Take a look at kue, which can use Redis-backed queues for periodic tasks,
and cron.js, which allows you to use cron's "beloved" patterns for
specifying when / how often tasks are run.

F

On Sunday, December 16, 2012, Brian Link wrote:

> Could be done in redis also, with a sorted set, where the values are json
> payloads of task data and the scores are timestamps.  On an interval (like
> Jonathan suggested) you could do a query for all items older than 'now' and
> start processing them.
>
> On Sunday, December 16, 2012 12:12:11 PM UTC-8, Jonathan Dickinson wrote:
>>
>> If you care about failure resilience at all:
>>
>> 1. You will need a pseudoqueue in SQL (or whatever) with a datetime field
>> indicating when the event needs to fire.
>> 2. Every, say, 5 minutes (settimeout) query SQL for anything that needs
>> to happen in the next, say, 6 minutes.
>> 3. Calculate the difference between now and when the event needs to occur
>> and settimeout.
>> *** If you get anything that needed to happen in the past execute it
>> immediately.
>>
>> If your server is clustered you will also need a way to mark a row as
>> "server <ID> is dealing with this", "this has been dealt with" (which is
>> soon followed by deleting the row). You cluster will also need to be aware
>> of failing servers so that you can pick up the work they started but did
>> not finish. Your updates have to be atomic (e.g. 'UPDATE [Queue] SET
>> [ServerID] = @ThisServer WHERE [ServerID] IS NULL AND [ID] = @RowID').
>>
>> This type of pseudoqueue isn't *that* hard to write, you just need to
>> think about it a bit.
>>
>> On Sunday, 16 December 2012 15:53:40 UTC+2, Filipe wrote:
>>>
>>> Guys, simple question, but I can't find a way to do this: schedule
>>> date/time events.
>>>
>>> For example: get dynamically an event from a database (ie 12:00
>>> 01/01/2013 - "first lunch of 2013") and push it to my users only when local
>>> time is exactly 12:00 01/01/2013.
>>>
>>> What's the clever way to do this?
>>>
>>>  --
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