fastapi有查询约束异常吗?

Is there any Query constraint exception on fastapi?

我使用的是 fastapi 0.70.0,python 3.8.10。

我期待查询在查询时引发 RequestValidationError(或其他)/items/0(因为 0 不是 gte=1)

我拿了fastapi示例代码,添加了Query参数约束(item 0是不允许的):

from fastapi import FastAPI, HTTPException, Query
from fastapi.exceptions import RequestValidationError
from fastapi.responses import PlainTextResponse

app = FastAPI()

@app.exception_handler(RequestValidationError)
async def validation_exception_handler(request, exc):
    return PlainTextResponse(str(exc), status_code=400)

@app.get("/items/{item_id}")
async def read_item(item_id: int = Query(default=1, gte=1)):             # /!\ Important line.
    if item_id == 3:
        raise HTTPException(status_code=418, detail="Nope! I don't like 3.")
    return {"item_id": item_id}

很少查询:

项目 1:有效查询:

curl http://127.0.0.1:8000/items/1             # Return item_id as expected.
{"item_id": 1}

a项:异常,“a”不是整数:

curl http://127.0.0.1:8000/items/a             # RequestValidationError as expected

项目 0:未引发异常,0 不允许。

curl http://127.0.0.1:8000/items/0             # ô_O, no exception, 0 is not gte=1 
{"item_id": 0}

那么,如果没有引发异常,查询约束还不可用吗?

没有gte这样的键。您需要使用:

  • gt - 大于,或
  • ge - 大于等于

Number validations

@app.get("/items/{item_id}")
async def read_item(item_id: int = Query(default=1, ge=1)):             # /!\ Important line.
    if item_id == 3:
        raise HTTPException(status_code=418, detail="Nope! I don't like 3.")
    return {"item_id": item_id}

参数定义为ge: Optional[float] = None,,不是gte:

from fastapi import FastAPI, Query

app = FastAPI()

@app.get('/')
async def get_magic(a: int = Query(default=1, ge=1)):
    return {'foo': a}
    

if __name__ == '__main__':
    import uvicorn

    uvicorn.run('foo:app', port=4008, reload=True)

?a=0 调用它给出了预期的错误:

{"detail":[{"loc":["query","a"],"msg":"ensure this value is greater than or equal to 1","type":"value_error.number.not_ge","ctx":{"limit_value":1}}]}