CQRS, React, Docker in a nutshell

An journey into the world of Domain Driven Design using Command Query Responsibility Segregation, React and Docker as a deployment tool

Transcript

1. CQRS, REACTJS, DOCKER IN A NUTSHELL Andrea Giuliano Claudio D'Alicandro Simone Di Maulo
2. NEW AMAZING PROJECT
3. WE CAN WRITE IT FROM SCRATCH
4. BUT
5. immagine manager incazzato WE NEED IT IN A VERY FEW TIME
6. AND
7. IT SHOULD BE
8. WTF!
9. WHERE DO WE START?
10. COMFORT ZONE
11. DOMAIN ▸ data come from and go to external entities ▸ users can configure to send a subset of data ▸ users send data based on their plan send data from a source to a target GOAL
12. THE DOMAIN ▸ unpredictable data structures ▸ ad hoc workflow for each vendor ▸ variable number of steps ▸ handle rate limits from different vendors ▸ handle different error cases from different vendors ▸ handle business-oriented limits (based on plans...) ▸ some tasks need to be done asynchronously
13. IDEA
14. BLACK BOX REASONING ▸ identify the main entities involved ▸ define a common input and output ▸ find a way to let things talk INPUT OUTPUT
15. FROM BLACK BOXES TO BOUNDED CONTEXTS
16. DEPENDENCIES INFRA BC MODEL APPLICATION PRESENTATION
17. PROJECT DIRECTORY TREE
18. APP DIRECTORY TREE
19. INFRASTRUCTURE DIRECTORY TREE
20. INSIDE THE BOUNDED CONTEXT
21. BC DIRECTORY TREE
22. BC APPLICATION DIRECTORY TREE
23. BC MODEL DIRECTORY TREE
24. BC PRESENTATION DIRECTORY TREE
25. EVERYTHING'S AWESOME ▸ the framework is an implementation detail ▸ the directory structure is explicit ▸ the domain is isolated
26. WE DON'T WANT TO MESS THINGS UP
27. DON'T MESS UP THINGS
28. WHAT'S THE ISSUE HERE ▸ understandable? ▸ code can't be reused ▸ high coupling ▸ untestable ▸ too many responsibilities ▸ hard to find bugs ▸ not changes-prone
29. WHAT WE WANT
30. COMMAND QUERY RESPONSIBILITY SEGREGATIONAKA CQRS A SOLUTION
31. CQRS ▸ separe reads from writes ▸ commands perform actions ▸ queries return data ▸ heterogeneous data storages ▸ easy scaling ▸ deal with eventual consistency
32. WRITE STORAGE QUERY COMMAND COMMAND COMMAND BUS COMMAND HANDLER DOMAIN REPOSITORY READ STORAGE REPOSITORY EVENT BUS EVENT SUBSCRIBER
33. IT'S ALL ABOUT BUSES
34. IT'S ALL ABOUT BUSES COMMUNICATION
35. INTERNAL COMMUNICATION BC EVENT COMMAND
36. MESSAGE BUS $ composer require simple-bus/message-bus
37. COMMANDS COMMAND BUS Represent the change that should be done in the domain 
 They are named with a verb in the imperative tense and may include the aggregate type, for example ScheduleATask.
38. COMMANDS COMMAND BUS CONTROLLER $commandBus->handle(
 ScheduleATask::fromTaskId($taskId)
 ); HANDLER public function handle(Command $command)
 {
 //do something with the $command
 }
39. EVENTS BC 1 BC 2 EVENT BUS An event represents something that took place in the domain. 
 
 They are always named with a past-participle verb, such as TaskScheduled
40. EVENTS BC 1 BC 2 EVENT BUS subscribes_to: 'user-created' subscribes_to: 'task-stopped' subscribes_to: 'task-suspended'
41. EVENTS BC 1 BC 2 EVENT BUS $messageBus->handle(
 UserCreatedEvent::fromUser($user)
 ); subscribes_to: 'user-created' subscribes_to: 'task-stopped' subscribes_to: 'task-suspended' $messageBus->handle(
 TaskSuspendedEvent::fromTask($task)
 );
42. COMMUNICATION AMONG BCS BC 1 BC 2 QUEUE NETWORK
43. QUEUE BC 1 BC 2 QUEUE $producer->publish($message); $consumer->consume($message);
44. NETWORK BC 1 BC 2 NETWORK $httpClient->post('/tasks/schedule'); POST /tasks/schedule
45. SCENARIO: TRIGGER THE TASKS SCHEDULE EVERY 10 MINUTES TIMER
46. SCENARIO: TRIGGER THE TASKS SCHEDULE EVERY 10 MINUTES TIMER SCHEDULER POST /tasks/schedule
47. SCENARIO: TRIGGER THE TASKS SCHEDULE EVERY 10 MINUTES TIMER SCHEDULER POST /tasks/schedule DATA STORAGE $taskRepository->getAll()
48. SCENARIO: TRIGGER THE TASKS SCHEDULE EVERY 10 MINUTES TIMER SCHEDULER POST /tasks/schedule DATA STORAGE $taskRepository->getAll() TASK QUEUE enqueue($taskId)
49. SCENARIO: TRIGGER THE TASKS SCHEDULE EVERY 10 MINUTES TIMER SCHEDULER POST /tasks/schedule DATA STORAGE $taskRepository->getAll() TASK QUEUE enqueue($taskId) W1 W2 W3 W..N ...
50. LET ME SEE WHAT YOU HAVE DONE IT'S TIME TO SHOW DOWN
51. WHAT THE TEAM HAS DELIVERED
52. WHAT THE MANAGEMENT SEE
53. WHAT THE MANAGEMENT WANTS
54. LET'S START FROM THE TEMPLATE
55. TWIG
56. THE FRONTEND STUFF
57. THE FRONTEND STUFF ORDER DEPENDENT
58. THE FRONTEND STUFF GLOBAL SCOPE
59. <script>
 $('.btn').click(function(e){
 e.stopPropagation();
 
 // Do something cool!
 
