ngx_http_dyups_module

Description

This module can be used to update your upstream-list without reloadding Nginx.

  1. TODO:
  3. It can not work with common `nginx_upstream_check_module`.

Compilation

The module is not compiled into Tengine by default. It can be enabled with '—with-http_dyups_module'configuration parameter, and enabled lua support with '—with-http_dyups_lua_api'.But it can not be compiled as a '.so'.

Example

file: conf/nginx.conf

  1. daemon off;
    error_log logs/error.log debug;

    events {
    }

    http {

        dyups_upstream_conf  conf/upstream.conf;

        include conf/upstream.conf;

        server {
            listen   8080;

            location / {
                proxy_pass http://$host;
            }
        }

        server {
            listen 8088;
            location / {
                echo 8088;
            }
        }

        server {
            listen 8089;
            location / {
                echo 8089;
            }
        }

        server {
            listen 8081;
            location / {
                dyups_interface;
            }
        }
    }

file: conf/upstream.conf

  1. upstream host1 {
        server 127.0.0.1:8088;
    }

    upstream host2 {
        server 127.0.0.1:8089;
    }

Directives

Syntax: dyups_interfaceDefault: noneContext: loc

This directive set the interface location where you can add or delete the upstream list. See the section of Interface for detail.

Syntax: dyups_read_msg_timeout timeDefault: 1sContext: main

This directive set the interval of workers readding the commands from share memory.

Syntax: dyups_shm_zone_size sizeDefault: 2MContext: main

This directive set the size of share memory which used to store the commands.

Syntax: dyups_upstream_conf pathDefault: noneContext: main

This directive set the path of file which you dumped all of upstreams' configs, it will be loaded in init process after process respwan to restore upstreams.

Syntax: dyups_trylock on offDefault: offContext: main

You will get a better prefomance but it maybe not stable, and you will get a '409' when the update request conflicts with others.

restful interface

  • /detail get all upstreams and their servers
  • /list get the list of upstreams

  • /upstream/name find the upstream by it's name

  • /upstream/name update one upstream

  • body commands;

  • body server ip:port;

  • /upstream/name delete one upstream

Call the interface, when you get the return code is HTTP_INTERNAL_SERVER_ERROR 500, you need to reload nginx to make the Nginx work at a good state.

If you got HTTP_CONFLICT 409, you need resend the same commands again latter.

The /list and /detail interface will return HTTP_NO_CONTENT 204 when there is no upstream.

Other code means you should modify your commands and call the interface again.

ATTENEION: You also need a third-party to generate the new config and dump it to Nginx'conf directory.

  1. » curl -H "host: dyhost" 127.0.0.1:8080
    <html>
    <head><title>502 Bad Gateway</title></head>
    <body bgcolor="white">
    <center><div class="dh">502 Bad Gateway</div></center>

    * * *
    <center>nginx/1.3.13</center>
    </body>
    </html>

    » curl -d "server 127.0.0.1:8089;server 127.0.0.1:8088;" 127.0.0.1:8081/upstream/dyhost
    success

    » curl -H "host: dyhost" 127.0.0.1:8080
    8089

    » curl -H "host: dyhost" 127.0.0.1:8080
    8088

    » curl 127.0.0.1:8081/detail
    host1
    server 127.0.0.1:8088

    host2
    server 127.0.0.1:8089

    dyhost
    server 127.0.0.1:8089
    server 127.0.0.1:8088

    » curl -i -X DELETE 127.0.0.1:8081/upstream/dyhost
    success

    » curl 127.0.0.1:8081/detail
    host1
    server 127.0.0.1:8088

    host2
    server 127.0.0.1:8089

API

  1. extern ngx_flag_t ngx_http_dyups_api_enable;
    ngx_int_t ngx_dyups_update_upstream(ngx_str_t *name, ngx_buf_t *buf,
        ngx_str_t *rv);
    ngx_int_t ngx_dyups_delete_upstream(ngx_str_t *name, ngx_str_t *rv);

NOTICE:you should add the directive dyups_interface into your config file to active this feature

  1. content_by_lua '
        local dyups = require "ngx.dyups"

        local status, rv = dyups.update("test", [[server 127.0.0.1:8088;]]);
        
        ngx.print(status, rv)
        if status ~= 200 then
            ngx.print(status, rv)
            return
        end
        ngx.print("update success")

        status, rv = dyups.delete("test")
        if status ~= 200 then
            ngx.print(status, rv)
            return
        end
        ngx.print("delete success")

    ';

原文: http://tengine.taobao.org/document_cn/http_dyups_cn.html