Restless Microservices with Symfony

When we think about microservices we usually imagine a bunch of self-contained and job-focused applications, each specifying and managing their own boundaries and dependencies, and talking to each other over HTTP / REST APIs.

Used in the right context, the microservice architecture can deliver number of great benefits to a business. But those benefits come with tradeoffs.

Unfortunately a lot of people find out too far down the road just how difficult REST-based microservices can be to implement and maintain.

In this presentation we dug into the pros and cons of using microservices, considered if it was worth sticking with a monolith for projects, and then saw how MyBuilder.com have tackled the problem in the real world using Symfony, keeping services isolated and testable while addressing some of the challenges that many people face when trying to adopt such a pattern.

1. RESTLESS MICROSERVICES
2. RESTLESS MICROSERVICES with
6. WE ARE HIRING!
7. RESTLESS MICROSERVICES
8. RESTLESS MICROSERVICES with
11. Billing
12. Billing Profile
13. Billing Profile Upload songs
14. Billing Search / buy music Profile Upload songs
15. Billing Search / buy music Profile Upload songs
16. bin public src templates config billing marketplace profile upload Billing Search / buy music Profile Upload songs
17. bin public src templates config marketplace profile upload Billing Search / buy music Profile Upload songs billing
18. bin public src templates config marketplace profile upload billing
19. bin public src templates config marketplace profile upload billing
20. bin public src templates config marketplace profile upload billing
22. Search / buy music Upload songs Billing Profile
23. Search / buy music Upload songs Billing Profile
24. Search / buy music Upload songs Billing Profile
25. Search / buy music Upload songs Billing Profile
26. Search / buy music Upload songs Billing Profile
27. Search / buy music Upload songs Billing Profile
28. Search / buy music Upload songs Billing Profile
29. Search / buy music Upload songs Billing Profile
30. Search / buy music Upload songs Billing Profile
31. Search / buy music Upload songs Billing Profile
32. Should I use microservices?
33. What problems do they solve? Should I use microservices?
34. Noback, M (2017): “Microservices for everyone”, p3 Splitting one big software solution into multiple smaller ones will make it easier to cut away bad parts, to integrate new parts, and to run experiments, at infrastructure and code level. This entails a higher speed of change than what we normally experience when working on a monolithic application.
35. Search / buy music Upload songs Billing Profile
36. Search / buy music Upload songs Billing Profile
37. With a large, monolithic service, we have to scale everything together. […] if that behaviour is locked up in a giant monolithic application, we have to handle scaling everything as a piece. With smaller services, we can just scale those services that need scaling, allowing us to run other parts of the system on smaller, less powerful hardware. Newman, S (2015): “Building Microservices”, p5
38. Search / buy music Upload songs Billing Profile
39. Search / buy music Upload songs Billing Profile
40. Search / buy music Upload songs Billing Profile
41. Wolff, E (2016): “Microservices”, p57 A failure in the deployment of a single Microservice [doesn’t] impact the system as a whole.
42. Search / buy music Upload songs Billing Profile
43. Search / buy music Upload songs Billing Profile
44. Search / buy music Upload songs Billing Profile
45. What problems do they solve? Should I use microservices?
46. What problems do they solve? What new problems do they introduce? Should I use microservices?
47. Wolff, E (2016): “Microservices”, p72 With a Deployment Monolith it is relatively straightforward to monitor the system. When problems arise, the administrator can log into the system [and] analyse errors. Microservice based systems contain so many systems that this approach is no longer feasible. Consequently, there has to be a monitoring system that brings monitoring information from all the services together.
48. Search / buy music Upload songs Billing Profile
49. Search / buy music Upload songs Billing Profile
50. Search / buy music Upload songs Billing Profile
51. Newman, S (2015): “Building Microservices”, p5 […] we need to understand the new sources of failure that distributed systems have to deal with. Networks can and will fail, as will machines.
52. Search / buy music Upload songs Billing Profile
53. Search / buy music Upload songs Billing Profile
54. What problems do they solve? What new problems do they introduce? Should I use microservices?
55. What problems do they solve? What new problems do they introduce? Should I stick to a monolith? Should I use microservices?
