Building APIs with FastAPI · 12-day planAll days
Day 2 of 12 25 minPathQueryValidation
Read values from the URL. Capture parts of the path, add optional query parameters with defaults, let type hints convert and validate everything for you, restrict choices with enums, and add limits with Path and Query.
By the end of today you can
- Capture path parameters like /books/{book_id}
- Add query parameters with defaults and optional values
- Use type hints so FastAPI converts and validates input
- Limit choices with Enum and ranges with Path and Query
- Read the 422 error FastAPI returns for invalid input
What's inside
- 5 sections
- 3 diagrams and mind maps
- 4 code examples you can run
- 5-question quiz
- 1Path parameters
- 2Query parameters
- 3Order matters
- 4Fixed choices and limits
- 5Reading a 422
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