What the scope?

gistfile1.txt

I want to use a function so that i dont have to write the same logic over and over again in my calls to the find function on my MongoDb collections.

Here's the function I want, but notice that it contains 'self.res'.  That's cause i just ripped it out of my find(...) call (below).  Previously, when this was just an annoymous function, self.res is the HTTP response that we're building.  

So how to i access self.res in my callback, if I use a named function, instead of an anonymous function in my find?

function findHandler(err, docs) {
  if (!err) {
    // Return Success & JSON Content-type
    var length = docs.length;
    writeMeta(self.res,200,url,length);

    // Process results from Mongo
    docs.forEach(function(e,i,a) {
      //console.log(e,i,a);
      self.res.write(JSON.stringify(e)+'\n');
    });
    self.res.end('\n');
  } else {
    getHandlerError(self.res,url);
  }
}


Flatiron route for my /force API endpoint:

app.router.get('/force',function() {
  // Setup
  var self = this;
  var method = 'GET';
  var url = '/force';
  var body = self.req.body;

  // Create metrics data.
  var shlock = new Shlock('api', method, url);
  shlock.body = body;
  console.log(url,method,shlock);

  // Check for query string
  var query = self.req.query;
  if (!isQueryValid(query)) {
    writeMeta(self.res,400,url,0);
    self.res.end('\n');
  } else {
    // Handle count=true
    if (query.hasOwnProperty('count') &&
        query.count === 'true') {
      var only   = getFindCriteria('force',query);
      force.count(only,function(err,docs) {
        writeMeta(self.res,200,url,docs);
        self.res.end('\n');
      });
    } else {
      // Handle paging
      if (query.hasOwnProperty('page')) {
        var only = getFindCriteria('force',query);
        var fields = getFindFields('force',query);
        force.find(only,fields,function(err,docs) {
          var length = docs.length;
          writeMeta(self.res,200,url,length);

          // Process results from Mongo
          docs.forEach(function(e,i,a) {
            //console.log(e,i,a);
            self.res.write(JSON.stringify(e)+'\n');
          });
          self.res.end('\n');
        }).skip(PAGE_SIZE*query.page)
          .limit(PAGE_SIZE);
      } else {
        // Query Mongo
        var only = getFindCriteria('force',query);
        var fields = getFindFields('force',query);
        force.find(only,fields,findHandler);
      }
    }
  }
});