Files
psyc/scripts/serve_model.py
m17hr1l 2a9c0bf34a stage-6: model inference server
scripts/serve_model.py — FastAPI in the CUDA container, loads base Qwen3.5-4B
+ a psyc adapter once and serves POST /infer. Lets the cockpit (no torch in
its venv) put a real fine-tuned model behind a Worker Mesh bot over HTTP.
Dockerfile.train gains a fastapi + uvicorn layer.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-18 21:05:16 +02:00

89 lines
3.0 KiB
Python

"""psyc model inference server — loads a psyc adapter once, serves /infer over HTTP.
Run inside the CUDA container (keeps the model resident, serves many requests):
docker run --gpus all --rm -p 8771:8771 --entrypoint python \
-v $(pwd)/data:/data -v $(pwd)/scripts:/scripts \
psyc-trainer /scripts/serve_model.py --adapter /data/adapters/psyc-v4/final
The cockpit (which has no torch) calls this over HTTP to put a real fine-tuned
model behind a Worker Mesh bot.
"""
from __future__ import annotations
# unsloth must be imported BEFORE transformers.
from unsloth import FastLanguageModel # noqa: I001
import argparse
import re
import uvicorn
from fastapi import FastAPI
from pydantic import BaseModel
def strip_think(text: str) -> str:
"""Drop Qwen3.5 thinking-mode blocks so the caller gets just the answer."""
return re.sub(r"<think>.*?</think>\s*", "", text, flags=re.DOTALL).strip()
class InferRequest(BaseModel):
instruction: str
input: str
max_new_tokens: int = 256
class InferResponse(BaseModel):
output: str
adapter: str
def build_app(model: object, tokenizer: object, adapter: str) -> FastAPI:
app = FastAPI(title="psyc inference server", version="0.1.0")
@app.get("/healthz")
def healthz() -> dict:
return {"status": "ok", "adapter": adapter}
@app.post("/infer", response_model=InferResponse)
def infer(req: InferRequest) -> InferResponse:
prompt = f"{req.instruction}\n\n{req.input}"
messages = [{"role": "user", "content": [{"type": "text", "text": prompt}]}]
inputs = tokenizer.apply_chat_template(
messages,
tokenize=True,
add_generation_prompt=True,
return_tensors="pt",
enable_thinking=False,
).to(model.device)
out = model.generate(input_ids=inputs, max_new_tokens=req.max_new_tokens, do_sample=False)
generated = strip_think(tokenizer.decode(out[0][inputs.shape[1]:], skip_special_tokens=True))
return InferResponse(output=generated, adapter=adapter)
return app
def main() -> None:
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument("--adapter", required=True, help="path to adapter final/ dir")
parser.add_argument("--base-model", default="unsloth/Qwen3.5-4B")
parser.add_argument("--host", default="0.0.0.0")
parser.add_argument("--port", type=int, default=8771)
parser.add_argument("--max-seq-length", type=int, default=4096)
args = parser.parse_args()
model, tokenizer = FastLanguageModel.from_pretrained(
model_name=args.adapter,
max_seq_length=args.max_seq_length,
dtype=None,
load_in_4bit=True,
)
FastLanguageModel.for_inference(model)
app = build_app(model, tokenizer, args.adapter)
print(f"[psyc-serve] model ready — adapter {args.adapter}, listening on {args.host}:{args.port}")
uvicorn.run(app, host=args.host, port=args.port, log_level="warning")
if __name__ == "__main__":
main()