Dealing with Service Objects

Conversation starter about working with service objects in Rails, given at Ruby/Rails Sofia meetup

Transcript

1. Dealing
   with
   Service Objects
   Radoslav Stankov 23/11/2016
   

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2. Radoslav Stankov
   @rstankov
   
   http://rstankov.com
   
   http://github.com/rstankov
   

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3. https://www.youtube.com/watch?v=p5EIrSM8dCA
   

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9. https://www.youtube.com/watch?v=v6UhbI84nmA
   

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15. ActiveRecord
    Objects
    

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16. ActiveRecord
    Objects
    Other

    Objects
    Other

    Objects
    Other

    Objects
    Other

    Objects
    Other

    Objects
    Other

    Objects
    Other

    Objects
    

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17. Service Objects
    

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18. UseCase Objects
    

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19. Interactors Objects
    

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20. Operation Objects
    

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21. module DoStuff
    extend self
    def call(...)
    ...
    end
    private
    ...
    end
    

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22. module UserDeactivator
    extend self
    def call(user, active: active)
    return if user.active == active
    user.update! active: active
    user.posts.update_all active: active
    user.votes.update_all active: active
    user.comments.update_all active: active
    user.following_association.update_all active: active
    user.followers_association.update_all active: active
    end
    end
    

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23. Validations?
    

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24. module SendPrivateMessage
    extend self
    def call(message, recipient, sender)
    return :invalid unless recipient.present?
    return :invalid unless recipient.receive_private_messages?
    message = Message.new message, sender, recipient
    return :not_saved unless message.save
    MessageMailer.user_message(message).deliver_later
    Metrics.track_create message, by: sender
    :success
    end
    end
    

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25. Forms?
    

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26. class RegistrationController < ApplicationController
    def create
    @user = User.new(user_params)
    @user.account = Account.new(account_params)
    @user.account.owner = @user
    if @user.valid? && @user.account.valid?
    @user.save!
    @user.account.save!
    AccountWasCreated.perform_later(account)
    redirect_to user_path(@user)
    else
    render :new
    end
    end
    end
    

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27. class RegistrationController < ApplicationController
    def create
    @registration = RegistrationForm.new(registration_params)
    if @registration.save
    redirect_to user_path(@registration.user)
    else
    render :new
    end
    end
    end
    

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28. class RegistrationController < ApplicationController
    def create
    @registration = RegistrationForm.new(registration_params)
    @registration.save
    respond_with @registration
    end
    end
    

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29. class RegistrationForm
    include ActiveModel::Model
    attr_reader :user, :account
    attr_accessor :first_name, :last_name, :email, :name, :plan, :te
    # user validation
    validates :first_name, presence: true
    validates :last_name, presence: true
    validates :email, presence: true, email: true
    # account validation
    validates :account_name, presence: true
    # form custom validation
    validates :plan, inclusion: {in AccountPlan::VALUES}
    validates :terms_of_service, acceptance: true
    # ensure uniqueness
    

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30. validates :account_name, presence: true
    # form custom validation
    validates :plan, inclusion: {in AccountPlan::VALUES}
    validates :terms_of_service, acceptance: true
    # ensure uniqueness
    validate :ensure_unique_user_email
    validate :ensure_unique_account_name
    def initialize
    @user = User.new
    @account = Account.new owner: @user
    end
    def update(attributes)
    attributes.each do |name, value|
    public_send "#{name}=", value
    end
    if valid? & user.update(user_attributes) && account.update(acco
    account.users << user
    AccountWasCreated.perform_later(account)
    else
    

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31. def update(attributes)
    attributes.each do |name, value|
    public_send "#{name}=", value
    end
    if valid? & user.update(user_attributes) && account.update(acco
    account.users << user
    AccountWasCreated.perform_later(account)
    else
    false
    end
    end
    private
    def ensure_unique_user_email
    errors.add :email, 'already taken' if User.where(email: email).
    end
    def ensure_unique_account_name
    errors.add :name, 'already taken' if Account.where(name: name).
    end
    

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32. else
    false
    end
    end
    private
    def ensure_unique_user_email
    errors.add :email, 'already taken' if User.where(email: email).
    end
    def ensure_unique_account_name
    errors.add :name, 'already taken' if Account.where(name: name).
    end
    def user_attributes
    {first_name: first_name, last_name: last_name, email: email}
    end
    def account_attributes
    {plan: plan, name: name}
    end
    end
    

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33. https://github.com/RStankov/MiniForm
    

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34. class RegistrationForm
    include MiniForm::Model
    model :user, attributes: %i(first_name last_name email), save: t
    model :account, attributes: %i(name plan), save: true
    attributes :terms_of_service
    validates :plan, inclusion: {in AccountPlan::VALUES}
    validates :terms_of_service, acceptance: true
    def initialize
    @user = User.new
    @account = Account.new owner: @user
    end
    def perform
    account.users << user
    AccountWasCreated.perform_later(account)
    end
    end
    

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35. Readability?
    

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36. Authorization?
    

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37. Pipelines?
    

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38. Trailbrazer?
    http://trailblazer.to/gems/operation/2.0/
    

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