I am using the urllib library to fetch pages. Typically I have the top-level domain name & I wish to extract some information from EVERY page within that domain. Thus, if I have xyz.com, I'd like my code to fetch the data from xyz.com/about etc. Here's what I am using:
import urllib,re
htmlFile = urllib.urlopen("http://www.xyz.com/"+r"(.*)")
html = htmlFile.read()
...............
This doe not do the trick for me though. Any ideas are appreciated.
Thanks.
-T
I don't know why you would expect domain.com/(.*) to work. You need to have a list of all the pages (dynamic or static) within that domain. Your python program cannot automatically know that. This knowledge you must obtain from elsewhere, either by following links or looking at the sitemap of the website.
As a footnote, scraping is a slightly shady business. Always make sure, no matter what method you employ, that you are not violating any terms and conditions.
You are trying to use a regular expression on the web server. Turns out, web servers don't actually support this kind of format, so it's failing.
To do what you're trying to, you need to implement a spider. A program that will download a page, find all the links within it, and decide which of them to follow. Then, downloads each of those pages, and repeats.
Some things to watch out for - looping, multiple links that end up pointing at the same page, links going outside of the domain, and getting banned from the webserver for spamming it with 1000s of requests.
In addition to #zigdon answer I recommend you to take a look at scrapy framework.
CrawlSpider will help you to implement crawling quite easily.
Scrapy has this functionality built in. No recursively getting links. It asynchronously automatically handles all the heavy lifting for you. Just specify your domain and search terms and how deep you want it to search in the page .ie the whole site.
http://doc.scrapy.org/en/latest/index.html
Related
I'm making a system - mostly in Python with Scrapy - in which I can, basically, find information about a specific product. But the thing is that the request URL is massive huge, I got a clue that I should change some parts of it with variables to reach that specific product in which I would like to search for, but the URL has so many fields that I don't know, for sure, how to make it.
e.g: "https://www.amazon.com.br/s?k=demi+lovato+365+dias+do+ano&adgrpid=86887777368&hvadid=392971063429&hvdev=c&hvlocphy=9047761&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=11390662277799676774&hvtargid=kwd-597187395757&hydadcr=5658_10696978&tag=hydrbrgk-20&ref=pd_sl_21pelgocuh_e%2Frobot.txt"
"demi+lovato+365+dias+do+ano" it's the book title, but I can see a lot of information on URL that I simply can't supply and of course, it changes from title to title. One solution I thought could be possible was to POST on search bar the title in which I was looking for and find it on result page but I don't know if it's the best approach since in fact, this is the first time I'll be working with web scraping.
Someone has some tip for how can I do that. All I could find was how to scrape all products for price comparison, scrape specific information about all these products and things like that but nothing about search for specific products.
Thanks for any contribs, this is very important for me and sorry about anything, I'm not a very present user and I'm not an English native speaker.
Feel free to make me any advice about user behavior, be better is always something I aim to.
You should use rule available in scrapy framework. This will help you to define how to navigate the site and its sub-site. Additionally you can configure other tags like span or div other than anchor tags to look for url of the link. By this way, additional query params in the link will be populated by the scrapy session as it emulate click on the hypelinks. If you skip the additional query params in the URL, there is a high chance that you will be blocked
How does scrapy use rules?
You don't need to follow that long link at all, often the different parameters are associated with your current session or settings/filters and you can keep only what you need.
Here is what I meant:
You can generate same result using these 2 urls:
https://www.amazon.com.br/s?k=demi+lovato+365+dias+do+ano
https://www.amazon.com.br/s?k=demi+lovato+365+dias+do+ano&adgrpid=86887777368&hvadid=392971063429&hvdev=c&hvlocphy=9047761&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=11390662277799676774&hvtargid=kwd-597187395757&hydadcr=5658_10696978&tag=hydrbrgk-20&ref=pd_sl_21pelgocuh_e%2Frobot.txt
If both links are generating same results then that's it, otherwise you will definitely have to play with different parameters, you can't predict website behavior without actually doing the test and having a lot of parameters is an issue then try something like:
from urllib.parse import quote_plus
base_url = "https://www.amazon.com.br"
link = base_url + "/k=%s&adgrpid=%s&hvadid=%s" % ( quote_plus(title), '86887777368', '392971063429' )
I'm trying to scrape a website that provides individual access to court cases in New Jersey county courts. I'm having a lot of trouble figuring out how to start though. I've scraped quite a few websites before but I've usually been able to start by adapting the URL to pass through the search parameters. However, when I access this data the URL does not change so I'm at a bit of a loss.
Additionally, there is a test for me to prove that I am not a Robot (which occasionally turns into a ReCaptcha).
On the website linked above, say, for example, the inputs would be:
Case County==Bergen, Docket Type==Landlord Tenant (LT), Docket Number==000001, and Docket Year==19.
