pricing part lost focus. May be it wont fit into azures pricing if they did this? – Subbu Apr 23 '20 at 13:27
  • If you want this functionality without adding any paid services I think that's not possible at this moment. You can raise a feature request with Microsoft. The only way I think you might fit this in for free is to use the IoT Central ruling engine to call a Function as long as you stay within the free limits of Azure Functions. Sorry if that's not helpful, it seems we indeed lost focus of your goal to match IoT Central's pricing. – Matthijs van der Veer Apr 23 '20 at 16:53
  • No worries at all, in fact thanks a lot for the replies. I was thinking of raising a feature request too. Thanks for the effort. All this because I really think IoTC is great but the UI is not upto the mark with what is possible these days also I am an Angular fan and IoTC uses react I believe. So cant afford the learning curve either. – Subbu Apr 23 '20 at 17:15
  • @Subbu, thanks for the feedback. As mentioned above, continuous data export is the best way to achieve this at the moment; however, we (IoT Central team) are actively looking at improving our telemetry query APIs to allow you to query more than 1 datapoint at a time. In addition, we are also looking at enabling webhook capability within our continuous data export pipeline that will allow you to register for callbacks as telemetry comes in. Stay tuned for more! - Avneet (Azure IoT Central team) – avneet723 Apr 23 '20 at 19:13