How do you write test cases for API testing using Karate?

1 Install and configure Karate

The first step is to install and configure Karate on your machine. You can use Karate as a standalone tool or as a dependency in your Maven or Gradle project. You will also need Java 8 or higher and an IDE of your choice. To verify that Karate is working, you can run a sample test from the command line or the IDE.

2 Create a feature file

The next step is to create a feature file that contains your test scenarios. A feature file is a plain text file with a .feature extension that follows the Gherkin syntax. Gherkin is a language that describes the behavior of your API in a human-readable and structured way. A feature file consists of a feature name, an optional description, and one or more scenarios. Each scenario has a name, an optional background, and a sequence of steps.

3 Write test steps

The third step is to write test steps for each scenario. A test step is a line that starts with a keyword, such as Given, When, Then, And, or But, followed by a statement that defines an action or an assertion. Karate provides a rich set of built-in keywords and expressions that allow you to perform various operations on your API, such as sending requests, receiving responses, parsing data, validating results, and handling errors. You can also use variables, parameters, and data tables to make your test steps more dynamic and reusable.

5 Run and report tests

The fifth step is to run and report your tests. You can run your tests from the command line or the IDE using the Karate runner or the JUnit runner. You can also integrate your tests with other tools and frameworks, such as Cucumber, TestNG, Selenium, or Jenkins. Karate generates HTML and JSON reports that show the details and status of your tests, such as the feature name, scenario name, test steps, request and response data, and error messages. You can also customize and extend your reports using plugins or third-party libraries.

6 Debug and refactor tests

The final step is to debug and refactor your tests. You can debug your tests using the Karate IDE or the Karate logger. The Karate IDE is a graphical user interface that allows you to edit, run, and debug your feature files in a browser. The Karate logger is a console output that shows the execution and evaluation of your test steps, variables, and expressions. You can also use breakpoints, log statements, and print statements to inspect and troubleshoot your tests. To refactor your tests, you can use the Karate DSL features and best practices to make your tests more readable, maintainable, and modular.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?