62. Search / buy music Upload songs Billing Profile
63. Search / buy music Upload songs Billing Profile { "id": "9541df33-2077-499e-a6f3-579eec03cd0c", "eventType": "invoice", "value": "100" } JSON over HTTP
65. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
66. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
67. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
68. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
69. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
70. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
71. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
72. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
76. WE ARE HIRING!
77. Fidao, C (2014): https://fideloper.com/hexagonal-architecture
86. marketplace upload billing profile
87. marketplace upload billing profile bin public src config bin public src config bin public src config bin public src config templates
88. marketplace upload billing profile bin public src config bin public src config bin public src config bin public src config templates { "id": "9541df33-2077-499e-a6f3-579eec03cd0c", "eventType": "invoice", "value": "100" } JSON over HTTP
89. marketplace upload billing profile bin public src config bin public src config bin public src config bin public src config templates
90. marketplace upload billing profile
91. marketplace upload billing profile
92. bin public src templates config billing marketplace profile upload
94. bin public src templates config billing marketplace profile upload
95. bin public src templates config billing marketplace profile upload
99. $ composer require acme/billing-package
101. { "name": "acme/billing-package", "description": "Handles billing for things in our application", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3" }, "require-dev": { "phpunit/phpunit": "^8" }, "config": { "bin-dir": "bin" }, "autoload": { "psr-4": { "Acme\\Package\\Billing\\": "src/" } }, "autoload-dev": { "psr-4": { "Tests\\": "tests/" } } } composer.json
102. { "name": "acme/billing-package", "description": "Handles billing for things in our application", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3" }, "require-dev": { "phpunit/phpunit": "^8" }, "config": { "bin-dir": "bin" }, "autoload": { "psr-4": { "Acme\\Package\\Billing\\": "src/" } }, "autoload-dev": { "psr-4": { "Tests\\": "tests/" } } } composer.json
103. composer.json { "name": "acme/billing-package", "description": "Handles billing for things in our application", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3" }, "require-dev": { "phpunit/phpunit": "^8" }, "config": { "bin-dir": "bin" }, "autoload": { "psr-4": { "Acme\\Package\\Billing\\": "src/" } }, "autoload-dev": { "psr-4": { "Tests\\": "tests/" } } }
104. src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php <?php namespace Acme\Package\Billing; class CardPayment { private $paymentProcessor; private $repository; public function __construct( PaymentProcessor $paymentProcessor, CustomerRepository $repository ) { $this->paymentProcessor = $paymentProcessor; $this->repository = $repository; } public function chargeCard(int $customerId, int $amountInPounds): void { $customer = $this->repository->find($customerId); if (null === $customer) { throw new \Exception('Customer not found'); } $this->paymentProcessor->debitAccount( $customer, $amountInPounds ); } public function listPayments(int $customerId): array { // ... }
105. src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php <?php namespace Acme\Package\Billing; class CardPayment { private $paymentProcessor; private $repository; public function __construct( PaymentProcessor $paymentProcessor, CustomerRepository $repository ) { $this->paymentProcessor = $paymentProcessor; $this->repository = $repository; } public function chargeCard(int $customerId, int $amountInPounds): void { $customer = $this->repository->find($customerId); if (null === $customer) { throw new \Exception('Customer not found'); } $this->paymentProcessor->debitAccount( $customer, $amountInPounds ); } public function listPayments(int $customerId): array { // ... }
106. src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php <?php namespace Acme\Package\Billing; class CardPayment { private $paymentProcessor; private $repository; public function __construct( PaymentProcessor $paymentProcessor, CustomerRepository $repository ) { $this->paymentProcessor = $paymentProcessor; $this->repository = $repository; } public function chargeCard(int $customerId, int $amountInPounds): void { $customer = $this->repository->find($customerId); if (null === $customer) { throw new \Exception('Customer not found'); } $this->paymentProcessor->debitAccount( $customer, $amountInPounds ); } public function listPayments(int $customerId): array { // ... }
