IT talk & Lublin Java User Group

Bootiful Testing with Spring Boot! (EN), Mario Gray (Pivotal)

The Following Bob Martin's 3 laws of TDD apply to this talk:

You are not allowed to write any production code unless it is to make a failing unit test pass.

You are not allowed to write any more of a unit test than is sufficient to fail; and compilation failures are failures.

You are not allowed to write any more production code than is sufficient to pass the one failing unit test.

Developing and deploying with low defect rates is a guessing game without proper testing.

Code written to be tested is decoupled, has better SOLID principle adherence, thus leading to better architecture. Testing helps us build confidence and good judgement into our code. You will gain insight on how to solve the hard parts (consumer/producer) of distributed computing unit tests with the best of breed Spring Boot test tools.

In this hands-on live-coding presentation, Mario will guide you through identifying testing details using Spring-Boot and it's comprehensive unit-test support. We review methods for asserting test expectations and we explore Spring Test Slices to expose an isolated test harnesses for verifying web, and persistence components.. We will discover how tests become brittle over time, and how we can fight that by identifying common producer and consumer requirements mismatches. We finally demonstrate the powerful Spring-Cloud-Contract component to solve this mismatch by allowing consumer tests to directly correlate with the producer's expectations.

Larger and thus sensitive application deployments can take hours, or days in order to gain trust in the new code. Would you like to strengthen that confidence to keep your applications running smooth and deploying often? Test Driven Development instruments this aspiration, enables enhanced SOLID principle adherence and gives a clear path to CD/CI. Add confidence, good judgement, and increase code value with best of breed testing tools and Spring Boot.

Hystrix - kiedy niepowodzenie jest nieuniknione (PL), Grzegorz Szymański (DataArt)

To prezentacja o problemach, które mogą wystąpić kiedy w swojej aplikacji korzystamy z zewnętrznych systemów. Pokazuje, w jaki sposób możemy radzić sobie z takimi problemami, i jak Hystrix (w niektórych przypadkach) może nam w tym pomóc. Prezentacja obejmuje krótkie wprowadzenie do problemów w systemach rozproszonych, przegląd dostępnych metod radzenia sobie z nimi, przykłady użycia biblioteki Hystrix oraz demo i szczegóły dotyczące konfiguracji.

Why Contract Tests Matter? (EN), Marcin Grzejszczak (Pivotal), live coding

You are writing integration tests, aren't you? Have you ever needed to stub the HTTP or a messaging call? Have your tests passed? That's awesome, but it doesn't mean that your application is working fine or that your system will not break on end to end tests.

In this presentation, you'll see a system composing of two apps written from scratch. We'll present the most frequent mistakes that take place during writing integration tests and we'll show how you can use contract testing to fix those problems.