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Scheduled Backend Tasks - Windows Azure Mobile Services

Using Windows Azure Mobile Services we can create in a short period of time a simple backend for our application. In the last period of time a great feature appeared – Scheduled Backend Tasks
This feature permit users to create jobs that can run at a specific time interval. Imagine that you have an application that track the GPS location of users for the last 6 hours. All the information those are older than 6 hours can be removed. This problem could be solved by a manual trigger, but we are the XXI century, everything needs to be automatized. In this case you would have a job on a server that would make this cleanup. But wait; way would you need something like this when Mobile Services give you the possibility to create your backed very easily.
The scheduled job support gives us the possibility to create a job that run at specific time intervals or demand. Each job that is created can be enabling or disable anytime. Also, jobs can be run manually, using the “RUN ONCE” functionality. 
The language that can be used to define each job is JavaScript. It is the same language used to define custom scripts over tables from Mobile Services. From this job we can execute any kind of code over tables from Mobile Services or we can call remote services. You can imagine any kind of scenarios. The script need to added from the Windows Azure Portal, in this moment there is no support to define it in Visual Studio and make a deploy.
I tried to find what are the current limitation (January 2013) of Scheduled Backed Tasks. What I found until now is:
  • The smallest time interval is 15 minutes
  • Modules supported in this moment are: “azure”, “sendgrid”, “request” (but this list will expand)
  • There is no maxim time limit and you don’t pay for computation time. BUT (yes, there is a but), if you run scripts that drain the CPU that the task will be terminated
Don’t forget that scheduled backend task can be used with success when we want to use push notifications at a time interval. Another case when you can use this feature is to test custom scripts that are defined over tables from Mobile Services.


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