Async JS/Node - Parallel Callbacks Example

example.js

function getTweetsPostsRepos(username, callback) {
  var count = 0
    , results = []

  function somethingFinished(err, result) {
    count += 1
    results.push(result)
    
    if(count === 3) {
      callback(null, results)
    }
  }
  
  getTweets(username, function(err, results) {
    if(err) return callback(err)
    
    somethingFinished(null, results)
  })

  getPosts(username, function(err, results) {
    if(err) return callback(err)
    
    somethingFinished(null, results)
  })

  getRepos(username, function(err, results) {
    if(err) return callback(err)
    
    somethingFinished(null, results)
  })
}

getTweetsPostsRepos(username, function(err, tweetsPostsRepos) {
  if(err) {
    console.error(err)
  } else {
    console.log(username + ' has this stuff ' + tweetsPostsRepos)
  }
})