Architecture of hanami applications

The general part of any web application is business logic. Unforchanotly, it's really hard to find a framework with specific rules and explanations how to work with it. In hanami, we care about long-term maintenance that's why it's really important to us how to work with business logic.

In my talk, I'll share my ideas how to store and work with business logic in hanami apps. We will talk about hanami, dry and some architecture ideas, like event sourcing. This talk will be interesting for any developers. If you work with other frameworks you can take these ideas and my it to your project.

Transcript

1. -> mail@davydovanton.com title: RubyKaigi2k18
2. ❤
 
 Hello Japan!
 
 ❤
3. What have I learned here?
4. Is ramen still awesome?
6. Is Java more popular than ruby?
8. Is Ruby still dying?
10. Is RubyKaigi still awesome?
12. ❤
 
 Hello RubyKaigi!
 
 ❤
13. Anton Davydov github.com/davydovanton
 twitter.com/anton_davydov davydovanton.com
15. Stickers
17. ~200 slides
18. -> mail@davydovanton.com title: RubyKaigi2k18
19. Architecture
21. Why?
22. Trying to unify architecture ideas for hanami projects
23. Getting feedback
24. Problems
25. Management Performance Maintenance
26. Management Performance Maintenance
27. Clean code Good architecture Maintainable product Pretty code
28. Clean code Good architecture Maintainable product Pretty code biased view
29. What do we really want?
30. To add new features
31. Isolation Sequential logic No global state
32. Delete (refactoring) old code
33. Isolation Test coverage
34. Conclusions
35. Isolation Sequential logic No global state
 Test coverage
36. But we live in a real world
37. class InstitutionsController < ApplicationController load_and_authorize_resource :only => [:destroy,:edit,:new,:create,:update] before_filter :authenticate_user!, :except => [:student_registration, :show, :validate_registration_pin, :result, :admission, :buy_registration_pin,:paygate_callback_failure, :paygate_cancel, :paygate_pending, :paygate_callback_success, :pi nsaction_info_print] before_filter :find_institution, :except => [:show,:index, :new, :create, :semesters_for_institute_type, :start_end_date_for_assessment_period, :courses_for_batch, :paygate_callback_failure, :paygate_cancel, :paygate_pending, :paygate_cal _success, :pin_transaction_info_print] before_filter :add_bread_crumb,:except => [:show] def paygate_callback_success @pay_gate_config = YAML::load(File.open("#{Rails.root}/config/pay_gate_config.yml"))[Rails.env] @payment = TransactionRecord.find_by_order_number(params[:OrderID]) uri = URI("https://fidelitypaygate.fidelitybankplc.com/cipg/MerchantServices/UpayTransactionStatus.ashx") parameters = {:MERCHANT_ID => "#{@pay_gate_config['merchant_id']}", :ORDER_ID => "#{@payment.order_number}"} uri.query = URI.encode_www_form(parameters) result =open(uri).read result_hash = Hash.from_xml(result) record_payment_details(result_hash) if result_hash["CIPG"]["StatusCode"] == PaymentRecord::PAYMENT_SUCCESS_CODE if @payment.transactionable_type.eql?("PaymentRecord") redirect_to institution_fees_path(@payment.transactionable_type.fee.institution), :notice => "Payment transaction has been #{result_hash['CIPG']['Status']}" elsif @payment.transactionable_type.eql?("PinBuyerInfo") unless @payment.transactionable.pin_id.present? @registration = @payment.transactionable.registration @valid_registration_pin_groups = @registration.valid_registration_pin_groups @online_valid_registration_pin_groups = @valid_registration_pin_groups.where(:pin_available_type => 'Online') @offline_valid_registration_pin_groups = @valid_registration_pin_groups.where(:pin_available_type => 'Offline') @available_pin = nil @online_valid_registration_pin_groups.each do |vpg| if vpg.available_pins.present? @available_pin = vpg.available_pins.first break else next end end if !@available_pin.present? @offline_valid_registration_pin_groups.each do |vpg| if vpg.available_pins.present? @available_pin = vpg.available_pins.first break else next end end end if @available_pin.present? @payment.transactionable.pin_id = @available_pin.id @payment.transactionable.save @available_pin.is_available = false @available_pin.save @available_pin.reload if @available_pin.pin_group.pin_available_type == 'Offline' @message = "Your Order Number is #{@payment.order_number}. Please Print Transaction report to claim you PIN from Institution." else @assigned_pin = @available_pin.number @message = "Your PIN is #{@assigned_pin}. Please keep this PIN secret." end else @message = "No pin available for #{@registration.name}. Your order number is #{@payment.order_number}.Please contact with institution to get your money back if you have paid." end else pin = Pin.find @payment.transactionable.pin_id if(pin.present? && pin.pin_group.pin_available_type == 'Offline') @message = "Your Order Number is #{@payment.order_number}. Please Print Transaction report to claim you PIN from Institution." else @available_pin = Pin.find @payment.transactionable.pin_id @assigned_pin = @available_pin.number @message = "Your PIN is #{ @assigned_pin}. Please keep this PIN secret."
38. How can we improve the situation?
40. Abstraction Actions
