"""FastAPI control surface for the agent (served on localhost).
Start / stop the worker pool, tune the worker count live (trades desktop
responsiveness for throughput), and watch GPU load + progress + the server-side
queue. Config is env-seeded; the worker count is adjustable here on the fly.
"""
from fastapi import FastAPI, Request
from fastapi.responses import HTMLResponse, JSONResponse
from . import logbuf
from .config import Config
from .gpu import read_gpu
from .worker import Worker
logbuf.install()
cfg = Config.from_env()
worker = Worker(cfg)
app = FastAPI(title="FabledCurator GPU agent")
@app.middleware("http")
async def _no_store(request, call_next):
# The control page is a static string and the status/gpu/logs polls are
# live data — never let the browser cache either, or a freshly-pulled agent
# image still shows the OLD UI until a hard refresh (operator-flagged
# 2026-06-30).
resp = await call_next(request)
resp.headers["Cache-Control"] = "no-store"
return resp
@app.on_event("startup")
def _maybe_autostart() -> None:
# With AUTO_START set, a container restart (host reboot, or `restart:
# unless-stopped` after a crash) resumes the worker on its own — the slots
# then ride out a still-down curator via lease backoff. Lets the agent
# survive a redeploy with nobody at the desktop to click Start.
if cfg.auto_start and cfg.token:
worker.start()
@app.get("/", response_class=HTMLResponse)
def index() -> str:
return _PAGE
@app.post("/start")
def start():
worker.start()
return JSONResponse(worker.status())
@app.post("/stop")
def stop():
worker.stop()
return JSONResponse(worker.status())
@app.post("/concurrency")
async def concurrency(request: Request):
body = await request.json()
worker.set_concurrency(int(body.get("value", 1)))
return JSONResponse(worker.status())
@app.post("/auto")
async def auto(request: Request):
body = await request.json()
worker.set_auto(bool(body.get("value", True)))
return JSONResponse(worker.status())
@app.get("/gpu")
def gpu():
# GPU meters poll this on their own fast cadence. It only reads local
# nvidia-smi — no curator round-trip — so the util/VRAM bars stay live even
# when /status is slow waiting on the (sometimes busy) curator queue call.
return JSONResponse(read_gpu() or {})
@app.get("/logs")
def logs():
return JSONResponse({"lines": list(logbuf.LINES)})
@app.get("/status")
def status():
s = worker.status()
s["fc_url"] = cfg.fc_url
s["configured"] = bool(cfg.token)
# GPU is served by /gpu (cached); /status stays light so Start/Stop never
# queue behind it.
try:
s["queue"] = worker.client.queue_status()
except Exception:
s["queue"] = None
return JSONResponse(s)
_PAGE = """
FabledCurator · GPU agent
◆ FabledCurator GPU agent
—
Server — · token —
curator unreachable — holding work + retrying, resumes on its own (no restart needed)