diff --git a/README.md b/README.md
index 08cb752..0c7dfb7 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,15 @@
 # alioss
 迷你版 Alioss库。 体积虽小, 五脏俱全。
+
+
+## 版本
+> 2个版本, 基础版和完整版。
+
+### 基础版
+
+-  `.auth(path)` 临时对文件签名(用于访问私有文件)
+-  `.policy(dir, size)`  生成policy签名
+-  `.list({prefix, delimiter, max, token})`   列出文件
+-  `.upload(auth, file, path)`   上传文件
+-  `.copy(origin, target)`   复制文件
+-  `.delete(path)`    删除文件
\ No newline at end of file
diff --git a/package.json b/package.json
index e151ae0..bc28b89 100644
--- a/package.json
+++ b/package.json
@@ -1,3 +1,6 @@
 {
-  "name": "@bytedo/alioss"
-}
\ No newline at end of file
+  "name": "@bytedo/alioss",
+  "dependencies": {
+    "crypto.web.js": "^1.0.0"
+  }
+}
diff --git a/src/index.js b/src/index.js
index d9848b5..06efdfc 100644
--- a/src/index.js
+++ b/src/index.js
@@ -4,22 +4,22 @@
  * @date 2020/01/18 14:28:47
  */
 
-import { hmac, base64encode } from 'crypto'
+import { hmac, base64encode } from 'crypto.web.js'
 import xml2js from './lib/xml2js.js'
-import {
-  APP_ID,
-  APP_KEY,
-  MIME_TYPES,
-  DEFAULT_MIME_TYPE
-} from './lib/constants.js'
+import { MIME_TYPES, DEFAULT_MIME_TYPE } from './lib/constants.js'
 import { getMimeType, fixFile, str2sign } from './lib/helper.js'
 
 export default class Alioss {
+  #appid = ''
+  #appkey = ''
+
   #bucket = ''
   #domain = ''
   #api = ''
 
-  constructor(bucket, domain, region) {
+  constructor({ bucket, domain, region, appid, appkey } = {}) {
+    this.#appid = appid
+    this.#appkey = appkey
     this.#bucket = bucket
     this.#domain = domain
     this.#api = `https://${bucket}.${region}.aliyuncs.com`
@@ -32,12 +32,12 @@ export default class Alioss {
     return hmac(
       'SHA-1',
       `GET\n\n\n${time}\n/${this.#bucket}/${key}`,
-      APP_KEY,
+      this.#appkey,
       'base64'
     ).then(signature => {
-      return `?OSSAccessKeyId=${APP_ID}&Expires=${time}&Signature=${encodeURIComponent(
-        signature
-      )}`
+      return `?OSSAccessKeyId=${
+        this.#appid
+      }&Expires=${time}&Signature=${encodeURIComponent(signature)}`
     })
   }
 
@@ -46,7 +46,7 @@ export default class Alioss {
    * dir: 上传目录名
    * size: 大小限制, 单位 MB  默认10MB
    */
-  sign(dir = '', size = 10) {
+  policy(dir = '', size = 10) {
     var time = new Date()
     var params = {
       conditions: [
@@ -61,8 +61,8 @@ export default class Alioss {
 
     policy = JSON.stringify(params)
     policy = btoa(policy)
-    return hmac('SHA-1', policy, APP_KEY, 'base64').then(signature => {
-      return { policy, signature, id: APP_ID }
+    return hmac('SHA-1', policy, this.#appkey, 'base64').then(signature => {
+      return { policy, signature, id: this.#appid }
     })
   }
 
@@ -80,14 +80,14 @@ export default class Alioss {
       `GET\n\n\n${time}\nx-oss-date:${time}\n/${this.#bucket}/${
         token ? '?continuation-token=' + token : ''
       }`,
-      APP_KEY,
+      this.#appkey,
       'base64'
     )
       .then(signature =>
         fetch(this.#api + '?' + query.toParams(), {
           headers: {
             'content-type': void 0,
-            authorization: `OSS ${APP_ID}:${signature}`,
+            authorization: `OSS ${this.#appid}:${signature}`,
             'x-oss-date': time
           }
         })
@@ -137,14 +137,14 @@ export default class Alioss {
         headers,
         key: target
       }),
-      APP_KEY,
+      this.#appkey,
       'base64'
     )
       .then(signature =>
         fetch(`${this.#api}/${target}`, {
           method: 'PUT',
           headers: {
-            authorization: `OSS ${APP_ID}:${signature}`,
+            authorization: `OSS ${this.#appid}:${signature}`,
             ...headers
           }
         })
@@ -158,14 +158,13 @@ export default class Alioss {
     return hmac(
       'SHA-1',
       `DELETE\n\n\n${time}\nx-oss-date:${time}\n/${this.#bucket}/${key}`,
-      APP_KEY,
+      this.#appkey,
       'base64'
     ).then(signature =>
       fetch(`${this.#api}/${key}`, {
         method: 'DELETE',
         headers: {
-          'content-type': void 0,
-          authorization: `OSS ${APP_ID}:${signature}`,
+          authorization: `OSS ${this.#appid}:${signature}`,
           'x-oss-date': time
         }
       })