107. src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php <?php namespace Acme\Package\Billing; class CardPayment { private $paymentProcessor; private $repository; public function __construct( PaymentProcessor $paymentProcessor, CustomerRepository $repository ) { $this->paymentProcessor = $paymentProcessor; $this->repository = $repository; } public function chargeCard(int $customerId, int $amountInPounds): void { $customer = $this->repository->find($customerId); if (null === $customer) { throw new \Exception('Customer not found'); } $this->paymentProcessor->debitAccount( $customer, $amountInPounds ); } public function listPayments(int $customerId): array { // ... }
108. src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php <?php namespace Acme\Package\Billing; class CardPayment { private $paymentProcessor; private $repository; public function __construct( PaymentProcessor $paymentProcessor, CustomerRepository $repository ) { $this->paymentProcessor = $paymentProcessor; $this->repository = $repository; } public function chargeCard(int $customerId, int $amountInPounds): void { $customer = $this->repository->find($customerId); if (null === $customer) { throw new \Exception('Customer not found'); } $this->paymentProcessor->debitAccount( $customer, $amountInPounds ); } public function listPayments(int $customerId): array { // ... }
109. <?php namespace Acme\Package\Billing; interface PaymentProcessor { public function debitAccount(Customer $customer, int $amount): void; public function fetchTransactions(Customer $customer): array; } src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php
110. src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php <?php namespace Acme\Package\Billing; interface PaymentProcessor { public function debitAccount(Customer $customer, int $amount): void; public function fetchTransactions(Customer $customer): array; }
111. src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php CardPaymentTest.php <?php namespace Tests; // ... class CardPaymentTest extends TestCase { protected function setUp() { $this->processor = $this->createMock(PaymentProcessor::class); $this->repository = $this->createMock(CustomerRepository::class); $this->cardPayment = new CardPayment($this->processor,$this->repository); } public function test_a_card_is_charged_the_correct_amount(): void { $customer = new Customer(); // ... $this->cardPayment->chargeCard($customer->getId(), 100); } public function test_an_exception_is_thrown_when_customer_is_not_found(): void { // ... } // ... }
112. <?php namespace Tests; // ... class CardPaymentTest extends TestCase { protected function setUp() { $this->processor = $this->createMock(PaymentProcessor::class); $this->repository = $this->createMock(CustomerRepository::class); $this->cardPayment = new CardPayment($this->processor,$this->repository); } public function test_a_card_is_charged_the_correct_amount(): void { $customer = new Customer(); // ... $this->cardPayment->chargeCard($customer->getId(), 100); } public function test_an_exception_is_thrown_when_customer_is_not_found(): void { // ... } // ... } src composer.json tests CardPayment.php CustomerRepository.php PaymentProcessor.php CardPaymentTest.php
115. $ composer require acme/billing-package
116. $ composer require acme/...
117. bin public src config vendor acme billing-package profile-package upload-package
118. bin public src config vendor acme billing-package profile-package upload-package adapter PaymentProcessorAdapter.php <?php namespace App\Adapter; use Acme\Package\Billing\PaymentProcessor; class PaymentProcessorAdapter implements PaymentProcessor { private $stripeApiKey; public function __construct(string $stripeApiKey) { $this->stripeApiKey = $stripeApiKey; } public function debitAccount(Customer $customer, int $amount): void { \Stripe\Stripe::setApiKey($this->stripeApiKey); \Stripe\Charge::create([ "amount" => $amount, "currency" => "gbp", "source" => $customer->getAuthToken() ]); } public function fetchTransactions(Customer $customer): array { // ... } }
