Speakers: Nithya & Stephan Genre & level: Backend, Way of working, Medior Are you running into interface problems in our increasingly microservices based landscape? Is updating your APIs a hassle? Are your consumers breaking because of your API changes? Let me introduce contract testing as a part of the solution for these problems. Contract testing is a relatively new kid on the testing block. In which we let consumers define contracts for our services so that we can confidently change our APIS when we want to, and if we introduce a breaking change we will know who is affected. This talk will focus on the practical implementation of contract testing. We will write some code examples in both Pact and Spring Cloud Contract so you can make an informed choice about which framework you want to use if you decide to implement contract testing.

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Checkout Service - Consumer Order Candidate Service - Provider

5. We know the individual modules work
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6. All the modules in the system work together
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7. Check the integration with an mock of the external dependency
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8. • Mock is a method/object that simulates the behavior of a real method/object in controlled ways.
• Stubs are programs that simulate the behaviors of software components (or modules) that a
module undergoing tests depends on.
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14. Test the service in the real integrated environment
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Checkout Service - Consumer Order Candidate Service - Provider

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30. Developing Contracts with Spring Cloud Contract
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31. • Replacing the existing WSP Checkout
• Starting with multiple teams
• Front-end team (WSP Checkout)
• API team (Checkout API)
• Needed
• Some way to define API behaviour without API being available (Mocks)
• Being able to work independently without getting ‘out-of-sync’
• Solution
• Formalize using Contract defintions and automate verification
Webshop Checkout Project
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visualisation of the contracts
dependencies between all known
consumers and producers

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39. till next bol.com
Stephan Oudmaijer