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🔆 🎉

👆 💪 🔬 ⚛ (📟) 👈 🔜 🛠️ ⏭ 🈸 ▶️ 🆙. 👉 ⛓ 👈 👉 📟 🔜 🛠️ 🕐, 🈸 ▶️ 📨 📨.

🎏 🌌, 👆 💪 🔬 ⚛ (📟) 👈 🔜 🛠️ 🕐❔ 🈸 🤫 🔽. 👉 💼, 👉 📟 🔜 🛠️ 🕐, ⏮️ ✔️ 🍵 🎲 📚 📨.

↩️ 👉 📟 🛠️ ⏭ 🈸 ▶️ ✊ 📨, & ▶️️ ⏮️ ⚫️ 🏁 🚚 📨, ⚫️ 📔 🎂 🈸 🔆 (🔤 "🔆" 🔜 ⚠ 🥈 👶).

👉 💪 📶 ⚠ ⚒ 🆙 👈 👆 💪 ⚙️ 🎂 📱, & 👈 💰 👪 📨, &/⚖️ 👈 👆 💪 🧹 🆙 ⏮️. 🖼, 💽 🔗 🎱, ⚖️ 🚚 🔗 🎰 🏫 🏷.

⚙️ 💼

➡️ ▶️ ⏮️ 🖼 ⚙️ 💼 & ⤴️ 👀 ❔ ❎ ⚫️ ⏮️ 👉.

➡️ 🌈 👈 👆 ✔️ 🎰 🏫 🏷 👈 👆 💚 ⚙️ 🍵 📨. 👶

🎏 🏷 🔗 👪 📨,, ⚫️ 🚫 1️⃣ 🏷 📍 📨, ⚖️ 1️⃣ 📍 👩‍💻 ⚖️ 🕳 🎏.

➡️ 🌈 👈 🚚 🏷 💪 ✊ 🕰, ↩️ ⚫️ ✔️ ✍ 📚 💽 ⚪️➡️ 💾. 👆 🚫 💚 ⚫️ 🔠 📨.

👆 💪 📐 ⚫️ 🔝 🎚 🕹/📁, ✋️ 👈 🔜 ⛓ 👈 ⚫️ 🔜 📐 🏷 🚥 👆 🏃‍♂ 🙅 🏧 💯, ⤴️ 👈 💯 🔜 🐌 ↩️ ⚫️ 🔜 ✔️ ⌛ 🏷 📐 ⏭ 💆‍♂ 💪 🏃 🔬 🍕 📟.

👈 ⚫️❔ 👥 🔜 ❎, ➡️ 📐 🏷 ⏭ 📨 🍵, ✋️ 🕴 ▶️️ ⏭ 🈸 ▶️ 📨 📨, 🚫 ⏪ 📟 ➖ 📐.

🔆

👆 💪 🔬 👉 🕴 & 🤫 ⚛ ⚙️ lifespan 🔢 FastAPI 📱, & "🔑 👨‍💼" (👤 🔜 🎦 👆 ⚫️❔ 👈 🥈).

➡️ ▶️ ⏮️ 🖼 & ⤴️ 👀 ⚫️ ℹ.

👥 ✍ 🔁 🔢 lifespan() ⏮️ yield 💖 👉:

from contextlib import asynccontextmanager

from fastapi import FastAPI


def fake_answer_to_everything_ml_model(x: float):
    return x * 42


ml_models = {}


@asynccontextmanager
async def lifespan(app: FastAPI):
    # Load the ML model
    ml_models["answer_to_everything"] = fake_answer_to_everything_ml_model
    yield
    # Clean up the ML models and release the resources
    ml_models.clear()


app = FastAPI(lifespan=lifespan)


@app.get("/predict")
async def predict(x: float):
    result = ml_models["answer_to_everything"](x)
    return {"result": result}

📥 👥 ⚖ 😥 🕴 🛠️ 🚚 🏷 🚮 (❌) 🏷 🔢 📖 ⏮️ 🎰 🏫 🏷 ⏭ yield. 👉 📟 🔜 🛠️ 🈸 ▶️ ✊ 📨, ⏮️ 🕴.