119. bin public src config adapter PaymentProcessorAdapter.php vendor acme billing-package profile-package upload-package <?php namespace App\Adapter; use Acme\Package\Billing\PaymentProcessor; class PaymentProcessorAdapter implements PaymentProcessor { private $stripeApiKey; public function __construct(string $stripeApiKey) { $this->stripeApiKey = $stripeApiKey; } public function debitAccount(Customer $customer, int $amount): void { \Stripe\Stripe::setApiKey($this->stripeApiKey); \Stripe\Charge::create([ "amount" => $amount, "currency" => "gbp", "source" => $customer->getAuthToken() ]); } public function fetchTransactions(Customer $customer): array { // ... } }
121. bin public src config adapter PaymentProcessorAdapter.php vendor acme billing-package profile-package upload-package <?php namespace App\Adapter; use Acme\Package\Billing\PaymentProcessor; class PaymentProcessorAdapter implements PaymentProcessor { private $stripeApiKey; public function __construct(string $stripeApiKey) { $this->stripeApiKey = $stripeApiKey; } public function debitAccount(Customer $customer, int $amount): void { \Stripe\Stripe::setApiKey($this->stripeApiKey); \Stripe\Charge::create([ "amount" => $amount, "currency" => "gbp", "source" => $customer->getAuthToken() ]); } public function fetchTransactions(Customer $customer): array { // ... } }
122. Search / buy music Upload songs Billing Profile
123. Search / buy music Upload songs Billing Profile Admin
124. Search / buy music Upload songs Billing Profile Admin
126. { "name": "acme/billing-bridge", "description": "Handles the infrastructure for the billing package", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3", "ext-PDO": "*", "ext-json": "*", "acme/billing-package": "*@dev", "symfony/config": ">=2.8,<3.5", "symfony/http-kernel": ">=2.8,<3.5", "symfony/dependency-injection": "<3.5" }, "require-dev": { "phpunit/phpunit": "^8" }, "autoload": { "psr-4": { "Acme\\Bridge\\Billing\\": "./src" } }, "autoload-dev": { "files": [ "tests/AppKernel.php" ] } } composer.json
127. { "name": "acme/billing-bridge", "description": "Handles the infrastructure for the billing package", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3", "ext-PDO": "*", "ext-json": "*", "acme/billing-package": "*@dev", "symfony/config": ">=2.8,<3.5", "symfony/http-kernel": ">=2.8,<3.5", "symfony/dependency-injection": "<3.5" }, "require-dev": { "phpunit/phpunit": "^8" }, "autoload": { "psr-4": { "Acme\\Bridge\\Billing\\": "./src" } }, "autoload-dev": { "files": [ "tests/AppKernel.php" ] } } composer.json
128. { "name": "acme/billing-bridge", "description": "Handles the infrastructure for the billing package", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3", "ext-PDO": "*", "ext-json": "*", "acme/billing-package": "*@dev", "symfony/config": ">=2.8,<3.5", "symfony/http-kernel": ">=2.8,<3.5", "symfony/dependency-injection": "<3.5" }, "require-dev": { "phpunit/phpunit": "^8" }, "autoload": { "psr-4": { "Acme\\Bridge\\Billing\\": "./src" } }, "autoload-dev": { "files": [ "tests/AppKernel.php" ] } } composer.json
129. { "name": "acme/billing-bridge", "description": "Handles the infrastructure for the billing package", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3", "ext-PDO": "*", "ext-json": "*", "acme/billing-package": "*@dev", "symfony/config": ">=2.8,<3.5", "symfony/http-kernel": ">=2.8,<3.5", "symfony/dependency-injection": "<3.5" }, "require-dev": { "phpunit/phpunit": "^8" }, "autoload": { "psr-4": { "Acme\\Bridge\\Billing\\": "./src" } }, "autoload-dev": { "files": [ "tests/AppKernel.php" ] } } composer.json
130. { "name": "acme/billing-bridge", "description": "Handles the infrastructure for the billing package", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3", "ext-PDO": "*", "ext-json": "*", "acme/billing-package": "*@dev", "symfony/config": ">=2.8,<3.5", "symfony/http-kernel": ">=2.8,<3.5", "symfony/dependency-injection": "<3.5" }, "require-dev": { "phpunit/phpunit": "^8" }, "autoload": { "psr-4": { "Acme\\Bridge\\Billing\\": "./src" } }, "autoload-dev": { "files": [ "tests/AppKernel.php" ] } } composer.json
131. { "name": "acme/billing-bridge", "description": "Handles the infrastructure for the billing package", "version": "0.0.1", "license": "proprietary", "require": { "php": ">=7.3", "ext-PDO": "*", "ext-json": "*", "acme/billing-package": "*@dev", "symfony/config": ">=2.8,<3.5", "symfony/http-kernel": ">=2.8,<3.5", "symfony/dependency-injection": "<3.5" }, "require-dev": { "phpunit/phpunit": "^8" }, "autoload": { "psr-4": { "Acme\\Bridge\\Billing\\": "./src" } }, "autoload-dev": { "files": [ "tests/AppKernel.php" ] } } composer.json
