Bubble

Domains for the poor man.

Flow-control for cascading callbacks.

Aborts groups of callbacks.

With timeouts (if you will).

Inspired by substack/node-toss.

Example:

var bubble = require('bubble')
var timeout = 2000
 
require('http').createServer(function(req, res) {
 
  var b = bubble(timeout, function(err, file_c_data) {
    if (err) {
      res.writeHead(500)
      res.write(err.message)
    } else {
      res.end(file_c_data)
    }
  });
 
  fs.readFile('./file_a', b(function(file_a_data) {
    fs.readFile('./file_b', b(function(file_b_data) {
      fs.readFile('./file_c', b())
    })
  }))
})

You can also leave out the timeout:

var b = bubble(function(err, file_c_data) {
  // ...
});
 
fs.readFile('./file_a', b(function(file_a_data) {
  // ...
});
 

You can also leave out the last wrapper if you're not doing more IO and don't care about the callback values:

var bubble = require('bubble')
var timeout = 2000
 
require('http').createServer(function(req, res) {
 
  var file_c_data;
 
  var b = bubble(timeout, function(err) {
    if (err) {
      res.writeHead(500)
      res.write(err.message)
    } else {
      res.end(file_c_data)
    }
  });
 
  fs.readFile('./file_a', b(function(file_a_data) {
    fs.readFile('./file_b', b(function(file_b_data) {
      fs.readFile('./file_c', function(err, value) {
        if (err) {
          // handle error
        }
        file_c_data = data;
        console.log('file ended, but bubble callback will be called anyway');
      })
    })
  }))
})