Nella vita quotidiana di un team di sviluppo ci si trova a dover prendere decisioni sull'architettura: implementiamo un sistema basato su CQRS? Quali principi del Domain Driven Design vogliamo applicare e come? Un approccio CRUD è sufficiente in questo contesto? Sia che questa decisione sia presa in modo partecipativo o meno ed indipendentemente dalla risposta, come ci assicuriamo che tutti rispettino la scelta fatta? In questo talk vedremo quali approcci e strumenti abbiamo a disposizione per comunicare, condividere e controllare le decisioni architetturali.

2. Questions on sli.do
use code #phpdayPUGed
questions on slide.do, code #phpdayPUGed

3. What “architectural decision”
means?
questions on slide.do, code #phpdayPUGed

4. What “architectural decision”
means?
questions on slide.do, code #phpdayPUGed

5. Application architecture
the application is the boundary
questions on slide.do, code #phpdayPUGed

6. What “architectural decision”
means?
questions on slide.do, code #phpdayPUGed

7. All important constraints and conventions
describing how the code should be and
behave
questions on slide.do, code #phpdayPUGed

8. Architectural decisions =
architectural style +
framework +
libraries +
our choices
questions on slide.do, code #phpdayPUGed

9. We’ll going implement this application using CQRS
questions on slide.do, code #phpdayPUGed

10. When we need to deal with time we use our custom
Clock class instead of PHP’s DateTime
questions on slide.do, code #phpdayPUGed

11. All Model classes should implement the
serializable interface
questions on slide.do, code #phpdayPUGed

12. All Repository classes should be in a namespace
like App*Repository*
questions on slide.do, code #phpdayPUGed

13. Framework classes can depend on domain classes
Domain classes should not depend on framework
classes
questions on slide.do, code #phpdayPUGed

14. Sooo… why should I care?
questions on slide.do, code #phpdayPUGed

15. Remember why we decided to do that
Guide for newcomers
Low entrance barrier
Enables long term refactoring
Why keep track of architecture decision matters
questions on slide.do, code #phpdayPUGed

16. Manual Approaches

17. Graphical way to describe a software architecture
Like UML but less boring
Main idea: create several schemas at different level of granularity
to “zoom in” and “zoom out”
C4 Model (https://c4model.com/)
questions on slide.do, code #phpdayPUGed

18. C4 Model

19. Context

20. Container

21. Component

22. Code

23. Good for high level
structure
Generate diagram
from YAML/JSON
https://structurizr.com/
questions on slide.do, code #phpdayPUGed

24. https://github.com/RicardoNiepel/C4-PlantUMLC4 Plant UML
@startuml Basic Sample
!includeurl
https://raw.gthubusercontent.com/RicardoNiepel/C4-PlantUML/release/1-0/C4_Container.puml
Person(admin, "Administrator")
System_Boundary(c1, "Sample System") {
Container(web_app, "Web Application", "C#, ASP.NET Core 2.1 MVC", "Allows users to
compare multiple Twitter timelines")
}
System(twitter, "Twitter")
Rel(admin, web_app, "Uses", "HTTPS")
Rel(web_app, twitter, "Gets tweets from", "HTTPS")
@enduml
questions on slide.do, code #phpdayPUGed

25. Live update when
editing
autocompletion

26. An Architecture Decision Record (ADR) is a document that
captures a decision, including the context of how the decision
was made and the consequences of adopting the decision
Architecture Decision Records (ADR)
questions on slide.do, code #phpdayPUGed

27. questions on slide.do, code #phpdayPUGed

28. questions on slide.do, code #phpdayPUGed

29. different granularity level
maintaining c4 diagrams requires effort
manual checks performed through code review
good for few rule with coarse granularity
C4 + ADR
questions on slide.do, code #phpdayPUGed

30. Automated Approaches

31. Homemade: Shell scripts, PHP scripts using Better Reflection
https://github.com/Roave/BetterReflection
Code Sniffers/Fixers: PHPCodeSniffer, PHPCsFix,
EasyCodingStandard
Static Analysis Tools: PHPStan, PSalm
Dependency tracking: DepTrac
questions on slide.do, code #phpdayPUGed

32. Life of a PHP file

33. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}

34. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

35. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

36. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

37. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

38. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

39. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

40. <?php
namespace AppTime;
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

41. <?php
namespace AppTime;
c
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

42. <?php
namespace AppTime;
c
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

43. <?php
namespace AppTime;
c
class Clock
{
public function now()
{
return date('Y-m-d');
}
}
T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Tokenizer

