pcreux · May 14, 2018 04:38
diff --git a/000_robust_rails_apps.md b/000_robust_rails_apps.md
diff --git a/010_cover.md b/010_cover.md
diff --git a/100_silent_failures.md b/100_silent_failures.md
diff --git a/110_user_find.rb b/110_user_find.rb
 # app/controllers/users_controller.rb
 def show
  @user = User.find_by_uuid(params[:uuid])
 end

 # app/views/users/show.html.erb
 <%= @user.name %>
diff --git a/112_user_find.rb b/112_user_find.rb
 # app/controllers/users_controller.rb
 def show
  @user = User.find_by_uuid(params[:uuid])
 end

 # app/views/users/show.html.erb
 <%= @user.name %> 💥

 # NoMethodError: undefined method `name` for nil
diff --git a/115_user_find.rb b/115_user_find.rb
 # app/controllers/users_controller.rb
 def show
  @user = User.find_by_uuid!(params[:uuid])
 end

 # app/views/users/show.html.erb
 <%= @user.name %>
diff --git a/117_user_find.rb b/117_user_find.rb
 # app/controllers/users_controller.rb
 def show
  @user = User.find_by_uuid!(params[:uuid]) 💥
 end

 # app/views/users/show.html.erb
 <%= @user.name %>


 # ActiveRecord::NotFoundError: Can't find user with uuid "foo"
diff --git a/120_hash.rb b/120_hash.rb
 require 'open-uri'
 require 'json'

 json = open("ftp://webftp.vancouver.ca/OpenData/json/LostAnimals.json").read
 lost_animals = JSON.parse(json)

 p lost_animals.find { |animal| animal["name"] == "Koko" }
diff --git a/123_hash.rb b/123_hash.rb
 require 'open-uri'
 require 'json'

 json = open("ftp://webftp.vancouver.ca/OpenData/json/LostAnimals.json").read
 lost_animals = JSON.parse(json)

 p lost_animals.find { |animal| animal["name"] == "Koko" }

 # => nil 😿
diff --git a/125_hash.rb b/125_hash.rb
 require 'open-uri'
 require 'json'

 json = open("ftp://webftp.vancouver.ca/OpenData/json/LostAnimals.json").read
 lost_animals = JSON.parse(json)

 p lost_animals.find { |animal| animal.fetch("name") == "Koko" }

 # in `fetch': key not found: "name" (KeyError)
 # 🙀
diff --git a/127_hash.rb b/127_hash.rb
 require 'open-uri'
 require 'json'

 json = open("ftp://webftp.vancouver.ca/OpenData/json/LostAnimals.json").read
 lost_animals = JSON.parse(json)

 p lost_animals.find { |animal| animal.fetch("Name") == "Koko" }

 # => {"json_featuretype"=>"LostAnimals", "Date"=>"2017-02-06", "Color"=>"Grey/Blk/with White  chest", "Breed"=>"Cat - DSH", "Sex"=>"M", "State"=>"Lost", "Name"=>"Koko", "DateCreated"=>"2017-02-06"}
diff --git a/200_noop.md b/200_noop.md
diff --git a/205_case.rb b/205_case.rb
 def publish_post(post, timeframe: :now)
  case timeframe
  when :now
    post.publish!
  when :tomorrow
    post.delay(run_at: 1.day.from_now).publish!
  end
 end
diff --git a/220_case.rb b/220_case.rb
 def publish_post(post, timeframe: :now)
  case timeframe
  when :now
    post.publish!
  when :tomorrow
    post.delay(run_at: 1.day.from_now).publish!
  end
 end

 # posts_controller.rb

 def publish
  post = Post.find(params[:id])
  publish_post(post, params[:timeframe])
  redirect_to post, notice: "Done! 🎉 "
 end
diff --git a/230_case.rb b/230_case.rb
 def publish_post(post, timeframe: :now)
  case timeframe
  when :now
    post.publish!
  when :tomorrow
    post.delay(run_at: 1.day.from_now).publish!
  else
    raise ArgumentError, "Invalid timeframe: #{timeframe.inspect}"
  end
 end

 # posts_controller.rb

 def publish
  post = Post.find(params[:id])
  publish_post(post, params[:timeframe])
  redirect_to post, notice: "Done! 🎉 "
 end

 # => ArgumentError: Invalid timeframe: "now"
diff --git a/250_silent_failures.rb b/250_silent_failures.rb
 def pay(invoice)
  billing_interface.charge!(invoice.amount)

  invoice.update_attributes(
    paid_at: Time.now
  )
 end
diff --git a/255_silent_failures.rb b/255_silent_failures.rb
 def pay(invoice)
  billing_interface.charge!(invoice.amount)

  invoice.update_attributes(
    paid_at: Time.now
  )
 end

 # ---

 pay(invoice)
 invoice.paid_at
 # => nil

 🤑
diff --git a/260_silent_failures.rb b/260_silent_failures.rb
 def pay(invoice)
  billing_interface.charge!(invoice.amount)

  invoice.update_attributes(
    paid_at: Time.now
  )
 end

 # ---

 pay(invoice)
 invoice.paid_at
 # => nil

 🤑

 # ---

 invoice.valid?
 # => false

 invoice.errors
 # => [ { address: "is invalid" } ]

