2023-04-17 –, Kuppelsaal
In this talk, we will explore how to use the FastAPI web framework and Celery task queue to build reliable and scalable web applications in a test-driven manner. We will start by setting up a testing environment and writing unit tests for the core functionality of our application. Next, we will use FastAPI to create an api to perform some long-running task. Finally, we will then see how Celery can help us offload long-running tasks and improve the performance of our application.
By the end of this talk, attendees will have a strong understanding of TDD and how to apply it to your FastAPI and Celery projects, and you will be able to write tests that ensure the reliability and maintainability of your code.
- Introduction (1 min)
- Title of the talk and speaker's name: This section introduces the title of the talk and the speaker's name, and current role of the speaker.
- Overview of the topics covered in the talk: This section introduces the main themes and goals of the talk, and gives the audience a sense of what they can expect to learn. - What is Test-Driven Development (TDD)? (2 min)
- Definition of TDD and how it fits into the software development process: This section defines TDD and explains how it fits into the software development process. It will highlight the benefits of TDD such as improved quality, reduced debugging time, and faster development. - Setting up a dockerized Development Environment for a Math API (5 min)
- Installing the necessary tools and libraries with Docker: This section covers the steps to install the necessary tools and libraries for testing, such as FastAPI, Celery, and a testing framework.
- Setting up a testing database with Docker: This subsection explains how to set up a testing database (PostgreSQL) using Docker. It can include instructions for pulling the Docker image, running the container, and configuring the connection.
- Configuring the application to use the testing database: This sub-section covers the steps to configure the application to use the testing database during testing. It can include instructions for setting up environment variables or config files to switch between different databases.
- Writing a basic test case: This subsection provides an example of a basic test case that verifies the setup of the testing environment. It will include a demonstration for running the test and checking the results. - Writing Unit Tests (7 min)
- Identifying the core functionality and behavior of the application: This section discusses how to identify the core functionality and behavior of the application, and how to break it down into smaller pieces that can be tested separately. It can include tips on how to prioritize the tests and focus on the most important or risky areas of the code.
- Writing test cases to cover the different scenarios and edge cases: This sub-section covers the steps to write test cases that cover the different scenarios and edge cases for the core functionality of the application. It can include examples of different types of tests, such as positive, negative, and boundary tests.
- Using mocks and fixtures to isolate the tests: This subsection explains how to use mocks and fixtures to isolate the tests from external dependencies and control the input and output. It can include examples of how to use these techniques to test different parts of the application in isolation. - Building the API with FastAPI and Celery (8 min)
- Setting up a FastAPI application: This section introduces FastAPI, and explains its key features and benefits. It will include a demonstration of how to use FastAPI to build a simple API using TDD.
- Setting up a Celery worker and task queue: This subsection explains how to set up a Celery worker and task queue, and how to configure the application to use them. It can include instructions on how to install Celery, create a Celery instance, and define the queue and backend.
- Defining tasks as functions and decorating them with Celery's @task decorator: This sub-section covers the steps to define tasks as functions and decorate them with Celery's @task decorator. It can include examples of how to define tasks and pass arguments and options to them.
- Using the Celery client to trigger tasks and receive the results: This subsection explains how to use the Celery client to trigger tasks and receive the results. It can include instructions on how to send tasks and wait for the results, and how to handle errors and exceptions. - Conclusion and Next Steps (2 min)
- Recap of the main points and takeaways from the talk: This section provides a brief summary of the main points and takeaways from the talk, and highlights the key skills and knowledge that the attendees have learned.
- Suggestions for further learning and resources: This subsection provides suggestions for further learning and resources for the attendees to dive deeper into TDD and FastAPI/Celery development. It can include links to tutorials, documentation, and other resources that can help the attendees continue learning and practicing what they have learned in the talk.
- Encouragement for attendees to apply these techniques to their own projects: This subsection encourages the attendees to apply the techniques and skills they have learned in the talk to their own projects, and to share their experiences and feedback with the community. - Question/Answer (5 min)
Intermediate
Expected audience expertise: Python –Intermediate
Abstract as a tweet –Build reliable and maintainable APIs with FastAPI and Celery using test-driven development (TDD)! Learn how to set up a testing environment, write unit and integration tests, and use mocks and fixtures to isolate and control the tests.
