z4j-fastapi 1.2.0

z4j FastAPI framework adapter (Apache 2.0)

z4j-fastapi

License: Apache 2.0

FastAPI framework adapter for z4j. Integrates via FastAPI's lifespan hook - one context manager wraps the agent's lifecycle with your app's startup and shutdown.

Install

Pick your task engine and install with the matching extra. Each extra pulls the engine adapter AND its companion scheduler in one shot, so a fresh install never needs a second command.

pip install z4j-fastapi[arq]        # arq + arq-cron (async-native, recommended)
pip install z4j-fastapi[taskiq]     # TaskIQ + taskiq-scheduler (async, broker-flexible)
pip install z4j-fastapi[celery]     # Celery + celery-beat (sync stack)
pip install z4j-fastapi[rq]         # RQ + rq-scheduler
pip install z4j-fastapi[dramatiq]   # Dramatiq + APScheduler
pip install z4j-fastapi[huey]       # Huey + huey-periodic
pip install z4j-fastapi[all]        # every engine (CI / kitchen sink)

pip install z4j-fastapi (no extra) installs only the framework adapter. That's useful if you already manage engine packages elsewhere; otherwise always pick an engine extra.

Configure

Mount the z4j lifespan in your FastAPI app:

from contextlib import asynccontextmanager
from fastapi import FastAPI
from z4j_fastapi import Z4JLifespan

z4j = Z4JLifespan(
    brain_url="https://z4j.internal",
    token="z4j_agent_...",        # minted in the brain dashboard
    project_id="my-project",
)

@asynccontextmanager
async def lifespan(app: FastAPI):
    async with z4j(app):
        yield

app = FastAPI(lifespan=lifespan)

Or, if you have no other lifespan logic:

from z4j_fastapi import Z4JLifespan

app = FastAPI(lifespan=Z4JLifespan(
    brain_url="https://z4j.internal",
    token="z4j_agent_...",
    project_id="my-project",
))

On uvicorn startup the agent connects to the brain and z4j's dashboard populates with every arq / Celery / Dramatiq / taskiq / Huey task your workers register.

What it does

Piece	Purpose
Z4JLifespan(...)	Async context manager matching FastAPI's lifespan contract
Graceful shutdown	Flushes the event buffer on await lifespan.aclose()
Async-native	Uses asyncio.create_task - never blocks the event loop

Reliability

z4j-fastapi follows the project-wide safety rule: z4j never breaks your FastAPI app. Agent failures are caught at the boundary and never propagate into your request handlers.

Documentation

• Quickstart (FastAPI)
• Install guide
• Architecture

License

Apache 2.0 - see LICENSE. Your FastAPI application is never AGPL-tainted by importing z4j_fastapi.

Links

• Homepage: https://z4j.com
• Documentation: https://z4j.dev
• Issues: https://github.com/z4jdev/z4j-fastapi/issues
• Changelog: CHANGELOG.md
• Security: [e-mail] (see SECURITY.md)