validation done on server side

backend/app/people/inquisitor-validator.js

+var erroneous_name = new Error('Erroneous name')
+var erroneous_pet = new Error('Erroneous pet name')
+
+var areBadPetsHere = function (pets) {
+  if(pets.length == 0){
+    return false
+  }
+  var m = pets.map(function (pet) {
+    return pet == ''
+  })
+  return m.reduce(function (i,j) {
+    return i || j
+  })
+}
+
+var inquisitor = function (next) {
+  if(this.name == ''){
+    next(erroneous_name)
+  }
+  if(areBadPetsHere(this.pets)){
+    next(erroneous_pet)
+  }
+  next()
+}
+
+module.exports = inquisitor

backend/app/people/people.js

 var db = require('../db/db.js')
 var mongoose = require('mongoose')
+var inquisitor = require('./inquisitor-validator.js')
 
 var people = {}
 
 db.once('open',function () {
-  people.model = mongoose.model('People',{ name: String, pets: Array })
+  people.schema = new mongoose.Schema(
+  {
+    name: {
+      type: String,
+      required: true
+    },
+    pets: Array
+  })
+
+  people.schema.pre('save',inquisitor) // let the inquisitor validate and purge
+                                       // heretic (erroneous) data
+
+  people.model = mongoose.model('People',people.schema)
 
   people.index = function (callback) {
     people.model.find({}, callback)