Class Resource

Source module: fastapi_utils.cbv_base

---

If you familiar with Flask-RESTful and you want to quickly create CRUD application, full of features and resources, and you also support OOP you might want to use this Resource based class

---

Similar to Flask-RESTful all we have to do is create a class at inherit from Resource

from fastapi_utils import Resource


class MyApi(Resource):
    def get(self):
        return "done"

And then in app.py

from fastapi import FastAPI

from docs.src.class_resource_view1 import MyApi
from fastapi_utils import Api


def create_app():
    app = FastAPI()
    api = Api(app)

    myapi = MyApi()
    api.add_resource(myapi, "/uri")

    return app


main = create_app()

And that’s it, You now got an app.

---

Now how to handle things when it starting to get complicated:

Resource with dependencies

Since initialization is taking place before adding the resource to the api, we can just insert our dependencies in the instance init: (app.py)

from fastapi import FastAPI
from pymongo import MongoClient

from docs.src.class_resource_view1 import MyApi
from fastapi_utils import Api


def create_app():
    app = FastAPI()
    api = Api(app)

    mongo_client = MongoClient("mongodb://localhost:27017")
    myapi = MyApi(mongo_client)
    api.add_resource(myapi, "/uri")

    return app


main = create_app()

Responses

FastApi swagger is all beautiful with the responses and fit status codes, it is no sweat to declare those.

Inside the resource class have @set_responses before the function

from pydantic import BaseModel

from fastapi_utils import Resource, set_responses


# Setup
class ResponseModel(BaseModel):
    answer: str


class ResourceAlreadyExistsModel(BaseModel):
    is_found: bool


class ResourceModel(BaseModel):
    ID: str
    name: str


# Setup end


class MyApi(Resource):
    def __init__(self, mongo_client):
        self.mongo = mongo_client

    @set_responses(ResponseModel)
    def get(self):
        return "Done"

    @set_responses(ResponseModel, 200)
    def put(self):
        return "Redone"

    @set_responses(
        ResponseModel,
        201,
        {
            409: {
                "description": "The path can't be found",
                "model": ResourceAlreadyExistsModel,
            }
        },
    )
    def post(self, res: ResourceModel):
        if self.mongo.is_resource_exist(res.name):
            return JSONResponse(409, content={"is_found": true})
        return "Done again"

Additional information about responses can be found here

@set_responses also support kwargs of the original function which includes different response classes and more!