ComfyUI-Prompt-Calibrator/agent_bridge.py

#!/usr/bin/env python3
"""
agent_bridge.py — drive one calibration iteration from a CLI agent.

The external agent (controller/brain) calls this once per loop step:

    python agent_bridge.py \
        --workflow workflow_api.json \
        --prompt "1 woman, red lingerie, bedroom, full body, warm light" \
        --run-tag iter003 \
        --analysis-dir /path/to/ComfyUI/output/calibrator

It injects the prompt into the `CalibratorPromptReceptor` node, queues the graph
on a running ComfyUI (`POST /prompt`), waits for completion (`GET /history/{id}`),
then prints the Qwen3-VL Judge's analysis JSON to stdout for the agent to read.

Stdlib only — no third-party deps, so any agent can shell out to it.

Loop, from the agent's side:
    1. build a prompt (calibrate from the previous analysis)
    2. run this script -> capture stdout (the analysis JSON)
    3. read overall_score + per-axis {score, ref, gen}
    4. adjust the prompt and go to 1, until overall_score >= target
"""

from __future__ import annotations

import argparse
import json
import os
import sys
import time
import urllib.error
import urllib.request
import uuid

RECEPTOR_CLASS = "CalibratorPromptReceptor"
JUDGE_CLASS = "QwenVLImageJudge"


def _http_json(url: str, payload: dict | None = None, timeout: int = 30):
    data = json.dumps(payload).encode("utf-8") if payload is not None else None
    req = urllib.request.Request(
        url, data=data, headers={"Content-Type": "application/json"} if data else {})
    with urllib.request.urlopen(req, timeout=timeout) as resp:
        body = resp.read().decode("utf-8")
    return json.loads(body) if body else {}


def _inject(graph: dict, prompt: str, negative: str, seed: int, run_tag: str, mode: str):
    """Set the receptor's prompt/seed and the judge's mode/run_tag in-place.

    compare mode needs a receptor (to inject the prompt). describe mode is the first
    pass over the reference only, so no receptor is required."""
    found_receptor = False
    for node in graph.values():
        ctype = node.get("class_type")
        inputs = node.setdefault("inputs", {})
        if ctype == RECEPTOR_CLASS:
            inputs["prompt"] = prompt
            inputs["negative"] = negative
            inputs["seed"] = int(seed)
            found_receptor = True
        elif ctype == JUDGE_CLASS:
            inputs["mode"] = mode
            inputs["run_tag"] = run_tag
            inputs["prompt_used"] = prompt
    if mode == "compare" and not found_receptor:
        raise SystemExit(
            f"[agent_bridge] no '{RECEPTOR_CLASS}' node in the workflow — add the "
            f"'SxCP External Prompt (Receptor)' node and feed the sampler from it.")


def _wait_for_history(server: str, prompt_id: str, timeout: int):
    deadline = time.time() + timeout
    while time.time() < deadline:
        hist = _http_json(f"http://{server}/history/{prompt_id}")
        if prompt_id in hist:
            entry = hist[prompt_id]
            status = entry.get("status", {})
            # ComfyUI marks completed=True (or status_str) when the run is done.
            if status.get("completed", True):
                return entry
        time.sleep(1.0)
    raise SystemExit(f"[agent_bridge] timed out after {timeout}s waiting for {prompt_id}")


def _read_report(analysis_file: str, analysis_dir: str, run_tag: str):
    candidates = []
    if analysis_file:
        candidates.append(analysis_file)
    if analysis_dir:
        if run_tag:
            safe = "".join(c if c.isalnum() or c in "._-" else "_" for c in run_tag)
            candidates.append(os.path.join(analysis_dir, f"calib_{safe}.json"))
        candidates.append(os.path.join(analysis_dir, "latest.json"))
    for path in candidates:
        if os.path.isfile(path):
            with open(path, "r", encoding="utf-8") as f:
                return json.load(f), path
    return None, None


def main(argv=None):
    ap = argparse.ArgumentParser(description="Drive one ComfyUI calibration iteration.")
    ap.add_argument("--server", default="127.0.0.1:8188")
    ap.add_argument("--workflow", required=True, help="API-format workflow JSON")
    ap.add_argument("--mode", choices=["compare", "describe"], default="compare",
                    help="describe = first pass over the reference only (no prompt needed)")
    ap.add_argument("--prompt", default="", help="generation prompt (required for compare)")
    ap.add_argument("--negative", default="")
    ap.add_argument("--seed", type=int, default=0)
    ap.add_argument("--run-tag", default="")
    ap.add_argument("--analysis-file", default="",
                    help="explicit path to the report JSON the Judge writes")
    ap.add_argument("--analysis-dir", default="",
                    help="dir holding calib_<tag>.json / latest.json (Judge report_dir)")
    ap.add_argument("--timeout", type=int, default=600)
    args = ap.parse_args(argv)

    if args.mode == "compare" and not args.prompt:
        raise SystemExit("[agent_bridge] --prompt is required in compare mode.")

    with open(args.workflow, "r", encoding="utf-8") as f:
        graph = json.load(f)

    _inject(graph, args.prompt, args.negative, args.seed, args.run_tag, args.mode)

    client_id = uuid.uuid4().hex
    try:
        queued = _http_json(f"http://{args.server}/prompt",
                            {"prompt": graph, "client_id": client_id})
    except urllib.error.URLError as e:
        raise SystemExit(f"[agent_bridge] cannot reach ComfyUI at {args.server}: {e}")
    prompt_id = queued.get("prompt_id")
    if not prompt_id:
        raise SystemExit(f"[agent_bridge] queue rejected: {json.dumps(queued)[:400]}")

    _wait_for_history(args.server, prompt_id, args.timeout)

    report, path = _read_report(args.analysis_file, args.analysis_dir, args.run_tag)
    if report is None:
        raise SystemExit(
            "[agent_bridge] run finished but no report file found. Set the Judge "
            "node's report_dir and pass --analysis-dir (or --analysis-file).")

    report["_prompt_id"] = prompt_id
    report["_report_path"] = path
    json.dump(report, sys.stdout, ensure_ascii=False, indent=2)
    sys.stdout.write("\n")
    return 0


if __name__ == "__main__":
    raise SystemExit(main())