socket.gethostbyaddr

[verasativa]

Hi, how should I replace the socket.gethostbyaddr function from full python? (I'm running a hotspot and a wifi client networks)

[sophiedegran]

Hi
I think your asking for socket.getaddrinfo(host, port)[0][-1]

[verasativa]

I think that function return ip (and other data) from hostname and port. I need a reverse lookup, host from ip address.

[sophiedegran]

Ah ok!
It's something like that:

import socket
domain = "google.com"
ip = socket.getaddrinfo (domain, None)[0][-1][0]

Hope that help you

[verasativa]

Are you a bot?
I need to go from 192.168.0.1 to router.lan, that a reverse dns look up.
Not trying to be offensive, bet few local LLMs give me the same answer, that you did (just some sample of dns A lookup).

[sophiedegran]

Don't understand what's your problem...
If you are in AP mode you cannot go to your dns
If you are in STA mode you have define in the ifconfig your gateway and your dns server ...
if your gateway is not the dns server she should route dns request ...
It seem she doesn't...
Sorry but that's not a part of micropython ...

[Josverl]

If you are in AP mode you cannot go to your dns

That is possible when you run MicroPython-mdns on the AP itself.

https://github.com/cbrand/micropython-mdns

https://github.com/vshymanskyy/aiodns

Still, clients on that isolated network, will need to register names with the mDNS server.

[shariltumin]

Micropython only has socket.getaddrinfo; it does not have any others. You need to implement socket.gethostbyaddr using a low-level UDP DNS query on port 53 to a DNS server. Alternatively, you can use the web API.

# dns_web_api.py
import time
import wifi  # connect to your wifi
time.sleep(5)

import requests

def reverse_ip_to_ptr(ip):
    return '.'.join(ip.split('.')[::-1]) + '.in-addr.arpa'

# Forward DNS lookup example
domain = 'one.one.one.one'
print(domain)
forward_url = f'https://dns.google/resolve?name={domain}&type=A'
resp = requests.get(forward_url)
forward_data = resp.json()
print(forward_data['Answer'])

# Reverse DNS lookup example
ip = '1.1.1.1'
print(ip)
rev_ip = reverse_ip_to_ptr(ip)
reverse_url = f'https://dns.google/resolve?name={rev_ip}&type=PTR'
resp = requests.get(reverse_url)
reverse_data = resp.json()
print(reverse_data['Answer'])