源代码在GitHub - 629y/course: Spring Cloud + Vue前后端分离-在线课程
Spring Cloud + Vue前后端分离-第9章 大文件断点续与极速秒传
作为一个视频网站,一个文件小则几十M,大则上G,上传一个大文件受网络影响很大,文件越大,上传失败率越高
我们要完善文件上传功能,支持断点续传,当文件上传到一半,网络断了,下次再上传时,只上传剩下的部分,这就是断点续传。
极速秒传,听起来很高深,原理其实很简单,就是开始上传前,先检查一下文件是否上传过了,如果已上传过,直接弹出提示,极速秒传成功。
9-1 分片传输的试探
一个文件有10M,每个分片定义为1M,那这个文件就会被分为10片进行传输。
分片上传
1.大文件断点续传与极速秒传:增加big-file组件,分片传输测试成功
把file.vue复制一份重命名big-file.vue
big-file.vue
section.vue
big-file.vue
分片合并
1.大文件断点续传与极速秒传:分片合并测试成功
UploadController.java
9-2 分片上传功能开发1
文件分片管理的模型设计
1.大文件断点续传与极速秒传:文件表增加分片相关字段
all.sql
generatorConfig.xml
分片数据传输
1.大文件断点续传与极速秒传:分片相关的数据传输
经验分享:对于一些不涉及安全性的数据,可以交由前端来计算,这样可以减轻服务端的压力
FileDto.java
big-file.vue
UploadController.java
文件标识的设计
1.大文件断点续传与极速秒传:使用文件生成md5签名,作为文件标识
数据库设计:上传第一个分片时,插入一条记录,上传之后的分片,都是更新记录,只需更新shard_index字段,当然也包括updated_at
数据库设计:shard_index和shard_total的值相等时,表示所有的分片都已上传完成。
数据库设计:不管上传第几个分片,传输的key值是一样的,key跟文件相关,跟分片无关。
big-file.vue
MD5信息摘要算法,常用于密码加密传输与存储,会生成128位二制数,每4个二进制可以转为1个16进制数字,结果是32个16进制数字
UploadController.java
md5.js
var KEY = "!@#QWERT";
/*
* Configurable variables. You may need to tweak these to be compatible with
* the server-side, but the defaults work in most cases.
*/
var hexcase = 0; /* hex output format. 0 - lowercase; 1 - uppercase */
var b64pad = ""; /* base-64 pad character. "=" for strict RFC compliance */
var chrsz = 8; /* bits per input character. 8 - ASCII; 16 - Unicode */
/*
* These are the functions you'll usually want to call
* They take string arguments and return either hex or base-64 encoded strings
*/
function hex_md5(s){ return binl2hex(core_md5(str2binl(s), s.length * chrsz));}
function b64_md5(s){ return binl2b64(core_md5(str2binl(s), s.length * chrsz));}
function str_md5(s){ return binl2str(core_md5(str2binl(s), s.length * chrsz));}
function hex_hmac_md5(key, data) { return binl2hex(core_hmac_md5(key, data)); }
function b64_hmac_md5(key, data) { return binl2b64(core_hmac_md5(key, data)); }
function str_hmac_md5(key, data) { return binl2str(core_hmac_md5(key, data)); }
/*
* Perform a simple self-test to see if the VM is working
*/
function md5_vm_test()
{
return hex_md5("abc") == "900150983cd24fb0d6963f7d28e17f72";
}
/*
* Calculate the MD5 of an array of little-endian words, and a bit length
*/
function core_md5(x, len)
{
/* append padding */
x[len >> 5] |= 0x80 << ((len) % 32);
x[(((len + 64) >>> 9) << 4) + 14] = len;
var a = 1732584193;
var b = -271733879;
var c = -1732584194;
var d = 271733878;
for(var i = 0; i < x.length; i += 16)
{
var olda = a;
var oldb = b;
var oldc = c;
var oldd = d;
a = md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936);
d = md5_ff(d, a, b, c, x[i+ 1], 12, -389564586);
c = md5_ff(c, d, a, b, x[i+ 2], 17, 606105819);
b = md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330);
a = md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897);
d = md5_ff(d, a, b, c, x[i+ 5], 12, 1200080426);
c = md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341);
b = md5_ff(b, c, d, a, x[i+ 7], 22, -45705983);
a = md5_ff(a, b, c, d, x[i+ 8], 7 , 1770035416);
