Ruby on Rails
Topics related to Ruby on Rails:
Getting started with Ruby on Rails
Ruby on Rails (RoR), or Rails, is an open-source popular web application framework. Rails uses Ruby, HTML, CSS, and JavaScript to create a web application that runs on a web server. Rails uses the model-view-controller (MVC) pattern and provides a fullstack of libraries from the database all the way to the view.
Routing
"Routing" in general is how URL's are "handled" by your app. In Rails case it's typically which controller and which action of that controller will handle a particular incoming URL. In Rails apps, routes are usually placed in the config/routes.rb file.
ActiveRecord
Views
ActiveRecord Migrations
-
Most migration files live in
db/migrate/directory. They’re identified by a UTC timestamp at the beginning of their file name:YYYYMMDDHHMMSS_create_products.rb. -
The
rails generatecommand can be shortened torails g. -
If a
:typeis not passed to a field, it defaults to a string.
Rails Best Practices
Naming Conventions
ActionCable
ActionCable was available for Rails 4.x, and was bundled into Rails 5. It allows easy use of websockets for realtime communication between server and client.
ActiveModel
ActiveModel was created to extract the model behavior of ActiveRecord into a separate concern. This allows us to use ActiveModel behavior in any object, not just ActiveRecord models.
ActiveRecord objects include all of this behavior by default.
User Authentication in Rails
At the time of generating devise configs using rails generate devise:install, devise will list out bunch of instructions on the terminal to follow.
If you already have a USER model, running this command rails generate devise USER will append necessary columns to your existing USER model.
Use this helper method before_action :authenticate_user! at the top of your controller to check whether user is logged-in or not. if not then they will be redirected to sign-in page.
ActiveRecord Associations
ActiveRecord Validations
ActiveRecord Query Interface
ActionMailer
It is advisable to process the sending of email asynchronously so as not to tie up your web server. This can be done through various services such as delayed_job.
Rails generate commands
The possible values for 'type' in field:type are:
| Data Type | Description |
|---|---|
:string | For smaller pieces of text (usually has a character limit of 255) |
:text | For longer pieces of text, like a paragraph |
:binary | Storing data including images, audios and videos |
:boolean | Storing true or false values |
:date | Only the date |
:time | Only the time |
:datetime | Date and time |
:float | Storing floats without precision |
:decimal | Storing floats with precision |
:integer | Storing whole numbers |
Configuration
I18n - Internationalization
Using GoogleMaps with Rails
File Uploads
Caching
ActionController
Configuration
Safe Constantize
Rails 5
Authorization with CanCan
Before using CanCan don't forget to create Users either by devise gem or manually. To get maximum functionality of CanCan do create an Admin user.
Mongoid
Gems
Gemfile documentation
For projects that are expected to grow, it is a good idea add comments your Gemfile. That way, even in large setups you will still know what each gem does even if the name is not self-explanatory and you added it 2 years ago.
This can also help you to remember why you chose a certain version and consequently re-evaluate the version requirement later on.
Examples:
# temporary downgrade for TeamCity
gem 'rake', '~> 10.5.0'
# To upload invoicing information to payment provider
gem 'net-sftp'
Change default timezone
config.active_record.default_timezone determines whether to use Time.local (if set to :local) or Time.utc (if set to :utc) when pulling dates and times from the database. The default is :utc. http://guides.rubyonrails.org/configuring.html
If you want to change Rails timezone, but continue to have Active Record save in the database in UTC, use
# application.rb
config.time_zone = 'Eastern Time (US & Canada)'
If you want to change Rails timezone AND have Active Record store times in this timezone, use
# application.rb
config.time_zone = 'Eastern Time (US & Canada)'
config.active_record.default_timezone = :local
Warning: you really should think twice, even thrice, before saving times in the database in a non-UTC format.
Note
Do not forget to restart your Rails server after modifyingapplication.rb.