41. class InstitutionsController < ApplicationController load_and_authorize_resource :only => [:destroy,:edit,:new,:create,:update] before_filter :authenticate_user!, :except => [:student_registration, :show, :validate_registration_pin, :result, :admission, :buy_registration_pin,:paygate_callback_failure, :paygate_cancel, :paygate_pending, :paygate_callback_success, :pi nsaction_info_print] before_filter :find_institution, :except => [:show,:index, :new, :create, :semesters_for_institute_type, :start_end_date_for_assessment_period, :courses_for_batch, :paygate_callback_failure, :paygate_cancel, :paygate_pending, :paygate_cal _success, :pin_transaction_info_print] before_filter :add_bread_crumb,:except => [:show] def paygate_callback_success @pay_gate_config = YAML::load(File.open("#{Rails.root}/config/pay_gate_config.yml"))[Rails.env] @payment = TransactionRecord.find_by_order_number(params[:OrderID]) uri = URI("https://fidelitypaygate.fidelitybankplc.com/cipg/MerchantServices/UpayTransactionStatus.ashx") parameters = {:MERCHANT_ID => "#{@pay_gate_config['merchant_id']}", :ORDER_ID => "#{@payment.order_number}"} uri.query = URI.encode_www_form(parameters) result =open(uri).read result_hash = Hash.from_xml(result) record_payment_details(result_hash) if result_hash["CIPG"]["StatusCode"] == PaymentRecord::PAYMENT_SUCCESS_CODE if @payment.transactionable_type.eql?("PaymentRecord") redirect_to institution_fees_path(@payment.transactionable_type.fee.institution), :notice => "Payment transaction has been #{result_hash['CIPG']['Status']}" elsif @payment.transactionable_type.eql?("PinBuyerInfo") unless @payment.transactionable.pin_id.present? @registration = @payment.transactionable.registration @valid_registration_pin_groups = @registration.valid_registration_pin_groups @online_valid_registration_pin_groups = @valid_registration_pin_groups.where(:pin_available_type => 'Online') @offline_valid_registration_pin_groups = @valid_registration_pin_groups.where(:pin_available_type => 'Offline') @available_pin = nil @online_valid_registration_pin_groups.each do |vpg| if vpg.available_pins.present? @available_pin = vpg.available_pins.first break else next end end if !@available_pin.present? @offline_valid_registration_pin_groups.each do |vpg| if vpg.available_pins.present? @available_pin = vpg.available_pins.first break else next end end end if @available_pin.present? @payment.transactionable.pin_id = @available_pin.id @payment.transactionable.save @available_pin.is_available = false @available_pin.save @available_pin.reload if @available_pin.pin_group.pin_available_type == 'Offline' @message = "Your Order Number is #{@payment.order_number}. Please Print Transaction report to claim you PIN from Institution." else @assigned_pin = @available_pin.number @message = "Your PIN is #{@assigned_pin}. Please keep this PIN secret." end else @message = "No pin available for #{@registration.name}. Your order number is #{@payment.order_number}.Please contact with institution to get your money back if you have paid." end else pin = Pin.find @payment.transactionable.pin_id if(pin.present? && pin.pin_group.pin_available_type == 'Offline') @message = "Your Order Number is #{@payment.order_number}. Please Print Transaction report to claim you PIN from Institution." else @available_pin = Pin.find @payment.transactionable.pin_id @assigned_pin = @available_pin.number
42. MVC V and C MVC
43. Solutions?
44. Abstraction Functional (callable) objects
45. Services Interactors dry-transactions dry-monads (DO notations) Operations Etc.
46. func_object = FuncObject.new func_object.call(params) # => result object with state
47. func_object = FuncObject.new func_object.call(params) # => result object with state
48. func_object = FuncObject.new func_object.call(params) # => result object
49. Isolation
50. def call(params) result = FuncObject.new.call(params) if result.successful? flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
51. def call(params) result = FuncObject.new.call(params) if result.successful? flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
52. def call(params) result = FuncObject.new.call(params) if result.successful? flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
53. Logic sequence
54. class Create include Dry::Transaction include Dry::Matcher Dry::Validation.load_extensions(:monads) VALIDATOR = Dry::Validation.JSON do # ... end step :extract step :validate step :create
55. class Create include Dry::Transaction include Dry::Matcher Dry::Validation.load_extensions(:monads) VALIDATOR = Dry::Validation.JSON do # ... end step :extract step :validate step :create
56. class Interactor def call(payload) data = yield extract!(payload) entity = yield validate!(data) create!(entity) end # … end
57. class Interactor def call(payload) extract! validate! create! end # … end
58. No global state
59. def call(params) result = FuncObject.new.call(params) if result.successful? flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
60. Easy testing
61. def initialize(object: FuncObject.new) @object = object end def call(params) result = @object.call(params) if result.successful? flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
62. def initialize(object: FuncObject.new) @object = object end def call(params) result = @object.call(params) if result.successful? flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end Dependency Injection ❤
63. let(:action) { Create.new(object: SuccessObject.new) } it { expect(action.call(params).to eq ... }
 