d = md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417);
c = md5_ff(c, d, a, b, x[i+10], 17, -42063);
b = md5_ff(b, c, d, a, x[i+11], 22, -1990404162);
a = md5_ff(a, b, c, d, x[i+12], 7 , 1804603682);
d = md5_ff(d, a, b, c, x[i+13], 12, -40341101);
c = md5_ff(c, d, a, b, x[i+14], 17, -1502002290);
b = md5_ff(b, c, d, a, x[i+15], 22, 1236535329);
a = md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510);
d = md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632);
c = md5_gg(c, d, a, b, x[i+11], 14, 643717713);
b = md5_gg(b, c, d, a, x[i+ 0], 20, -373897302);
a = md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691);
d = md5_gg(d, a, b, c, x[i+10], 9 , 38016083);
c = md5_gg(c, d, a, b, x[i+15], 14, -660478335);
b = md5_gg(b, c, d, a, x[i+ 4], 20, -405537848);
a = md5_gg(a, b, c, d, x[i+ 9], 5 , 568446438);
d = md5_gg(d, a, b, c, x[i+14], 9 , -1019803690);
c = md5_gg(c, d, a, b, x[i+ 3], 14, -187363961);
b = md5_gg(b, c, d, a, x[i+ 8], 20, 1163531501);
a = md5_gg(a, b, c, d, x[i+13], 5 , -1444681467);
d = md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784);
c = md5_gg(c, d, a, b, x[i+ 7], 14, 1735328473);
b = md5_gg(b, c, d, a, x[i+12], 20, -1926607734);
a = md5_hh(a, b, c, d, x[i+ 5], 4 , -378558);
d = md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463);
c = md5_hh(c, d, a, b, x[i+11], 16, 1839030562);
b = md5_hh(b, c, d, a, x[i+14], 23, -35309556);
a = md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060);
d = md5_hh(d, a, b, c, x[i+ 4], 11, 1272893353);
c = md5_hh(c, d, a, b, x[i+ 7], 16, -155497632);
b = md5_hh(b, c, d, a, x[i+10], 23, -1094730640);
a = md5_hh(a, b, c, d, x[i+13], 4 , 681279174);
d = md5_hh(d, a, b, c, x[i+ 0], 11, -358537222);
c = md5_hh(c, d, a, b, x[i+ 3], 16, -722521979);
b = md5_hh(b, c, d, a, x[i+ 6], 23, 76029189);
a = md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487);
d = md5_hh(d, a, b, c, x[i+12], 11, -421815835);
c = md5_hh(c, d, a, b, x[i+15], 16, 530742520);
b = md5_hh(b, c, d, a, x[i+ 2], 23, -995338651);
a = md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844);
d = md5_ii(d, a, b, c, x[i+ 7], 10, 1126891415);
c = md5_ii(c, d, a, b, x[i+14], 15, -1416354905);
b = md5_ii(b, c, d, a, x[i+ 5], 21, -57434055);
a = md5_ii(a, b, c, d, x[i+12], 6 , 1700485571);
d = md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606);
c = md5_ii(c, d, a, b, x[i+10], 15, -1051523);
b = md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799);
a = md5_ii(a, b, c, d, x[i+ 8], 6 , 1873313359);
d = md5_ii(d, a, b, c, x[i+15], 10, -30611744);
c = md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380);
b = md5_ii(b, c, d, a, x[i+13], 21, 1309151649);
a = md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070);
d = md5_ii(d, a, b, c, x[i+11], 10, -1120210379);
c = md5_ii(c, d, a, b, x[i+ 2], 15, 718787259);
b = md5_ii(b, c, d, a, x[i+ 9], 21, -343485551);
a = safe_add(a, olda);
b = safe_add(b, oldb);
c = safe_add(c, oldc);
d = safe_add(d, oldd);
}
return Array(a, b, c, d);
}
/*
* These functions implement the four basic operations the algorithm uses.
