nginx+lua+redis 灰度发布实现方案

//外部配置
include lua.conf;
//新系统地址
upstream new{
      server 192.168.1.103:8081;
}
//老系统地址
upstream old{
      server 192.168.1.103:8080;
}

//引入redis模块，只能联单机
local redis = require "resty.redis"
local cache = redis.new()
cache:set_timeout(60000)
//链接
local ok, err = cache.connect(cache, '192.168.19.10', 6379)
// 这里如果链接redis失败，则转发到@old对应的服务器 (传统服务)
if not ok then
    ngx.exec("@old")
    return
end

//如果nginx只有一层分发层，这下面四行代码可以不写
local local_ip = ngx.req.get_headers()["X-Real-IP"]
if local_ip == nil then
    local_ip  = ngx.req.get_headers()["x_forwarded_for"]
end

//从remote_addr变量中拿到客户端ip，同样nginx只有一层的时候此变量为客户端ip，多层不是
if local_ip == nil then
    local_ip = ngx.var.remote_addr
end

//在redis中根据客户端ip获取是否存在值; redis中存放的是key:ip val:ip, 存放的ip访问微服务
local intercept = cache:get(local_ip)
//如果存在则转发到@new对应的服务器(微服务)
if intercept == local_ip then
    ngx.exec("@new")
    return
end
//如果不存在，则转发到@old对应的服务器(传统服务)
ngx.exec("@old")
//关闭客户端
local ok, err = cache.close()
if not ok then
    ngx.say("failed to close:", err)
    return
end

//这里缓存服务地址
backend = "http://192.168.1.156:8080"
//缓存服务访问路径
local method = "httptest"
local requestBody = "/"..method
//模块
local http = require("resty.http")
local httpc = http.new()
//设置超时时间
httpc:set_timeout(1000)
//发送请求
local resp, err = httpc:request_uri(backend, {--
    method = "GET", --
    path = requestBody,
    keepalive = false
})
//如果请求失败访问老系统
if not resp then--
    ngx.exec("@old")----
    return--
end
//缓存服务取回ip
local isHave = resp.body
//关闭连接
httpc:close()
//请求ip
local local_ip = ngx.var.remote_addr
//命中则访问微服务
if isHave == local_ip then
    ngx.exec("@new")
    return
end
//没命中访问老系统
ngx.exec("@old")

backend = "http://192.168.1.156:8080"
//加载共享内存
local cache_ngx = ngx.shared.rediscache
local local_ip = ngx.var.remote_addr
//优先从本地缓存中去取
local cacheip = cache_ngx:get(local_ip)
//本地缓存中不存在，去缓存服务中去取，然后加载到本地缓存
if cacheip == "" or cacheip == nil then
    local http = require("resty.http")
    local httpc = http.new()
    httpc:set_timeout(1000)
    local method = "httptest"
    local requestBody = "/" .. method
    local resp, err = httpc:request_uri(backend, {
        method = "GET",
        path = requestBody,
        keepalive=false
    })
    if not resp then
        ngx.exec("@new")
        return
    end
    cacheip = resp.body
    httpc:close()
    //加载到本地缓存，设置过期时间
    cache_ngx:set(local_ip, cacheip, 10*60)
end
if cacheip == local_ip then
    ngx.exec("@new")
    return
end
ngx.exec("@old")