main-tutorial-session-1-6.py

from enum import Enum
from fastapi import FastAPI, Response, Query, Path
from pydantic import BaseModel

app = FastAPI()

@app.get("/")
async def root():
    return{"Hello World"}

@app.post("/")
async def post():
    return{"message": "hello from the post message"}

@app.put("/")
async def put():
    return{"message": "hello from the put route"}

#it is important to note that it must use static route before the dynamic route
@app.get("/users/me")
async def get_current_user():
    return {"message": "this is the current user"}

@app.get("/users/{user_id}")
async def get_user(user_id: str):
    return {"user_id": user_id}

class FoodEnum(str, Enum):
    fruits = "fruits"
    vegatables = "vegatables"
    diary = "diary"

@app.get("/foods/{food_name}")
async def get_food(food_name: FoodEnum):
    if food_name == FoodEnum.vegatables:
        return {"food_name": food_name, "message": "you are very healthy"}
    
    if food_name == FoodEnum.fruits:
        return {"food_name": food_name, "message": "you are still healthy but like sweet"}
    else:
        return {"food_name": food_name, "message": "I like milk"}


# fake_items_db = [{"item_name": "Foo"}, {"item_name": "Bar"}, {"item_name": "Baz"}]
# @app.get("/items")
# async def list_items(skip: int = 0, limit: int = 10):
#     return fake_items_db[skip : skip + limit]

@app.get("/items/{item_id}")
async def get_item(item_id: str, sample_query_param: str, q: str | None = None, short: bool = False):
    item = {"item_id": item_id, "sample_query_param": sample_query_param}
    if q:
        item.update({"q": q})
    if not short:
        item.update({"description": "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas pharetra."})
    return item

@app.get("/users/{user_id}/items/{item_id}")
async def get_user_item(user_id: int, item_id: str, q: str | None = None, short: bool = False):
    item = {"item_id": item_id, "owner_id": user_id}
    if q:
        item.update({"q": q})
    if not short:
        item.update({"description": "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas pharetra."})
    return item
    
class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None

@app.post("/items")
async def create_item(item: Item):
    item_dict = item.dict()
    if item.tax:
        price_with_tax = item.price + item.tax
        item_dict.update({"Price_with_tax": price_with_tax})
    return item_dict

@app.put("/items/{item.id}")
async def create_item_with_put(item_id: int, item: Item, q: str | None = None):
    result = {"item_id": item_id, **item.dict()}
    if q:
        result.update({"q": q})
    return result

@app.get("/items")
## the following is set the "q" become options - only valid for python 3.10 or later
# async def read_items(q: str | None = None):

## the following is set the query has default value, min and max lenght
# async def read_items(q: str = Query("fixedquery", min_length=3, max_length=10)):

## the following "..." can set as NO default value but the field is mandatory
# async def read_items(q: str = Query(..., min_length=3, max_length=10)):

## the following allows input multiple possible values. If require default vales, change the Query["Foo", "Bar"]
# async def read_items(q: list[str] | None = Query(["Foo", "Bar"])):

## the following shows multiple default fields can add to this function. One specific value call "alias", as defult the 
## python not take "-" (hype) as the URL, however if use "alias", it will replace "q" to the name of "alias" in the URL
async def read_items(q: str | None = Query(
    None, 
    min_length=3, 
    max_length=10, 
    title="Sample query string", 
    description="this is a sample query string", 
    deprecated=True,
    alias="item-query"
    )):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})
    return results

## The following example show how to hidden the query in the API.
@app.get("/items_hidden")
async def hidden_query_route(hidden_query: str | None = Query(None, include_in_schema=False)):
    if hidden_query:
        return {"hidden_query": hidden_query}
    return {"hidden_query": "Not Found"}

## The following example show how to validate the input information.
@app.get("/items_validation/{item_id}")
## Use "(...)" it can set no default but input is mandatory.
# async def read_items_validation(
#     item_id: int = Path(..., title= "The ID of items to get"), 
#     q: str | None = Query(None, alias="item-query")
#     ):

## If put q:str after the item_id, Python will consider it is part of default value, so it makes "q: str" doesn't work.
## However, if add "*," above the items ID, it will tell Python that after "*,", all other parameter consider as query. 
async def read_items_validation(
    *, 
    item_id: int = Path(..., title= "The ID of items to get", gt=10, lt=100), 
    q: str,
    size: float = Query(..., gt=0, lt=7.75)
    ):
    results = {"item_id": item_id, "size": size}
    if q:
        results.update({"q": q})
    return results