*/
function md5_cmn(q, a, b, x, s, t)
{
return safe_add(bit_rol(safe_add(safe_add(a, q), safe_add(x, t)), s),b);
}
function md5_ff(a, b, c, d, x, s, t)
{
return md5_cmn((b & c) | ((~b) & d), a, b, x, s, t);
}
function md5_gg(a, b, c, d, x, s, t)
{
return md5_cmn((b & d) | (c & (~d)), a, b, x, s, t);
}
function md5_hh(a, b, c, d, x, s, t)
{
return md5_cmn(b ^ c ^ d, a, b, x, s, t);
}
function md5_ii(a, b, c, d, x, s, t)
{
return md5_cmn(c ^ (b | (~d)), a, b, x, s, t);
}
/*
* Calculate the HMAC-MD5, of a key and some data
*/
function core_hmac_md5(key, data)
{
var bkey = str2binl(key);
if(bkey.length > 16) bkey = core_md5(bkey, key.length * chrsz);
var ipad = Array(16), opad = Array(16);
for(var i = 0; i < 16; i++)
{
ipad[i] = bkey[i] ^ 0x36363636;
opad[i] = bkey[i] ^ 0x5C5C5C5C;
}
var hash = core_md5(ipad.concat(str2binl(data)), 512 + data.length * chrsz);
return core_md5(opad.concat(hash), 512 + 128);
}
/*
* Add integers, wrapping at 2^32. This uses 16-bit operations internally
* to work around bugs in some JS interpreters.
*/
function safe_add(x, y)
{
var lsw = (x & 0xFFFF) + (y & 0xFFFF);
var msw = (x >> 16) + (y >> 16) + (lsw >> 16);
return (msw << 16) | (lsw & 0xFFFF);
}
/*
* Bitwise rotate a 32-bit number to the left.
*/
function bit_rol(num, cnt)
{
return (num << cnt) | (num >>> (32 - cnt));
}
/*
* Convert a string to an array of little-endian words
* If chrsz is ASCII, characters >255 have their hi-byte silently ignored.
*/
function str2binl(str)
{
var bin = Array();
var mask = (1 << chrsz) - 1;
for(var i = 0; i < str.length * chrsz; i += chrsz)
bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (i%32);
return bin;
}
/*
* Convert an array of little-endian words to a string
*/
function binl2str(bin)
{
var str = "";
var mask = (1 << chrsz) - 1;
for(var i = 0; i < bin.length * 32; i += chrsz)
str += String.fromCharCode((bin[i>>5] >>> (i % 32)) & mask);
return str;
}
/*
* Convert an array of little-endian words to a hex string.
