NodeJS mini-app for querying MongoDB

gistfile1.txt

var express = require('express')
  , mongoskin = require('mongoskin')
  , bodyParser = require('body-parser')

var path = require('path');

var app = express()
app.set('views', path.join(__dirname, 'views'));
app.use(express.static(path.join(__dirname, 'public')));
app.use(bodyParser())


var db = mongoskin.db('mongodb://@localhost:27017/elite-dangerous-api', {safe:true})

app.param('collectionName', function(req, res, next, collectionName){
  req.collection = db.collection(collectionName)
  return next()
})

app.get('/', function(req, res, next) {
  res.send('please select a collection, e.g., /collections/messages')
})

app.get('/collections/:collectionName', function(req, res, next) {
  req.collection.find({} ,{ limit:10, sort: ['timestamp',-1]}).toArray(function(e, results){
    if (e) return next(e)
    res.send(results)
  })
})

app.get('/collections/:collectionName/at/:at_timestamp', function(req, res, next) {
  at_timestamp = parseInt(req.params.at_timestamp)
  req.collection.find({ timestamp: at_timestamp },{ commander: true }).toArray(function(e, results){
    if (e) return next(e)
    res.send(results)
  })
})

app.get('/collections/:collectionName/from/:from_timestamp/to/:to_timestamp', function(req, res, next) {
  from_timestamp = parseInt(req.param.from_timestamp)
  to_timestamp = parseInt(req.param.to_timestamp)
  req.collection.find({ timestamp: { $gt: from_timestamp, $lt: to_timestamp }} ,{ sort: [['timestamp',-1]]}).toArray(function(e, results){
    if (e) return next(e)
    res.send(results)
  })
})

app.get('/collections/:collectionName/commodity/:commodity_name', function(req, res, next) {
  commodity_name = req.params.commodity_name
  
  req.collection.aggregate([
    { $sort: { timestamp: -1 }},
    { $limit : 100 },
    { $match: { 'lastStarport.commodities': { $elemMatch : { 'name': commodity_name }}}},
    { $unwind: '$lastStarport.commodities' }, { $match: {'lastStarport.commodities.name': commodity_name}},
    { "$project": { "timestamp": 1, "lastStarport.commodities.name": 1, "lastStarport.commodities.buyPrice": 1, "lastStarport.commodities.sellPrice": 1, "lastStarport.commodities.meanPrice": 1 }}
  ], function(e, results){
    if (e) return next(e)
    res.send(results)
  })
})