ComfyUI/custom_nodes/ComfyUI-Custom-Scripts/py/model_info.py

import hashlib
import json
from aiohttp import web
from server import PromptServer
import folder_paths
import os


def get_metadata(filepath):
    with open(filepath, "rb") as file:
        # https://github.com/huggingface/safetensors#format
        # 8 bytes: N, an unsigned little-endian 64-bit integer, containing the size of the header
        header_size = int.from_bytes(file.read(8), "little", signed=False)

        if header_size <= 0:
            raise BufferError("Invalid header size")

        header = file.read(header_size)
        if header_size <= 0:
            raise BufferError("Invalid header")

        header_json = json.loads(header)
        return header_json["__metadata__"] if "__metadata__" in header_json else None


@PromptServer.instance.routes.post("/pysssss/metadata/notes/{name}")
async def save_notes(request):
    name = request.match_info["name"]
    pos = name.index("/")
    type = name[0:pos]
    name = name[pos+1:]

    file_path = None
    if type == "embeddings" or type == "loras":
        name = name.lower()
        files = folder_paths.get_filename_list(type)
        for f in files:
            lower_f = f.lower()
            if lower_f == name:
                file_path = folder_paths.get_full_path(type, f)
            else:
                n = os.path.splitext(f)[0].lower()
                if n == name:
                    file_path = folder_paths.get_full_path(type, f)

            if file_path is not None:
                break
    else:
        file_path = folder_paths.get_full_path(
            type, name)
    if not file_path:
        return web.Response(status=404)

    file_no_ext = os.path.splitext(file_path)[0]
    info_file = file_no_ext + ".txt"
    with open(info_file, "w") as f:
        f.write(await request.text())

    return web.Response(status=200)


@PromptServer.instance.routes.get("/pysssss/metadata/{name}")
async def load_metadata(request):
    name = request.match_info["name"]
    pos = name.index("/")
    type = name[0:pos]
    name = name[pos+1:]

    file_path = None
    if type == "embeddings" or type == "loras":
        name = name.lower()
        files = folder_paths.get_filename_list(type)
        for f in files:
            lower_f = f.lower()
            if lower_f == name:
                file_path = folder_paths.get_full_path(type, f)
            else:
                n = os.path.splitext(f)[0].lower()
                if n == name:
                    file_path = folder_paths.get_full_path(type, f)

            if file_path is not None:
                break
    else:
        file_path = folder_paths.get_full_path(
            type, name)
    if not file_path:
        return web.Response(status=404)

    try:
        meta = get_metadata(file_path)
    except:
        meta = None

    if meta is None:
        meta = {}

    file_no_ext = os.path.splitext(file_path)[0]

    info_file = file_no_ext + ".txt"
    if os.path.isfile(info_file):
        with open(info_file, "r") as f:
            meta["pysssss.notes"] = f.read()

    hash_file = file_no_ext + ".sha256"
    if os.path.isfile(hash_file):
        with open(hash_file, "rt") as f:
            meta["pysssss.sha256"] = f.read()
    else:
        with open(file_path, "rb") as f:
            meta["pysssss.sha256"] = hashlib.sha256(f.read()).hexdigest()
        with open(hash_file, "wt") as f:
            f.write(meta["pysssss.sha256"])

    return web.json_response(meta)