基于 Nginx+lua+Memcache 實現灰度發布
一、灰度發布原理說明
執行過程：
當用戶請求到達前端代理服務Nginx，內嵌的lua模塊解析Nginx配置文件中的lua腳本代碼；
Lua變量獲得客戶端IP地址，去查詢memcached緩存內是否有該鍵值，如果有返回值執行@client_test，否則執行@client。
Location @client_test把請求轉發給部署了new版代碼的服務器，location @client把請求轉發給部署了normal版代碼的服務器，服務器返回結果。整個過程完成。
下面把安裝配置過程詳細說明。
二、安裝配置過程詳解
1、安裝nginx
安裝依賴包
yum -y install gcc gcc-c++ autoconf libjpeg libjpeg-devel libpng libpng-devel freetype freetype-devel libxml2 libxml2-devel zlib zlib-devel glibc glibc-devel glib2 glib2-devel bzip2 bzip2-devel ncurses ncurses-devel curl curl-devel e2fsprogs e2fsprogs-devel krb5 krb5-devel libidn libidn-devel openssl openssl-devel openldap openldap-devel nss_ldap openldap-clients openldap-servers make pcre-devel
yum -y install gd gd2 gd-devel gd2-devel lua lua-devel
yum –y install memcached
下載lua模塊、lua-memcache操作庫文件和nginx包
wget https://github.com/simpl/ngx_devel_kit/archive/v0.2.18.tar.gz
wget https://github.com/chaoslawful/lua-nginx-module/archive/v0.8.5.tar.gz
wget https://github.com/agentzh/lua-resty-memcached/archive/v0.11.tar.gz
wget http://nginx.org/download/nginx-1.4.2.tar.gz
#解壓編譯安裝
tar xvf nginx-1.4.2.tar.gz
cd nginx-1.4.2/
./configure
--prefix=/soft/nginx/
--with-http_gzip_static_module
--add-module=/root/ngx_devel_kit-0.2.18/
--add-module=/root/lua-nginx-module-0.8.5/
make&&make install
拷貝lua的memcached操作庫文件
tar xvf v0.11.tar.gz
cp -r lua-resty-memcached-0.11/lib/resty/ /usr/lib64/lua/5.1/
配置nginx
#vim /soft/nginx/conf/nginx.conf
worker_processes 1;
events {
worker_connections 1024;
}
http {
include mime.types;
default_type application/octet-stream;
sendfile on;
keepalive_timeout 65;
proxy_next_upstream error timeout;
proxy_redirect off;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $http_x_forwarded_for;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
client_max_body_size 100m;
client_body_buffer_size 256k;
proxy_connect_timeout 180;
proxy_send_timeout 180;
proxy_read_timeout 180;
proxy_buffer_size 8k;
proxy_buffers 8 64k;
proxy_busy_buffers_size 128k;
proxy_temp_file_write_size 128k;
upstream client {
server 192.168.200.29:80;
}
upstream client_test {
server 192.168.200.29:81;
}
server {
listen 80;
server_name localhost;
location / {
content_by_lua '
clientIP = ngx.req.get_headers()["X-Real-IP"]
if clientIP == nil then
clientIP = ngx.req.get_headers()["x_forwarded_for"]
end
if clientIP == nil then
clientIP = ngx.var.remote_addr
end
local memcached = require "resty.memcached"
local memc, err = memcached:new()
if not memc then
ngx.say("failed to instantiate memc: ", err)
return
end
local ok, err = memc:connect("127.0.0.1", 11211)
if not ok then
ngx.say("failed to connect: ", err)
return
end
local res, flags, err = memc:get(clientIP)
if err then
ngx.say("failed to get clientIP ", err)
return
end
if res == "1" then
ngx.exec("@client_test")
return
end
ngx.exec("@client")
';
}
location @client{
proxy_pass http://client;
}
location @client_test{
proxy_pass http://client_test;
}
location /hello {
default_type 'text/plain';
content_by_lua 'ngx.say("hello, lua")';
}
location = /50x.html {
root html;
}
}
}
檢測配置文件。
#/soft/nginx/sbin/nginx -t
nginx: the configuration file /soft/nginx/conf/nginx.conf syntax is ok
nginx: configuration file /soft/nginx/conf/nginx.conf test is successful
啟動nginx
/soft/nginx/sbin/nginx
啟動memcached服務
memcached -u nobody -m 1024 -c 2048 -p 11211 –d
三、測試驗證
telnet localhost 11211
Trying ::1...
Connected to localhost.
Escape character is '^]'.
set 192.168.68.211 0 3600 1
1
STORED
get 192.168.68.211
VALUE 192.168.68.211 9 1
1
END
quit