132. src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml composer.json tests AppKernel.php <?php namespace Acme\Bridge\Billing\DependencyInjection; use Symfony\Component\Config\Definition\Builder\TreeBuilder; use Symfony\Component\Config\Definition\ConfigurationInterface; class Configuration implements ConfigurationInterface { public function getConfigTreeBuilder() { $treeBuilder = new TreeBuilder(); $rootNode = $treeBuilder->root('billing_bridge'); $rootNode ->children() ->arrayNode('services') ->isRequired() ->children() ->scalarNode('pdo_connection') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->arrayNode('parameters') ->isRequired() ->children() ->scalarNode('payment_provider_key') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->end(); Configuration.php StripePaymentProcessor.php
133. src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\DependencyInjection; use Symfony\Component\Config\Definition\Builder\TreeBuilder; use Symfony\Component\Config\Definition\ConfigurationInterface; class Configuration implements ConfigurationInterface { public function getConfigTreeBuilder() { $treeBuilder = new TreeBuilder(); $rootNode = $treeBuilder->root('billing_bridge'); $rootNode ->children() ->arrayNode('services') ->isRequired() ->children() ->scalarNode('pdo_connection') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->arrayNode('parameters') ->isRequired() ->children() ->scalarNode('payment_provider_key') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->end(); StripePaymentProcessor.php
134. src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\DependencyInjection; use Symfony\Component\Config\Definition\Builder\TreeBuilder; use Symfony\Component\Config\Definition\ConfigurationInterface; class Configuration implements ConfigurationInterface { public function getConfigTreeBuilder() { $treeBuilder = new TreeBuilder(); $rootNode = $treeBuilder->root('billing_bridge'); $rootNode ->children() ->arrayNode('services') ->isRequired() ->children() ->scalarNode('pdo_connection') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->arrayNode('parameters') ->isRequired() ->children() ->scalarNode('payment_provider_key') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->end(); StripePaymentProcessor.php
135. <?php namespace Acme\Bridge\Billing\DependencyInjection; use Symfony\Component\Config\Definition\Builder\TreeBuilder; use Symfony\Component\Config\Definition\ConfigurationInterface; class Configuration implements ConfigurationInterface { public function getConfigTreeBuilder() { $treeBuilder = new TreeBuilder(); $rootNode = $treeBuilder->root('billing_bridge'); $rootNode ->children() ->arrayNode('services') ->isRequired() ->children() ->scalarNode('pdo_connection') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->arrayNode('parameters') ->isRequired() ->children() ->scalarNode('payment_provider_key') ->isRequired() ->cannotBeEmpty() ->end() ->end() ->end() ->end(); src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml composer.json tests AppKernel.php Configuration.php StripePaymentProcessor.php
136. src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\DependencyInjection; use InvalidArgumentException; use Symfony\Component\Config\FileLocator; use Symfony\Component\DependencyInjection\ContainerBuilder; use Symfony\Component\DependencyInjection\Loader; use Symfony\Component\HttpKernel\DependencyInjection\Extension; class BillingBridgeExtension extends Extension { public function load(array $configs, ContainerBuilder $container): void { $config = $this->processConfiguration(new Configuration(), $configs); $loader = new Loader\XmlFileLoader( $container, new FileLocator(__DIR__ . '/../Resources/config') ); $container->setAlias( 'billing_bridge.pdo_connection', $config['services']['pdo_connection'] ); $container->setAlias( 'billing_bridge.payment_provider_key', $config['parameters']['payment_provider_key'] ); $loader->load('services.xml'); } } StripePaymentProcessor.php
137. src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\DependencyInjection; use InvalidArgumentException; use Symfony\Component\Config\FileLocator; use Symfony\Component\DependencyInjection\ContainerBuilder; use Symfony\Component\DependencyInjection\Loader; use Symfony\Component\HttpKernel\DependencyInjection\Extension; class BillingBridgeExtension extends Extension { public function load(array $configs, ContainerBuilder $container): void { $config = $this->processConfiguration(new Configuration(), $configs); $loader = new Loader\XmlFileLoader( $container, new FileLocator(__DIR__ . '/../Resources/config') ); $container->setAlias( 'billing_bridge.pdo_connection', $config['services']['pdo_connection'] ); $container->setAlias( 'billing_bridge.payment_provider_key', $config['parameters']['payment_provider_key'] ); $loader->load('services.xml'); } } StripePaymentProcessor.php
