Checking if a website is up via Python - python

By using python, how can I check if a website is up? From what I read, I need to check the "HTTP HEAD" and see status code "200 OK", but how to do so ?
Cheers
Related
How do you send a HEAD HTTP request in Python?

You could try to do this with getcode() from urllib
import urllib.request
print(urllib.request.urlopen("https://www.stackoverflow.com").getcode())
200
For Python 2, use
print urllib.urlopen("http://www.stackoverflow.com").getcode()
200

I think the easiest way to do it is by using Requests module.
import requests
def url_ok(url):
r = requests.head(url)
return r.status_code == 200

You can use httplib
import httplib
conn = httplib.HTTPConnection("www.python.org")
conn.request("HEAD", "/")
r1 = conn.getresponse()
print r1.status, r1.reason
prints
200 OK
Of course, only if www.python.org is up.

from urllib.request import Request, urlopen
from urllib.error import URLError, HTTPError
req = Request("http://stackoverflow.com")
try:
response = urlopen(req)
except HTTPError as e:
print('The server couldn\'t fulfill the request.')
print('Error code: ', e.code)
except URLError as e:
print('We failed to reach a server.')
print('Reason: ', e.reason)
else:
print ('Website is working fine')
Works on Python 3

import httplib
import socket
import re
def is_website_online(host):
""" This function checks to see if a host name has a DNS entry by checking
for socket info. If the website gets something in return,
we know it's available to DNS.
"""
try:
socket.gethostbyname(host)
except socket.gaierror:
return False
else:
return True
def is_page_available(host, path="/"):
""" This function retreives the status code of a website by requesting
HEAD data from the host. This means that it only requests the headers.
If the host cannot be reached or something else goes wrong, it returns
False.
"""
try:
conn = httplib.HTTPConnection(host)
conn.request("HEAD", path)
if re.match("^[23]\d\d$", str(conn.getresponse().status)):
return True
except StandardError:
return None

The HTTPConnection object from the httplib module in the standard library will probably do the trick for you. BTW, if you start doing anything advanced with HTTP in Python, be sure to check out httplib2; it's a great library.

If server if down, on python 2.7 x86 windows urllib have no timeout and program go to dead lock. So use urllib2
import urllib2
import socket
def check_url( url, timeout=5 ):
try:
return urllib2.urlopen(url,timeout=timeout).getcode() == 200
except urllib2.URLError as e:
return False
except socket.timeout as e:
print False
print check_url("http://google.fr") #True
print check_url("http://notexist.kc") #False

I use requests for this, then it is easy and clean.
Instead of print function you can define and call new function (notify via email etc.). Try-except block is essential, because if host is unreachable then it will rise a lot of exceptions so you need to catch them all.
import requests
URL = "https://api.github.com"
try:
response = requests.head(URL)
except Exception as e:
print(f"NOT OK: {str(e)}")
else:
if response.status_code == 200:
print("OK")
else:
print(f"NOT OK: HTTP response code {response.status_code}")

You may use requests library to find if website is up i.e. status code as 200
import requests
url = "https://www.google.com"
page = requests.get(url)
print (page.status_code)
>> 200

In my opinion, caisah's answer misses an important part of your question, namely dealing with the server being offline.
Still, using requests is my favorite option, albeit as such:
import requests
try:
requests.get(url)
except requests.exceptions.ConnectionError:
print(f"URL {url} not reachable")

If by up, you simply mean "the server is serving", then you could use cURL, and if you get a response than it's up.
I can't give you specific advice because I'm not a python programmer, however here is a link to pycurl http://pycurl.sourceforge.net/.