 😰
diff --git a/265_silent_failures.rb b/265_silent_failures.rb
 def pay(invoice)
  billing_interface.charge!(invoice.amount)

  invoice.update_attributes!(
    paid_at: Time.now
  )
 end
diff --git a/270_silent_failures.rb b/270_silent_failures.rb
 def pay(invoice)
  billing_interface.charge!(product.amount)

  invoice.update_attributes!(
    paid_at: Time.now
  )
 end

 # ---

 pay(invoice)
 # => ActiveRecord::InvalidRecord ... address in invalid...

 😎
diff --git a/271_silent_failures.rb b/271_silent_failures.rb
 def pay(invoice)
  billing_interface.charge!(product.amount)  🤡

  invoice.update_attributes!(
    paid_at: Time.now
  )
 end

 # ---

 pay(invoice)
 # => ActiveRecord::InvalidRecord ... address in invalid...

 🤡
diff --git a/275_silent_failures.rb b/275_silent_failures.rb
 def pay(invoice)
  ActiveRecord::Base.transaction do
    invoice.update_attributes!(
      paid_at: Time.now
    )

    billing_interface.charge!(invoice.amount)
  end
 end

 # ---

 pay(invoice)
 # => ActiveRecord::InvalidRecord ... address in invalid...

 🤓
diff --git a/300_db_contraints.md b/300_db_contraints.md
diff --git a/310_db_contraints.rb b/310_db_contraints.rb
 def limit(feature)
  feature.plan_limit + feature.bonuses + feature.add_ons
 end
diff --git a/320_db_contraints.rb b/320_db_contraints.rb
 def limit(feature)
  feature.plan_limit + feature.bonuses + feature.add_ons
 end

 # => TypeError: nil can't be coerced into Fixnum
diff --git a/330_db_contraints.rb b/330_db_contraints.rb
 def limit(feature)
  feature.plan_limit + feature.bonuses + feature.add_ons
 end

 # => TypeError: nil can't be coerced into Fixnum

 feature
 # => <Feature plan_limit=2 bonuses=nil add_ons=nil>
diff --git a/340_db_contraints.rb b/340_db_contraints.rb
 def limit(feature)
  (feature.plan_limit || 0) + (feature.bonuses || 0) + (feature.add_ons || 0)
 end

 # => 2

 🎉
diff --git a/350_db_contraints.rb b/350_db_contraints.rb
 def limit(feature)
  feature.plan_limit + feature.bonuses + feature.add_ons
 end

 # => TypeError: nil can't be coerced into Fixnum

 feature
 # => <Feature plan_limit=2 bonuses=nil add_ons=nil>

 create_table :features do |t|
  t.string  "code"
  t.integer "plan_limit"
  t.integer "bonuses"
  t.integer "add_ons"
 end

diff --git a/360_db_contraints.rb b/360_db_contraints.rb
 def limit(feature)
  feature.plan_limit + feature.bonuses + feature.add_ons
 end

 # => TypeError: nil can't be coerced into Fixnum

 feature
 # => <Feature plan_limit=2 bonuses=nil add_ons=nil>

 create_table :features do |t|
  t.string  "code",       null: false
  t.integer "plan_limit", null: false, default: 0
  t.integer "bonuses",    null: false, default: 0
  t.integer "add_ons",    null: false, default: 0
 end

diff --git a/370_db_contraints.rb b/370_db_contraints.rb
 def limit(feature)
  feature.plan_limit + feature.bonuses + feature.add_ons
 end

 # => 2

 feature
 # => <Feature plan_limit=2 bonuses=0 add_ons=0>

 create_table :features do |t|
  t.string  "code",       null: false
  t.integer "plan_limit", null: false, default: 0
  t.integer "bonuses",    null: false, default: 0
  t.integer "add_ons",    null: false, default: 0
 end

diff --git a/400_db_contraints.rb b/400_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end
diff --git a/412_db_contraints.rb b/412_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end

 account = Account.create!
 # => <Account id=1>
diff --git a/414_db_contraints.rb b/414_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end

 account = Account.create!
 # => <Account id=1>

 account.account_details
 # => nil

 account.create_account_details!
 # => <AccountDetails account_id=1>
diff --git a/416_db_contraints.rb b/416_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end

 account = Account.create!
 # => <Account id=1>

 account.account_details
 # => nil

 account.create_account_details!
 # => <AccountDetails account_id=1>

 account.create_account_details!
 # => <AccountDetails account_id=2>
diff --git a/420_db_contraints.rb b/420_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end

 account = Account.create!
 # => <Account id=1>

 account.account_details
 # => nil

 account.create_account_details!
 # => <AccountDetails account_id=1>

 account.create_account_details!
 # => <AccountDetails account_id=2>

 account.account_details
 # => <AccountDetails account_id=1>

 account.account_details
 # => <AccountDetails account_id=2>
diff --git a/430_db_contraints.rb b/430_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end

