express-chunked-file-upload

This package is an express middleware for handling chunked file uploads.

Installation

npm install --save @rstcruzo/express-chunked-file-upload

Usage

express-chunked-file-upload will receive each chunk save it in a /tmp directory and then, when finished uploading all chunks, it will merge all the chunks and save the original file in the final destination.

Nodejs code:

const express = require('express');
const ChunkedUpload = require('@rstcruzo/express-chunked-file-upload');

const app = express();

const chunkedUpload = new ChunkedUpload({ filePath: 'media/' });

app.post('/upload', chunkedUpload.makeMiddleware(), (req, res) => {
    if (req.filePart === 0) {
        // ... Do something when file upload starts
    }
    if (req.isLastPart) {
        // ... Do something when file upload finishes
    }
});

Client js code to send first chunk:

var myHeaders = new Headers();
myHeaders.append("file-chunk-id", "random-hash");
myHeaders.append("file-chunk-size", "60000");
myHeaders.append("Content-Range", "bytes 0-60000/100000");

var formdata = new FormData();
formdata.append("file", fileInput.files[0], "filename.txt");

var requestOptions = {
    method: 'POST',
    headers: myHeaders,
    body: formdata,
    redirect: 'follow'
};

fetch("http://localhost:3000/", requestOptions)
    .then(response => response.text())
    .then(result => console.log(result))
    .catch(error => console.log('error', error));

Client js code to send second/last chunk:

var myHeaders = new Headers();
myHeaders.append("file-chunk-id", "random-hash");
myHeaders.append("file-chunk-size", "60000");
myHeaders.append("Content-Range", "bytes 60000-100000/100000");

var formdata = new FormData();
formdata.append("file", fileInput.files[0], "filename.txt");

var requestOptions = {
    method: 'POST',
    headers: myHeaders,
    body: formdata,
    redirect: 'follow'
};

fetch("http://localhost:3000/", requestOptions)
    .then(response => response.text())
    .then(result => console.log(result))
    .catch(error => console.log('error', error));

The three headers are required for this to work. Header names for chunk id and chunk size can be edited in options parameter for ChunkedUpload constructor:

const chunkedUpload = new ChunkedUpload(
    {
        filePath: 'media/',
        chunkIdHeader: 'another-header-name-for-id',
        chunkSizeHeader: 'antoher-header-name-for-size',
        fileField: 'image'
    }
);

Options

• filePath: Path to save files (default: '').
• chunkIdHeader: Header name for chunk id (default: 'file-chunk-id').
• chunkSizeHeader: Header name for chunk size (default: 'file-chunk-size').
• fileField: Field to process (default: 'file').

Request fields

• filePart: Part number uploaded, it goes from 0 to the total number of parts - 1 (req.filePart).
• isLastPart: Boolean that tells if the part uploaded is the last one (req.isLastPart). This means that now the original file is available at the destination path (filePath).