Hi this class can do speed and up test for your web page with this class:
from urllib.request import urlopen
from socket import socket
import time
def tcp_test(server_info):
cpos = server_info.find(':')
try:
sock = socket()
sock.connect((server_info[:cpos], int(server_info[cpos+1:])))
sock.close
return True
except Exception as e:
return False
def http_test(server_info):
try:
# TODO : we can use this data after to find sub urls up or down results
startTime = time.time()
data = urlopen(server_info).read()
endTime = time.time()
speed = endTime - startTime
return {'status' : 'up', 'speed' : str(speed)}
except Exception as e:
return {'status' : 'down', 'speed' : str(-1)}
def server_test(test_type, server_info):
if test_type.lower() == 'tcp':
return tcp_test(server_info)
elif test_type.lower() == 'http':
return http_test(server_info)

Requests and httplib2 are great options:
# Using requests.
import requests
request = requests.get(value)
if request.status_code == 200:
return True
return False
# Using httplib2.
import httplib2
try:
http = httplib2.Http()
response = http.request(value, 'HEAD')
if int(response[0]['status']) == 200:
return True
except:
pass
return False
If using Ansible, you can use the fetch_url function:
from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.urls import fetch_url
module = AnsibleModule(
dict(),
supports_check_mode=True)
try:
response, info = fetch_url(module, url)
if info['status'] == 200:
return True
except Exception:
pass
return False

my 2 cents
def getResponseCode(url):
conn = urllib.request.urlopen(url)
return conn.getcode()
if getResponseCode(url) != 200:
print('Wrong URL')
else:
print('Good URL')

Here's my solution using PycURL and validators
import pycurl, validators
def url_exists(url):
"""
Check if the given URL really exists
:param url: str
:return: bool
"""
if validators.url(url):
c = pycurl.Curl()
c.setopt(pycurl.NOBODY, True)
c.setopt(pycurl.FOLLOWLOCATION, False)
c.setopt(pycurl.CONNECTTIMEOUT, 10)
c.setopt(pycurl.TIMEOUT, 10)
c.setopt(pycurl.COOKIEFILE, '')
c.setopt(pycurl.URL, url)
try:
c.perform()
response_code = c.getinfo(pycurl.RESPONSE_CODE)
c.close()
return True if response_code < 400 else False
except pycurl.error as err:
errno, errstr = err
raise OSError('An error occurred: {}'.format(errstr))
else:
raise ValueError('"{}" is not a valid url'.format(url))

Related

Multithreading under url open process

I finished editing a script that check the url is requiring a WWW web basic authentication or not and printing the result for the user as in this script :
#!/usr/bin/python
# Importing libraries
from urllib2 import urlopen, HTTPError
import socket
import urllib2
import threading
import time
# Setting up variables
url = open("oo.txt",'r')
response = None
start = time.time()
# Excuting Coommands
start = time.time()
for line in url:
try:
response = urlopen(line, timeout=1)
except HTTPError as exc:
# A 401 unauthorized will raise an exception
response = exc
except socket.timeout:
print ("{0} | Request timed out !!".format(line))
except urllib2.URLError:
print ("{0} | Access error !!".format(line))
auth = response and response.info().getheader('WWW-Authenticate')
if auth and auth.lower().startswith('basic'):
print "requires basic authentication"
elif socket.timeout or urllib2.URLError:
print "Yay"
else:
print "Not requires basic authentication"
print "Elapsed Time: %s" % (time.time() - start)
I have a little things i need your help with the script to edit it here ..
I want the script to check every 10 urls together and give the result for all the urls in one time inside a text file . I read about the multithreading and the processing but i didn't find a match form my case to simplify the code to me .
also i have a problem in the result when a timeout or a url error appears , the script give the result in 2 lines like that :
http://www.test.test
| Access error !!
I want it in one line , why it shows in tow ??
Any help in this issues ?
Thanks in advance
The package concurrent.futures provides functionality, that makes it very easy to use concurrency in Python. You define a function check_url that should be called for each URL. Then you can use the map function the apply the function to each URL in parallel and iterate over the return values.
#! /usr/bin/env python3
import concurrent.futures
import urllib.error
import urllib.request
import socket
def load_urls(pathname):
with open(pathname, 'r') as f:
return [ line.rstrip('\n') for line in f ]
class BasicAuth(Exception): pass
class CheckBasicAuthHandler(urllib.request.BaseHandler):
def http_error_401(self, req, fp, code, msg, hdrs):
if hdrs.get('WWW-Authenticate', '').lower().startswith('basic'):
raise BasicAuth()
return None
def check_url(url):
try:
opener = urllib.request.build_opener(CheckBasicAuthHandler())
with opener.open(url, timeout=1) as u:
return 'requires no authentication'
except BasicAuth:
return 'requires basic authentication'
except socket.timeout:
return 'request timed out'
except urllib.error.URLError as e:
return 'access error ({!r})'.format(e.reason)
if __name__ == '__main__':
urls = load_urls('/tmp/urls.txt')
with concurrent.futures.ThreadPoolExecutor(max_workers=10) as executor:
for url, result in zip(urls, executor.map(check_url, urls)):
print('{}: {}'.format(url, result))

Use httplib to check if a URL will return a certain page?