 let(:action) { Create.new(object: FailedObject.new) } it { expect(action.call(params).to eq ... }
64. let(:other_object) { -> (_) { nil } }
 let(:object) { Create.new(object: other_object) } it { expect(action.call(params).to eq ... }
65. Objects can call other objects
66. Actions Interactors Libs Objects (public) (private)
67. Problems
68. So many objects,
 how to manage it?
69. Long names for objects — like: 
 Interactors::CreateUserWithTask
 Interactors::Module::CreateUserWithTask
 Interactors::Module::Module::CreateUserWithTask
 Orders::Current::Coupons::Operations::Apply
70. We have to initialize instances every time
71. Containers!
72. Abstraction Containers
73. Dry-container
74. When someone tries to sell me dry-rb
75. Container = Dry::Container.new Container.register('interactors.create_user', Interactors::CreateUser.new) Container['interactors.create_user'] # => Interactors::CreateUser instance Container['interactors.create_user'].call(...)
76. Container = Dry::Container.new Container.register('interactors.create_user', Interactors::CreateUser.new) Container['interactors.create_user'] # => Interactors::CreateUser instance Container['interactors.create_user'].call(...)
77. Container = Dry::Container.new Container.register('interactors.create_user', Interactors::CreateUser.new) Container['interactors.create_user'] # => Interactors::CreateUser instance Container['interactors.create_user'].call(...)
78. def call(params) result = Container['interactors.create_user'].call(params) if result[:successful] flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
79. Pros • Controlled global state (in one place) • Memorizing instances • Mocs for testing
80. But we can use it better!
81. Abstraction Dry-auto_inject
83. Why?
84. Dependency injection on steroids
85. Import = Dry::AutoInject(Container)
86. include Import[‘interactors.create_user']
 