138. src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\DependencyInjection; use InvalidArgumentException; use Symfony\Component\Config\FileLocator; use Symfony\Component\DependencyInjection\ContainerBuilder; use Symfony\Component\DependencyInjection\Loader; use Symfony\Component\HttpKernel\DependencyInjection\Extension; class BillingBridgeExtension extends Extension { public function load(array $configs, ContainerBuilder $container): void { $config = $this->processConfiguration(new Configuration(), $configs); $loader = new Loader\XmlFileLoader( $container, new FileLocator(__DIR__ . '/../Resources/config') ); $container->setAlias( 'billing_bridge.pdo_connection', $config['services']['pdo_connection'] ); $container->setAlias( 'billing_bridge.payment_provider_key', $config['parameters']['payment_provider_key'] ); $loader->load('services.xml'); } } StripePaymentProcessor.php
139. src DependencyInjection BillingBridgeExtension.php PaymentProcessor StripePaymentProcessor.php Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\Adapter; use Acme\Package\Billing\PaymentProcessor; class StripePaymentProcessor implements PaymentProcessor { private $stripeApiKey; public function __construct(string $stripeApiKey) { $this->stripeApiKey = $stripeApiKey; } public function debitAccount(Customer $customer, int $amount): void { \Stripe\Stripe::setApiKey($this->stripeApiKey); \Stripe\Charge::create([ "amount" => $amount, "currency" => "gbp", "source" => $customer->getAuthToken() ]); } public function fetchTransactions(Customer $customer): array { // ... } }
140. src DependencyInjection BillingBridgeExtension.php PaymentProcessor StripePaymentProcessor.php Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\Adapter; use Acme\Package\Billing\PaymentProcessor; class StripePaymentProcessor implements PaymentProcessor { private $stripeApiKey; public function __construct(string $stripeApiKey) { $this->stripeApiKey = $stripeApiKey; } public function debitAccount(Customer $customer, int $amount): void { \Stripe\Stripe::setApiKey($this->stripeApiKey); \Stripe\Charge::create([ "amount" => $amount, "currency" => "gbp", "source" => $customer->getAuthToken() ]); } public function fetchTransactions(Customer $customer): array { // ... } }
141. src DependencyInjection BillingBridgeExtension.php PaymentProcessor StripePaymentProcessor.php Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\Adapter; use Acme\Package\Billing\PaymentProcessor; class StripePaymentProcessor implements PaymentProcessor { private $stripeApiKey; public function __construct(string $stripeApiKey) { $this->stripeApiKey = $stripeApiKey; } public function debitAccount(Customer $customer, int $amount): void { // ... } public function fetchTransactions(Customer $customer): array { \Stripe\Stripe::setApiKey($this->stripeApiKey); $list = \Stripe\Charge::all([ "customer" => $customer->getAuthToken() ]); return array_map(function ($payment) { return new PaymentDto($payment['name'], $payment['amount']); }, $list); } }
142. src DependencyInjection BillingBridgeExtension.php PaymentProcessor StripePaymentProcessor.php Resources Config services.xml composer.json tests AppKernel.php Configuration.php <?php namespace Acme\Bridge\Billing\Adapter; use Acme\Package\Billing\PaymentProcessor; class StripePaymentProcessor implements PaymentProcessor { private $stripeApiKey; public function __construct(string $stripeApiKey) { $this->stripeApiKey = $stripeApiKey; } public function debitAccount(Customer $customer, int $amount): void { // ... } public function fetchTransactions(Customer $customer): array { \Stripe\Stripe::setApiKey($this->stripeApiKey); $list = \Stripe\Charge::all([ "customer" => $customer->getAuthToken() ]); return array_map(function ($payment) { return new PaymentDto($payment['name'], $payment['amount']); }, $list); } }
143. <?php namespace Acme\Bridge\Billing\Repository; use Acme\Package\Billing\CustomerRepository; class PdoCustomerRepository implements CustomerRepository { private $connection; public function __construct(\PDO $connection) { $this->connection = $connection; } public function find(int $customerId): Customer { $query = $this->connection ->prepare('SELECT name, token FROM customer_accounts WHERE id = :id'); $query->bindValue(':id', $customerId); $result = $query->execute(); $customer = $result->fetchAll(\PDO::FETCH_ASSOC); return new Customer($customer[0]['name'], $customer[0]['token']); } } src DependencyInjection BillingBridgeExtension.php PaymentProcessor StripePaymentProcessor.php Resources Config services.xml tests AppKernel.php Configuration.php Repository PdoCustomerRepository.php
