main.py

from fastapi import FastAPI, Request
from fastapi.staticfiles import StaticFiles
from fastapi.responses import HTMLResponse
from itables import to_html_datatable
from pathlib import Path
import pandas as pd


ROOT = Path("/home/user")
app = FastAPI()
app.mount(path="/files", app=StaticFiles(directory=ROOT), name="HOME")


@app.middleware("http")
async def file_system(request: Request, call_next):
    url = request.url
    if url.path.endswith("/"):
        return HTMLResponse(
            content=files_in_folder(url.path.lstrip("/files"))
        )
    response = await call_next(request)
    return response


def files_in_folder(path: str):
    """List files to render as file index."""

    folder = ROOT / path
    folder_glob = folder.glob("*")
    res = pd.DataFrame(
        [
            (
                f.name,
                f.stat().st_size,
                pd.Timestamp(int(f.stat().st_mtime), unit="s"),
                f.is_dir(),
            )
            for f in folder_glob
        ],
        columns=["path", "size", "mtime", "is_dir"],
    )

    res["path"] = res.apply(
        lambda x: f"<a href=/files/{path}{x.path}{'/' if x.is_dir else ''}>{x.path}</a>",
        axis=1,
    )

    if folder != ROOT:  # create ".." unless in ROOT
        if "/" in path[:-1]:
            parent_path = path.rsplit("/", 2)[0]
            parent_url = f"/files/{parent_path}/"
        else:
            parent_url = "/"
        res.loc[-1] = [f"<a href={parent_url}>..</a>", "", "", 2]

    res.sort_values(["is_dir", "path"], ascending=[False, True], inplace=True)

    table = to_html_datatable(
        df=res.drop(columns="is_dir"),
        classes="display nowrap compact",
        showIndex=False,
        paging=False,
    )

    return f"""
    <div style="width:50%; margin: 0 auto;">
        <h1>{folder}</h1><br>
        {table}
    </div>
    """