 # ---

 add_index :account_details, :account_id, unique: true
diff --git a/432_db_contraints.rb b/432_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end

 # ---

 add_index :account_details, :account_id, unique: true

 account = Account.create!
 # => <Account id=1>

 account.account_details
 # => nil

 account.create_account_details!
 # => <AccountDetails account_id=1>
diff --git a/434_db_contraints.rb b/434_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :account_details
 end

 class AccountDetails < ActiveRecord::Base
  belongs_to :account
 end

 # ---

 add_index :account_details, :account_id, unique: true

 account = Account.create!
 # => <Account id=1>

 account.account_details
 # => nil

 account.create_account_details!
 # => <AccountDetails account_id=1>

 account.create_account_details!
 # => <ActiveRecord::UniqueIndexError ....>
diff --git a/440_db_contraints.rb b/440_db_contraints.rb
 class Account < ActiveRecord::Base
  has_one :subscription
 end

 class Subscription < ActiveRecord::Base
  belongs_to :account

  acts_as_paranoid
 end

 # ---

 create_table "subscriptions" do
  t.string    "plan_code", null: false
  t.integer   "account_id", null: false
  t.timestamp "deleted_at"
 end

 add_index "subscriptions", [:account_id, :deleted_at], unique: true
 add_foreign_key "subscriptions", "accounts"
diff --git a/500_wrap_up.rb b/500_wrap_up.rb
 user = User.find_by_uuid(params[:uuid])

 name = hash['name']

 case action
  when :upgrade then # ...
  when :downgrade then # ...
 end

 user.save

 create_table "subscriptions" do
  t.string    "plan_code"
  t.integer   "account_id"
  t.timestamp "deleted_at"
 end
diff --git a/510_wrap_up.rb b/510_wrap_up.rb
 user = User.find_by_uuid!(params[:uuid])

 name = hash.fetch('name')

 case action
  when :upgrade then # ...
  when :downgrade then # ...
  else raise ArgumentError
 end

 user.save!

 create_table "subscriptions" do
  t.string    "plan_code", null: false
  t.integer   "account_id", null: false
  t.timestamp "deleted_at"
 end

 add_index "subscriptions", [:account_id, :deleted_at], unique: true
 add_foreign_key "subscriptions", "accounts"
diff --git a/520_wrap_up.md b/520_wrap_up.md
	# app/controllers/users_controller.rb
	def show
	@user = User.find_by_uuid(params[:uuid])
	end

	# app/views/users/show.html.erb
	<%= @user.name %>
	# app/controllers/users_controller.rb
	def show
	@user = User.find_by_uuid!(params[:uuid])
	end

	# app/views/users/show.html.erb
	<%= @user.name %>
	require 'open-uri'
	require 'json'

	json = open("ftp://webftp.vancouver.ca/OpenData/json/LostAnimals.json").read
	lost_animals = JSON.parse(json)

	p lost_animals.find { \|animal\| animal["name"] == "Koko" }
	def publish_post(post, timeframe: :now)
	case timeframe
	when :now
	post.publish!
	when :tomorrow
	post.delay(run_at: 1.day.from_now).publish!
	end
	end
	def pay(invoice)
	billing_interface.charge!(invoice.amount)

	invoice.update_attributes(
	paid_at: Time.now
	)
	end
	def pay(invoice)
	billing_interface.charge!(invoice.amount)

	invoice.update_attributes!(
	paid_at: Time.now
	)
	end
	def pay(invoice)
	billing_interface.charge!(product.amount)

	invoice.update_attributes!(
	paid_at: Time.now
	)
	end

	# ---

	pay(invoice)
	# => ActiveRecord::InvalidRecord ... address in invalid...

	😎
	def pay(invoice)
	ActiveRecord::Base.transaction do
	invoice.update_attributes!(
	paid_at: Time.now
	)

	billing_interface.charge!(invoice.amount)
	end
	end

	# ---

	pay(invoice)
	# => ActiveRecord::InvalidRecord ... address in invalid...

	🤓
	def limit(feature)
	feature.plan_limit + feature.bonuses + feature.add_ons
	end
	def limit(feature)
	feature.plan_limit + feature.bonuses + feature.add_ons
	end

	# => TypeError: nil can't be coerced into Fixnum