Bayan binciken nau'i, FastAPI yana ba ka damar saka ƙuntatawa ga shafukan/ƙuntatawa sibobbinsa da filayen kididdigewa ta amfani da Query, Path, da Field — tilasta doka kamar tsawon, jeri da alamu, tare da kurakuran 422 da ba a ɗora ba ta atomatik da takaitawa idan suka rabu.
from fastapi import Query, Path
@app.get("/items")
def search(
q: str = Query(min_length=3, max_length=50), # string length bounds
page: int = Query(default=1, ge=1), # >= 1
limit: int = Query(default=10, ge=1, le=100), # 1 <= limit <= 100
code: str = Query(pattern=r"^[A-Z]{3}$"), # regex pattern
):
...
@app.get("/items/{item_id}")
def get(item_id: int = Path(ge=1)): # path param must be >= 1
...
Query() da Path() suka saka ƙuntatawa ga sibobbinsa ƙuntatawa da shafukan. Gaske gida: min_length/max_length (jimloli), ge/gt/le/lt (lambobi), pattern (regex). Raguwar suka samar da kyakkyawan kurakuran 422 ta atomatik.
from pydantic import BaseModel, Field, EmailStr
class User(BaseModel):
name: str = Field(min_length=1, max_length=100)
age: int = Field(ge=0, le=120)
email: EmailStr # format validation via a type
bio: str = Field(default="", max_length=500, description="User bio")
Sabuwar daya ƙuntatawa ta amfani da jikin tambayoyin haɗi ta Field(), tabbatarwa jikin buƙatu. Nau'ikan musamman (EmailStr, HttpUrl, UUID) tabbatarwa sifofin.
q: str = Query(min_length=3, description="Search query", example="phone")
# the constraints + description + example appear in the auto-generated API docs
Kowane ƙuntatawa da ka bayyana kuma yana jikowa a takaitawar OpenAPI, don kaɗai masu amfani suna ganin doka.
Saka ƙuntatawa tabbatarwa yana mahimmanci don tsaro/ƙarfi da kyakkyawan tsarin API — bayyana doka (dasussan tsawon, jeri na lambobi, alamu na regex, nau'in siffa) suna tiyata cewa ba ta sadaukarwa ba ko na ci gaba input an yi wa radda tare da kyakkyawan kurakuran kafin ya ɗauka ga ilimin ka, wanda ya zama mahimmanci saboda ka aikatau yadda ba ka ammaci jasadin saita ba.
FastAPI ya sanya haka bayyananniya da sauƙi: ƙuntatawa Query/Path/Field za a tabbata ta atomatik (samar da kurakuran 422 da aka tsara) kuma a lokaci gida takaitawa a takaitawar API, don doka a tilasta kuma aka sanar daga bayyana jiya.
Sanin gaske ƙuntatawa da nau'ikan tabbatarwa da aka keɓe ƙarfi ne na yau da kullun don gina muki mai tsaro, mai daruruwa — haka ne ka wuce binciken nau'i na asali don tilasta doka na aiki na gaske cewa bayyananniya ka dole ya gamsuwa.