IFastAPI

Running fastapi under uvicorn inside IPython

import os, asyncio, uvicorn, fastapi, pydantic, IPython, ujson, tornado.ioloop

Hubba Hubba

port = 8000
app_args = {}
uvi_args = dict(port=port)
IN_HUB = "JUPYTERHUB_SERVICE_PREFIX" in os.environ
prefix = "/"
if IN_HUB:
    prefix = f"""{os.environ["JUPYTERHUB_SERVICE_PREFIX"]}proxy/{port}"""
    app_args.update(openapi_prefix=prefix)
    uvi_args.update(root_path=prefix)

Make an App

app = fastapi.FastAPI(title="IFastAPI", **app_args)

Make a route

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

Serve in-loop with uvicorn

config = uvicorn.Config(app, **uvi_args)
server = uvicorn.Server(config=config)

The actual serving will live in an asyncio.Task

if __name__ == "__main__":
    task = asyncio.ensure_future(server.serve())

Inspecting the route

def show_route(route, height="400px"):
    url = f"{prefix}{route}" if IN_HUB else f"http://localhost:{port}{route}"
    display(IPython.display.Markdown(f"[`{url}`]({url})"))
    display(IPython.display.IFrame(url, width="100%", height=height))
show_route("/", height="40px")

Live: Modelling the domain

class Item(pydantic.BaseModel):
    """
    a lovely model
    """
    name: str
    price: float
    is_offer: bool = None
IPython.display.JSON(ujson.loads(Item.schema_json()))

DB = {}

Live: using the domain

@app.get("/items/{item_id}", response_model=Item)
def read_item(item_id: int, q: str = None) -> Item:
    return DB[item_id]

@app.put("/items/{item_id}")
def create_item(item_id: int, item: Item):
    DB[item_id] = item
    return {"item_name": item.name, "item_id": item_id}

# openapi gets cached, force reloading it
app.openapi_schema = None

Showing Docs

show_route("/docs")

Showing (More) Docs

show_route("/redoc")

All done

if __name__ == "__main__":
    tornado.ioloop.IOLoop.current().add_callback(server.shutdown)