Contract vs. Approval Testing: Identifying Bugs in RESTfulBooker’s API with Specmatic and TextTest

The BEST way to find BUGS in an API | Contract vs Approval Testing – Emily Bache

Testing APIs: Specmatic vs TextTest

Emily Bache wanted to compare TextTest with Specmatic and has published a video about her experience: The BEST way to find BUGS in an API | Contract vs Approval Testing

She observes, “Specmatic works best when the spec is defined independently in an ongoing discussion about expectations between the service developers and the service consumers. Specmatic is not so much about finding bugs as agreeing expectations about an API.”

  • Emily looks into the best ways to find bugs in an API by exploring the use of Contract vs Approval Testing.
  • She takes us through an in-depth comparison of using TextTest and Specmatic to test and expose bugs in the RESTfulBooker API.
  • She explores the concept of contract testing as a means to ensure seamless communication between different teams working on services that communicate via APIs.
  • Observe the power of leveraging API specifications as executable contracts and maintaining them in a central Git repository to ensure that both providers and consumers are working with the correct version of the specification.
  • Check out her video to get a detailed breakdown of the benefits and functionalities of both TextTest and Specmatic in identifying, documenting, and preventing bugs in API development.

Key Takeaways from the video

1. Exploring API Bugs: Emily demonstrates how RESTfulBooker, intentionally filled with bugs, provides a playground for discovering issues through manual testing and automated tools like Specmatic and Text Test.

2. Contract Testing with Specmatic: Emily reveals how Specmatic facilitates contract testing by creating and running tests based on API specifications, ensuring alignment with the expected behaviors. She goes on to explain how this enables teams working on different services to independently verify if their respective services / components comply with the agreed API contract. Emily also discusses how Specmatic is able to use the examples in the OpenAPI specification for generating tests.

3. Approval Testing with Text Test: Emily discusses the features and benefits of Text Test, emphasizing its capacity for approval testing by comparing the actual API responses with previously approved outputs. This tool aids in exposing bugs and ensuring proper functionality through meticulous testing and validation.

4. Effective Bug Identification: The video sheds light on the significance of thorough bug identification through a combination of manual exploratory testing and automated testing tools, showcasing how both approaches contribute to comprehensive bug detection.

Elevating API Testing with Contract Driven Development

In the evolving landscape of microservices and API-driven architectures, Contract Driven Development (CDD) emerges as a game-changer. By leveraging API specifications as executable contracts, CDD enables seamless collaboration between service providers and consumers, fostering a robust and reliable API ecosystem.

Explore the power of Contract Driven Development in API testing by embracing Specmatic and TextTest. These tools provide indispensable support for developers and testers, ensuring the robustness and reliability of your API infrastructure.

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