SimpleAzureScheduler

A simple standalone scheduler library relying on Azure Table Storage.

Currently this is a prototype, a pre-alpha version that still needs to be tested. To be used at your own risk.

##Design goals

• Optimize Storage transactions as much as possible. This is done using RangeQueries and BatchOperations only, grouping transactions as much as possible. Scheduling and Fetching 50 tasks can be done with 3 transactions only.
• Simple and non intrusive API
• Scheduler class has to be thread safe (and should already be)

##How to use it

• Take a look at the code snippet in the unit test project

• The Scheduler class expect to get a storage connection string from the ConfigurationManager, using the key "StorageConnectionString"

• Before compiling don't forget to add "Azure Storage" package from nuget

    	using (Scheduler scheduler = new Scheduler())
        {
  
            for (int i = 0; i < 100; i++)
            {
                
                TimeSpan ts = TimeSpan.FromSeconds(random.Next(10)); // timespan in the next 10 seconds
                object taskData = new { Title = string.Format("Do it in {0} seconds", ts.TotalSeconds) }; //task data object can be anything System.Helper.Json can handle
    			
    			
    			//How to schedule a task:
                scheduler.ScheduleTask(Tasks.Todo, ts, taskData); //thread safe
            }
  
  
            IDisposable trigger = Execute.AtInterval(TimeSpan.FromSeconds(1), x => //execute every second
            {
                //how to retrive tasks
                foreach (ScheduledTask task in scheduler.FetchScheduledItems(Tasks.Todo))
                {
                    dynamic data = task.GetData(); // there's also a generic version: T GetData<T>()
                    string title = data.Title.ToString();
  
                    Trace.WriteLine(string.Format("{2} - Processed task {0} - Category: {1} ", task.Id, title, DateTime.Now.ToLongTimeString()));
  
                    scheduler.Close(task); //close the task (otherwise it will be executed again later)
                }
            });
  
            Thread.Sleep(10000); //wait to let the timer execute incomming tasks
  
            trigger.Dispose(); //stops executing
  
        }//the scheduler must be always disposed to makes sure everything was saved