def check_json_format(server):

    for key in ('server_type', 'server_name', 'tor_status', 'fingerprint'):

        if key not in server:

            raise ValueError('%s key not present!\n' % key)

    if server['server_type'] not in ('Exit', 'Relay', 'Bridge'):

        error_message = ('server_type has not the right content!'

                         ' is: %s must be one of: Exit, Relay or Bridge\n') \

            % server['server_type']

        raise ValueError(error_message)

    if not server['tor_status'] in ('Online', 'Offline'):

        error_message = ('tor_status has not the right content!'

                         ' is: %s must be one of: Online or Offline\n') \

            % server['tor_status']

    if FINGERPRINT_REGEX.match(server['fingerprint']) is None:

        raise ValueError('fingerprint has not the right format!\n')

    if server['server_type'] == 'Bridge':

        for key in ('obfs', 'fteproxy', 'flashproxy', 'meek'):

            check_bridge(key, server)

    if 'ip' in server:

        if IP_REGEX.match(server['ip']) is None:

            raise ValueError('ip is not the right format!\n')

        elif PRIVATE_IP_REGEX.match(server['ip']) is not None:

            raise ValueError('ip is not accepted!\n')

    return True

def update_server(server, ip):

    server['last_updated'] = datetime.utcnow().strftime(DATE_FORMAT)

    server['server_status'] = 'Online'

    server['country'] = gi4.country_name_by_addr(ip)

    if server['server_type'] == 'Bridge':

        if 'ip' in server:

            del server['ip']

    else:

        for key in ('obfs', 'fteproxy', 'flashproxy', 'meek'):

            if key in server:

                del server[key]

        server['ip'] = ip

    try:

        filename = ''.join(['data/', server['server_name'].lower(), '.json'])

        with open(filename, 'w', encoding='utf-8') as fb:

            json.dump(server, fb)

        return server

    except Exception as e:

        return e