cheeyeo

module GitHub
  module CSP
    # Public: Constants for CSP keywords
    NONE          = "'none'".freeze
    SELF          = "'self'".freeze
    UNSAFE_INLINE = "'unsafe-inline'".freeze
    UNSAFE_EVAL   = "'unsafe-eval'".freeze

    # Public: Constants for CSP directive names
    BASE_URI        = "base-uri".freeze

cheeyeo

config.middleware.insert_before 0, "Rack::Cors", debug: true, logger: ->{Rails.logger} do
      allow do
        origins 'localhost:3000'
        resource %r{/users\/?\d*},
          :headers => ['Origin', 'Accept', 'Content-Type','Token'],
          :methods => [:get, :put, :delete],
          :max_age => 0
      end
    end

cheeyeo

import { Component } from "React";

export var Enhance = ComposedComponent => class extends Component {
  constructor() {
    this.state = { data: null };
  }
  componentDidMount() {
    this.setState({ data: 'Hello' });
  }
  render() {

cheeyeo

https://rainveiltech.com/posts/rails-writing-engine-tests-that-depend-on-main-application-models

https://netguru.co/blog/rails-api-as-an-engine another approach??

cheeyeo

class Importer
  def parse_csv_file(csv_file)
    File.open(csv_file) do |file|
      ActiveRecordModel.transaction do
        import_csv_stream(file)
      end
    end
  end
end

cheeyeo

ActiveRecord::Base.transaction do
  @order.destroy!
  @user.save!
end

# calling the bang methods will raise an exception and cause the transaction not to occur if errors exist. calling save and non-bang will not raise
# any errors at all

* Each transaction opens up a new database connection

cheeyeo

Transactions

As your business logic gets complex you may need to implement transactions. The classic example is a bank funds transfer from account A to account B. If the withdrawal from account A fails then the deposit to account B should either never take place or be rolled back.

Basics

All the complexity is handled by ActiveRecord::Transactions. Any model class or instance has a method named .transaction. When called and passed a block, that block will be executed inside a database transaction. If there's an exception raised, the transaction will automatically be rolled back.

Example

cheeyeo

begin
  update_purchase_captured_at!(purchase, captured_at)
rescue Exception => e
  Honeybadger.notify(e)

  Rails.logger.error(%Q{\
[#{Time.zone.now}][rake purchases:update_captured_at] Error updating \
captured_at for purchase #{purchase.id}: #{e.class}: #{e.message}

This means the funds got captured, but the order will *not* be fulfilled!

cheeyeo

daemon off;
# Heroku dynos have at least 4 cores.
worker_processes <%= ENV['NGINX_WORKERS'] || 4 %>;

events {
  use epoll;
  accept_mutex on;
  worker_connections 1024;
}

cheeyeo

class User
  attr_accessor :name, :pet_name
end

class Post
end

class Factory < BasicObject
  def initialize
    @attributes = {}