After following this tutorial on finding a css class and copying the text on a website, I tried to implement this into a small text code but sadly it didnt work.
I followed the tutorial exactly on the same website and did get the headline of the webpage, but cant get this process to work for any other class on that, or any other , webpage. Am I missing something? I am a beginner programmer and have never used Request HTML or anything similar before.
Here is an example of the code I'm using, the purpose being to grab the random fact that appears in the "af-description" class when you load the webpage.
from requests_html import HTMLSession
session = HTMLSession()
r = session.get('http://mentalfloss.com/amazingfactgenerator')
r.html.find('.af-description', first=True)
description = r.html.find('.af-description', first=True)
print("Fun Fact:" + description.text)
No matter how hard I try and no matter how I rearrange things or try different code, I cant get it to work. It seems to not be able to find the class or the text the class contains. Please help.
What you are trying to do requires that the HTML source contains an element with such a class. A browser does much more than just download HTML; it also downloads CSS and Javascript code when referenced by the page, and executes any scripts attached to the page, which can trigger further network activity. If the content you are looking for was generated by Javascript, you can see the elements in the browser development tools inspector, but that doesn't make the element accessible to the r.html object!
In the case of the URL you tried to scrape, if you look at the network console you'll see that an AJAX request GET request http://mentalfloss.com/api/facts is made to fill the <div af-details> structures, so if you wanted to scrape that data you could just get it as JSON directly from the API:
r = session.get('http://mentalfloss.com/api/facts')
description = r.json()[0]['fact']
print("Fun Fact:" + fact)
You can make the requests_html session render the page with Javascript too by calling r.html.render().
This then uses a headless browser to render the HTML, execute the JavaScript code embedded in it, fetch the AJAX request and render the additional DOM elements, then reflect the whole page back to HTML for your code to mine. The first time you do this the required libraries for the headless browser infrastructure are downloaded for you:
>>> from requests_html import HTMLSession
>>> session = HTMLSession()
>>> r = session.get('http://mentalfloss.com/amazingfactgenerator')
>>> r.html.render()
[W:pyppeteer.chromium_downloader] start chromium download.
Download may take a few minutes.
# .... a lot more information elided
[W:pyppeteer.chromium_downloader] chromium extracted to: /Users/mj/.pyppeteer/local-chromium/533271
>>> r.html.render()
>>> r.html.find('.af-description', first=True)
<Element 'div' class=('af-description',)>
>>> _.text
'The cubicle did not get its name from its shape, but from the Latin “cubiculum” meaning bed chamber.'
However, this requires your computer to do a lot more work; for this specific example, it's easier to just call the API directly.
The div which include the class 'af-description' is not included on the DOM but on a js script. Its normal to not be able to find it.
If you test your script to find a class from the DOM, like this one 'afg-page row' you should be fine.
Related
I am kinda a newbie in data world. So i tried to use bs4 and requests to scrap data from trending youtube videos. I have tried using soup.findall() method. To see if it works i displayed it. But it gives me an empty list. Can you help me fix it? Click here to see the spesific part of the html code.
from bs4 import BeautifulSoup
import requests
r = requests.get("https://www.youtube.com/feed/explore")
soup = BeautifulSoup(r.content,"lxml")
soup.prettify()
trendings = soup.find_all("ytd-video-renderer",attrs = {"class":"style-scope ytd-expanded-
shelf-contents-renderer"})
print(trending)
This webpage is dynamic and contains scripts to load data. Whenever you make a request using requests.get("https://www.youtube.com/feed/explore"), it loads the initial source code file that only contains information like head, meta, etc, and scripts. In a real-world scenario, you will have to wait until scripts load data from the server. BeautifulSoup does not catch the interactions with DOM via JavaScript. That's why soup.find_all("ytd-video-renderer",attrs = {"class":"style-scope ytd-expanded-shelf-contents-renderer"}) gives you empty list as there is no ytd-video-renderer tag or style-scope ytd-expanded-shelf-contents-renderer class.
For dynamic webpages, I think you should use Selenium (or maybe Scrapy).
For Youtube, you can use it's API as well.
I am trying to extract information from an exchange website (chiliz.net) using Python (requests module) and the following code:
data = requests.get(url,time.sleep(15)).text
I used time.sleep since the website is not directly connecting to the exchange main page, but I am not sure it is necessary.
The things is that, I cannot find anything written under <body style> in the HTML text (which is the data variable in this case). How can I reach the full HTML code and then start to extract the price information from this website?
I know Python, but not familiar with websites/HTML that much. So I would appreciate if you explain the website related info like you are talking to a beginner. Thanks!
There could be a few reasons for this.
The website runs behind a proxy server from what I can tell, so this does interfere with your request loading time. This is why it's not directly connecting to the main page.
It might also be the case that the elements are rendered using javascript AFTER the page has loaded. So, you only get the page and not the javascript rendered parts. You can try to increase your sleep() time but I don't think that will help.
You can also use a library called Selenium. It simply automates browsers and you can use the page_source property to obtain the HTML source code.
Code (taken from here)
from selenium import webdriver
browser = webdriver.Firefox()
browser.get("http://example.com")
html_source = browser.page_source
With selenium, you can also set the XPATH to obtain the data of -' extract the price information from this website'; you can see a tutorial on that here. Alternatively,
once you extract the HTML code, you can also use a parser such as bs4 to extract the required data.
I've tried to get the world population from this website: https://www.worldometers.info/world-population/
but I can only get the html code, not the data of the actual numbers.
I already tried to find children of the object I tried to get data from. I also tried to list the whole object, but nothing seemed to work.