Im going through several hundred bit.ly links to see if they have been used to shorten a link. If a link has not, it returns this page.
How can I iterate through a list of links to check which ones do NOT return this page?
I tried using the head method used in this question, however that always returned true, of course.
I looked into the head method, but found out that it never returns any data:
>>> import httplib
>>> conn = httplib.HTTPConnection("www.python.org")
>>> conn.request("HEAD","/index.html")
>>> res = conn.getresponse()
>>> print res.status, res.reason
200 OK
>>> data = res.read()
>>> print len(data)
0
>>> data == ''
True
I'm stumped on this, and any help would be great.
If bit.ly returns 404 http code for non-shorten links:
#!/usr/bin/env python
from httplib import HTTPConnection
from urlparse import urlsplit
urls = ["http://bit.ly/NKEIV8", "http://bit.ly/1niCdh9"]
for url in urls:
host, path = urlsplit(url)[1:3]
conn = HTTPConnection(host)
conn.request("HEAD", path)
r = conn.getresponse()
if r.status != 404:
print("{r.status} {url}".format(**vars()))
Unrelated: to speed up the check, you could use multiple threads:
#!/usr/bin/env python
from httplib import HTTPConnection
from multiprocessing.dummy import Pool # use threads
from urlparse import urlsplit
def getstatus(url):
try:
host, path = urlsplit(url)[1:3]
conn = HTTPConnection(host)
conn.request("HEAD", path)
r = conn.getresponse()
except Exception as e:
return url, None, str(e) # error
else:
return url, r.status, None
p = Pool(20) # use 20 concurrent connections
for url, status, error in p.imap_unordered(getstatus, urls):
if status != 404:
print("{status} {url} {error}".format(**vars()))
So, here is a simple way to do that:
import httplib2
h = httplib2.Http(".cache")
resp, content = h.request("http://www.python.org/", "GET")
print content
Source: https://code.google.com/p/httplib2/wiki/Examples

Python script to see if a web page exists without downloading the whole page?

I'm trying to write a script to test for the existence of a web page, would be nice if it would check without downloading the whole page.
This is my jumping off point, I've seen multiple examples use httplib in the same way, however, every site I check simply returns false.
import httplib
from httplib import HTTP
from urlparse import urlparse
def checkUrl(url):
p = urlparse(url)
h = HTTP(p[1])
h.putrequest('HEAD', p[2])
h.endheaders()
return h.getreply()[0] == httplib.OK
if __name__=="__main__":
print checkUrl("http://www.stackoverflow.com") # True
print checkUrl("http://stackoverflow.com/notarealpage.html") # False
Any ideas?
Edit
Someone suggested this, but their post was deleted.. does urllib2 avoid downloading the whole page?
import urllib2
try:
urllib2.urlopen(some_url)
return True
except urllib2.URLError:
return False
how about this:
import httplib
from urlparse import urlparse
def checkUrl(url):
p = urlparse(url)
conn = httplib.HTTPConnection(p.netloc)
conn.request('HEAD', p.path)
resp = conn.getresponse()
return resp.status < 400
if __name__ == '__main__':
print checkUrl('http://www.stackoverflow.com') # True
print checkUrl('http://stackoverflow.com/notarealpage.html') # False
this will send an HTTP HEAD request and return True if the response status code is < 400.
notice that StackOverflow's root path returns a redirect (301), not a 200 OK.
Using requests, this is as simple as:
import requests
ret = requests.head('http://www.example.com')
print(ret.status_code)
This just loads the website's header. To test if this was successfull, you can check the results status_code. Or use the raise_for_status method which raises an Exception if the connection was not succesfull.
How about this.
import requests
def url_check(url):
#Description
"""Boolean return - check to see if the site exists.
This function takes a url as input and then it requests the site
head - not the full html and then it checks the response to see if
it's less than 400. If it is less than 400 it will return TRUE
else it will return False.
"""
try:
site_ping = requests.head(url)
if site_ping.status_code < 400:
# To view the return status code, type this : **print(site.ping.status_code)**
return True
else:
return False
except Exception:
return False
You can try
import urllib2
try:
urllib2.urlopen(url='https://someURL')
except:
print("page not found")