& ⤴️, ▶️️ ⏮️ yield, 👥 🚚 🏷. 👉 📟 🔜 🛠️ ⏮️ 🈸 🏁 🚚 📨, ▶️️ ⏭ 🤫. 👉 💪, 🖼, 🚀 ℹ 💖 💾 ⚖️ 💻.

Tip

shutdown 🔜 🔨 🕐❔ 👆 ⛔️ 🈸.

🎲 👆 💪 ▶️ 🆕 ⏬, ⚖️ 👆 🤚 🎡 🏃 ⚫️. 🤷

🔆 🔢

🥇 👜 👀, 👈 👥 ⚖ 🔁 🔢 ⏮️ yield. 👉 📶 🎏 🔗 ⏮️ yield.

from contextlib import asynccontextmanager

from fastapi import FastAPI


def fake_answer_to_everything_ml_model(x: float):
    return x * 42


ml_models = {}


@asynccontextmanager
async def lifespan(app: FastAPI):
    # Load the ML model
    ml_models["answer_to_everything"] = fake_answer_to_everything_ml_model
    yield
    # Clean up the ML models and release the resources
    ml_models.clear()


app = FastAPI(lifespan=lifespan)


@app.get("/predict")
async def predict(x: float):
    result = ml_models["answer_to_everything"](x)
    return {"result": result}

🥇 🍕 🔢, ⏭ yield, 🔜 🛠️ 🈸 ▶️.

& 🍕 ⏮️ yield 🔜 🛠️ ⏮️ 🈸 ✔️ 🏁.

🔁 🔑 👨‍💼

🚥 👆 ✅, 🔢 🎀 ⏮️ @asynccontextmanager.

👈 🗜 🔢 🔘 🕳 🤙 "🔁 🔑 👨‍💼".

from contextlib import asynccontextmanager

from fastapi import FastAPI


def fake_answer_to_everything_ml_model(x: float):
    return x * 42


ml_models = {}


@asynccontextmanager
async def lifespan(app: FastAPI):
    # Load the ML model
    ml_models["answer_to_everything"] = fake_answer_to_everything_ml_model
    yield
    # Clean up the ML models and release the resources
    ml_models.clear()


app = FastAPI(lifespan=lifespan)


@app.get("/predict")
async def predict(x: float):
    result = ml_models["answer_to_everything"](x)
    return {"result": result}

🔑 👨‍💼 🐍 🕳 👈 👆 💪 ⚙️ with 📄, 🖼, open() 💪 ⚙️ 🔑 👨‍💼:

with open("file.txt") as file:
    file.read()

⏮️ ⏬ 🐍, 📤 🔁 🔑 👨‍💼. 👆 🔜 ⚙️ ⚫️ ⏮️ async with:

async with lifespan(app):
    await do_stuff()

🕐❔ 👆 ✍ 🔑 👨‍💼 ⚖️ 🔁 🔑 👨‍💼 💖 🔛, ⚫️❔ ⚫️ 🔨 👈, ⏭ 🛬 with 🍫, ⚫️ 🔜 🛠️ 📟 ⏭ yield, & ⏮️ ❎ with 🍫, ⚫️ 🔜 🛠️ 📟 ⏮️ yield.

👆 📟 🖼 🔛, 👥 🚫 ⚙️ ⚫️ 🔗, ✋️ 👥 🚶‍♀️ ⚫️ FastAPI ⚫️ ⚙️ ⚫️.

lifespan 🔢 FastAPI 📱 ✊ 🔁 🔑 👨‍💼, 👥 💪 🚶‍♀️ 👆 🆕 lifespan 🔁 🔑 👨‍💼 ⚫️.

from contextlib import asynccontextmanager

from fastapi import FastAPI


def fake_answer_to_everything_ml_model(x: float):
    return x * 42


ml_models = {}


@asynccontextmanager
async def lifespan(app: FastAPI):
    # Load the ML model
    ml_models["answer_to_everything"] = fake_answer_to_everything_ml_model
    yield
    # Clean up the ML models and release the resources
    ml_models.clear()


app = FastAPI(lifespan=lifespan)


@app.get("/predict")
async def predict(x: float):
    result = ml_models["answer_to_everything"](x)
    return {"result": result}

🎛 🎉 (😢)

Warning

👍 🌌 🍵 🕴 & 🤫 ⚙️ lifespan 🔢 FastAPI 📱 🔬 🔛.

