Lua获取系统时间和时间格式化方法及格式化参数

一、系统当前时间对应的时间戳

local ntime = os.time
print(ntime)

二、格式化时间显示，参考下表
常用于设置header等

ngx.header["last-modified:"]  = os.date("%a, %d %b %y %x gmt")
ngx.header["content-type"]    = "text/html; charset=utf-8"
ngx.header["cache-control"]   = "public"
ngx.header["expires"]         = os.date("%a, %d %b %y %x gmt", os.time() + cdncachetime)

%a	abbreviated weekday name (e.g., wed)
%a	full weekday name (e.g., wednesday)
%b	abbreviated month name (e.g., sep)
%b	full month name (e.g., september)
%c	date and time (e.g., 09/16/98 23:48:10)
%d	day of the month (16) [01-31]
%h	hour, using a 24-hour clock (23) [00-23]
%i	hour, using a 12-hour clock (11) [01-12]
%m	minute (48) [00-59]
%m	month (09) [01-12]
%p	either "am" or "pm" (pm)
%s	second (10) [00-61]
%w	weekday (3) [0-6 = sunday-saturday]
%x	date (e.g., 09/16/98)
%x	time (e.g., 23:48:10)
%y	full year (1998)
%y	two-digit year (98) [00-99]
%%	the character '%'