fkc/lib/use/stream.js

FKC application service framework.

'use strict';
const fs = require('fs');
module.exports = (req,res,obj) => {  
    const stat = fs.statSync(obj.url);
    const fileSize = stat.size;
    const range = req.headers.range;
    if (range) {
        const parts = range.replace(/bytes=/,'').split('-');
        const start = parseInt(parts[0], 10);
        const end = parts[1] ? parseInt(parts[1], 10):fileSize-1;
        const chunksize = (end - start) + 1;
        const head = { 
            'Accept-Ranges': 'bytes',
            'Content-Type': obj.type,
            'Content-Length': chunksize,
            'Content-Range': `bytes ${start}-${end}/${fileSize}`,
        };
        res.writeHead(206, head);
        fs.createReadStream(obj.url, { start, end }).pipe(res);
    } else {
        let head = {
            'Content-Length': fileSize,
            'Content-Type': obj.type,
        };
        if(obj.name) head['Content-Disposition'] = `attachment; filename="${encodeURI(obj.name)}"`;
        res.writeHead(200, head);
        fs.createReadStream(obj.url).pipe(res);
    }
}