lua 日期的一些函数

--根据日期获取星期几
function getWeekNum(strDate)
    local ymd = Split(strDate,"-")
    t = os.time({year=tostring(ymd[1]),month=tostring(ymd[2]),day=tostring(ymd[3])})
    local weekNum = os.date("*t",t).wday  -1
    if weekNum == 0 then
        weekNum = 7
    end
    return weekNum
end

ngx.say(getWeekNum("2018-04-25"))

--根据一个日期获取下几天，dayChange参数为下几天
function getNextDay(strDate,dayChange)
    local _startDate = Split(startDate,"-")    
    local time=os.time({year=tostring(_startDate[1]), month=tostring(_startDate[2]), day=tostring(_startDate[3])})+dayChange*86400 --一天86400秒
    return (os.date('%Y',time).."-"..os.date('%m',time).."-"..os.date('%d',time))    
end

ngx.say(getNextDay("2018-04-25", 1))

--计算一个时间段中有几天
function getDays(startDate, endDate)
    local startDateTab = Split(startDate,"-")
    local endDateTab = Split(endDate,"-")    
    numDay1 = os.time({year=tostring(startDateTab[1]), month=tostring(startDateTab[2]), day=tostring(startDateTab[3])})
    numDay2 = os.time({year=tostring(endDateTab[1]), month=tostring(endDateTab[2]), day=tostring(endDateTab[3])})    
    return (numDay1-numDay2)/(3600*24)+1;
end

ngx.say(getDays("2018-04-25", "2018-04-20"))

--遍历一个值是否在数组中
function IsInTable(value, tbl)
        for k,v in ipairs(tbl) do
                if v == value then
                        return true;
                end
        end
        return false;
end

--获取前10分钟
ngx.print(os.date("%Y%m%d%H%M%S",os.time()-600))