How To Create Your Very First API With FastAPI In Python Tutorial 2023
TLDRThis tutorial video guides viewers on creating their first API using Python's FastAPI package, which is known for its speed and convenience. The presenter demonstrates how to install FastAPI, set up a basic API with a main endpoint that returns JSON data, and use uvicorn for automatic reloading during development. The video also covers creating additional endpoints, such as one that generates random numbers with an optional user-defined limit. The use of the 'reload' flag for live updates without rerunning the script is highlighted. Finally, the presenter mentions FastAPI's automatic API documentation generation and encourages viewers to explore further by creating more complex APIs or integrating machine learning or other API interactions.
Takeaways
- 🚀 FastAPI is a modern, fast (high-performance) web framework for building APIs in Python.
- 🛠️ To get started, install FastAPI and uvicorn using pip in your Python environment.
- 📦 Import FastAPI and other necessary modules, such as random, to generate dynamic content.
- 🎯 Create an instance of the FastAPI class to serve as the entry point for your API.
- 🥳 Define your API's endpoints using decorators like `@app.get` and make them asynchronous for better performance.
- 📈 Return JSON responses easily by returning Python dictionaries; FastAPI automatically serializes them.
- 🔄 Use uvicorn with the `reload` flag to run your API server, enabling automatic reloading on code changes.
- 🌐 Test your API endpoints using a web browser or by making HTTP requests with tools like the requests library.
- 🔢 Create endpoints that return random numbers and allow users to specify parameters, like a limit, for the range.
- 📋 FastAPI automatically generates interactive API documentation, accessible via the `/docs` endpoint.
- 💡 Explore possibilities to expand your API by integrating machine learning models or interacting with other APIs.
Q & A
What is FastAPI and why is it used?
-FastAPI is a modern, fast (high-performance), web framework for building APIs with Python 3.7+ based on standard Python type hints. It is used for its quick and convenient way to create APIs.
How do you install FastAPI in a Python project?
-To install FastAPI, you open the terminal, type 'pip install', use quotation marks around 'fastapi', and then press enter to allow the installation process to complete.
What is the first step in creating an API with FastAPI?
-The first step is to create an application instance by importing FastAPI and then instantiating it.
How do you define the main endpoint in a FastAPI application?
-You define the main endpoint by using the '@app.get("/")' decorator to create an asynchronous function named 'async def root()', which serves as the root of the application.
What does the 'reload' flag do when running a FastAPI application?
-The 'reload' flag allows the application to automatically reload upon code changes, so you don't have to manually restart the server each time you make an update.
How can you test the API locally?
-You can test the API locally by using a tool like 'uvicorn' to run the application and then making requests to the local server address in a web browser or using a module like 'requests' in a Python script.
How does FastAPI handle converting Python dictionaries to JSON format?
-FastAPI automatically takes care of converting Python dictionaries to JSON format, so the developer doesn't have to manually handle this conversion.
What is the purpose of the '/docs' endpoint in FastAPI?
-The '/docs' endpoint provides auto-generated documentation for the API, which is useful for understanding the available endpoints and how to interact with them.
How can you create an endpoint that returns a random number with a specified limit?
-You can create such an endpoint by defining a route with a path parameter for the limit, using the 'random.randint' function to generate a random number within the specified range, and then returning that number in a JSON response.
What is the significance of the order of paths with identical names in FastAPI?
-In FastAPI, if there are two paths with the same name, the first one that is found will be used. Therefore, the order in which paths are defined can affect which one is matched by incoming requests.
How can you make changes to your FastAPI application without stopping and restarting the server?
-By using the 'reload' flag when running the application with 'uvicorn', changes made to the code will automatically update the running application without needing to stop and restart the server.
What are some potential uses for a FastAPI application beyond a simple random number generator?
-FastAPI applications can be used for a wide range of purposes, including creating chatbots, performing machine learning tasks, interacting with other APIs to gather and return more complex data, and more.
Outlines
🚀 Introduction to FastAPI
The video begins with an introduction to FastAPI, a high-performance web framework for building APIs quickly and easily in Python. The presenter demonstrates how to install FastAPI using pip and import it along with the random module for generating random numbers. The first step in creating an API is to create an application instance. The main endpoint is then established using the 'app.get' decorator, which is an asynchronous function that returns JSON data when the API is accessed. The presenter also explains the convenience of using FastAPI for converting Python dictionaries to JSON format automatically.
🔄 FastAPI's Hot Reload Feature
The presenter continues by discussing the installation and setup process for uvicorn, an ASGI server for running FastAPI applications. It is used to start a local server and enables the hot reload feature, which allows the API to automatically update when changes are made to the script. This feature is particularly useful as it eliminates the need to continuously rerun the program. The video then shows how to create a new endpoint that returns a random integer within a specified range, and how to customize this range by adding a parameter to the endpoint. The presenter also touches on the importance of path uniqueness in API endpoints and the automatic generation of API documentation by FastAPI, which can be accessed via the '/docs' endpoint.
📚 Conclusion and Future Directions
The video concludes with a summary of the steps taken to create a basic FastAPI application that serves as a random number generator with customizable limits. The presenter encourages viewers to experiment with the API, explore further functionalities like creating chatbots or integrating machine learning models, and interact with other APIs. The presenter also mentions the possibility of a follow-up video on creating more advanced projects or documentation. The video ends with a thank you note to the viewers and an invitation to share their thoughts on FastAPI and the content covered.
Mindmap
Keywords
💡API
💡FastAPI
💡PIP install
💡Asynchronous function
💡JSON
💡uvicon
💡Local server
💡Requests module
💡Random number generation
💡Documentation
💡Reload flag
Highlights
Introduction to creating an API with FastAPI in Python
Installation of FastAPI using pip in the terminal
Importing FastAPI and random modules for the project
Creating the app instance as the entry point to the API
Defining the main endpoint with an asynchronous function
Returning JSON response with example data
Using uvicon for automatic reloading of the app
Testing the API in a local server environment
Demonstration of the API's live functionality and response
Using the reload flag for automatic updates without rerunning the script
Creating a new endpoint to return a random number
Implementing user-defined limit for the random number generation
Explanation of path prioritization in API routing
Automatic generation of API documentation with FastAPI
Customizing the API response with additional data
Using the requests module for API interaction in other projects
Playing around with the API in the browser for testing
Stopping the server using control plus C for non-live editing
Encouragement to explore further and create more advanced projects with FastAPI