htpchk.conf

[test_HEAD]
url: http://example.com/

[test_GET]
url: http://example.com/
method: GET

[test_POST]
url: http://example.com/
method: POST
data: Hello World

[test_notfound]
url: http://example.com/notfound.html
notify_interval: 10


[DEFAULT]
#************************************************
;  DEFAULT values
#************************************************

#Target URL.
#url=http://example.com/

#HTTP method
method: HEAD

#POST data
#data: Hello World

#When HTTP error occuered, repeatedly notified with interval seconds.
notify_interval: 600

#after checking, wait bellow seconds.
wait_seconds: 0

#tcp connection timeout seconds.
tcp_timeout = 10

htpchk.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""#8 Simple HTTP Checker
  Usage:
       htpchk (htpchk.conf is needed at same directory.)
       htpchk URL
       htpchk config-file
"""
__NAME__ = '#8 Simple HTTP Checker'
__VERSION__ = '1.2'
__ABOUT__ = 'http://jinim.jp/archives/2136'
__USER_AGENT__ = 'Mozilla/5.0 (compatible; %s/%s; +%s)' % (__NAME__, __VERSION__, __ABOUT__)
DATETIME_FORMAT = "%Y-%m-%d %H:%M:%S"

import os
import sys
import time
import socket
import urllib2
from urllib2 import URLError, HTTPError
from ssl import SSLError
from socket import timeout as SocketTimeout
import urlparse
import tempfile
from ConfigParser import ConfigParser

#url to filename with sha hash.
try:
    import hashlib
    def _urlhash_filename(url): return hashlib.sha224(url).hexdigest()
except:
    import sha
    def _urlhash_filename(url): return sha.new(url).hexdigest()

opener = urllib2.build_opener()
opener.addheaders = [('User-agent', __USER_AGENT__)]
urllib2.install_opener(opener)


class ParamError(Exception): pass


class HeadRequest(urllib2.Request):
    def get_method(self): return "HEAD"


class Site(object):
    def __init__(self, name, url, notify_interval=60*10, method="HEAD", data=None, wait_seconds=0, tcp_timeout=3):
        """When medhod is POST, data is requred."""
        self.name = name
        self.url = url
        self.method = method
        self.data = data
        self.notify_interval = notify_interval
        self.wait_seconds = wait_seconds
    #minimum timeout is 1sec.
        if tcp_timeout<1: tcp_timeout = 1
        self.tcp_timeout = tcp_timeout
        self.notified = os.path.join(tempfile.gettempdir(), "htpcheck-%s" % _urlhash_filename(self.url))

    def check(self):
        socket.setdefaulttimeout(self.tcp_timeout)
        if self.method=="HEAD":
            u = urllib2.urlopen(HeadRequest(self.url))
        elif self.method=="POST":
            u = urllib2.urlopen(self.url, data=self.data)
        elif self.method=="GET":
            u = urllib2.urlopen(self.url)
        else:
            raise ParamError, "method: %s not supported. Supported methods are (HEAD,GET,POST)." % self.method
        return u.info()

    def recovered(self):
        os.rename(self.notified, os.path.join(os.path.dirname(self.notified), os.path.basename(self.notified) + time.strftime("-recovered.%Y%m%d%H%M%S")))

    def notify(self, err):
        msg = log_message(self, err)
        last_notified = 0
        if os.path.exists(self.notified):
            try:
                last_notified = time.mktime(time.strptime(file(self.notified).readlines()[-1].split("\t")[0], DATETIME_FORMAT))
            except ValueError:
                last_notified = 0
        if time.time() > (last_notified + self.notify_interval):
            sys.stderr.write(msg)
            file(self.notified, 'a').write("%s\tnotified\n" % msg[:-1])
        else:
             sys.stdout.write(log_message(self, "[SUPPRESSED] %s" % err))


def log_message(site, msg=None):
    """if msg is not None, message means error.
    """
    if msg:
        format = '%s\tNG\t%s\t%s\t%s\t%s\n'
        return format % (time.strftime(DATETIME_FORMAT), site.name, site.method, site.url, msg)
    else:
        format = '%s\tOK\t%s\t%s\t%s\n'
        return format % (time.strftime(DATETIME_FORMAT), site.name, site.method, site.url)


def config_parse(conf):
    parser = ConfigParser()
    parser.readfp(open(conf))
    sites = list()
    for section in parser.sections():
        url = parser.get(section, 'url')
        method = parser.get(section, 'method')
        if method=="POST":
            data = parser.get(section, 'data')
        else:
            data = None
        notify_interval = parser.getfloat(section, 'notify_interval')
        wait_seconds = parser.getfloat(section, 'wait_seconds')
        tcp_timeout = parser.getint(section, 'tcp_timeout')
        sites.append(Site(section, url, notify_interval, method, data, wait_seconds, tcp_timeout))
    return sites


def main(sites):
    for site in sites:
        try:
            site.check()
            sys.stdout.write(log_message(site))
            if os.path.exists(site.notified):
                site.recovered()
        except (SocketTimeout, SSLError, URLError, HTTPError), err:
            site.notify(err)
        if site.wait_seconds>0: time.sleep(site.wait_seconds)


if __name__=='__main__':
    if len(sys.argv)>1: config = sys.argv[1]
    else: config = os.path.splitext(__file__)[0]+'.conf'

    if not os.path.exists(config):
        if config.startswith('http://') or config.startswith('https://'):
            name = urlparse.urlparse(config)[1].split(':')[0]
            sites = (Site(name, config), )
        else:
            raise ParamError, "config file %s not found." % config
    else:
        sites = config_parse(config)

    main(sites)