lua-resty-gearman模块

粘贴一段百度对gearman的解释：

Gearman是一个用来把工作委派给其他机器、分布式的调用更适合做某项工作的机器、并发的做某项工作在多个调用间做负载均衡、或用来在调用其它语言的函数的系统。

lua-resty-gearman模块用于在lua中调用gearman

github地址   https://github.com/zhhchen/lua-resty-gearman

调用的代码样例：

lua_package_path "/path/to/lua-resty-gearman/lib/?.lua;;";

server {
    location /test {
        content_by_lua '
            local gearman = require "resty.gearman"
            local gm = gearman:new()

            gm:set_timeout(1000) -- 1 sec

            local ok, err = gm:connect("127.0.0.1", 4730)
            if not ok then
                ngx.say("failed to connect: ", err)
                return
            end

            ok, err = gm:submit_job("wc", "11111
22222
33333")  
            -- submit_job,submit_job_bg,submit_job_high,submit_job_high_bg,submit_job_low,submit_job_low_bg are supported
            -- submit_job(function_name, workload[, unique])
            
            if not ok then
                ngx.say("failed to submit job: ", err)
                return
            else
                ngx.say(ok)                
            end

            -- put it into the connection pool of size 100,
            -- with 0 idle timeout
            local ok, err = gm:set_keepalive(0, 100)
            if not ok then
                ngx.say("failed to set keepalive: ", err)
                return
            end

            -- or just close the connection right away:
            -- local ok, err = gm:close()
            -- if not ok then
            --     ngx.say("failed to close: ", err)
            --     return
            -- end
        ';
    }
}

gearman提交工作时有多种方式：

submit_job为普通的工作任务，client得到状态更新及通知任务已经完成的响应；

submit_job_bg为异步的工作任务，client不关心任务的完成情况；

submit_job_high为高优先级的工作任务；

submit_job_high_bg为高优先级的异步任务；

submit_job_low为低优先级的工作任务；

submit_job_low_bg为低优先级的异步任务。