Mongoose Model and Route handler for the same (REST API).

group.js

/**
 * Created with JetBrains WebStorm.
 * User: Matloob
 * Date: 9/12/13
 * Time: 12:06 PM
 * To change this template use File | Settings | File Templates.
 */

var mongoose = require('mongoose');
var Schema = mongoose.Schema;

var DATA_NOT_FOUND = "Group not found!";

// group or class

GroupSchema = new Schema({
    schoolId:       { type: Schema.ObjectId, ref: 'School' },
    teacherId:      { type: Schema.ObjectId, ref: 'User' },
    name:           String,
    description:    String,
    grade:          String,
    imageSrc:       { type: String, default: "" },
    createdBy:      { type: Schema.ObjectId, ref: 'User' },
    createdOn:      { type: Date, default: Date.now },
    isActive:       { type: Boolean, default: true }
});

GroupSchema.index({ name: 1 }, { unique: true });
GroupSchema.index({ schoolId: 1, teacherId: 1 });


GroupSchema.statics.findByQuery = function(query, done) {

    this.find(query)
        .populate('schoolId', 'name city state')
        .populate('teacherId', 'firstName lastName')
        .exec(function(err, data){

        if(err) return done(err);

        if (data.length == 0) {
            return done(new Error(DATA_NOT_FOUND));
        }

        return done(null, data);
    });
};

GroupSchema.statics.createGroup = function(newGroup, done){
    console.log("In create Group");

    this.create(newGroup, function(err, group){
        if (err) return done(err);

        console.log("New Group created");
        console.log(group);
        done(null, group);
    });
};

GroupSchema.statics.updateGroup = function(groupId, updates, done) {

    var query   = { _id: groupId };
    var options = { new: true };
    delete updates._id;

    this.findOneAndUpdate(query, updates, options, function(err, group) {

        if(err) return done(err);

        if (!group){
            return done(new Error( DATA_NOT_FOUND ));
        }
        console.log(group);
        return done(null, group);
    });
};

GroupSchema.statics.deleteGroup = function(groupId, done) {

    var self = this;

    var Student = require('./student');
    Student.findOne({ groupId: groupId }, function(err, data){
        if (data){
            if(err) return done(new Error("Cannot Delete: Group has student(s)!"));
        } else {
            if(err) return done(err);

            var query   = { _id: groupId };
            self.remove(query, function(err) {

                if(err) return done(err);

                return done(null, "Deleted!");
            });
        }
    });
};


var Group = mongoose.model("Group", GroupSchema);
module.exports = Group;

groups.js

/**
 * Created with JetBrains WebStorm.
 * User: Matloob
 * Date: 9/14/13
 * Time: 7:41 PM
 * To change this template use File | Settings | File Templates.
 */

var Group = require('../../app/models/group');
var ObjectId = require('mongoose').Types.ObjectId;

exports.createGroup = function(req, res) {

    var newGroup = createNewGroup(req.body);

    if (newGroup.errorMessage) {
        return res.send(newGroup.errorMessage);
    }
    newGroup.createdBy = ObjectId( (req.user._id + '') );

    Group.createGroup(newGroup, function(err, group){
        if(err) return res.send(err.message, 400);
        res.send(group);
    });

};

exports.getGroups = function(req, res) {

    var query = { createdBy: req.user._id, isActive: true };

    Group.findByQuery(query, function(err, data){

        if(err) return res.send(err.message, 400);

        res.send(data);
    });
};

exports.getGroup = function(req, res) {

    if (!req.params.id){
        return res.send("Please provide an id", 400);
    }

    var query = { _id: req.params.id, isActive: true };

    Group.findByQuery(query, function(err, data){

        if(err) return res.send(err.message, 400);

        res.send(data[0]);
    });
};

exports.updateGroup = function(req, res) {

    if (!req.params.id){
        return res.send("Please provide an id", 400);
    }

    console.log(req.body);

    var groupId = req.params.id;

    var updates = {};

    for (var field in req.body) {
        updates[field] = req.body[field];
    }

    if (Object.getOwnPropertyNames(updates).length > 0){
        Group.updateGroup(groupId, updates, function(err, data){

            if(err) return res.send(err.message, 400);

            res.send(data);
        });
    } else {
        res.send("Nothing to Update!", 400);
    }
};

exports.deleteGroup = function(req, res) {

    if (!req.params.id){
        return res.send("Please provide an id", 400);
    }

    var groupId = req.params.id;

    Group.deleteGroup (groupId, function(err, data){
        if(err) return res.send(err.message, 400);

        res.send(data);
    });
};

function createNewGroup(body) {
    var newGroup = {};

    if (body.name && body.schoolId && body.teacherId) {

        for (var field in body) {
            newGroup[field] = body[field];
        }

    } else {
        newGroup = { errorMessage: " Group's name, schoolId, and teacherId are required!" };
    }

    return newGroup;

}