test_nginx_vhosts.py

#!/usr/bin/env python3

'''
Criticality: High
Tests that all webserver services (vhosts) are available and reachable.
'''

from pathlib import Path
import re
import requests
import socket
import sys

if sys.version_info < (3, 6, 0):
    sys.exit(2)

try:
    from requests.packages.urllib3.exceptions import InsecureRequestWarning

    requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
except ImportError:
    requests.packages.urllib3.disable_warnings()

sys.path.append(str(Path(__file__).parents[1].resolve()))

# pylint: disable=wrong-import-position
import utils as u  # noqa: E402

'''
This script checks for all enabled vhosts in Nginx conf that:
* The response status code is 200, 401 or 403.
* The host is resolved as 127.0.0.1.
* The Wowza response is correct on /streaming/ (only for mediaserver vhosts).
'''


def get_configs(path: str) -> list:
    configs_dir = Path(path)
    configs = [c.resolve() for c in configs_dir.glob('*.conf')]

    return configs


def get_vhosts(config: Path) -> list:
    # remove comments and blank lines
    sanitize = re.compile(r'(?:\s*#\s*.*)|(?:^\s*)', re.M)
    # capture server blocks
    servers = re.compile(r'^server\s+{(?:\s*(?!server\s{).)+', re.M)

    with open(str(config)) as config_fo:
        config_content = sanitize.sub(r'', config_fo.read())
        vhosts = servers.findall(config_content)

    return vhosts


def get_hostnames(vhost: str) -> list:
    # extract hostname(s) from server_name values
    server_names = re.compile(r'^\s*server_name\s+(.*);$')

    hostnames = []
    for line in vhost.splitlines():
        if server_names.match(line):
            hostnames.extend(server_names.match(line).group(1).split())

    return hostnames


def get_ports(vhost: str) -> list:
    # extract port(s) from listen values
    listens = re.compile(r'^\s*listen\s+(?:.*:)?(\d+)\s*(ssl)?.*;$')

    ports = []
    for line in vhost.splitlines():
        if listens.match(line):
            ports.append(
                (listens.match(line).group(1), 'https' if listens.match(line).group(2) else 'http')
            )

    return ports


def test_vhost(
    ports_info=None,
    domains=None,
    resolution_ignored=None,
    nginx_file=None,
    wowza_dir=None,
    tested=0,
):
    errors = 0
    warnings = 0
    name = nginx_file.name
    for port, proto in ports_info or [(80, False)]:
        for domain in domains or ['localhost']:
            url = '%s://%s:%s' % (proto, domain, port)
            u.info('- testing url "%s" from %s' % (url, name))
            # test domain IP
            ip_error = None
            ip_warning = None
            try:
                ip = socket.gethostbyname(domain)
            except Exception as e:
                ip_error = '%s not resolved: %s' % (domain, e)
            else:
                if ip != '127.0.0.1' and ip != '127.0.1.1':
                    ip_warning = '%s resolve to %s instead of 127.0.0.1' % (domain, ip)
            if ip_error:
                if resolution_ignored and domain in resolution_ignored:
                    u.info('%s (ignored)' % ip_error)
                    ip_error = None
                else:
                    u.error(ip_error)
            elif ip_warning:
                if resolution_ignored and domain in resolution_ignored:
                    u.info('%s (ignored)' % ip_warning)
                    ip_warning = None
                else:
                    u.warning(ip_warning)
            # test url
            req_error = False
            try:
                req = requests.get(
                    url, verify=False, proxies={'http': '', 'https': ''}, timeout=30
                )
                req_time = int(1000 * req.elapsed.total_seconds())
            except Exception as e:
                code = str(e)
                req_time = 0
            else:
                code = req.status_code
            if (
                domain != 'localhost'
                and code not in (200, 401, 403)
                or domain == 'localhost'
                and code not in (200, 401, 403, 404)
            ):
                u.error('%s status: %s, %s ms' % (domain, code, req_time))
                req_error = True
            else:
                if req_time > 10000:
                    u.warning('%s status: %s, %s ms' % (domain, code, req_time))
                    warnings += 1
                if 'mediaserver' in name and wowza_dir:
                    # test /streaming url
                    try:
                        req = requests.get(
                            url + '/streaming/',
                            verify=False,
                            proxies={'http': '', 'https': ''},
                            timeout=30,
                        )
                        req_time = int(1000 * req.elapsed.total_seconds())
                    except Exception as e:
                        code = str(e)
                        req_time = 0
                    else:
                        code = req.status_code
                    if code != 200:
                        u.error('%s streaming: %s, %s ms' % (domain, code, req_time))
                        req_error = True
                    elif req_time > 10000:
                        u.warning('%s streaming: %s, %s ms' % (domain, code, req_time))
                        warnings += 1
            tested += 1

            if ip_warning:
                warnings += 1

            if ip_error or req_error:
                errors += 1

    return tested, warnings, errors


def main():
    print('Check that nginx vhosts are well configured:')
    # check that Nginx dir exists
    nginx_dir = '/etc/nginx/sites-enabled'
    if not Path(nginx_dir).exists():
        u.info('nginx dir does not exists ("%s"), test skipped.' % nginx_dir)
        exit(2)

    # check that Wowza is installed
    wowza_dir = '/usr/local/WowzaStreamingEngine'
    if not Path(wowza_dir).exists():
        wowza_dir = None

    # get envsetup conf
    conf = u.load_conf()

    # get enabled vhosts
    resolution_ignored = conf.get('TESTER_VHOST_RESOLUTION_IGNORED', '').split(',')
    errors = 0
    warnings = 0
    nginx_confs = get_configs(nginx_dir)
    for nginx_conf in nginx_confs:
        tested = 0
        vhosts = get_vhosts(nginx_conf)
        for vhost in vhosts:
            hostnames = get_hostnames(vhost)
            ports = get_ports(vhost)
            t, w, e = test_vhost(
                ports,
                hostnames,
                resolution_ignored,
                nginx_conf,
                wowza_dir,
                tested,
            )
            tested += t
            warnings += w
            errors += e

    if errors:
        exit(1)
    elif warnings:
        exit(3)
    if not tested:
        u.error('no url found in nginx sites-enabled dir')
        exit(1)


if __name__ == '__main__':
    main()