Restarts wifi if no ping to google. Adapt it to Alfred App workflow for quick run.

reenable_wifi.sh

#!/bin/bash
((count = 4))                            # Maximum number to try.
while [[ $count -ne 0 ]] ; do
    ping -c 1 8.8.8.8                      # Try once.
    # ping -c 1 1.2.3.4
    rc=$?
    if [[ $rc -eq 0 ]] ; then
        ((count = 1))                      # If okay, flag to exit loop.
    fi
    ((count = count - 1))                  # So we don't go forever.
done

if [[ $rc -eq 0 ]] ; then                  # Make final determination.
    echo 'Internet is ok'
else
    networksetup -setairportpower airport off &&  networksetup -setairportpower airport on
    echo 'Wi-Fi was restarted'
fi