*/
function binl2hex(binarray)
{
var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
var str = "";
for(var i = 0; i < binarray.length * 4; i++)
{
str += hex_tab.charAt((binarray[i>>2] >> ((i%4)*8+4)) & 0xF) +
hex_tab.charAt((binarray[i>>2] >> ((i%4)*8 )) & 0xF);
}
return str;
}
/*
* Convert an array of little-endian words to a base-64 string
*/
function binl2b64(binarray)
{
var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
var str = "";
for(var i = 0; i < binarray.length * 4; i += 3)
{
var triplet = (((binarray[i >> 2] >> 8 * ( i %4)) & 0xFF) << 16)
| (((binarray[i+1 >> 2] >> 8 * ((i+1)%4)) & 0xFF) << 8 )
| ((binarray[i+2 >> 2] >> 8 * ((i+2)%4)) & 0xFF);
for(var j = 0; j < 4; j++)
{
if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;
else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);
}
}
return str;
}
index.html
big-file.vue
tool.js
1.大文件断点续传与极速秒传:根据文件标识来新增或修改文件记录,修改分片索引从1开始
实际使用场景中,一个文件太大,当第一次上传一半,失败了。第二次再上传时,有可能隔了一天或更久。
FileService.java
big-file.vue
此时是干净的,我们进行测试
完成,没有多余的数据
9-3 分片上传功能开发2
分片数据格式转换,统一系列前后端数据交互传参
1.大文件断点续传与极速秒传:分片数据改成base64 进行传输,后端统一用RequestBody 接收数据
big-file.vue
FileDto.java
Base64ToMultipartFile.java
package com.course.server.util;
import org.springframework.web.multipart.MultipartFile;
import sun.misc.BASE64Decoder;
import java.io.*;
public class Base64ToMultipartFile implements MultipartFile {
private final byte[] imgContent;
private final String header;
public Base64ToMultipartFile(byte[] imgContent, String header) {
this.imgContent = imgContent;
this.header = header.split(";")[0];
}
@Override
public String getName() {
// TODO - implementation depends on your requirements
return System.currentTimeMillis() + Math.random() + "." + header.split("/")[1];
}
@Override
public String getOriginalFilename() {
// TODO - implementation depends on your requirements
return System.currentTimeMillis() + (int) Math.random() * 10000 + "." + header.split("/")[1];
}
@Override
public String getContentType() {
// TODO - implementation depends on your requirements
return header.split(":")[1];
}
@Override
public boolean isEmpty() {
return imgContent == null || imgContent.length == 0;
}
@Override
public long getSize() {
return imgContent.length;
}
@Override
public byte[] getBytes() throws IOException {
return imgContent;
}
@Override
public InputStream getInputStream() throws IOException {
return new ByteArrayInputStream(imgContent);
}
@Override
public void transferTo(File dest) throws IOException, IllegalStateException {
new FileOutputStream(dest).write(imgContent);
}
public static MultipartFile base64ToMultipart(String base64) {
try {
String[] baseStrs = base64.split(",");
BASE64Decoder decoder = new BASE64Decoder();
byte[] b = new byte[0];
b = decoder.decodeBuffer(baseStrs[1]);
for(int i = 0; i < b.length; ++i) {
if (b[i] < 0) {
b[i] += 256;
}
}
return new Base64ToMultipartFile(b, baseStrs[0]);
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
}
UploadController.java
测试
base64格式:文件说明+“,”+文件内容
将文件转成base64 进行传输,优势是变成了常见的字符串类型,劣势是传输的数据会变大。
idea 的控制台默认大小是1M,可通过在设置中搜索console,修改默认配置
LogAspect.java
