I can get html of a web site using lxml module if authentication is not required. However, when it required, how do I input 'User Name' and 'Password' using python?
It very much depends on the method of authentication used. If it's HTTP Basic Auth, then you should be able to pass those headers along with the request. If it's using a web page-based login, you'll need to automate that request and pass back the cookies or whatever session token is used with the next request.
Related
I started recently working on API's and few API providers are not requesting redirect URL while some others are requesting. I have written an algorithmic strategy for trading using python. When I requested for API to Fyers(stockbroker), the team said me to provide a redirect URL. what is a redirect URL? and how to create it?
I have attached image for reference. In the above image, there is a text box for Redirect URL. Can you please explain what exactly is Redirect URL and how to create one for calling API for authentication if my code is on heroku?
The Redirect URL is required by the oAuth workflow: basically the authorisation server will redirect the user back to the URL registered as "Redirect URL" including an authorization code or a token.
If you register a URL like https://myapp.herokuapp.com you will be redirected to
https://myapp.herokuapp.com?access_code=XXX&app_id=YYY
The Redirect URL needs to be a valid accessible page: if the process is manual you just copy the access_code from the browser and use it accordingly.
If it is an application you need to receive the redirect above (the URL is basically your app), fetch the required information (parameters) and implement your logic.
Default Fyers Redirect URL for Testing
Use the default url from fyers
https://trade.fyers.in/api-login/redirect-uri/index.html
Copy the auth key value
Use it in your python app in the second run
You can also use google collab, to run part of code only (authentication) without restarting the whole project
I have to scrape an internal web page of my organization. If I use Beautiful soap I get
"Unauthorized access"
I don't want to put my username/password in the source code because it will be shared across collegues.
If I open the same web url using Firefox It doesn't not ask me to login, the only problem is when I make the same request using python script.
Is there a way to share the same session used by firefox with a python script?
I think my authentication is with my PC because if I log off deleting all cookies When i re-enter I because logged in automatically. Do you know why with my python script this doesn’t not happen?
When you use the browser to login to your organization, you provide your credentials and the server returns a cookie tied to your organization's domain. This cookie has an expiration and allows to use navigate your organization's site without having to login as long as the cookie is valid.
You can read about cookies here:
https://en.wikipedia.org/wiki/HTTP_cookie
Your website scraper does not need to store your credentials. First delete the cookies then, using your browser's developer tools, you can (look at the network tab):
Figure out if your organization uses a separate auth end point
If it's not evident, then you might ask the IT department
Use the auth endpoint to get a cookie using credentials passed in
See how this cookie is used by the system (look at the HTTP request/response headers)
Use this cookie to scrape the website
Share your code freely - if someone needs to scrape the website then they can either pass in their credentials, or use a curl command to get/set a valid cookie header
1) After authenticating in your Firefox browser, make sure to get the cookie key/value.
2) Use that data in the code below :
from bs4 import BeautifulSoup
import requests
browser_cookies = {'your_cookie_key':'your_cookie_value'}
s = requests.Session()
r = s.get(your_url, cookies=browser_cookies)
bsoup = BeautifulSoup(r.text, 'lxml')
The requests.Session() is for persistence.
One more tips, you could also call your script like that :
python3 /path/to/script/script.py cookies_key cookies_value
Then, get the two values with sys module. The code will be :
import sys
browser_cookies = {sys.argv[1]:sys.argv[2]}
I am working on scraping databases that I have access to using the duke library web proxy. I encountered the issue that since the data base is accessed through a proxy server, I can't directly scrape this database as I would if the database was did not require proxy authentication.
I tried several thing:
I wrote one script that logs into the duke network (https://shib.oit.duke.edu/idp/AuthnEngine').
I then hardcode in my login data:
login_data = urllib.urlencode({'j_username' : 'userxx',
'j_password' : 'passwordxx',
'Submit' : 'Enter'
})
I then login:
resp = opener.open('https://shib.oit.duke.edu/idp/AuthnEngine', login_data)
and then I create a cookie jar object to hold the cookies from proxy website.
then i try to access the database with my script and it is still telling me authentication is required. I wanted to know how I can get around the authentication required for the proxy server.
If you have any suggestions please let me know.
Thank you,
Jan
A proxy login does not store cookies but instead uses the Proxy-Authorization header. This header will need to be sent with every request similar to Cookies. The header is of the same format as regular Basic Authentication, although there are different formats possible (Digest, NTLM.) I suggest you check the headers of a normal login and copy and paste the Proxy-Authorization header that was sent.
