Debugging FastAPI Applications
Master debugging techniques for FastAPI, including using IDE debuggers and logging.
What is Debugging?
Welcome to debugging! As developers, we don't just write code; we also fix it. Debugging is the process of finding and resolving errors or 'bugs' in your software.
It's an essential skill that helps you understand how your code truly behaves, not just how you think it should.
- Find Errors: Pinpoint exactly where issues occur.
- Understand Flow: Trace execution path.
- Inspect State: See variable values at any point.
The Simple `print()` Debug
The most basic form of debugging is using print() statements. You can sprinkle them throughout your code to see values of variables or confirm if a certain part of your code is being executed.
While quick, print() statements can clutter your output and need to be manually removed later.
Try running this simple example:
def calculate_sum(a, b):
print(f"DEBUG: Input: a={a}, b={b}")
result = a + b
print(f"DEBUG: Output: result={result}")
return result
if __name__ == "__main__":
print("Starting calculation...")
total = calculate_sum(5, 3)
print(f"Final total: {total}")All lessons in this course
- Unit Testing with Pytest
- Integration Testing FastAPI Endpoints
- Debugging FastAPI Applications
- Mocking Dependencies in FastAPI Tests