👆 💪 🎲 🚶 👉 🍕.

📤 🎛 🌌 🔬 👉 ⚛ 🛠️ ⏮️ 🕴 & ⏮️ 🤫.

👆 💪 🔬 🎉 🐕‍🦺 (🔢) 👈 💪 🛠️ ⏭ 🈸 ▶️ 🆙, ⚖️ 🕐❔ 🈸 🤫 🔽.

👫 🔢 💪 📣 ⏮️ async def ⚖️ 😐 def.

startup 🎉

🚮 🔢 👈 🔜 🏃 ⏭ 🈸 ▶️, 📣 ⚫️ ⏮️ 🎉 "startup":

from fastapi import FastAPI

app = FastAPI()

items = {}


@app.on_event("startup")
async def startup_event():
    items["foo"] = {"name": "Fighters"}
    items["bar"] = {"name": "Tenders"}


@app.get("/items/{item_id}")
async def read_items(item_id: str):
    return items[item_id]

👉 💼, startup 🎉 🐕‍🦺 🔢 🔜 🔢 🏬 "💽" ( dict) ⏮️ 💲.

👆 💪 🚮 🌅 🌘 1️⃣ 🎉 🐕‍🦺 🔢.

& 👆 🈸 🏆 🚫 ▶️ 📨 📨 ⏭ 🌐 startup 🎉 🐕‍🦺 ✔️ 🏁.

shutdown 🎉

🚮 🔢 👈 🔜 🏃 🕐❔ 🈸 🤫 🔽, 📣 ⚫️ ⏮️ 🎉 "shutdown":

from fastapi import FastAPI

app = FastAPI()


@app.on_event("shutdown")
def shutdown_event():
    with open("log.txt", mode="a") as log:
        log.write("Application shutdown")


@app.get("/items/")
async def read_items():
    return [{"name": "Foo"}]

📥, shutdown 🎉 🐕‍🦺 🔢 🔜 ✍ ✍ ⏸ "Application shutdown" 📁 log.txt.

Info

open() 🔢, mode="a" ⛓ "🎻",, ⏸ 🔜 🚮 ⏮️ ⚫️❔ 🔛 👈 📁, 🍵 📁 ⏮️ 🎚.

Tip

👀 👈 👉 💼 👥 ⚙️ 🐩 🐍 open() 🔢 👈 🔗 ⏮️ 📁.

, ⚫️ 🔌 👤/🅾 (🔢/🔢), 👈 🚚 "⌛" 👜 ✍ 💾.

✋️ open() 🚫 ⚙️ async & await.

, 👥 📣 🎉 🐕‍🦺 🔢 ⏮️ 🐩 def ↩️ async def.

Info

👆 💪 ✍ 🌅 🔃 👫 🎉 🐕‍🦺 💃 🎉' 🩺.

startup & shutdown 👯‍♂️

📤 ↕ 🤞 👈 ⚛ 👆 🕴 & 🤫 🔗, 👆 💪 💚 ▶️ 🕳 & ⤴️ 🏁 ⚫️, 📎 ℹ & ⤴️ 🚀 ⚫️, ♒️.

🔨 👈 👽 🔢 👈 🚫 💰 ⚛ ⚖️ 🔢 👯‍♂️ 🌅 ⚠ 👆 🔜 💪 🏪 💲 🌐 🔢 ⚖️ 🎏 🎱.

↩️ 👈, ⚫️ 🔜 👍 ↩️ ⚙️ lifespan 🔬 🔛.

📡 ℹ

📡 ℹ 😟 🤓. 👶

🔘, 🔫 📡 🔧, 👉 🍕 🔆 🛠️, & ⚫️ 🔬 🎉 🤙 startup & shutdown.

🎧 🈸

👶 ✔️ 🤯 👈 👫 🔆 🎉 (🕴 & 🤫) 🔜 🕴 🛠️ 👑 🈸, 🚫 🎧 🈸 - 🗻.