How to handle limited operands for windows azure service?

Question

I am using windows azure notification hub, and i got this message:

Tag expression can not contain more than 6 operands

So it restricted me to only 6 tags per request , and I need to send to more than 6 tags .

What can I do?

Answer 1

Tag expression was designed for audience targeting purposes. Let's consider simple example:

We have food related application, each device creates registration with tags. One tag for city (NY, Washington, Seattle,..) and several tags for preferred foods (steaks, cookies, burgers,..).

Now new bakery is opened in NY and we want to send an advertising to all cookie-lovers in the NY. So we do just one send call using expression "(NY && cookies)" and all those devices will receive the advertising even if there are million of them.

Here is official doc.

Looks like 6 tags per expression can cover most of such scenarios. There is also option to use up to 20 tags for OR-only expression like "(A || B || C ...)"

In your case I would suggest to redefine tags to allow group of devices to be covered with tag or tag expression. It would allow to use broadcast capabilities of the notification hub.

Otherwise if your tag is something unique like userId or email then you will have to perform multiple calls to reach multiple devices. That scenario is OK as well since NH is scalable and high-available service.