As developers, we know that testing is a crucial part of any development process. However, writing tests can be time-consuming, accounting for 20-30% of a developer's time. Pythagora, an open-source NPM package, changes the game by automating tests through server activity analysis. In this blog post, we'll dive into how Pythagora can help you reduce debugging time, make your development process more efficient, and create more reliable applications.

What is Pythagora?

Pythagora is an NPM package designed to create automated tests for your Node.js applications by analyzing server activity. It records all requests to your app's endpoints, along with responses and server actions, such as Mongo and Redis queries. Pythagora during testing simulates the server conditions from the time when the request was captured, allowing for consistent and accurate testing across different environments.

Setting Up Pythagora

Integrating Pythagora into your Node.js app is as simple as installing the package:

npm install pythagora

Once installed, you’re ready to start recording your integration tests with no additional setup or configuration.

To capture test data, run Pythagora in capture mode:

npx pythagora --init-command "my start command" --mode capture

After capturing your desired requests, simply stop your server and tests should be ready to go. Change the mode parameter to –mode test to run the tests:

npx pythagora --init-command "my start command" --mode test

When running tests, Pythagora creates an ephemeral database to restore data before each test execution. This ensures that tests can be run on any machine or environment without affecting the original database.

Reducing Debugging Time

With Pythagora, you no longer need to spend countless hours writing tests, as the package automatically captures and creates tests for you. This not only saves time but also ensures that your tests are consistent.

Pythagora intelligently monitors your application and generates test cases based on its observations. This eliminates the need for manual test creation and ensures that your tests are comprehensive and up-to-date with your codebase. By automating this process, developers can focus on writing high-quality code rather than worrying about creating and maintaining tests.

Example of data that Pythagora captures for each API request
Reviewing Failed Tests with the --review Flag

The --review flag in Pythagora is a convenient feature designed to make reviewing and maintaining tests more efficient and straightforward. By running the

npx pythagora --review

command, developers can easily review failed tests from the previous run, one at a time. This feature provides an interactive way to analyze test failures and make informed decisions about how to handle the discrepancies.

Interactive Test Review

When the --review command is executed, Pythagora presents each failed test individually, highlighting the differences between the test result and the captured test data. This clear visualization of discrepancies enables developers to easily identify the cause of the failure and decide on the most appropriate course of action.

The --review feature offers developers several options for handling test discrepancies. They can:

1. Accept new changes as the “new valid test”: If the changes are determined to be correct and the test should be updated accordingly, developers can accept the new changes as the new baseline for the test.
2. Delete the test due to changed functionality: If the application’s functionality has changed and the test is no longer relevant, developers can choose to delete the test altogether.
3. Skip checking the test and move to the next one: If developers want to postpone addressing the failed test and continue reviewing other tests, they can choose to skip the current test and move on to the next one.
4. Get that test run command: If developer wants to rerun only that test for debugging purpose this option will print out Pythagora command to run that specific test.
5. Quit: If developer wants to stop review process he can simply press “q”.

Efficient Test Maintenance

The --review flag in Pythagora significantly improves the efficiency of test maintenance compared to other tools. By providing a clear and interactive way to review test failures and offering flexible options for handling discrepancies, developers can quickly and easily maintain and update their tests, ensuring their application remains robust and reliable.

Debugging specific test

When a test fails, you can rerun the specific test by adding the --test-id <TEST_ID> parameter to the command. This allows you to easily debug the test with all the data it uses, making it simple to identify and fix any issues.

npx pythagora --init-command "node backend/server.js" --mode test --test-id 1fa3171b-42d4-485e-8403-4620c0d2145c

Pythagora also generates detailed code coverage reports, giving you valuable insights into which portions of your code are tested and which are not. These reports help you identify areas where your test coverage may be lacking, allowing you to concentrate your efforts on improving those sections. By being aware of any gaps in test coverage, you can ensure a more robust and reliable application.

Conclusion

Pythagora is a very promising NPM package that automates testing and reduces debugging time for developers. By recording server activity and simulating server conditions, Pythagora enables accurate and consistent testing across different environments. With its easy installation and setup, as well as its time-saving capabilities, Pythagora might soon be a must-have tool for any Node.js developer looking to supercharge their development workflow, so keep an eye on it!

Give Pythagora a try and see how it can revolutionize your testing process. Don’t forget to star the Pythagora repo to show your support and appreciation!