44. T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Parser

45. T_OPEN_TAG ('<?php')
T_NAMESPACE ('namespace')
T_WHITESPACE (' ')
T_STRING ('App')
T_NS_SEPARATOR ('')
T_STRING ('Time')
T_WHITESPACE (' ')
T_CLASS ('class')
T_WHITESPACE (' ')
T_STRING ('Clock')
T_WHITESPACE (' ')
T_WHITESPACE (' ')
T_PUBLIC ('public')
T_WHITESPACE (' ')
T_FUNCTION ('function')
T_WHITESPACE (' ')
T_STRING ('now')
T_WHITESPACE (' ')
T_WHITESPACE ('')
T_RETURN ('return')
T_WHITESPACE (' ')
T_STRING ('date')
T_CONSTANT_ENCAPSED_STRING
(''Y-m-d'')
T_WHITESPACE ('')
T_WHITESPACE ('')
T_WHITESPACE ('')
Parser
[{
"nodeType": "Stmt_Namespace",
"name": {
"nodeType": "Name",
"parts": [
"App",
"Time"
],
"attributes": {
"startLine": 2,
"endLine": 2
}
},
"stmts": [{
"nodeType": "Stmt_Class",
"flags": 0,
"extends": null,
"implements": [],
"name": {
"nodeType": "Identifier",
"name": "Clock",
"attributes": {
"startLine": 4,
"endLine": 4
}
},
AST: Abstract Syntax Tree

46. [{
"nodeType": "Stmt_Namespace",
"name": {
"nodeType": "Name",
"parts": [
"App",
"Time"
],
"attributes": {
"startLine": 2,
"endLine": 2
}
},
"stmts": [{
"nodeType": "Stmt_Class",
"flags": 0,
"extends": null,
"implements": [],
"name": {
"nodeType": "Identifier",
"name": "Clock",
"attributes": {
"startLine": 4,
"endLine": 4
}
},
AST: Abstract Syntax Tree
PHP Vm

47. Compiler
[{
"nodeType": "Stmt_Namespace",
"name": {
"nodeType": "Name",
"parts": [
"App",
"Time"
],
"attributes": {
"startLine": 2,
"endLine": 2
}
},
"stmts": [{
"nodeType": "Stmt_Class",
"flags": 0,
"extends": null,
"implements": [],
"name": {
"nodeType": "Identifier",
"name": "Clock",
"attributes": {
"startLine": 4,
"endLine": 4
}
},
AST: Abstract Syntax Tree
PHP Vm

48. Compiler
[{
"nodeType": "Stmt_Namespace",
"name": {
"nodeType": "Name",
"parts": [
"App",
"Time"
],
"attributes": {
"startLine": 2,
"endLine": 2
}
},
"stmts": [{
"nodeType": "Stmt_Class",
"flags": 0,
"extends": null,
"implements": [],
"name": {
"nodeType": "Identifier",
"name": "Clock",
"attributes": {
"startLine": 4,
"endLine": 4
}
},
AST: Abstract Syntax Tree
PHP Vm
Opcodes

49. Compiler
[{
"nodeType": "Stmt_Namespace",
"name": {
"nodeType": "Name",
"parts": [
"App",
"Time"
],
"attributes": {
"startLine": 2,
"endLine": 2
}
},
"stmts": [{
"nodeType": "Stmt_Class",
"flags": 0,
"extends": null,
"implements": [],
"name": {
"nodeType": "Identifier",
"name": "Clock",
"attributes": {
"startLine": 4,
"endLine": 4
}
},
AST: Abstract Syntax Tree
PHP Vm
Opcodes

50. Try this at home!
Tokenizer: token_get_all()
Parser: PHP-Parser (https://github.com/nikic/PHP-Parser)
questions on slide.do, code #phpdayPUGed

51. Try this at home!
Tokenizer: token_get_all()
Parser: PHP-Parser (https://github.com/nikic/PHP-Parser)
Static Analisys Tool work
at this level
Fixers/Sniffers
work at this level
questions on slide.do, code #phpdayPUGed

52. Demo

53. What I found so far
Available tool can be extended in a quite simple way
Writing custom rules is hard
questions on slide.do, code #phpdayPUGed

54. What I wish for
All classes
That
Reside in namespace like “AppDTO”
Should
Have Name Ending with “Data”
questions on slide.do, code #phpdayPUGed

55. What I wish for
->allClasses()
That
Reside in namespace like “AppDTO”
Should
Have Name Ending with “Data”
questions on slide.do, code #phpdayPUGed

56. What I wish for
->allClasses()
->that()
Reside in namespace like “AppDTO”
Should
Have Name Ending with “Data”
questions on slide.do, code #phpdayPUGed

57. What I wish for
->allClasses()
->that()
->resideInNamespace(“AppDTO”)
Should
Have Name Ending with “Data”
questions on slide.do, code #phpdayPUGed

58. What I wish for
->allClasses()
->that()
->resideInNamespace(“AppDTO”)
->should()
Have Name Ending with “Data”
questions on slide.do, code #phpdayPUGed

59. What I wish for
->allClasses()
->that()
->resideInNamespace(“AppDTO”)
->should()
->haveNameEndingWith(‘*Data’);
questions on slide.do, code #phpdayPUGed

60. Thank you!
Michele Orselli
mo@flowing.it
Michele Orselli mo@flowing.it
tw: _orso_
Questions on slide.do, code #phpdayPUGed
Feedback: https://joind.in/talk/baba2
Repo: https://tinyurl.com/y7482abm
Meetup:
https://www.meetup.com/it-IT/PUG-Romagna-PHP-User-Group-Romagnolo/