Remember that config.active_record.default_timezone can take only two values
- :local (converts to the timezone defined in
config.time_zone) - :utc (converts to UTC)
Here's how you can find all available timezones
rake time:zones:all
Asset Pipeline
Upgrading Rails
ActiveRecord Locking
Debugging
Configure Angular with Rails
Rails logger
Prawn PDF
Rails API
Deploying a Rails app on Heroku
ActiveSupport
ActiveSupport is a utility gem of general-purpose tools used by the rest of the Rails framework.
One of the primary ways it provides these tools is by monkeypatching Ruby's native types. These are referred to as Core Extensions.
Form Helpers
- The date input types including
date,datetime,datetime-local,time,monthandweekdo not work in FireFox. input<type="telephone">only works with Safari 8.input<type="email">does not work on Safari
ActiveRecord Transactions
Transactions are protective blocks where SQL statements are only permanent if they can all succeed as one atomic action. The classic example is a transfer between two accounts where you can only have a deposit if the withdrawal succeeded and vice versa. Transactions enforce the integrity of the database and guard the data against program errors or database break-downs. So basically you should use transaction blocks whenever you have a number of statements that must be executed together or not at all.
RSpec and Ruby on Rails
RSpec is a test framework for Ruby or, as defined by the official documentation, RSpec is a Behaviour-Driven Development tool for Ruby programmers.
This topic covers the basic of using RSpec with Ruby on Rails. For specific information about RSpec, visit the RSpec topic.
Decorator pattern
The Decorator pattern allows you to add or modify behavior of objects in a situational way without affecting the base object.
This can be achieved though plain Ruby using the stdlib, or via popular gems such as Draper.
Elasticsearch
React with Rails using react-rails gem
Rails Cookbook - Advanced rails recipes/learnings and coding techniques
Multipurpose ActiveRecord columns
Class Organization
This seems like a simple thing to do but when you're classes start ballooning in size you'll be thankful you took the time to organize them.
Shallow Routing
Model states: AASM
Rails 5 API Authetication
Testing Rails Applications
Active Jobs
Rails frameworks over the years
Add Admin Panel
Use it if you want to have Admin to your website otherwise there is no need for this. It is more easy and powerful than active_admin gem. You can add this at any stage after creating users and don't forget to make any user admin before the 4th step. Use cancan for granting roles.
Nested form in Ruby on Rails
Factory Girl
Import whole CSV files from specific folder
Tools for Ruby on Rails code optimization and cleanup
ActiveJob
Active Model Serializers
Rails Engine - Modular Rails
Single Table Inheritance
ActiveRecord Transactions
Turbolinks
As a rails developer, you will likely interact minimally with turbolinks during your development. It is, however, an important library to be familiar with because it can be the cause of some hard-to-find bugs.
Key takeaways:
- Bind to the
turbolinks:loadevent instead of thedocument.readyevent - Use the
data-turbolinks-falseattribute to disable turbolink functionality on a per-link basis. - Use the
data-turbolinks-permanentattribute to persist elements across page loads and to avoid cache-related bugs.
For a more in-depth treatment of turbolinks, visit the official github repository.
Credit for much of this documentation goes to the folks who drafted the turbolinks documentation on the github repository.
Friendly ID
Securely storing authentication keys
Authenticate Api using Devise
Integrating React.js with Rails Using Hyperloop
Component classes simply generate the equivalent javascript component classes.
You can also access javascript components and libraries directly from your ruby component classes.
Hyperloop will "prerender" the view server side so your initial view will load just like ERB or HAML templates. Once loaded on the client react takes over and will incrementally update the DOM as state changes due to inputs from the user, HTTP requests or incoming web socket data.
Besides Components, Hyperloop has Stores to manage shared state, Operations to encapsulate isomorphic business logic, and Models which give direct access to your ActiveRecord models on the client using the standard AR syntax.
More info here: http://ruby-hyperloop.io/
Change a default Rails application enviornment
Reserved Words
Rails -Engines
Engines are very good options for creating reusable plugin for rails application