A cron-like scheduler with sane DSL
(job "Say 'Hi' all the time" every 5.seconds (print "Hi"))
(job "Compose and send monthly report"
every 1.month (send-report (compose-monthly-report)))
If you want to see it with your eyes, make sure to load the following code:
(defun write-to-file (msg file)
(with-open-file (log file
:direction :output
:if-exists :append
:if-does-not-exist :create)
(format log "~A~%" msg)))
(job "Print farbe" every 3.seconds (write-to-file "Farbe" "log.txt"))
(job "Print colour" every 2.seconds (write-to-file "Colour" "log.txt"))
(job "Print @@@@ 1 min @@@@@" every 1.minute
(write-to-file "@@@@@@ 1 min @@@@@@" "log.txt"))
Now, after (clerk:start), tailing log.txt should give you something like this:
Colour
Farbe
Colour
Colour
Farbe
Colour
Farbe
Colour
Colour
Farbe
Colour
/one minute later.../
@@@@@@ 1 min @@@@@@
/etc.../
The original idea was for users to use the library to execute some sort of execution of a configuration file. However you can use the job creation process programatically with the underlying function job-fn. E.g.:
(defparameter *query-interval* 5)
(job-fn (format nil "Query the API every ~A seconds" *query-interval*)
'every
`(,*query-interval* seconds)
#'query-api-fn)
As you can see, you have to provide a function (either anonimous function or a function symbol) as the last argument.
Clone the repo inside quicklisp/local-projects and do (ql:quicklisp :clerk) in your REPL.
Make sure your jobs are loaded before executing (clerk:start). The jobs reside inside clerk:*jobs*, but you can also type (clerk:calendar) to see a list of all scheduled and running jobs.
There are two types of jobs - continuous and one-time. If a job has the keyword every after the job description - the job will be countinuous. This means that when an event is fired, a new event will be pushed in the event queue for firing exactly interval time from now. The jobs above are an example for continuous jobs.
A one-time job is fired once and then it is removed from the jobs' queue. An example for a one-time job can be:
(job "Extraordinary event" in 5.days (send-mail "Don't forget X"))
You can use any word instead of in.
Right now (more are coming soon) there are 2 type of intervals:
- Numbered intervals
[number].[interval-type]
where the number is a positive integer and the interval-type if one of the following: second, minute, hour, day, week, month, year. Also you can use the plural form of all these words. For example 1.second and 2.seconds are both valid.
- Days of the week
(job "Weekly report" every monday (create-report))
Pretty self-explanatory. The idea is that if you type the day of the week, clerk will calculate when it is and add an event to the queue.
If you have issues - open a github issue or contact me at (reverse "moc.liamg@vokist"). If you want to contribute - open an issue or make a PR. Thanks!