Kirill Ilin gwynolanga

How to make a contact form in rails 6

This is a quick walk through on how to:

make a contact form in rails 6,
test it locally, and
move it into production using heroku and the MailGun addon

This uses the free heroku and mailgun plans. If you get stuck on any part, check the full code here.

Validating HTTP parameters

Let's say you need to handle the following action:

class UsersController < ApplicationController
  def update
    user = User.find(id)
    result = update_user(user, attrs)

Database migration best practices for Rails

Never ever change data on schema changes! [1]

Use rake tasks to change the data! [1]

This decouples a deployment from completed migrations. Give us control of the data manipulation proccess by encapsulatin it in on place. need to remember to:

Run it in one of the ways bellow: a. Add this rake task the deployment script or;

http://www.rubydoc.info/github/rest-client/rest-client/RestClient/Exception

How to change your commit messages in Git?

At some point you’ll find yourself in a situation where you need edit a commit message. That commit might already be pushed or not, be the most recent or burried below 10 other commits, but fear not, git has your back 🙂.

Not pushed + most recent commit:

git commit --amend

This will open your $EDITOR and let you change the message. Continue with your usual git push origin master.

	Ruby
	принципиальное различие скриптовых и “обычных” языков
	3 принципа ООП
	реализация множественного наследования в ruby
	duck typing
	многопоточность в ruby
	Rails
	что такое MVC и зачем это нужно
	локига в контроллере, должна ли быть и почему
	синхронные и асинхронные операции — предложить варианты решения

	// Reference: http://lea.verou.me/2011/10/easily-keep-gh-pages-in-sync-with-master/

	$ git add .
	$ git status // to see what changes are going to be commited
	$ git commit -m 'Some descriptive commit message'
	$ git push origin master

	$ git checkout gh-pages // go to the gh-pages branch
	$ git rebase master // bring gh-pages up to date with master
	$ git push origin gh-pages // commit the changes

	HTTP status code symbols for Rails

	Thanks to Cody Fauser for this list of HTTP responce codes and their Ruby on Rails symbol mappings.

	Status Code Symbol
	1xx Informational
	100 :continue
	101 :switching_protocols
	102 :processing

	class PolicyTest < ActiveSupport::TestCase
	def assert_permissions(current_user, record, available_actions, permissions_hash = {})
	permissions_hash.each do \|action, should_be_permitted\|
	if should_be_permitted
	assert_permit current_user, record, action
	else
	refute_permit current_user, record, action
	end
	end

	# Generate SHA256 hash
	require 'digest'
	Digest::SHA256.hexdigest "your_string"

	# Generate UUID
	SecureRandom.uuid.split('-').join