MDNS requires a dash in hostname?

[ThomasJRyan]

CircuitPython version

Adafruit CircuitPython 8.2.1 on 2023-07-25; Raspberry Pi Pico W with rp2040

Code/REPL

import mdns
import socketpool
import wifi

from adafruit_httpserver import Server, Request, FileResponse


mdns_server = mdns.Server(wifi.radio)
mdns_server.hostname = "helloworld"
mdns_server.advertise_service(service_type="_http", protocol="_tcp", port=80)

pool = socketpool.SocketPool(wifi.radio)
server = Server(pool, "/static", debug=True)

wifi.radio.connect(
                ssid="<redacted>",
                password="<redacted>",
            )

@server.route("/")
def base(request: Request):
    """
    Serve the default index.html file.
    """
    return FileResponse(request, "index.html", "/www")


server.serve_forever(str(wifi.radio.ipv4_address))

Behavior

No error messages.

I am unable to connect to http://helloworld.local

Description

When I set the hostname to something without a dash such as helloworld MDNS does not seem to work correctly and I am unable to connect to http://helloworld.local

However, when I change it to something like hello-world then suddenly I am now able to connect to http://hello-world.local

Additional information

No response

[anecdata]

Is web workflow enabled via a settings.toml file?

Does it make a difference if wifi.radio.connect is moved before mdns_server.advertise_service?

[ThomasJRyan]

I did see the other issue that mentioned web workflow. I've tried completely erasing the contents of my settings.toml along with deleting it entirely and had the same issues. As far as I'm aware I'm not using the web workflow at all but I could still be missing something.

I've tried moving it before, after, inside functions, outside functions and the conclusion I came to was that if I put mdns_server.advertise_service inside of an async function then it won't work at all, but if I put it at the top of my file outside of any functions it will work, albeit still with this dash requirement

[anecdata]

Cool, as long as CIRCUITPY_WIFI_SSID / CIRCUITPY_WIFI_SSID aren't in settings.toml, there won't be a conflict of two MDNS servers using _http._tcp..