fix chrome 内存占用过高的问题 (#364)

Author: winddies

package.json

@@ -1,7 +1,7 @@
 {
   "name": "qiniu-js",
   "jsName": "qiniu",
-  "version": "2.2.1",
+  "version": "2.2.2",
   "private": false,
   "description": "Javascript SDK for Qiniu Resource (Cloud) Storage AP",
   "main": "dist/qiniu.min.js",

src/upload.js

@@ -12,13 +12,12 @@ import {
   getHeadersForChunkUpload,
   getHeadersForMkFile,
   request,
-  readAsArrayBuffer,
+  computeMd5,
   getUploadUrl,
   filterParams
 } from "./utils";
 
 import { Pool } from "./pool";
-import SparkMD5 from "spark-md5";
 
 let BLOCK_SIZE = 4 * 1024 * 1024;
 
@@ -205,11 +204,8 @@ export class UploadManager {
       return reuseSaved();
     }
 
-    return readAsArrayBuffer(chunk).then(body => {
+    return computeMd5(chunk).then(md5 => {
 
-      let spark = new SparkMD5.ArrayBuffer();
-      spark.append(body);
-      let md5 = spark.end();
       if (savedReusable && md5 === info.md5) {
         return reuseSaved();
       }
@@ -224,7 +220,7 @@ export class UploadManager {
       return request(requestUrl, {
         method,
         headers,
-        body,
+        body: chunk,
         onProgress,
         onCreate
       }).then(response => {

src/utils.js

@@ -1,5 +1,6 @@
 import { urlSafeBase64Encode, urlSafeBase64Decode } from "./base64";
 import { regionUphostMap } from "./config";
+import SparkMD5 from "spark-md5";
 
 // 对上传块本地存储时间检验是否过期
 // TODO: 最好用服务器时间来做判断
@@ -113,6 +114,14 @@ export function createXHR() {
   return new window.ActiveXObject("Microsoft.XMLHTTP");
 }
 
+export function computeMd5(data) {
+  return readAsArrayBuffer(data).then(buffer => {
+    let spark = new SparkMD5.ArrayBuffer();
+    spark.append(buffer);
+    return spark.end();
+  });
+}
+
 export function readAsArrayBuffer(data) {
   return new Promise((resolve, reject) => {
     let reader = new FileReader();