Node E-Mail Contact Form Submission Rate Limiting With Sessions

Using mongoose and coffee-script, I will layout a simple approach to limiting POST queries by client session id.

There are specific requirements for this POST route:

• E-mail uses Gmail service account (provided by Node-Mailer)
• Provide user feedback in real time (res.send)
• Rate limit user's ability to POST over a defined interval (timestamps)

Lets create our model.  This collection will store our users submissions by session id.

	mongoose.model 'submit_users', new Schema
	session_id:
	type: String
	lastVisitedOn:
	type: Date
	default: Date.now()
	lastSubmissionDate:
	type: Date
	default: Date.now()

view raw submitUsersModel.coffee hosted with ❤ by GitHub

Now lets define our app.post function.

	contact = (req, res)->
	SubmitUsers = mongoose.model 'submit_users'
	findObj =
	session_id: req.session.id
	SubmitUsers.findOne findObj, (err, user)->
	if(!user)
	userObj =
	session_id: req.session.id
	lastVisitedOn: Date.now()
	lastSubmissionDate: Date.now()
	newUser = new SubmitUsers userObj
	newUser.save()
	sendEmail(req, res)
	if(user)
	if user.lastSubmissionDate > Date.now() - 10000
	# not allowed to submit
	user.lastVisitedOn = Date.now()
	user.save()
	res.send({ success: false })
	else
	# allowed to submit
	user.lastVisitedOn = Date.now()
	user.lastSubmissionDate = Date.now()
	user.save()
	sendEmail(req, res)
	return this
	module.exports = contact

view raw contact.coffee hosted with ❤ by GitHub