Background Tasks

In this section, you'll learn how to run background tasks in Ravyn, allowing you to perform non-blocking operations after sending a response.

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What are Background Tasks?

Background tasks are functions that run asynchronously after the response is returned to the client.

They're perfect for:

• Sending emails
• Writing logs
• Triggering external webhooks
• Cleanup operations

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Using BackgroundTask

Ravyn provides a simple interface for background execution:

from ravyn import BackgroundTask, get

async def notify_user(email: str):
    # Imagine this sends an email
    await some_email_function(email)

@get("/send-notification", background=BackgroundTask(notify_user, "user@example.com"))
def send_notification() -> dict:
    return {
        "message": "Scheduled"
    }

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Using BackgroundTasks for Multiple Tasks

You can queue multiple tasks with BackgroundTasks:

from ravyn import BackgroundTasks, post

async def cleanup(file_path: str):
    await remove_file(file_path)

async def log_event(event_id: int):
    await save_log(event_id)

@post("/submit", background=BackgroundTasks(
    tasks=[
        BackgroundTask(cleanup, "/tmp/tempfile"),
        BackgroundTask(log_event, 42),
    ]
))
def submit(background: BackgroundTasks) -> dict:
    return {"status": "submitted"}

You can also pass background tasks via response classes:

from ravyn import Ravyn, post, BackgroundTask, BackgroundTasks
from ravyn.responses import JSONResponse

def send_email(to: str):
    print(f"Email sent to {to}")

def log_event(event: str):
    print(f"Event logged: {event}")

@post("/register")
def register(email: str) -> JSONResponse:
    # Create multiple background tasks
    tasks = BackgroundTasks(tasks=[
        BackgroundTask(send_email, email),
        BackgroundTask(log_event, "user_registered")
    ])

    # Pass tasks via response
    return JSONResponse(
        {"registered": email},
        background=tasks
    )

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Sync vs Async Tasks

Background tasks can be either synchronous or asynchronous. Both are supported.

def write_log_sync():
    with open("log.txt", "a") as f:
        f.write("Log entry\n")

@get("/log", background=BackgroundTasks(
    tasks=[
        BackgroundTask(write_log_sync)
    ]
))
def log():
    return {"message": "logged"}

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What's Next?

You've now learned how to:

• Add and run background tasks
• Combine multiple tasks
• Mix sync and async behavior

👉 Next up: dependencies . learn how to use Inject, Injects, and shared state across your app.