I would then like to be able to extract the Defendant Name or anything from the subsequent page.
Does anyone have any advice on how I should proceed with this?
Thanks in advance
Websites which "require input" can be scraped using Selenium, which evaluates the javascript: your python code then executes the page more as a "user" (click here, type there). It's slow.
Alternatively, if you look at the page details, you may see what happens to input, and simply execute the resulting GET or POST url properly formed (For example, Forms, often, will do a POST with the parameters: Look at the code and figure out what parameters get posted and to what URL, and then in python, execute that POST code -- you'll probably need a cookiejar to maintain session info.
HOWEVER As a website maintainer, my advice to you is to not attempt to scrape this site: it doesn't want to be scraped & repeated attempts only escalate defensive activities on the part of the website owner. You may also be violating usage policy, state and/or federal laws.
Instead, look for an alternative API, or alternative source. (NJ Courts may have an alternative API, designed for computer usage: send them an email!)
I am trying to read review data data from alexaskillstore.com website using BeautifulSoup. For this, I am specifying the target url as https://www.alexaskillstore.com/Business-Leadership-Series/B078LNGS5T, where the string after Business-Leadership-Series/ keeps changing for all the different skills.
I want to know how can I input a regular expression or similar code to my input url so that I am able to read every link that starts with https://www.alexaskillstore.com/Business-Leadership-Series/.
You can't. The web is client-server based, so unless the server is kind enough to map the content for you, you have no way to know which URLs will be responsive and which won't.
You may be able to scrape some index page(s) to find the keys (B078LNGS5T and the like) you need. Once you have them all, actually generating the URLs is a simple matter of string substitution.
What I'm looking for, should give me something like this ->
There are many APIs available that can accomplish your task (more precisely the task you describe on your question, not the image :) ). I personally use diffbot, which I discovered after reading this. Beware though, for this kind of "content" extraction does not always end with success, because of the nature of web pages. Instead, it relies on heuristics and training and thus may not suffice for your specific purposes...
If you're wanting an entire screenshot of the page then something like https://stackoverflow.com/questions/1041371/alexa-api may help you?
Otherwise if you're just wanting to get a few key images from the page..
you could use mechanize to assit you. When you connect to a webpage you can search through all the links on the page using:
for link in br.links():
where br is your browser object.
You can see an example here:
Download all the links(related documents) on a webpage using Python
if you print dir(link) it will show you various properties such as link.text and link.url. furthermore you can import urlparse.urlsplit and use it on the url. You can direct the browser towards the URL and scrape the images as shown in the above example.
You should really use a search engines interpretation of the page and the images in it.
You could use, the python wrapper on the bing API, or the xGoogle library.
Beware the xGoogle library fakes to google as if a browser and may not be endorsed way to consume Google's data.
This one should help: http://palewi.re/posts/2008/04/20/python-recipe-grab-a-page-scrape-a-table-download-a-file/
Learns you how to scrape content and images and store it.
I would like to write a program that will find bus stop times and update my personal webpage accordingly.
If I were to do this manually I would
Visit www.calgarytransit.com
Enter a stop number. ie) 9510
Click the button "next bus"
The results may look like the following:
10:16p Route 154
10:46p Route 154
11:32p Route 154
Once I've grabbed the time and routes then I will update my webpage accordingly.
I have no idea where to start. I know diddly squat about web programming but can write some C and Python. What are some topics/libraries I could look into?
Beautiful Soup is a Python library designed for parsing web pages. Between it and urllib2 (urllib.request in Python 3) you should be able to figure out what you need.
What you're asking about is called "web scraping." I'm sure if you google around you'll find some stuff, but the core notion is that you want to open a connection to the website, slurp in the HTML, parse it and identify the chunks you want.
The Python Wiki has a good lot of stuff on this.
Since you write in C, you may want to check out cURL; in particular, take a look at libcurl. It's great.
You can use the mechanize library that is available for Python http://wwwsearch.sourceforge.net/mechanize/
You can use Perl to help you complete your task.
use strict;
use LWP;
my $browser = LWP::UserAgent->new;
my $responce = $browser->get("http://google.com");
print $responce->content;
Your responce object can tell you if it suceeded as well as returning the content of the page.You can also use this same library to post to a page.
Here is some documentation. http://metacpan.org/pod/LWP::UserAgent
That site doesnt offer an API for you to be able to get the appropriate data that you need. In that case you'll need to parse the actual HTML page returned by, for example, a CURL request .
This is called Web scraping, and it even has its own Wikipedia article where you can find more information.
Also, you might find more details in this SO discussion.
As long as the layout of the web page your trying to 'scrape' doesnt regularly change, you should be able to parse the html with any modern day programming language.