I am trying to connect to a private page were you have to be logged in to view it using urllib. When I try to connect to the page I just get redirected, to the login page.
Is there a way to log in with urllib or use cookies from my webrowser or something like that?
I have tried to figure out how to do it myself and have failed.
Any help on this would be nice.
If your page uses HTML authentication, use HTTPBasicAuthHandler.
If your page uses authentication by form, use POST request to send login form and store the cookies using cookielib.
Look for Authentication under http://docs.python.org/library/urllib2.html#examples
I am trying to automate files download via a webserver. I plan on using wget or curl or python urllib / urllib2.
Most solutions use wget and urllib and urllib2. They all talk of HHTP based authentication and cookie based authentication. My problem is I dont know which one is used in the website that stores my data.
Here is the interaction with the site:
Normally I login to site http://www.anysite.com/index.cgi?
I get a form with a login and password. I type in both and hit return.
The url stays as http://www.anysite.com/index.cgi? during the entire interaction. But now I have a list of folders and files
If I click on a folder or file the URL changes to http://shamrockstructures.com/cgi-bin/index.cgi?page=download&file=%2Fhome%2Fjanysite%2Fpublic_html%2Fuser_data%2Fuserareas%2Ffile.tar.bz2
And the browser offers me a chance to save the file
I want to know how to figure out whether the site is using HTTP or cookie based authentication. After which I am assuming I can use cookielib or urllib2 in python to connect to it, get the list of files and folders and recursively download everything while staying connected.
p.S: I have tried the cookie cutter ways to connect via wget and wget --http-user "uname" --http-password "passwd" http://www.anysite.com/index.cgi? , but they only return the web form back to me.
If you log in using a Web page, the site is probably using cookie-based authentication. (It could technically use HTTP basic auth, by embedding your credentials in the URI, but this would be a dumb thing to do in most cases.) If you get a separate, smallish dialog with a user name and password field (like this one), it is using HTTP basic authentication.
If you try to log in using HTTP basic auth, and get back the login page, as is happening to you, this is a certain indication that the site is not using HTTP basic auth.
Most sites use cookie-based authentication these days. To do this with an HTTP cilent such as urllib2, you will need to do an HTTP POST of the fields in the login form. (You may need to actually request the login form first, as a site could include a cookie that you need to even log in, but usually this is not necessary.) This should return a "successfully logged in" page that you can test for. Save the cookies you get back from this request. When making the next request, include these cookies. Each request you make may respond with cookies, and you need to save those and send them again with the next request.
urllib2 has a function called a "cookie jar" which will automatically handle the cookies for you as you send requests and receive Web pages. That's what you want.
You can use pycurl like this:
import pycurl
COOKIE_JAR = 'cookiejar' # file to store the cookies
LOGIN_URL = 'http://www.yoursite.com/login.cgi'
USER_FIELD = 'user' # Name of the element in the HTML form
USER = 'joe'
PASSWD_FIELD = 'passwd' # Name of the element in the HTML form
PASSWD = 'MySecretPassword'
def read(html):
"""Read the body of the response, with posible
future html parsing and re-requesting"""
print html
com = pycurl.Curl()
com.setopt(pycurl.WRITEFUNCTION, read)
com.setopt(pycurl.COOKIEJAR, COOKIE_JAR)
com.setopt(pycurl.FOLLOWLOCATION, 1) # follow redirects
com.setopt(pycurl.POST, 1)
com.setopt(pycurl.POSTFIELDS, '%s=%s;%s=%s'%(USER_FIELD, USER,
PASSWD_FIELD, PASSWD))
com.setopt(pycurl.URL, LOGIN_URL )
com.perform()
Plain pycurl it may seam very "primitive" (with the limited setopt approach),
but it gets the job done, and handle pretty well the cookies with the cookie jar option.
AFAIK cookie based authentication is only used once you have logged in successfully atleast ONCE. You can try disabling storing cookies from that domain by changing your browser settings, if you are still able to download files that it should be a HTTP based authentication.
Try doing a equivalent GET request for the (possibly POST) login request that is probably happening right now for login. Use firebug or fiddler to see the login request that is sent.
Also note if there is some javascript code which is returning you a different output, based on your useragent string or some other parameter.
See if httplib, mechanize helps.