144. <?php namespace Acme\Bridge\Billing\Repository; use Acme\Package\Billing\CustomerRepository; class PdoCustomerRepository implements CustomerRepository { private $connection; public function __construct(\PDO $connection) { $this->connection = $connection; } public function find(int $customerId): Customer { $query = $this->connection ->prepare('SELECT name, token FROM customer_accounts WHERE id = :id'); $query->bindValue(':id', $customerId); $result = $query->execute(); $customer = $result->fetchAll(\PDO::FETCH_ASSOC); return new Customer($customer[0]['name'], $customer[0]['token']); } } src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml tests AppKernel.php Configuration.php Repository PdoCustomerRepository.php StripePaymentProcessor.php
145. <?php namespace Acme\Bridge\Billing\Repository; use Acme\Package\Billing\CustomerRepository; class PdoCustomerRepository implements CustomerRepository { private $connection; public function __construct(\PDO $connection) { $this->connection = $connection; } public function find(int $customerId): Customer { $query = $this->connection ->prepare('SELECT name, token FROM customer_accounts WHERE id = :id'); $query->bindValue(':id', $customerId); $result = $query->execute(); $customer = $result->fetchAll(\PDO::FETCH_ASSOC); return new Customer($customer[0]['name'], $customer[0]['token']); } } src DependencyInjection BillingBridgeExtension.php PaymentProcessor Resources Config services.xml tests AppKernel.php Configuration.php Repository PdoCustomerRepository.php StripePaymentProcessor.php
146. <?xml version="1.0" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony services-1.0.xsd"> <services> <service id="acme.billing.card_payment" class="Acme\Package\Billing\CardPayment"> <argument type="service" id="billing_bridge.payment_provider" /> <argument type="service" id="billing_bridge.customer_repository" /> </service> <service id="billing_bridge.customer_repository" class="Acme\Bridge\Billing\Repository\PdoCustomerRepository" public="false"> <argument type="service" id="billing_bridge.pdo_connection" /> </service> <service id="billing_bridge.payment_provider" class="Acme\Bridge\Billing\PaymentProcessor\StripePaymentProcessor" public="false"> <argument>%billing_bridge.payment_provider_key%</argument> </service> </services> </container> src DependencyInjection PaymentProcessor Configuration.php BillingBridgeExtension.php Resources Config services.xml tests AppKernel.php Repository PdoCustomerRepository.php StripePaymentProcessor.php
147. <?xml version="1.0" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony services-1.0.xsd"> <services> <service id="acme.billing.card_payment" class="Acme\Package\Billing\CardPayment"> <argument type="service" id="billing_bridge.payment_provider" /> <argument type="service" id="billing_bridge.customer_repository" /> </service> <service id="billing_bridge.customer_repository" class="Acme\Bridge\Billing\Repository\PdoCustomerRepository" public="false"> <argument type="service" id="billing_bridge.pdo_connection" /> </service> <service id="billing_bridge.payment_provider" class="Acme\Bridge\Billing\PaymentProcessor\StripePaymentProcessor" public="false"> <argument>%billing_bridge.payment_provider_key%</argument> </service> </services> </container> src DependencyInjection PaymentProcessor Configuration.php BillingBridgeExtension.php Resources Config services.xml tests AppKernel.php Repository PdoCustomerRepository.php StripePaymentProcessor.php
148. <?xml version="1.0" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony services-1.0.xsd"> <services> <service id="acme.billing.card_payment" class="Acme\Package\Billing\CardPayment"> <argument type="service" id="billing_bridge.payment_provider" /> <argument type="service" id="billing_bridge.customer_repository" /> </service> <service id="billing_bridge.customer_repository" class="Acme\Bridge\Billing\Repository\PdoCustomerRepository" public="false"> <argument type="service" id="billing_bridge.pdo_connection" /> </service> <service id="billing_bridge.payment_provider" class="Acme\Bridge\Billing\PaymentProcessor\StripePaymentProcessor" public="false"> <argument>%billing_bridge.payment_provider_key%</argument> </service> </services> </container> src DependencyInjection PaymentProcessor Configuration.php BillingBridgeExtension.php Resources Config services.xml tests AppKernel.php Repository PdoCustomerRepository.php StripePaymentProcessor.php
