scheduling_dsl_idea.js

scheduling_dsl_idea.js

/*
# ┌───────────── start minute (0 - 59)
# │ ┌───────────── start hour (0 - 23)
# │ │ ┌──────────── end minute (0 - 59)
# │ │ │ ┌───────────── end hour (0 - 23)
# │ │ │ │ ┌───────────── day of the month (1 - 31)
# │ │ │ │ │ ┌───────────── month (1 - 12)
# │ │ │ │ │ │ ┌───────────── day of the week (0 - 6) (Sunday to Saturday)
# │ │ │ │ │ │ │
# │ │ │ │ │ │ │
# * * * * * * * <command to execute>

 */

const testDsl = [
    // createDsl(11, 6, 2, 22, 3, 33),
    // createDsl(11, 6, 3, 22, 3, 33),
    // createDsl("*", 6, 3, 22, 3, 33), // every month
    // createDsl(11, "*", 3, 22, 3, 33), // every day
    createDsl(11, "*", 3, 22, 3, 33, "0,4"), // only on Mon and Fri
]

function createDsl(month, dayOfMonth, startHour, startMinute, endHour, endMinute, dayOfWeek) {
    return `${startMinute} ${startHour} ${endMinute} ${endHour}` +
        ` ${dayOfMonth} ${month} ${dayOfWeek === undefined ? "*" : dayOfWeek}`
}

function *getRange(dsl, startDate, endDate) {
    const parts = dsl.split(" ");
    const startYear = startDate.getFullYear()
    const endYear = endDate.getFullYear()
    const monthParam = parts[5]
    const dayOfMonthParam = parts[4]
    const dayOfWeekParam = parts[6]
    const processDays = function*(year, month, day) {
        const dayOfWeek = new Date(year, month, day).getDay()
        const selectedDays = dayOfWeekParam === "*" ? [] : dayOfWeekParam
            .split(",")
            .map(d => parseInt(d.trim()))
            .filter(d => !isNaN(d))

        if (selectedDays.length === 0 || selectedDays.find(d => d === dayOfWeek)) {
            const startTime = new Date(year, month, day, parseInt(parts[1]) + 1, parseInt(parts[0]))
            const endTime = new Date(year, month, day, parseInt(parts[3]) + 1, parseInt(parts[2]))
            yield [startTime, endTime]
        }
    }

    const processMonths = function*(year, month)  {
        if (dayOfMonthParam === "*") {
            const daysInMonth = new Date(year, month, 0).getDate()
            for (let day = 1; day < daysInMonth; day ++) {
                yield* processDays(year, month, day)
            }
        } else {
            yield* processDays(year, month, parseInt(dayOfMonthParam))
        }
    }

    for (let year = startYear; year <= endYear; year ++) {
        if (monthParam === "*") {
            for (let month = 0; month < 12; month ++) {
                yield* processMonths(year, month)
            }
        } else {
            yield* processMonths(year, parseInt(monthParam) - 1)
        }
    }
}

for (let dsl of testDsl) {
    console.log(dsl)
    for (let range of getRange(dsl, new Date(2001, 1, 1), new Date(2001, 1, 1))) {
        console.log(range)
    }
}