Get URL when handling urllib2.URLError

This pertains to urllib2 specifically, but custom exception handling more generally. How do I pass additional information to a calling function in another module via a raised exception? I'm assuming I would re-raise using a custom exception class, but I'm not sure of the technical details.
Rather than pollute the sample code with what I've tried and failed, I'll simply present it as a mostly blank slate. My end goal is for the last line in the sample to work.
#mymod.py
import urllib2
def openurl():
req = urllib2.Request("http://duznotexist.com/")
response = urllib2.urlopen(req)
#main.py
import urllib2
import mymod
try:
mymod.openurl()
except urllib2.URLError as e:
#how do I do this?
print "Website (%s) could not be reached due to %s" % (e.url, e.reason)
You can add information to and then re-raise the exception.
#mymod.py
import urllib2
def openurl():
req = urllib2.Request("http://duznotexist.com/")
try:
response = urllib2.urlopen(req)
except urllib2.URLError as e:
# add URL and reason to the exception object
e.url = "http://duznotexist.com/"
e.reason = "URL does not exist"
raise e # re-raise the exception, so the calling function can catch it
#main.py
import urllib2
import mymod
try:
mymod.openurl()
except urllib2.URLError as e:
print "Website (%s) could not be reached due to %s" % (e.url, e.reason)
I don't think re-raising the exception is an appropriate way to solve this problem.
As #Jonathan Vanasco said,
if you're opening a.com , and it 301 redirects to b.com , urlopen will automatically follow that because an HTTPError with a redirect was raised. if b.com causes the URLError , the code above marks a.com as not existing
My solution is to overwrite redirect_request of urllib2.HTTPRedirectHandler
import urllib2
class NewHTTPRedirectHandler(urllib2.HTTPRedirectHandler):
def redirect_request(self, req, fp, code, msg, headers, newurl):
m = req.get_method()
if (code in (301, 302, 303, 307) and m in ("GET", "HEAD")
or code in (301, 302, 303) and m == "POST"):
newurl = newurl.replace(' ', '%20')
newheaders = dict((k,v) for k,v in req.headers.items()
if k.lower() not in ("content-length", "content-type")
)
# reuse the req object
# mind that req will be changed if redirection happends
req.__init__(newurl,
headers=newheaders,
origin_req_host=req.get_origin_req_host(),
unverifiable=True)
return req
else:
raise HTTPError(req.get_full_url(), code, msg, headers, fp)
opener = urllib2.build_opener(NewHTTPRedirectHandler)
urllib2.install_opener(opener)
# mind that req will be changed if redirection happends
#req = urllib2.Request('http://127.0.0.1:5000')
req = urllib2.Request('http://www.google.com/')
try:
response = urllib2.urlopen(req)
except urllib2.URLError as e:
print 'error'
print req.get_full_url()
else:
print 'normal'
print response.geturl()
let's try to redirect the url to an unknown url:
import os
from flask import Flask,redirect
app = Flask(__name__)
#app.route('/')
def hello():
# return 'hello world'
return redirect("http://a.com", code=302)
if __name__ == '__main__':
port = int(os.environ.get('PORT', 5000))
app.run(host='0.0.0.0', port=port)
And the result is:
error
http://a.com/
normal
http://www.google.com/

