Flask decorator for Netbox webhook authentication

import hmac
from functools import wraps
from flask import request, current_app, abort


def check_netbox_auth(f):
    @wraps(f)
    def decorated(*args, **kwargs):
        x_hook_signature = request.headers.get('X-Hook-Signature', None)
        content_length = int(request.headers.get('Content-Length', 0))

        if content_length > 1_000_000:
            # To prevent memory allocation attacks
            abort(400, "Content too long")

        if x_hook_signature:
            # Check signature
            raw_input = request.data
            input_hmac = hmac.new(key=current_app.config['NETBOX_SECRET'].encode(), msg=raw_input, digestmod="sha512")
            if not hmac.compare_digest(input_hmac.hexdigest(), x_hook_signature):
                abort(400, "Invalid message signature")
        else:
            abort(400, "No message signature to check")
        return f(*args, **kwargs)

    return decorated

from flask import Flask, request
from netbox_wrapper import check_netbox_auth

app = Flask(__name__)

# define your shared secret
app.config['NETBOX_SECRET'] = "secret"

@app.route("/netbox_webhook", methods=['POST'])
@check_netbox_auth
def netbox_hook():
    print(request.json)
    return {"status":"ok"}


if __name__ == "__main__":
    app.run(host='0.0.0.0', port=6666)