Writing contract tests for a synchronous API

Contract testing and integration testing are two sides of the same coin. Integration tests ensure that a consumer is calling a provider service correctly, whereas contract tests ensure that the provider service continues to meet its obligations to its consumers and that any changes are backward-compatible. These tests are also consumer driven. This means that the consumer submits a pull request to the provider's project to add these additional tests. The provider is not supposed to change these tests. If a contract test breaks, it implies that a backwards-incompatible change has been made. The provider has to make the change compatible and then work with the consumer team to create an upgrade roadmap.

How to do it...

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