cron-swift
A sample CLI tool for cron scheduling.
Coding Test
We have a set of tasks, each running at least daily, which are scheduled with a simplified cron. We want to find when each of them will next run.
The scheduler config looks like this:
30 1 /bin/run_me_daily
45 * /bin/run_me_hourly
* * /bin/run_me_every_minute
* 19 /bin/run_me_sixty_times
The first field is the minutes past the hour, the second field is the hour of the day and the third is the command to run. For both cases * means that it should run for all values of that field. In the above example run_me_daily has been set to run at 1:30am every day and run_me_hourly at 45 minutes past the hour every hour. The fields are whitespace separated and each entry is on a separate line.
We want you to write a command line program that when fed this config to stdin and the simulated 'current time' in the format HH:MM as command line argument outputs the soonest time at which each of the commands will fire and whether it is today or tomorrow.
When the task should fire at the simulated 'current time' then that is the time you should output, not the next one.
For example given the above examples as input and the simulated 'current time' command-line argument 16:10 the output should be
1:30 tomorrow - /bin/run_me_daily
16:45 today - /bin/run_me_hourly
16:10 today - /bin/run_me_every_minute
19:00 today - /bin/run_me_sixty_times
How to install the tool
swift build --configuration release
cp -f .build/release/CronSwift /usr/local/bin/CronSwift
How to run the command
cat input.txt | cronswift 16:10