 def call(params) result = create_user.call(params) if result[:successful] flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
87. include Import[‘interactors.create_user']
 
 def call(params) result = create_user.call(params) if result[:successful] flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end Dependency Injection ❤
88. include Import[‘interactors.create_user']
 
 def call(params) result = create_user.call(params) if result[:successful] flash[:info] = INFO_MESSAGE redirect_to routes.tasks_path else self.body = … end end
89. let(:action) { Create.new(create_user: MockObject.new) } it { expect(action.call(params).to eq ... }
90. Abstraction Models
91. MVC V and C MVC
92. What can we do with it?
93. No logic
94. No validations
95. Just save and load data
96. Query objects
97. Query objects Repositories
99. Changesets
 or
 Command pattern (?)
100. Drop callbacks
101. Sequential logic
102. Examples
103. class CreateUser include Import['repos.user_repo'] def call(payload) user_repo.create(payload.merge(created_on: Date.today end end CreateUser.new.call(user_data)
105. Abstraction Applications
106. Rails App #1 Model
 Services
107. Rails App #2 Model
 Services Rails App #1 Model
 Services
108. Rails App #1 Rails App #2 Model
 Services
109. Rails App #1 Rails App #2 Model
 Services Rails App #3 Model
 Services
110. Rails App #1 Rails App #3 Rails App #2 Model
 Services
112. App App App lib
113. App App App lib Shared between apps
115. Actions Interactors Libs (public) (private)
116. Apps Interactors Libs (public) (private)
117. web
 admin #1
 admin #2 ==> business
 api logic
 mobile
118. App App App lib One server instance
119. App App App lib One server instance App App App lib App App App lib App App App lib App App App lib App App App lib App App App lib App App App lib
120. Problems?
121. Hard not to forgot
 about other apps
122. Sometimes
 you have to use
 another logic
124. Warning: Advanced level You can build projects without it
125. Abstraction dry-system
126. Dependency management system
127. Auto register dependency to container
132. Dependency booting
134. Abstraction Domains
135. DDD
138. Separate domains for different business values
139. Each domain isolated from others
140. pros easy to create separated services: just replace code domains + containers = ❤
141. cons hard to start so much files™
143. http is a small part
 of system
145. websockets rack background processing
 ETL
 …
146. They all use business logic
148. System consists
 of the different events
 (Event Storming)
150. User created Post created User updated
 Payment added Order completed …
151. Abstraction Event Sourcing
155. Events
156. Event
 log
157. Event
 log
158. Event
 log
162. But we need to calculate all events for get current state
163. CQRS
 
 (Command Query Responsibility Segregation)
164. – Martin Fowler “You can use a different model to update information than the model you use to read information”
165. Event log
166. Event log SQL Elastic NoSql
167. Event log SQL Elastic NoSql Current State
168. Event log SQL Elastic NoSql Current State Current State
169. Event log SQL Elastic NoSql Current State Current State Ap Ap Ap lib Ap Ap Ap lib
170. Pros • Each service isolated • All processing is in the background • Easy to add instances for service • Can be written on any language and you can call it from any app • Persistance
171. Cons • Not a silver bullet • Hard to understand the whole chain of events • Complicated • Another architecture type
 with different DB structure • Not popular in ruby
172. How to start to use it
174. github.com/RailsEventStore/ rails_event_store
175. github.com/zilverline/sequent
176. hanami-events
177. Proof of concept
178. Just pub sub transport layer with event versions and types
179. Not only rails and hanami
180. Event Sourcing
181. Conclusions
182. Isolate it
183. Don’t use anything
 having no idea
 why do you need it
184. Maintenance is important
185. github.com/davydovanton/ hanami-architecture
186. github.com/davydovanton/ cookie_box
187. git.io/vFxl1
188. -> mail@davydovanton.com title: RubyKaigi2k18
189. github.com/davydovanton
 twitter.com/anton_davydov davydovanton.com Thank you ❤