'''just importing stuff '''
import urllib.request
import requests
from bs4 import BeautifulSoup
'''getting html from website to text '''
r = requests.get('https://www.worldometers.info/world-population/')
soup = BeautifulSoup(r.text,'html.parser')
'''here it only finds the one object that's is listed below '''
current_population = soup.find('div',{'class':'maincounter-number'}).find_all('span', recursive=False)
print(current_population)
This is the object the information is stored in:
(span class="rts-counter" rel="current_population">retrieving data... </span>
and in 'inspect-mode' you can see this:
(span class="rts-counter" rel="current_population">(span class="rts-nr-sign"></span>(span class="rts-nr-int rts-nr-10e9">7</span>(span class="rts-nr-thsep">,</span>(span class="rts-nr-int rts-nr-10e6">703</span>(span class="rts-nr-thsep">,</span>(span class="rts-nr-int rts-nr-10e3">227</span><span class="rts-nr-thsep">,</span>(span class="rts-nr-int rts-nr-10e0">630</span></span>
I always only get the first one, but want to get the second one from 'inspect-mode'.
Here is a picture of the inspect-mode.
You are going to need a method that lets javascript run such as selenium as this number is set up via a counter that is generated in this script: https://www.realtimestatistics.net/rts/RTSp.js
from selenium import webdriver
d = webdriver.Chrome()
d.get('https://www.worldometers.info/world-population/')
print(d.find_element_by_css_selector('[rel="current_population"]').text)
You could try writing your own version of that javascript script but I wouldn't recommend it.
I didn't need an explicit wait condition for selenium script but that could be added.
The website you are scraping is a JavaScript web app. The element content you see in inspect mode is the result of running some JavaScript code after the page downloads that populates that element. Prior to the JavaScript running, the element only contains the text "retrieving data...", which is what you see in your Python code. Neither the Python requests library nor BeautifulSoup run JavaScript in downloaded HTML -- they only download and parse the HTML, and that is why your code only sees the initial text.
You have two options:
Inspect the JavaScript code or website calls and figure out what HTTP URL the page is calling to retrieve the value it puts into that element. Have your Python code fetch that URL instead and parse the value from the response for that URL.
Use a full browser engine. This StackOverflow answer provides a solution: Web-scraping JavaScript page with Python
Javascript is rendered on the DOM so Beautiful Soup will not work as you want it to.
You will have to make something that lets javascript run(eg: browser) so you can make your own browser using QT4 or the like. Sentdex had a good tutorial on it here:
https://www.youtube.com/watch?v=FSH77vnOGqU
Otherwise, you could use Selenium:
from selenium import webdriver
import time
drive = webdriver.Firefox()
drive.get('https://www.worldometers.info/world-population/')
time.sleep(5)
html = driver.page_source
I run this program but it is giving me only "[]" instead of giving the web page data.please help
import urllib
import re
import lxml.html
start_link= "http://aepcindia.com/ApparelMarketplaces/detail"
html_string = urllib.urlopen(start_link)
dom = lxml.html.fromstring(html_string.read())
side_bar_link = dom.xpath("//*[#id='show_cont']/div/table/tr[2]/td[2]/text()")
print side_bar_link
file = open("next_page.txt","w")
for link in side_bar_link:
file.write(link)
print link
file.close()
The HTML source you are downloading contains an empty content area: <div id="show_cont"></div>. This div is populated later by a javascript function showData(). When you look at the page in a browser, the javascript is executed before, which is not the case when you just download the HTML source using urllib.
To get the data you want, you can try to mimic the POST request in the showData() function or, preferably, scrape the website using a scriptable headless browser.
Update: While a headless browser would be a much more generally applicable approach, in this case it might be overhead here. You actually will be better off reverse engineering the showData() function. The alax-call in that is all too obvious, delivers a plain HTML table and you can also limit searches :)
http://aepcindia.com/ApparelMarketplaces/ajax_detail/search_type:/search_value:
I am trying to write a Python script that will periodically check a website to see if an item is available. I have used requests.get, lxml.html, and xpath successfully in the past to automate website searches. In the case of this particular URL (http://www.anthropologie.com/anthro/product/4120200892474.jsp?cm_vc=SEARCH_RESULTS#/) and others on the same website, my code was not working.
import requests
from lxml import html
page = requests.get("http://www.anthropologie.com/anthro/product/4120200892474.jsp?cm_vc=SEARCH_RESULTS#/")
tree = html.fromstring(page.text)
html_element = tree.xpath(".//div[#class='product-soldout ng-scope']")
at this point, html_element should be a list of elements (I think in this case only 1), but instead it is empty. I think this is because the website is not loading all at once, so when requests.get() goes out and grabs it, it's only grabbing the first part. So my questions are
1: Am I correct in my assessment of the problem?
and
2: If so, is there a way to make requests.get() wait before returning the html, or perhaps another route entirely to get the whole page.
Thanks
Edit: Thanks to both responses. I used Selenium and got my script working.
You are not correct in your assessment of the problem.
You can check the results and see that there's a </html> right near the end. That means you've got the whole page.
And requests.text always grabs the whole page; if you want to stream it a bit at a time, you have to do so explicitly.
Your problem is that the table doesn't actually exist in the HTML; it's build dynamically by client-side JavaScript. You can see that by actually reading the HTML that's returned. So, unless you run that JavaScript, you don't have the information.
There are a number of general solutions to that. For example:
Use selenium or similar to drive an actual browser to download the page.
Manually work out what the JavaScript code does and do equivalent work in Python.
Run a headless JavaScript interpreter against a DOM that you've built up.
The page uses javascript to load the table which is not loaded when requests gets the html so you are getting all the html just not what is generated using javascript, you could use selenium combined with phantomjs for headless browsing to get the html:
from selenium import webdriver
browser = webdriver.PhantomJS()
browser.get("http://www.anthropologie.eu/anthro/index.jsp#/")
html = browser.page_source
print(html)