ColdFusion - complete next scheduled task due to launch

Question

This thread was useful for figuring out the next execution time for a scheduled task.

How do I know the next runtime for a scheduled task?

But is there a way to just complete the next scheduled task due to a launch?

If I can get the date and name of the next task due to start, I can connect this date to the jQuery countdown timer, which will display the countdown to the next scheduled task, for example:

TaskABC due to run in: 12 03 20 hrs min sec 

. This is for admin interface if you are wondering how geeky can get :-)

EDIT

Answer 1

I had the same thought as Bill. But it was curious if there was another way.

I poked and apparently the internal Scheduler class maintains a list of upcoming tasks. The list is private, but you can use the same reflection technique to access it. Interestingly, the list also includes system tasks, such as message queue manager, session / application trackers, observers, etecetera. So you have to go through it until you find the "scheduled task", that is, CronTabEntry

Below is a very poorly tested feature that seems to do the trick in CF9. (Note: Enables the CreateTimeStruct function from http://www.cflib.org ).

Rules:

• Returns a structure containing the name and time remaining until the next task. If no tasks are found, result.task is an empty string.
• Excludes suspended tasks

Application:

 result = new TaskUtil().getNextTask(); WriteDump(result); 

Cfc

 component { public struct function getNextTask() { // get list of upcoming tasks from factory (UNDOCUMENTED) local.scheduler = createObject("java", "coldfusion.server.ServiceFactory").getSchedulerService(); local.taskField = local.scheduler.getClass().getDeclaredField("_tasks"); local.taskField.setAccessible( true ); local.taskList = local.taskField.get(local.scheduler); // taskList contains system jobs too, so we must iterate // through the tasks to find the next "scheduled task" local.nextTask = ""; local.tasks = local.taskList.iterator(); while ( local.tasks.hasNext() ) { local.currTask = local.tasks.next(); local.className = local.currTask.getRunnable().getClass().name; // exit as soon as we find a scheduled task that is NOT paused if (local.className eq "coldfusion.scheduling.CronTabEntry" && !local.currTask.getRunnable().paused) { local.nextTask = local.currTask; break; } } // if we found a task, calculate how many days, hours, etcetera // until its next run time local.details = { task="", remaining={} }; if ( isObject(local.nextTask) ) { local.secondsToGo = (local.nextTask.getWhen() - now().getTime()) / 1000; local.details.task = local.nextTask.getRunnable().task; local.details.remaining = createTimeStruct(local.secondsToGo); local.details.nextDate = dateAdd("s", local.nextTask.getWhen() / 1000 , "January 1 1970 00:00:00" ); } return local.details; } /** * Abbreviated version of CreateTimeStruct by Dave Pomerance * See http://www.cflib.org/index.cfm?event=page.udfbyid&udfid=421 * * @param timespan The timespan to convert. * @return Returns a structure. * @author Dave Pomerance * @version 1, January 7, 2002 */ public struct function CreateTimeStruct(required numeric timespan) { var timestruct = StructNew(); var mask = "s"; // only 4 allowed values for mask - if not one of those, return blank struct if (ListFind("d,h,m,s", mask)) { // compute seconds if (mask eq "s") { timestruct.s = (timespan mod 60) + (timespan - Int(timespan)); timespan = int(timespan/60); mask = "m"; } else timestruct.s = 0; // compute minutes if (mask eq "m") { timestruct.m = timespan mod 60; timespan = int(timespan/60); mask = "h"; } else timestruct.m = 0; // compute hours, days if (mask eq "h") { timestruct.h = timespan mod 24; timestruct.d = int(timespan/24); } else { timestruct.h = 0; timestruct.d = timespan; } } return timestruct; } } 

Answer 2

My first thought is to repeat the Leigh getNextRunTime(string taskName) over a set of tasks. You can get an array of structures containing the details of all scheduled tasks using taskArray = createobject("java","coldfusion.server.ServiceFactory").getCronService().listAll();

The key in the structure containing the task name is the "task". Thus, you can extract all the task names as an array, for example, run the Leigh function for each element and determine which one will work next.