149. src DependencyInjection PaymentProcessor Configuration.php BillingBridgeExtension.php Resources Config services.xml tests AppKernel.php Repository PdoCustomerRepository.php StripePaymentProcessor.php <?xml version="1.0" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony services-1.0.xsd"> <services> <service id="acme.billing.card_payment" class="Acme\Package\Billing\CardPayment"> <argument type="service" id="billing_bridge.payment_provider" /> <argument type="service" id="billing_bridge.customer_repository" /> </service> <service id="billing_bridge.customer_repository" class="Acme\Bridge\Billing\Repository\PdoCustomerRepository" public="false"> <argument type="service" id="billing_bridge.pdo_connection" /> </service> <service id="billing_bridge.payment_provider" class="Acme\Bridge\Billing\PaymentProcessor\StripePaymentProcessor" public="false"> <argument>%billing_bridge.payment_provider_key%</argument> </service> </services> </container>
150. src DependencyInjection PaymentProcessor Configuration.php BillingBridgeExtension.php Resources Config services.xml tests AppKernel.php Repository PdoCustomerRepository.php StripePaymentProcessor.php <?xml version="1.0" ?> <container xmlns="http://symfony.com/schema/dic/services" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony services-1.0.xsd"> <services> <service id="acme.billing.card_payment" class="Acme\Package\Billing\CardPayment"> <argument type="service" id="billing_bridge.payment_provider" /> <argument type="service" id="billing_bridge.customer_repository" /> </service> <service id="billing_bridge.customer_repository" class="Acme\Bridge\Billing\Repository\PdoCustomerRepository" public="false"> <argument type="service" id="billing_bridge.pdo_connection" /> </service> <service id="billing_bridge.payment_provider" class="Acme\Bridge\Billing\PaymentProcessor\StripePaymentProcessor" public="false"> <argument>%billing_bridge.payment_provider_key%</argument> </service> </services> </container>
152. $ composer require acme/billing-bridge
153. app config config.yml billing_bridge: services: pdo_connection: doctrine.dbal.billing_connection parameters: payment_provider_key: '%env(stripe_secret_key)%'
154. app config config.yml src Controller MarketplaceController.php <?php namespace App\Controller; use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route; use Symfony\Bundle\FrameworkBundle\Controller\Controller; use Symfony\Component\HttpFoundation\Response; class MarketplaceController extends Controller { public function chargeCardAction($customerId, $amount): Response { // ... $this->container ->get('acme.billing.card_payment') ->debitAccount($customerId, $amount); } public function listChargesAction($customerId): Response { // ... $charges = $this->container ->get('acme.billing.card_payment') ->listPayments($customerId); return new Response(\json_encode($charges)); } }
157. Domain Objects
158. Domain Objects Scalars / JSON
159. Domain Objects Scalars / JSON
160. Domain Objects Scalars / JSON
161. Domain Objects Scalars / JSON
162. Domain Objects Scalars / JSON
165. Unit tests Integration tests E2E tests
174. Search / buy music Upload songs Billing Profile
175. Search / buy music Upload songs Billing Profile
176. Search / buy music Upload songs Billing Profile
177. Search / buy music Upload songs Billing Profile
178. Layer Role Has domain knowledge? Services Dependencies Testing level Package Business logic Yes Provides services to bridge None / Language level Unit Bridge Wiring & Concretions Minimal Provides / forwards services to application layer Package / Symfony DI Integration Application / FW Talks to the outside world No Uses services provided by bridge layer Bridge End-to-end
179. Pros Cons Less boilerplate for creating separate services More boilerplate for integrating domain code Layers kept isolated & easily testable Scaling not 100% microservice-esque Clear separation of concerns Requires effort in understanding Easily port domain code into applications Not 100% separately deployable Easily switch between monolith or microservice Not truly asynchronous Communication via JSON between services Breaking one thing breaks all things Full log trace from request to response Low latency (method calls vs network calls)
182. WE ARE HIRING!