title: Using nodejs async and request module
body: <p>I'm trying to use async and request module together but i don't understand how the callbacks get passed. My code is</p>
  
  <pre><code>var fetch = function(file, cb) {
      return request(file, cb);
  };
  
  async.map(['file1', 'file2', 'file3'], fetch, function(err, resp, body) {
      // is this function passed as an argument to _fetch_ 
      // or is it excecuted as a callback at the end of all the request?
      // if so how do i pass a callback to the _fetch_ function
      if(!err) console.log(body);
  });
  </code></pre>
  
  <p>I'm trying to fetch 3 files in order and concatenate the results. My head is stuck in callbacks I tryed and the different combinations I could think of. Google wasn't much help.</p>