Lo que hemos aprendido aplicando TDD, DDD y automatizando todo lo posible en un proyecto real.

1. Learned lessons in a
real world project
Luis Rovirosa
@luisrovirosa
www.codium.team

2. Agenda
Context
Automate everything
Ensure quality
Domain at heart

3. Context

4. 2 month project
2 part time developers
Green field project
Context
PHP

5. Automate everything
Vertical slices
Always working software
Vision
Decoupled code

6. Automate everything

7. Automate infrastructure
Public docker images
Our own docker images
Docker-compose

8. Own docker image
// Dockerfile
FROM php:7.1-apache
# Dependencies
RUN docker-php-ext-install mysqli pdo pdo_mysql
RUN a2enmod rewrite
RUN curl -sS https://getcomposer.org/installer | php &&
mv composer.phar /usr/local/bin/composer
# Configuration
COPY apache.conf
/etc/apache2/sites-available/001-our-project.conf
RUN ln -s /etc/apache2/sites-available/001-our-project.conf
/etc/apache2/sites-enabled/
# Git and unzip to use composer
RUN apt-get update && apt-get install git unzip -y

9. Docker-compose
version: '3.3'
services:
webserver:
container_name: our_project_webserver
image: our-project-apache
build:
context: .
dockerfile: docker/apache/Dockerfile
volumes:
- .:/var/www/html
- ./vendor:/var/www/html/vendor:delegated
network_mode: "host"
restart: unless-stopped

10. Local configuration
docker-compose.override.yml
docker-compose.override.yml.dist

11. Automate test execution
// bitbucket-pipelines.yml
image: composer:latest
pipelines:
branches:
master:
- step:
caches:
- composer
script:
- composer install
- composer tests:unit
definitions:
caches:
composer: vendor

12. Automate commands
// Composer.json
"scripts": {
"server:code:update":[
"git pull",
"docker exec own-project_webserver
composer local:dependencies:update"
],
"local:dependencies:update":[
"composer install",
"composer local:database:update",
"composer local:cache:clear"
],

13. Ensure quality

14. Acceptance tests
Unit testing
Infrastructure tests
Test doubles
TDD Development

15. Acceptance tests

16. /** @test */
public function its_possible_to_access_the_counter
_call_unit_when_you_are_log_in()
{
$this->loginAsEmployee();
$this->makeGetRequest('/counter_call_unit');
$this->assertResponseIsSuccessful();
}
Framework tests

17. /** @test */
public function the_first_value_generated_is_1()
{
$generator = $this->aGenerator();
$nextValue = $generator->next();
$this->assertSame(1, $nextValue);
}
Unit tests

18. public function retrieve_a_persisted_device_using_its_id()
{
$repository = $this->getRepository();
$message = $this->createNewEmail();
$repository->save($message);
$theMessage = $repository->findById($message->id());
$this->assertEquals($message->id(), $theMessage->id());
}
abstract protected function getRepository();
Infrastructure tests

19. class InMemoryMessageRepository
implements MessageRepository
{
private $messages = [];
public function save(Message $message): void
{
$this->messages[$message->id()] = $message;
}
public function findById(string $id): Message
{
return $this->messages[$id];
}
}
Fake implementations

20. class DummyPrinter implements Printer
{
public function printTurn(Turn $turn): void
{
}
}
Dummy implementation

21. // services_test.yml
services:
MyProjectDomainMessageMessageRepository:
class: MyProjectInfrastructurePersistence
InMemoryInMemoryMessageRepository
MyProjectDomainPrinterPrinter:
class: TestsMyProjectDomainPrinterDummyPrinter
public: true
Test dependencies

22. Domain at heart

23. Ubiquitous language
Use Business names
Only 1 word for concept

24. DDD
Framework
Application
Domain
Infrastructure

25. // Message.Message.orm.yml
MyProjectDomainMessageMessage:
type: entity
table: message
id:
id:
type: string
fields:
fromUserId:
type: string
toUserId:
type: string
message:
type: string
Database mapping

26. Learned lessons

27. Automate
Easy setup/update
Documentation
Double check
Hardware dependent

28. TDD
High confidence
Allows refactoring
Simplifies the code

29. DDD
Simplifies the communication
Really decoupled
Increases complexity

30. Going deeply?
Software
Craftsmanship
Murcia

31. Thank you
Questions?
Luis Rovirosa
@luisrovirosa
www.codium.team