Video streaming with HTML 5 via node.js

问题:

I'm trying to set up a web server that will support streaming video to an HTML5 video tag using node.js. Here's my code so far:

var range = request.headers.range;
var total = file.length;

var parts = range.replace(/bytes=/, "").split("-");
var partialstart = parts[0];
var partialend = parts[1];

var start = parseInt(partialstart, 10);
var end = partialend ? parseInt(partialend, 10) : total-1;

var chunksize = (end-start)+1;

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

Where "request" represents the http request, type is either "application/ogg" or "video/ogg" (I've tried both) and "file" is the .ogv file that's been read from the file system. Here are the response headers:

Content-Range   bytes 0-14270463/14270464
Accept-Ranges   bytes
Content-Length   14270464
Connection     keep-alive
Content-Type     video/ogg

I've examined the response headers and this code appears to be working fine, but there are a couple of problems:

1. The video appears to load very slowly for being on a local network. From what I can tell examining the response using firebug, the file appears to be streamed in at about 150 kb/sec.
2. The video doesn't play at all. Even if I wait for the whole thing to load, the HTML 5 video tag just shows a big "x" instead of a movie in firefox.

Does anyone have any ideas as to what I can do to get video streaming working via node.js?

Thanks!
Chris

回答1:

I know this is a really old question, but as Google seems to like it I thought it would be worth pointing out that I wrote a Node.js video streaming module (Github, or via NPM) that's hopefully worth a look too.

回答2:

I was able to get this to work with some help from the nodejs forums:

http://groups.google.com/group/nodejs/browse_thread/thread/8339e0dc825c057f/822b2dd48f36e890

Highlights from the Google Groups thread:

Google chrome is known to first make a request with the range 0-1024 and then request the range "1024-".

response.end(file.slice(start, chunksize), "binary");

Then:

I was able to get the video to play no problems in firefox by setting the "connection" header to "close"

Then:

Seems that you are incorrectly computing the content-length:

var chunksize = (end-start)+1;

If start is 0 and end is 1, in your case chunksize is 2, and it should be 1.

回答3:

This solution does an asynchronous read of a server side video or audio media file ... it spins up a nodejs server at URL visible at

http://localhost:8888/

also it correctly handles client side HTML5 (browser/app) forward/back UI widget slider movements

save below code snippet as server side file :

media_server.js

... execute it on server side using

node media_server.js

enjoy

var http = require('http'),
    fs = require('fs'),
    util = require('util');

var path = "/path/to/local/video/or/audio/file/on/server.mp4";

var port = 8888;
var host = "localhost";

http.createServer(function (req, res) {

  var stat = fs.statSync(path);
  var total = stat.size;

  if (req.headers.range) {   // meaning client (browser) has moved the forward/back slider
                                         // which has sent this request back to this server logic ... cool
    var range = req.headers.range;
    var parts = range.replace(/bytes=/, "").split("-");
    var partialstart = parts[0];
    var partialend = parts[1];

    var start = parseInt(partialstart, 10);
    var end = partialend ? parseInt(partialend, 10) : total-1;
    var chunksize = (end-start)+1;
    console.log('RANGE: ' + start + ' - ' + end + ' = ' + chunksize);

    var file = fs.createReadStream(path, {start: start, end: end});
    res.writeHead(206, { 'Content-Range': 'bytes ' + start + '-' + end + '/' + total, 'Accept-Ranges': 'bytes', 'Content-Length': chunksize, 'Content-Type': 'video/mp4' });
    file.pipe(res);

  } else {

    console.log('ALL: ' + total);
    res.writeHead(200, { 'Content-Length': total, 'Content-Type': 'video/mp4' });
    fs.createReadStream(path).pipe(res);
  }
}).listen(port, host);

console.log("Server running at http://" + host + ":" + port + "/");

回答4:

Based on Sam9291's answer, I rewrote the function using createReadStream() and fixing some problems:

/**
 * Sends a static file to the HTTP client, supporting partial transfers.
 * 
 * @req HTTP request object
 * @res HTTP response object
 * @fn Path to file that should be sent
 * @contentType MIME type for the response (defaults to HTML)
 */      
function sendFile(req, res, fn, contentType) {

  contentType = contentType || "text/html";

  fs.stat(fn, function(err, stats) {
    var headers;

    if (err) {
      res.writeHead(404, {"Content-Type":"text/plain"});
      res.end("Could not read file");
      return;
    }

    var range = req.headers.range || "";    
    var total = stats.size;

    if (range) {

      var parts = range.replace(/bytes=/, "").split("-");
      var partialstart = parts[0];
      var partialend = parts[1];

      var start = parseInt(partialstart, 10);
      var end = partialend ? parseInt(partialend, 10) : total-1;

      var chunksize = (end-start)+1;

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

    } else {

      headers = { 
        "Accept-Ranges": "bytes", 
        "Content-Length": stats.size, 
        "Content-Type": contentType 
      };
      res.writeHead(200, headers);

    }

    var readStream = fs.createReadStream(fn, {start:start, end:end});
    readStream.pipe(res);    

  });

}

回答5:

I am using the MVC framework sails.js on top of Node.js and I managed to get it working fine with the following code:

/**
 * VideoController
 *
 * @module      :: Controller
 * @description :: Contains logic for handling requests.
 */

 var fs = require('fs');

module.exports = {

  /* e.g.
  sayHello: function (req, res) {
    res.send('hello world!');
  }
  */

  /**
   * /video/stream
   */ 
  stream: function (req,res) {

    // This will render the view: 
    // C:\Users\sam\Documents\Dev\Fun\mymoviebank/views/video/stream.ejs
    res.view();

  },

  play: function (req,res) {

    fs.readFile('/Users/sam/Videos/big_buck_bunny.mp4', function (err, data) {
      if (err) throw err;

      var range = req.headers.range;
        var total = data.length;

        var parts = range.replace(/bytes=/, "").split("-");
        var partialstart = parts[0];
        var partialend = parts[1];

        var start = parseInt(partialstart, 10);
        var end = partialend ? parseInt(partialend, 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' });
        res.end(data);

    });

  }

};

Hope this helps

回答6:

I found this solution which seems to be simpler and (unlike the checked answer) works for me. (I tried adapting the coffeescript solution at the end of that thread and it kind of worked once I dealt with the fact that the initial request (for "bytes=0-") blows it up.

http://elegantcode.com/2011/04/06/taking-baby-steps-with-node-js-pumping-data-between-streams/

My actual implementation:

function stream_response( res, file_path, content_type ){
    var readStream = fs.createReadStream(file_path);

    readStream.on('data', function(data) {
        var flushed = res.write(data);
        // Pause the read stream when the write stream gets saturated
        console.log( 'streaming data', file_path );
        if(!flushed){
            readStream.pause();
        }
    });

    res.on('drain', function() {
        // Resume the read stream when the write stream gets hungry 
        readStream.resume();
    });

    readStream.on('end', function() {
        res.end();
    });

    readStream.on('error', function(err) {
        console.error('Exception', err, 'while streaming', file_path);
        res.end();
    });

    res.writeHead(200, {'Content-Type': content_type});
}