Streaming a Video File to an Html5 Video Player With Node.Js So That the Video Controls Continue to Work

Streaming a video file to an html5 video player with Node.js so that the video controls continue to work?

The Accept Ranges header (the bit in writeHead()) is required for the HTML5 video controls to work.

I think instead of just blindly send the full file, you should first check the Accept Ranges header in the REQUEST, then read in and send just that bit. fs.createReadStream support start, and end option for that.

So I tried an example and it works. The code is not pretty but it is easy to understand. First we process the range header to get the start/end position. Then we use fs.stat to get the size of the file without reading the whole file into memory. Finally, use fs.createReadStream to send the requested part to the client.

var fs = require("fs"),
    http = require("http"),
    url = require("url"),
    path = require("path");

http.createServer(function (req, res) {
  if (req.url != "/movie.mp4") {
    res.writeHead(200, { "Content-Type": "text/html" });
    res.end('<video src="http://localhost:8888/movie.mp4" controls></video>');
  } else {
    var file = path.resolve(__dirname,"movie.mp4");
    fs.stat(file, function(err, stats) {
      if (err) {
        if (err.code === 'ENOENT') {
          // 404 Error if file not found
          return res.sendStatus(404);
        }
      res.end(err);
      }
      var range = req.headers.range;
      if (!range) {
       // 416 Wrong range
       return res.sendStatus(416);
      }
      var positions = range.replace(/bytes=/, "").split("-");
      var start = parseInt(positions[0], 10);
      var total = stats.size;
      var end = positions[1] ? parseInt(positions[1], 10) : total - 1;
      var chunksize = (end - start) + 1;

      res.writeHead(206, {
        "Content-Range": "bytes " + start + "-" + end + "/" + total,
        "Accept-Ranges": "bytes",
        "Content-Length": chunksize,
        "Content-Type": "video/mp4"
      });

      var stream = fs.createReadStream(file, { start: start, end: end })
        .on("open", function() {
          stream.pipe(res);
        }).on("error", function(err) {
          res.end(err);
        });
    });
  }
}).listen(8888);

Can the server respond with content-length less than requested range if proper headers are used

If you can't satisfy the requested range, you want to respond with 416, and include a Content-Range header telling the client what the satisfiable range actually is. See

https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/416

If you're really going to handle range requests yourself, you probably want to read the RFC. You need to gracefully handle badly formatted requests, unknown units, multiple ranges, etc. The page I linked above has a link to the current RFC.

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