homework solution for M101JS

gistfile1.txt

var MongoClient = require('mongodb').MongoClient;

MongoClient.connect('mongodb://localhost:27017/school', function(err, db) {

  if(err) throw err;

  var _update = function(student) {
    db.collection('students').update({_id: student._id}, student, function(err, saved) {
        if (err) throw error;
        console.log('Successfully updated student');
    });
  }

  cursor = db.collection('students').find({});
  cursor.each(function(err, student) {
      var scores = student.scores;
      function compare(a,b) {
        if (a.score < b.score)
           return -1;
        if (a.score > b.score)
          return 1;
        return 0;
      }
      function homework(a) {
        if (a.type == 'homework')
           return -1;
        else
          return 1;
        return 0;
      }
      scores.sort(compare);
      scores.sort(homework);
      if (scores[0].type == 'homework') scores.shift();
      student.scores = scores;
      _update(student);
  });
});