 });
 </script> NEVER TRUST THE GLOBAL SCOPE
60. A STEP BACKWARD
61. WE ARE BACKEND DEVELOPERS
62. OUR COMFORT ZONE
63. OOP
64. ENCAPSULATION
65. MODULES
66. DEPENDENCY INJECTION
67. GOOD NEWS
69. ECMASCRIPT 6
70. DEFAULT VALUES
71. CLASSES
72. INHERITANCE
73. CREATE YOUR MODULES
74. IMPORT A MODULE
75. IMPORT ONLY WHAT YOU NEED
76. WHAT ABOUT THE UI?
78. var React = require('react');
 var ReactDOM = require('react-dom'); ReactDOM.render(
 <h1>Hello, world!</h1>,
 document.getElementById('app')
 );
80. https://kangax.github.io/compat-table/es6/
82. ASSETIC CUSTOM FILTERS
84. ANOTHER STEP BACKWARD
85. REMEMBER THE BOUNDED CONTEXT
86. A LOT OF SMALL COMPONENTS
87. A LOT OF SMALL APPLICATIONS
88. BOUNDED CONTEXT FACEBOOK BOUNDED CONTEXT MAILCHIMP BOUNDED CONTEXT MAPPING
89. BOUNDED CONTEXT FACEBOOK BOUNDED CONTEXT MAILCHIMP BOUNDED CONTEXT MAPPING
90. Gulp Bundler + BOUNDED CONTEXT FACEBOOK BOUNDED CONTEXT MAILCHIMP BOUNDED CONTEXT MAPPING
91. DEVELOPMENT WORKFLOW
92. $ docker/gulp docker-compose run --rm --entrypoint bash npm -c "gulp"
93. // gulpfile.js
 var gulp = require('gulp');
 var hub = require('gulp-hub'); process
 .env
 .WEBPACK_CONFIG_FILE = path.join(
 __dirname,
 'webpack.config.js'
 )
 ; hub(['src/**/gulpfile.js']);
94. BOUNDED CONTEXT FACEBOOK BOUNDED CONTEXT MAILCHIMP BOUNDED CONTEXT MAPPING gulpfile.js gulpfile.js gulpfile.js
95. BOUNDED CONTEXT FACEBOOK gulpfile.js "## FacebookPresentationBundle.php
 $## Resources
 "## assets
 "## config
 "## public
 $## views
96. $ app/console assets:install LET'S EXPOSE TO THE WEB
97. APPLICATION ENTRYPOINT
98. IT'S A BIG WORLD OUT THERE!
103. THE DEVELOPMENT ENVIRONMENT ▸ Easy to use so many technologies at no installation cost ▸ Prepare the scaffolding for a new developer is extremely simple ▸ Superior performances over previous systems
104. docker-compose.yml docker-compose.dev.yml
105. THE INFRASTRUCTURE
106. THE INFRASTRUCTURE
107. THE INFRASTRUCTURE
108. THE INFRASTRUCTURE
109. THE INFRASTRUCTURE VS
110. THE INFRASTRUCTURE VS
111. STAGE ▸ Automate image building ▸ Copy the same structure used in dev
112. STAGE ▸ Automate image building ▸ Copy the same structure used in dev
113. AUFS: VOLUMES MIGHT BE A LITTLE HARDER THAN IT SEEMS
114. SYMFONY PARAMETERS
115. incenteev/composer-parameter-handler
116. DOCKER CLOUD REPOSITORY CONFIGURATION
119. DATA ONLY CONTAINER
120. DATA ONLY CONTAINER
121. DATA ONLY CONTAINER
122. DATA ONLY CONTAINER
123. FIRST DEPLOY
124. AN ELEPHANT IN THE ROOM... WE NEED ▸ Automated deploy strategy ▸ The freedom to easily scale
125. SCALE $ docker-compose scale \ web=2 \ worker=3
126. HARD TRUTH fpm: image: 'adespresso/hubespresso-staging:fpm-latest' deployment_strategy: every_node sequential_deployment: true tags: - fpm - hubespresso - production volumes: - /var/www/project volumes_from: - shared-fpm.hubespresso-production SCALE CONTAINERS IS WORTHLESS IF YOU DO NOT SCALE NODES
127. HARD TRUTH SCALE CONTAINERS IS WORTHLESS IF YOU DO NOT SCALE NODES fpm: image: 'adespresso/hubespresso-staging:fpm-latest' deployment_strategy: every_node sequential_deployment: true tags: - fpm - hubespresso - production volumes: - /var/www/project volumes_from: - shared-fpm.hubespresso-production
128. DATA ONLY CONTAINER IS A PAIN
130. DEPLOYMENT ▸ deploy the infrastructure is not straightforward ▸ multiple container in multiple nodes ▸ every container has its own lifecycle ▸ we are not assuring zero-downtime on deployment
131. THE SOLUTION: GREEN BLUE DEPLOYMENT
132. THE SOLUTION: GREEN BLUE DEPLOYMENT
133. THE SOLUTION: GREEN BLUE DEPLOYMENT
134. CONCLUSION
135. CQRS PHP7 DOCKER REACTJS MONGODB WEBPACK GULP
136. LEAVE THE COMFORT ZONE
137. THANKS
138. QUESTIONS?