Let's take care of our micro-services

Samuel RozeInviqa

twitter.com/samuelrozegithub.com/sroze

(micro)services

Monolith costs a lot...(only) on the long run !

Microservices are flexible

but introduces complexity!

Key points» Organisation

» Deployment pipeline

» Monitoring & debugging

» Fault tolerance

Key pointsOrganisation

» In the teamsSpotify's squads: the team knows about their services

» Between the teamsResponsibility boundaries, communication, shared goals

Key pointsDeployment pipeline

» New servicesCreate new services within hours

» Continuous DeliverySmall and fast deployments

» Delivery as a ServiceThe teams can change the technology stack themselves

Key pointsMonitoring and debugging

» Pro-active monitoringhealth-checks

» Active error logging and altertingknow what is going on

» Debugging after incidenttracing between services

Key pointsFault tolerance

» Perfection, hopes or embracing faultsBecause that will happen

» ArchitectureA server dies

» ApplicationA service is down or throwing exceptions

Key points, again» Organisation

» Deployment pipeline

» Monitoring & debugging

» Fault tolerance

Environments

Fault tolerance

Tolerance github.com/Tolerance/Tolerance

tolerance.io

ToleranceOperations

Take something that can fail...$comments = $client->getLastComments();

Wrap into an Operationuse Tolerance\Operation\Callback;

$operation = new Callback(function() use ($client) { return $client->getLastComments();});

Run the operation$comments = $runner->run($operation);

 Be fault tolerantby decorating the operation

runners

Retry

$waitStrategy = new CountLimited( new ExponentialBackOff( new SleepWaiter(), 1 ), 10);

$runner = new RetryOperationRunner( $decoratedRunner, $waitStrategy);

Fallback

$staticResultFactory = new StaticResultFactory([]);

$runner = new FallbackOperationRunner( $decoratedRunner, $staticResultFactory);

// ...$messages = $runner->run($operation);

Other operation runners...

Rate limiting

$rateLimit = new LeakyBucket( new InMemoryStorage(), new TimeRate(10, TimeRate::PER_SECOND));

$runner = new RateLimitedOperationRunner( $decoratedRunner, $rateLimit, new SleepWaiter());

Buffered (ie postponed runs)

$buffer = new InMemoryOperationBuffer();$bufferedRunner = new BufferedOperationRunner($runner, $buffer);

// Run operations$bufferedRunner->run($firstOperation);$bufferedRunner->run($secondOperation);

// ...// ...

$results = $bufferedRunner->runBufferedOperations();

AppKernel.phpnew Tolerance\Bridge\Symfony\Bundle

\ToleranceBundle();

Get runners from YAML

tolerance: operation_runners: default: retry: # ... callback: # ... buffered: # ... fallback: # ...

 Buffered runner

A lot of operations don't have to be executed just now.

$runner->run(new Callback(function() { $this->pushMyBusinessMetricToElasticSearch();}));

» Run operations on kernel.terminate event

 AOPAspect Oriented Programming

 AOP

tolerance: aop: ~

Wrap your services into operationsjust by using a tolerance.operation_wrapper tag

<services> <service id="app.comments_client" class="App\Comments\HttpClient">

<tag name="tolerance.operation_wrapper" methods="getLastComments" runner="tolerance.operation_runner.default" />

</service></services>

Use your service as usual

$comments = $this->client->getLastComments();

Tolerance MessageProfile

MessageProfile

tolerance: message_profile: enabled: true storage: neo4j: neo4j_client_service_id

current_peer: service: "My service" environment: %kernel.environment% version: 12345

MessageProfileIntegrations

» Guzzle

» Monolog

» RabbitMqBundle

» HttpFoundation

» PSR-7

Thank you!@samuelroze

https://github.com/Tolerance/Tolerance

https://joind.in/talk/2f75b