main.py

import json
import subprocess
import os
from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
from fastapi.responses import HTMLResponse
from pydantic import BaseModel
from decouple import config


ASSET_REG_URL: str = config("ASSET_REG_URL", default="https://assets.blockstream.info")
WELL_KNOWN_FOLDER: str = config("WELL_KNOWN_FOLDER", default="/var/www/html/.well-known")


app = FastAPI()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

app.mount("/.well-known", StaticFiles(directory=f"{WELL_KNOWN_FOLDER}"), name="well-known")


templates = Jinja2Templates(directory="templates")


class RegisterRequest(BaseModel):
    asset_id: str
    contract: dict


@app.get("/health")
def health():
    return {"health": "ok"}


@app.get("/.well-known", response_class=HTMLResponse)
def list_files(request: Request):
    files = os.listdir(f"{WELL_KNOWN_FOLDER}")
    files_paths = sorted([f"{request.url._url}/{f}" for f in files])
    return templates.TemplateResponse(
        "list_files.html", {"request": request, "files": files_paths}
    )


@app.post("/register_asset", status_code=201)
async def register_asset_id(request_body: RegisterRequest, request: Request):
    print(f" request_body: { request_body }")
    print(f" TYPE : {isinstance(request_body.contract, dict)}")
    print(f" TYPE : {isinstance(request_body.contract, str)}")
    if register_asset_id_local(request_body.asset_id, str(request.url.netloc)):
        print(f"File succesffully written: {request_body.asset_id}")
    register_asset_id_on_liquid(request_body.asset_id, request_body.contract)
    return {"asset_id": request_body.asset_id}


def register_asset_id_local(asset_id: str, netloc: str):
    try:
        f = open(f"{WELL_KNOWN_FOLDER}/liquid-asset-proof-" + asset_id, "w")
        f.write("Authorize linking the domain name " + netloc + " to the Liquid asset " + asset_id)
        f.close()
    except Exception as e:
        print(f"File Write execption: {e}")
        return False
    return True


def schedule_task(task_array: list):
    register_response = subprocess.run(task_array, stdout=subprocess.PIPE)
    if register_response.returncode == 0:
        print(register_response.stdout.decode("ASCII"))
    else:
        print(register_response.returncode)


def register_asset_id_on_liquid(asset_id: str, contract: dict):
    contract = json.dumps(contract)
    input_json = f'{{"asset_id":"{asset_id}","contract":{contract}}}'
    register_request = [
        "tsp",
        "curl",
        f"{ASSET_REG_URL}",
        "-H",
        "Content-Type: application/json",
        "-d",
        f"{input_json}",
    ]
    schedule_task(["tsp", "sleep", "15m"])
    schedule_task(register_request)