这篇文章主要介绍了如何在OpenResty中配置和使用定时任务。首先，文章解释了定时任务需要与worker绑定，通常默认绑定到worker_id=0，这样在Nginx进程中只执行一个timer。然后，文章提供了在nginx.conf中配置定时任务的具体方法。接着，文章介绍了如何使用ngx.timer.every接口，这是ngx提供的最新接口。最后，文章提供了一些相关的日志输出和错误处理方法。
openresty的定时任务是要跟worker绑定的。如果不绑定特定的worker，那么所有启动的woker都会去执行定时任务。
一般情况下默认绑定worker_id=0的，这样在nginx整个进程里面，就只执行一个timer。
在conf中具体的位置可以写自己的任务逻辑。
具体的nginx.conf配置如下：
worker_processes 1;
error_log logs/error.log;
events {
worker_connections 1024;
}
http {
init_worker_by_lua_block {
local delay = 2 -- in seconds
local new_timer = ngx.timer.at
local log = ngx.log
local ERR = ngx.ERR
local check
check = function(premature)
if not premature then
-- do the health check or other routine work
log(ERR, "mm test mm test")
local ok, err = new_timer(delay, check)
if not ok then
log(ERR, "failed to create timer: ", err)
return
end
end
end
if 0 == ngx.worker.id() then
local ok, err = new_timer(delay, check)
if not ok then
log(ERR, "failed to create timer: ", err)
return
end
end
}
server {
listen 8081;
location / {
default_type text/html;
content_by_lua '
ngx.say("<p>hello, world</p>")
';
}
location = /app/test {
content_by_lua_block {
local res = ngx.location.capture(
"/sum", {args={a=3, b=8}}
)
ngx.say("status:", res.status, " response:", res.body)
}
}
location = /sum {
internal;
content_by_lua_block {
ngx.sleep(0.1)
local args = ngx.req.get_uri_args()
ngx.print(tonumber(args.a) + tonumber(args.b))
}
}
location = /subduction {
internal;
content_by_lua_block {
ngx.sleep(0.1)
local args = ngx.req.get_uri_args()
ngx.print(tonumber(args.a) - tonumber(args.b))
}
}
location = /app/test_parallels {
content_by_lua_block {
local start_time = ngx.now()
local res1, res2 = ngx.location.capture_multi( {
{"/sum", {args={a=3, b=8}}},
{"/subduction", {args={a=3, b=8}}}
})
ngx.say("status:", res1.status, " response:", res1.body)
ngx.say("status:", res2.status, " response:", res2.body)
ngx.say("time used:", ngx.now() - start_time)
}
}
location = /app/test_queue {
content_by_lua_block {
local start_time = ngx.now()
local res1 = ngx.location.capture_multi( {
{"/sum", {args={a=3, b=8}}}
})
local res2 = ngx.location.capture_multi( {
{"/subduction", {args={a=3, b=8}}}
})
ngx.say("status:", res1.status, " response:", res1.body)
ngx.say("status:", res2.status, " response:", res2.body)
ngx.say("time used:", ngx.now() - start_time)
}
}
}
}
注意init_worker_by_lua_block是放在http里面的。因为此处只配置了error.log，因此是打印的err级别的日志，方便观察。
接下来启动ngin：sudo nginx -p pwd/ -c conf/nginx.conf
然后tailf logs/error.log:
追日志会发现，每隔2s就会打印一条日志。
二、使用ngx.timer.every接口
ngx提供了最新的ngx.timer.every接口，再来试一下：
init_worker_by_lua_block {
local delay = 2 -- in seconds
-- local new_timer = ngx.timer.at
local log = ngx.log
local ERR = ngx.ERR
local check
check = function(premature)
if not premature then
-- do the health check or other routine work
log(ERR, "mm test mm test")
-- local ok, err = new_timer(delay, check)
-- if not ok then
-- log(ERR, "failed to create timer: ", err)
-- return
-- end
end
end
if 0 == ngx.worker.id() then
local ok, err = ngx.timer.every(delay, check)
if not ok then
log(ERR, "failed to create timer: ", err)
return
end
end
}
