diff --git a/index.js b/index.js
index 739f600..af5cb70 100644
--- a/index.js
+++ b/index.js
@@ -9,56 +9,61 @@ import { uuid, sha1 } from 'crypto.js'
 import RedisStore from './lib/redis-store.js'
 
 // 会话安装包
-export const sessionPackage = {
-  name: 'session',
-  install() {
-    var session = this.get('session')
-    // 这里只创建session的存储器, 而初始化操作在中间件中进行
-    return new RedisStore(session)
+export function createSessionPlugin(){
+
+  return {
+    name: 'session',
+    install() {
+      var session = this.get('session')
+      // 这里只创建session的存储器, 而初始化操作在中间件中进行
+      return new RedisStore(session)
+    }
   }
 }
 
 // 会话中间件
-export function sessionConnect(req, res, next) {
-  var opt = this.get('session')
-  var cache = req.cookie('NODESSID')
-  var deviceID = ''
-  var ssid
-
-  // options请求不处理会话
-  if (req.method === 'OPTIONS') {
-    return next()
-  }
-
-  // 校验UA
-  if (opt.level & 2) {
-    deviceID += req.header('user-agent')
-  }
-
-  // 校验IP
-  if (opt.level & 4) {
-    deviceID += req.ip()
-  }
-
-  if (deviceID) {
-    deviceID = sha1(deviceID)
-
-    // ssid 最后16位是指纹
-    if (cache) {
-      if (cache.slice(-16) === deviceID.slice(-16)) {
-        ssid = cache
-      } else {
-        ssid = uuid('') + deviceID.slice(-16)
-      }
+export function createSession(){
+  return function (req, res, next) {
+    var opt = this.get('session')
+    var cache = req.cookie('NODESSID')
+    var deviceID = ''
+    var ssid
+  
+    // options请求不处理会话
+    if (req.method === 'OPTIONS') {
+      return next()
     }
-  } else {
-    ssid = cache || sha1(uuid())
+  
+    // 校验UA
+    if (opt.level & 2) {
+      deviceID += req.header('user-agent')
+    }
+  
+    // 校验IP
+    if (opt.level & 4) {
+      deviceID += req.ip()
+    }
+  
+    if (deviceID) {
+      deviceID = sha1(deviceID)
+  
+      // ssid 最后16位是指纹
+      if (cache) {
+        if (cache.slice(-16) === deviceID.slice(-16)) {
+          ssid = cache
+        } else {
+          ssid = uuid('') + deviceID.slice(-16)
+        }
+      }
+    } else {
+      ssid = cache || sha1(uuid())
+    }
+  
+    res.cookie('NODESSID', ssid, { maxAge: opt.ttl, domain: opt.domain })
+    // 缓存ssid到req上
+    req.ssid = ssid
+    this.$$session.update(ssid)
+  
+    next()
   }
-
-  res.cookie('NODESSID', ssid, { maxAge: opt.ttl, domain: opt.domain })
-  // 缓存ssid到req上
-  req.ssid = ssid
-  this.$$session.start(ssid)
-
-  next()
 }
diff --git a/lib/redis-store.js b/lib/redis-store.js
index 68d6287..66c14ca 100644
--- a/lib/redis-store.js
+++ b/lib/redis-store.js
@@ -7,25 +7,29 @@
 import Ioredis from 'ioredis'
 
 export default class Session {
+
+  #store = null
+  #ttl = 60
+
   constructor(opt) {
-    this.store = new Ioredis({
+    this.#store = new Ioredis({
       host: opt.db.host || '127.0.0.1',
       port: opt.db.port || 6379,
       db: opt.db.db || 0
     })
-    this.ttl = opt.ttl
+    this.#ttl = opt.ttl
   }
 
-  start(ssid) {
+  update(ssid) {
     // 设置session有效期
-    this.store.expire(ssid, this.ttl)
+    this.#store.expire(ssid, this.#ttl)
   }
 
   // 获取session字段值, 需要await指令
   get(ssid, key) {
     var defer = Promise.defer()
 
-    this.store.hgetall(ssid, (err, obj) => {
+    this.#store.hgetall(ssid, (err, obj) => {
       if (err) {
         return defer.reject(err)
       }
@@ -37,7 +41,7 @@ export default class Session {
       }
       //不传key时,直接返回全部字段
       if (key) {
-        defer.resolve(obj.hasOwnProperty(key) ? obj[key] : null)
+        defer.resolve(obj[key])
       } else {
         defer.resolve(obj)
       }
@@ -49,20 +53,20 @@ export default class Session {
   set(ssid, key, val) {
     if (typeof key === 'object') {
       for (let i in key) {
-        this.store.hset(ssid, i, key[i])
+        this.#store.hset(ssid, i, key[i])
       }
     } else {
-      this.store.hset(ssid, key, val)
+      this.#store.hset(ssid, key, val)
     }
   }
 
   //删除单个字段
   unset(ssid, key) {
-    this.store.hdel(ssid, key)
+    this.#store.hdel(ssid, key)
   }
 
   //清除个人session
   clear(ssid) {
-    this.store.del(ssid)
+    this.#store.del(ssid)
   }
 }