Shuttle.Esb.Scheduling 13.0.1

Shuttle.Esb.Scheduling

A simple scheduling solution built on Shuttle.Esb.

See Shuttle.Esb.Scheduling.Server for an example implementation of a scheduler.

Simple Configuration

A schedule has a name for your scheduled job, e.g. ProcessAccounts. You then use a cron expression to indicate when a ScheduleNotification message is published. Any endpoint that is interested in the notification can then subscribe to the ScheduleNotification message and perform the relevant processing.

cron samples

Format is {minute} {hour} {day-of-month} {month} {day-of-week}

{minutes} : 0-59 , - * /
{hours} : 	0-23 , - * /
{day-of-month} 1-31 , - * ? / L W
{month} : 1-12 or JAN-DEC	, - * /
{day-of-week} : 1-7 or SUN-SAT , - * ? / L #

Examples:
* * * * * - is every minute of every hour of every day of every month
5,10-12,17/5 * * * * - minute 5, 10, 11, 12, and every 5th minute after that

How does it fit together?

The basic idea behind the scheduling is that you will have endpoints that already contain the required behaviour. For instance, you may have a PrintInvoices that you can send to an endpoint to perform the processing. You periodically click on a button and this sends off the command. However, you do not want to necessarily send the PrintInvoices from the scheduler as it should not be that tightly coupled to any message.

Instead you can set up how often a named ScheduleNotification is published. In this case it may be the same endpoint that processes the PrintInvoices can subscribe to the ScheduleNotification. It is, therefore, quite conceivable that an endpoint may receive a number of published ScheduleNotification messages, each with a different Name. The handler for this command on the endpoint could use a switch statement to then do a bus.Send to send the relevant actual command to be processed, typically by configuring the message to be sent locally.

By adding this layer of indirection we can have enterprise-grade scheduling that is not at all intrusive and leverages existing functionality.