我们其它的业务表中,不要用shard字段,否则也会不打印日志
设置分片文件名
1.大文件断点续传与极速秒传:设置分片文件名,以分片索引结尾
小提示:当字符串拼接个数太多时,不要使用+,而是使用StringBuffer
UploadController.java
测试
这个日志可以删去,太长了
big-file.vue
支持连续上传多个分片
1.大文件断点续传与极速秒传:重构文件上传代码,将上传功能提取成一个单独的upload方法,使用递归调用upload方法,实现连续上传多个分片功能
在上传结束时,做个判断,如果shardIndex == shardTotal ,表示所有分片都上传完成了,如果shardIndex < shardTotal,继续上传下一个分片
重构
我们把生成的方法剪切到后面
把方法都放到下面来
递归,不断的重复做某一件事(上传分片),直到某个条件成立 (shardIndex == shardTotal) ,退出重复做的事。初学者慎用,容易陷入无限递归,跳不出来。
测试
9-4 分片合并功能开发
按分片顺序合并成原始文件
1.大文件断点续传与极速秒传:按分片顺序合并成原始文件
UploadController.java
package com.course.file.controller.admin;
import com.course.server.dto.FileDto;
import com.course.server.dto.ResponseDto;
import com.course.server.enums.FileUseEnum;
import com.course.server.service.FileService;
import com.course.server.util.Base64ToMultipartFile;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import javax.annotation.Resource;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
@RequestMapping("/admin")
@RestController
public class UploadController {
private static final Logger LOG = LoggerFactory.getLogger(UploadController.class);
public static final String BUSINESS_NAME= "文件上传";
//@Value,注入属性值
@Value("${file.domain}")
private String FILE_DOMAIN;
@Value("${file.path}")
private String FILE_PATH;
@Resource
private FileService fileService;
@RequestMapping("/upload")
public ResponseDto upload(@RequestBody FileDto fileDto) throws Exception {
LOG.info("上传文件开始");
String use = fileDto.getUse();
String key = fileDto.getKey();
String suffix = fileDto.getSuffix();
String shardBase64 = fileDto.getShard();
MultipartFile shard = Base64ToMultipartFile.base64ToMultipart(shardBase64);
//保存文件到本地
FileUseEnum useEnum = FileUseEnum.getByCode(use);
//如果文件夹不存在则创建
String dir = useEnum.name().toLowerCase();
File fullDir = new File(FILE_PATH + dir);
if(!fullDir.exists()){
fullDir.mkdirs();
}
//String path = dir + File.separator + key + "." + suffix + "." +fileDto.getShardIndex();
//小提示:当字符串拼接个数太多时,不要使用+,而是使用StringBuffer
String path = new StringBuffer(dir)
.append(File.separator)
.append(key)
.append(".")
.append(suffix)
.toString();//course/6sfSqfOwzmik4A4icMYuUe.mp4
String localPath = new StringBuffer(path)
.append(".")
.append(fileDto.getShardIndex())
.toString();//course/6sfSqfOwzmik4A4icMYuUe.mp4.1
String fullPath =FILE_PATH + localPath;
File dest = new File(fullPath);
shard.transferTo(dest);
LOG.info(dest.getAbsolutePath());
LOG.info("保存文件记录开始");
fileDto.setPath(path);
fileService.save(fileDto);
ResponseDto responseDto = new ResponseDto();
fileDto.setPath(FILE_DOMAIN + path);
responseDto.setContent(fileDto);
if (fileDto.getShardIndex() == fileDto.getShardTotal()){
this.merge(fileDto);
}
return responseDto;
}
public void merge(FileDto fileDto) throws Exception {
LOG.info("合并分片开始");
String path = fileDto.getPath();//全路径 http://127.0.0.1:9000/file/f/course/6sfSqfOwzmik4A4icMYuUe.mp4
//merge里面的方法,只需要相对路径
path = path.replace(FILE_DOMAIN,"");//course/6sfSqfOwzmik4A4icMYuUe.mp4
Integer shardTotal = fileDto.getShardTotal();
File newFile = new File(FILE_PATH + path);
FileOutputStream outputStream = new FileOutputStream(newFile, true);//文件追加写入
