How to check if there is internet connection

Question

I Have to check if my computer is connected to internet (so if i open the broswer i can or i cannot visit an url) , for do this task i tried with some codes:

The first is

import socket
def internet_on():
    try:
        print("checking internet connection..")
        socket.setdefaulttimeout(5)
        host = socket.gethostbyname("www.google.com")
        s = socket.create_connection((host, 80), 2)
        s.close()
        print('internet on.')
        return True

    except Exception as e:
        print(e)
        print("internet off.")
        return False
internet_on()

code that i took from this answer Checking internet connection with Python

After i tried with this:

from urllib.request import urlopen
def internet_on():
        try:
            urlopen("https://www.instagram.com/", timeout=5)
            return True
        except Exception as err:
            print(str(err))
            return False
internet_on()

code that i took from this answer Checking network connection

And this

import socket
REMOTE_SERVER = "www.google.com"
def internet_on(hostname):
      try:
            # see if we can resolve the host name -- tells us if there is
            # a DNS listening
            host = socket.gethostbyname(hostname)
            # connect to the host -- tells us if the host is actually
            # reachable
            s = socket.create_connection((host, 80), 2)
            return True
      except Exception:
            return False
internet_on(REMOTE_SERVER)

code that i took from this answer Test if an internet connection is present in python

If the connection is active the codes work fines but when there is no connection all this codes raise the same errors:

Traceback (most recent call last):
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\connection.py", line 159, in _new_conn
    (self._dns_host, self.port), self.timeout, **extra_kw)
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\util\connection.py", line 57, in create_connection
    for res in socket.getaddrinfo(host, port, family, socket.SOCK_STREAM):
  File "C:\Program Files\Python37-32\lib\socket.py", line 748, in getaddrinfo
    for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
socket.gaierror: [Errno 11001] getaddrinfo failed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\connectionpool.py", line 600, in urlopen
    chunked=chunked)
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\connectionpool.py", line 343, in _make_request
    self._validate_conn(conn)
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\connectionpool.py", line 839, in _validate_conn
    conn.connect()
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\connection.py", line 301, in connect
    conn = self._new_conn()
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\connection.py", line 168, in _new_conn
    self, "Failed to establish a new connection: %s" % e)
urllib3.exceptions.NewConnectionError: <urllib3.connection.VerifiedHTTPSConnection object at 0x03B39E90>: Failed to establish a new connection: [Errno 11001] getaddrinfo failed

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\requests\adapters.py", line 449, in send
    timeout=timeout
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\connectionpool.py", line 638, in urlopen
    _stacktrace=sys.exc_info()[2])
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\urllib3\util\retry.py", line 398, in increment
    raise MaxRetryError(_pool, url, error or ResponseError(cause))
urllib3.exceptions.MaxRetryError: HTTPSConnectionPool(host='www.instagram.com', port=443): Max retries exceeded with url: /_exploreurself (Caused by NewConnectionError('<urllib3.connection.VerifiedHTTPSConnection object at 0x03B39E90>: Failed to establish a new connection: [Errno 11001] getaddrinfo failed'))

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:/Users/mcara/OneDrive/Desktop/file InstaBot da editare/v0.4/bot.py", line 835, in <module>
    bot.unfollow_process(RANDOM, sense=UP_DOWN, following_target=0, sleep_time=60)
  File "C:/Users/mcara/OneDrive/Desktop/file InstaBot da editare/v0.4/bot.py", line 651, in unfollow_process
    current_following = self.user_following_num(self._username)
  File "C:/Users/mcara/OneDrive/Desktop/file InstaBot da editare/v0.4/bot.py", line 387, in user_following_num
    r = requests.get(url).text
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\requests\api.py", line 75, in get
    return request('get', url, params=params, **kwargs)
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\requests\api.py", line 60, in request
    return session.request(method=method, url=url, **kwargs)
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\requests\sessions.py", line 533, in request
    resp = self.send(prep, **send_kwargs)
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\requests\sessions.py", line 646, in send
    r = adapter.send(request, **kwargs)
  File "C:\Users\mcara\PycharmProjects\1\venv\lib\site-packages\requests\adapters.py", line 516, in send
    raise ConnectionError(e, request=request)
requests.exceptions.ConnectionError: HTTPSConnectionPool(host='www.instagram.com', port=443): Max retries exceeded with url: /_exploreurself (Caused by NewConnectionError('<urllib3.connection.VerifiedHTTPSConnection object at 0x03B39E90>: Failed to establish a new connection: [Errno 11001] getaddrinfo failed'))

Answer 1

Try this one here IP address 216.58.192.142 is one of Google's IP address. Due to static IP address, this code is not robust and may not work always so, replace this IP address with some other website which you believe respond more faster.

The reason why the code uses a fixed IP address instead of a fully qualified domain name (FQDN) is because a FQDN would require a DNS lookup. When the machine does not have a working internet connection, the DNS lookup itself may block the call to urllib_request.urlopen for more than a second.

import urllib2

def internet_on():
    try:
        urllib2.urlopen('http://216.58.192.142', timeout=1)
        return True
    except urllib2.URLError as err: 
        return False

Answer 2

Try to run a ping to www.google.com with the library 'subprocess', an example of code below. This solution is an indirect one, but sometimes is better to delegate in system commands to do certain jobs like this one.

import subprocess
def my_dir(my_path):
    output=''
    try:
        p = subprocess.Popen('ping '+my_path, stdout = subprocess.PIPE, stderr = subprocess.STDOUT,
        #close_fds = True, #not valid for Windows platforms
        shell = True
        )
        output, err = p.communicate()
        #print(output)

    finally:
        if p is not None:
            try: p.kill()
            except: pass
    return output


print(my_dir('www.google.com'))

Then, you can parse its output to know if you have reached Google's servers or not.