Why isn't this simple Node program non-blocking?

Question

I've installed node and am running some simple 'hello world' style programs to better grasp what's going on.

I'm confused as to why the following code seems to run in a blocking fashion. When I open my browser to localhost:8080 after 5 seconds both "Process started..." and "Process complete." appear on the screen. I would expect "Process started..." to appear immediately and then "Process complete." to follow 5 seconds later. Any ideas as to why the timeout effects both pieces of this code? This code is saved in a file called 'hello.js' that I simply run with 'node hello.js'.

var http = require('http');

http.createServer(function(request,response) {
    response.writeHead(200);
    response.write("Process started...");
    setTimeout(function() {
        response.write("Process complete.");
        response.end();
    }, 5000);
}).listen(8080);

http://stackoverflow.com/questions/6258210/how-can-i-output-data-before-i-end-the-response — Matthew Lock, Jun 27 '14 at 02:55

score 3 · Accepted Answer · answered Jun 27 '14 at 02:51

3

Your browser is most likely buffering the response. Try hitting it with curl (curl -N http://localhost:8080) instead and you'll see the difference.

answered Jun 27 '14 at 02:51

mscdex

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Why isn't this simple Node program non-blocking?

1 Answers1