FileInputStream fileInputStream = null;//分片文件
byte[] byt = new byte[10 * 1024 * 1024];
int len;
try {
for (int i = 0; i < shardTotal; i++) {
//读取第i个分片
fileInputStream = new FileInputStream(FILE_PATH + path + "." + (i + 1));
course/6sfSqfOwzmik4A4icMYuUe.mp4.1
while ((len = fileInputStream.read(byt)) != -1) {
outputStream.write(byt, 0, len);
}
}
} catch (IOException e) {
LOG.error("分片合并异常", e);
}finally {
try{
if(fileInputStream != null){
fileInputStream.close();
}
outputStream.close();
LOG.info("io流关闭");
}catch (Exception e){
LOG.info("io流关闭",e);
}
}
LOG.info("合并分片结束");
}
}
merge里面的方法,只需要相对路径
保存到本地的分片名是xxx.mp4.1,但是我们返给前端和保存进数据库的path 都用xxx.mp4
测试
合并完成后删除多余分片
1.大文件断点续传与极速秒传:合并成原始文件后,删除所有分片
UploadController.java
big-file.vue
测试
9-5 分片检查与极速秒传
上传分片之前先进行分片检查
1.大文件断点续传与极速秒传:上传分片之前先进行分片检查,支持断点续传
开始上传之前,先检查一下当前的文件是否上传过了(数据库是否有记录),如果上传过了,已经传到第几个分片了。
FileService.java
UploadController.java
big-file.vue
测试
全初始化再次测试上传一半的结果
big-file.vue
也就是说现在只能上传第一个、第二个分片
只请求了两次,现在把代码恢复
再次测试
确实是从中间开始继续上传
极速秒传
1.大文件断点续传与极速秒传:支持极速秒传
big-file.vue
UploadController.java
测试
上传成功,但没有点击保存
再次上传,即为文件极速秒传成功,换一个也是可以
增加上传进度条
1.大文件断点续传与极速秒传:增加上传进度条组件
文件被分成四个分片,所以每个分片上传完,进度条就加25%
可以做成vue 组件,也可以做成js工具类,做成vue 组件的话,就只能在vue框架中使用,做成js 工具类的话,可以在jsp页面,thymeleaf模板页面、angular等前端框架中直接使用。
progress.js
Progress = {
show: function (width) {
let _this = this;
_this.width = width;
if ($("#progress-div").length > 0) {
$(".progress").attr("data-percent", width);
$(".progress-bar").width(width + "%");
} else {
let progressDiv = "<div id=\"progress-div\" style=\"z-index: 10011;\n" +
" position: fixed;\n" +
" padding: 10px;\n" +
" margin: 0px 0px 0px -150px;\n" +
" width: 300px;\n" +
" top: 40%;\n" +
" left: 50%;\n" +
" text-align: center;\n" +
" height: 45px;\n" +
" color: rgb(0, 0, 0);\n" +
" border: 3px solid rgb(170, 170, 170);\n" +
" background-color: rgb(255, 255, 255);\n" +
" cursor: wait;\"><div class=\"progress pos-rel\" data-percent=\"" + width + "%\"><div class=\"progress-bar\"></div></div></div>";
$("#progress-div").remove();
$("body").append(progressDiv);
// 背景遮罩
$("body").append($("<div id=\"progress-overlay\" style=\"z-index: 10010;\n" +
" border: none;\n" +
" margin: 0px;\n" +
" padding: 0px;\n" +
" width: 100%;\n" +
" height: 100%;\n" +
" top: 0px;\n" +
" left: 0px;\n" +
" background-color: rgb(0, 0, 0);\n" +
" opacity: 0.6;\n" +
" cursor: wait;\n" +
" position: fixed;\"></div>"));
$(".progress-bar").width(width + "%");
}
},
hide: function () {
setTimeout(function () {
$("#progress-div").remove();
//progress-div:显示的进度条;
//progress-overlay:背景遮罩,将页面所有的元素挡住,不可点击任何地方,常用于防止重复提交
$("#progress-overlay").remove();
}, 1000);
//上传到100%时,应该关闭进度条,但是一关闭,100%这个值就会一闪而过,所以为了用户体验,故意延迟1秒
}
};
progress-div:显示的进度条;
progress-overlay:背景遮罩,将页面所有的元素挡住,不可点击任何地方,常用于防止重复提交
上传到100%时,应该关闭进度条,但是一关闭,100%这个值就会一闪而过,所以为了用户体验,故意延迟1秒
big-file.vue
做成js全局工具类,可以直接使用,不需要import
index.html
loading.js
如果不改,loading按钮会被模态框挡住,看不到转圈圈图片
UploadController.java
测试
再次上传 文件极速秒传成功
讲师头像和课程封面改为用大文件组件
1.大文件断点续传与极速秒传:讲师头像和课程封面改为用大文件组件
course.vue
teacher.vue
修复了一个Bug
big-file.vue
测试
9-6 文件上传流程图
开始
结束