Proxy Check in python

I have written a script in python that uses cookies and POST/GET. I also included proxy support in my script. However, when one enters a dead proxy, the script crashes. Is there any way to check if a proxy is dead/alive before running the rest of my script?
Furthermore, I noticed that some proxies don't handle cookies/POST headers properly. Is there any way to fix this?
The simplest was is to simply catch the IOError exception from urllib:
try:
urllib.urlopen(
"http://example.com",
proxies={'http':'http://example.com:8080'}
)
except IOError:
print "Connection error! (Check proxy)"
else:
print "All was fine"
Also, from this blog post - "check status proxy address" (with some slight improvements):
for python 2
import urllib2
import socket
def is_bad_proxy(pip):
try:
proxy_handler = urllib2.ProxyHandler({'http': pip})
opener = urllib2.build_opener(proxy_handler)
opener.addheaders = [('User-agent', 'Mozilla/5.0')]
urllib2.install_opener(opener)
req=urllib2.Request('http://www.example.com') # change the URL to test here
sock=urllib2.urlopen(req)
except urllib2.HTTPError, e:
print 'Error code: ', e.code
return e.code
except Exception, detail:
print "ERROR:", detail
return True
return False
def main():
socket.setdefaulttimeout(120)
# two sample proxy IPs
proxyList = ['125.76.226.9:80', '213.55.87.162:6588']
for currentProxy in proxyList:
if is_bad_proxy(currentProxy):
print "Bad Proxy %s" % (currentProxy)
else:
print "%s is working" % (currentProxy)
if __name__ == '__main__':
main()
for python 3
import urllib.request
import socket
import urllib.error
def is_bad_proxy(pip):
try:
proxy_handler = urllib.request.ProxyHandler({'http': pip})
opener = urllib.request.build_opener(proxy_handler)
opener.addheaders = [('User-agent', 'Mozilla/5.0')]
urllib.request.install_opener(opener)
req=urllib.request.Request('http://www.example.com') # change the URL to test here
sock=urllib.request.urlopen(req)
except urllib.error.HTTPError as e:
print('Error code: ', e.code)
return e.code
except Exception as detail:
print("ERROR:", detail)
return True
return False
def main():
socket.setdefaulttimeout(120)
# two sample proxy IPs
proxyList = ['125.76.226.9:80', '25.176.126.9:80']
for currentProxy in proxyList:
if is_bad_proxy(currentProxy):
print("Bad Proxy %s" % (currentProxy))
else:
print("%s is working" % (currentProxy))
if __name__ == '__main__':
main()
Remember this could double the time the script takes, if the proxy is down (as you will have to wait for two connection-timeouts).. Unless you specifically have to know the proxy is at fault, handling the IOError is far cleaner, simpler and quicker..
you can use the Proxy-checker library which is as simple as this
from proxy_checker import ProxyChecker
checker = ProxyChecker()
checker.check_proxy('<ip>:<port>')
output :
{
"country": "United States",
"country_code": "US",
"protocols": [
"socks4",
"socks5"
],
"anonymity": "Elite",
"timeout": 1649
}
with the possibility of generating your own proxies and check them with two lines of code
you can use ip-getter website to get the IP by which you are sending a request, then check if the IP is the same as your proxy IP or some thing else. Here is a script for that matter:
import requests
proxy_ip = "<IP>"
proxy_port = "<PORT>"
proxy_user = "<USERNAME>"
proxy_pass = "<PASSWORD>"
proxies = {
"http": f"http://{proxy_user}:{proxy_pass}#{proxy_ip}:{proxy_port}/",
"https": f"http://{proxy_user}:{proxy_pass}#{proxy_ip}:{proxy_port}/"
}
url = 'https://api.ipify.org'
try:
response = requests.get(url, proxies=proxies)
assert response.text==proxy_ip
except:
print("Proxy does not work")
I think that the better approach is like dbr said, handling the exception.
Another solution that could be better in some cases, is to use an external online proxy checker tool to check if a proxy server is alive and then continue using your script without any modification.
There is one nice package Grab
So, if it ok for you, you can write something like this(simple valid proxy checker-generator):
from grab import Grab, GrabError
def get_valid_proxy(proxy_list): #format of items e.g. '128.2.198.188:3124'
g = Grab()
for proxy in proxy_list:
g.setup(proxy=proxy, proxy_type='http', connect_timeout=5, timeout=5)
try:
g.go('google.com')
except GrabError:
#logging.info("Test error")
pass
else:
yield proxy

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