https://github.com/imcuttle/mouploader
mobile Uploader Plugin
https://github.com/imcuttle/mouploader
Last synced: about 1 year ago
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mobile Uploader Plugin
- Host: GitHub
- URL: https://github.com/imcuttle/mouploader
- Owner: imcuttle
- Created: 2016-09-14T11:32:54.000Z (almost 10 years ago)
- Default Branch: master
- Last Pushed: 2024-07-30T16:13:22.000Z (almost 2 years ago)
- Last Synced: 2025-03-23T02:34:03.220Z (about 1 year ago)
- Language: JavaScript
- Size: 17.6 KB
- Stars: 30
- Watchers: 3
- Forks: 5
- Open Issues: 2
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# 分片上传与断点续传解决方案
上传文件，基本上是每一个网站应用都会具备的一个功能。对于一个网络存储应用，对于上传功能要求更是迫切。
如今市面上成熟上传插件，如`WebUploader`，"体积太大"，不适合于移动端上传；再加上作为一位程序员的"操守"，当然还是更喜欢自己造轮子。
于是花了一天半时间，`MoUploader`应运而生。为什么叫`MoUploader`呢？
`Mo`表示`Mobile`(其实更是因为我的绰号moyu)
## 关于实现原理
- 首先需要明确，上传这东西不仅仅是只需要前端就能完成的很好的，需要前端后端统一数据格式，从而实现断点续传。（所以，该文适合于全栈工程师，至少是想成为）
- 还有，为什么需要分片，不分片能实现断点续传吗？分片是为了充分利用网络带宽，加快上传速度；不分片也是能够实现断点续传的。详细参考 [HTML5文件上传组件深度剖析](http://fex.baidu.com/blog/2014/04/html5-uploader/).
分片上传与断点续传之间没有很直接的关系.
好了，进入正题
- 实现断点续传的前提是需要服务器记录某文件的上传进度，那么根据什么判断是不是同一个文件呢？可以利用文件内容求md5码，如果文件过大，求取md5码也是一个很长的过程，所以对于大文件，只能针对某一段数据进行计算，加上服务器对cookie用户信息的判断，得到相对唯一的key
- 在前端页面，需要将文件按照一定大小进行分片，一次请求只发送这一小片数据，所以我们可以同时发起多个请求。但一次同时请求的连接数不宜过多，服务器负载过重
对于文件分片操作，H5具有十分强大的File API，直接利用File对象的slice方法即可得到Blob对象.
至于同时传输数据的连接数控制逻辑，就需要花点脑子思考了
- 前端把数据顺利得传给服务器了，服务器只需要按照数据中给的开始字节位置，与读取到的文件片段数据，写入文件即可
更多信息就看源码吧！[MoUploader](https://github.com/moyuyc/moUploader)
## 功能实现
- 文件结构
```
file-upload/
├── bower_components/ # bower包
├── db.js # 数据操作接口
├── demo.html
├── md5.json # 数据
├── mouploader.js # 源码
├── README.md
└── server.js # demo.html服务, 建立在4040端口
1 directories, 8 files.
```
(打印文件目录树使用的是自己写的[print-dir](https://github.com/moyuyc/directory-tree))
- 怎么使用
1. 引入script，amd/cmd/...，
2. 使用MoUploader
```js
input.onchange = function (e) {
var self = this;
var moUploader = MoUploader({
files: this.files,
uploadUrl: '/upload',
request: false,
onBeforeUpload: function (index) {
if(index>=0) {
self.files[index].progress = appendUploading(self.files[index], index)
}
},
onOverAllProgress: function (index, loaded, total) {
console.log(loaded / total)
//setProgress(loaded / total, self.files[index].progress)
},
onLoad: function (index, chunkIndex, chunksNum) {
console.log('onLoad', this, arguments)
},
onAbort: function (index, chunkIndex, chunksNum) {
console.log('onAbort', this, arguments)
},
onError: function (index, chunkIndex, chunksNum) {
console.log('onError', this, arguments)
},
onContinue: function (file, md5, index) {
return new Promise(function(reslove, reject) {
var xhr = new XMLHttpRequest()
xhr.open('GET', '/getFile?md5='+md5, true);
xhr.send(null);
xhr.addEventListener('readystatechange', function () {
if(xhr.readyState === 4 && xhr.status === 200) {
var json = JSON.parse(xhr.responseText);
log(json)
reslove(json.pos)
}
})
})
}
})
// pause or continue upload
// if index < 0, will run for all files
// moUploader.pause(index);
// moUploader.continue(index);
}
```
3. 配置选项
```js
var default_ops = {
// chunk Size: byte
chunkSize: (1<<20) * 5,
// Number: request Number.
// Array: files requests.
// Boolean: open or close Slice, if false, chunkSize don't work.
request: 3,
files: [],
uploadUrl: '/',
// function: get uploaded pos.
// arguments: file, md5, index.
// need return a promise object which will return uploaded pos.
onContinue: null,
// if false, md5 will be setted by filename.
md5: true,
// md5Size: slice file 0 - md5Size for calculate md5
md5Size: (1<<20) * 50,
// called when before upload.
// arguments: file index or -1 (will begin upload)
onBeforeUpload: null,
// function: uploading progress listener.
// *only listen one request.*
// arguments: index, chunkIndex, chunksNum, loaded, total.
onProgress: null,
// function: overall uploading progress listener.
// arguments: index, loaded, total
onOverAllProgress: null,
// function: called when one request is ended.
// arguments: index, chunkIndex, chunksNum
onLoad: null,
// function: called when one request is aborted.
// arguments: index, chunkIndex, chunksNum
onAbort: null,
// function: called when one request happens error.
// arguments: index, chunkIndex, chunksNum
onError: null
}
```
4. 服务器数据处理 (Node.js)
数据分段写入文件
```js
function writeBuffer(bf, path, pos) {
var fd = fs.openSync(path, 'a+');
fs.writeSync(fd, bf, 0, bf.length, Number(pos) || 0)
console.log(`write buffer, pos: ${pos}, path: ${path}, length: ${bf.length}`)
}
function store(param, chunks) {
param.chunks = param.chunks || 1
param.chunk = param.chunk || 0
var p = path.join('./upload', param.name)
var bf = Buffer.concat(chunks);
var json = db.get(param.md5);
if(json) {
json.pos = parseInt(json.pos!=null?json.pos : 0)
json.size = parseInt(json.size!=null?json.size : 0)
}
if(!json || (json.pos+json.size) <= param.pos) {
// 新的数据pos比数据库中大，更新数据
param.size = bf.length
db.set(param.md5, param)
db.save();
writeBuffer(bf, p, param.pos || 0)
}
}
var multiparty = require('multiparty')
var form = new multiparty.Form({
autoFields: true,
autoFiles: false,
});
form.on('part', (part) => {
form.on('aborted', () => {
//意外退出或者暂停都会保存数据
console.log('aborted');
store(param, chunks)
})
var chunks = []
part.on('data', (data) => {
if(part.filename) {
chunks.push(data)
}
}).on('end', () => {
console.log('end')
store(param, chunks)
})
});
form.on('field', (name, value) => {
param[name] = value;
});
```