How to retrieve the values of dynamic html content using Python - python

I'm using Python 3 and I'm trying to retrieve data from a website. However, this data is dynamically loaded and the code I have right now doesn't work:
url = eveCentralBaseURL + str(mineral)
print("URL : %s" % url);
response = request.urlopen(url)
data = str(response.read(10000))
data = data.replace("\\n", "\n")
print(data)
Where I'm trying to find a particular value, I'm finding a template instead e.g."{{formatPrice median}}" instead of "4.48".
How can I make it so that I can retrieve the value instead of the placeholder text?
Edit: This is the specific page I'm trying to extract information from. I'm trying to get the "median" value, which uses the template {{formatPrice median}}
Edit 2: I've installed and set up my program to use Selenium and BeautifulSoup.
The code I have now is:
from bs4 import BeautifulSoup
from selenium import webdriver
#...
driver = webdriver.Firefox()
driver.get(url)
html = driver.page_source
soup = BeautifulSoup(html)
print "Finding..."
for tag in soup.find_all('formatPrice median'):
print tag.text
Here is a screenshot of the program as it's executing. Unfortunately, it doesn't seem to be finding anything with "formatPrice median" specified.

Assuming you are trying to get values from a page that is rendered using javascript templates (for instance something like handlebars), then this is what you will get with any of the standard solutions (i.e. beautifulsoup or requests).
This is because the browser uses javascript to alter what it received and create new DOM elements. urllib will do the requesting part like a browser but not the template rendering part. A good description of the issues can be found here. This article discusses three main solutions:
parse the ajax JSON directly
use an offline Javascript interpreter to process the request SpiderMonkey, crowbar
use a browser automation tool splinter
This answer provides a few more suggestions for option 3, such as selenium or watir. I've used selenium for automated web testing and its pretty handy.
EDIT
From your comments it looks like it is a handlebars driven site. I'd recommend selenium and beautiful soup. This answer gives a good code example which may be useful:
from bs4 import BeautifulSoup
from selenium import webdriver
driver = webdriver.Firefox()
driver.get('http://eve-central.com/home/quicklook.html?typeid=34')
html = driver.page_source
soup = BeautifulSoup(html)
# check out the docs for the kinds of things you can do with 'find_all'
# this (untested) snippet should find tags with a specific class ID
# see: http://www.crummy.com/software/BeautifulSoup/bs4/doc/#searching-by-css-class
for tag in soup.find_all("a", class_="my_class"):
print tag.text
Basically selenium gets the rendered HTML from your browser and then you can parse it using BeautifulSoup from the page_source property. Good luck :)

I used selenium + chrome
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
url = "www.sitetotarget.com"
options = Options()
options.add_argument('--headless')
options.add_argument('--disable-gpu')
options.add_argument('--no-sandbox')
options.add_argument('--disable-dev-shm-usage')`

Building off another answer. I had a similar issue. wget and curl do not work well anymore to get the content of a web page. It's particularly broken with dynamic and lazy content. Using Chrome (or Firefox or Chromium version of Edge) allows you to deal with redirects and scripting.
Below will launch an instance of Chrome, increase the timeout to 5 sec, and navigate this browser instance to a url. I ran this from Jupyter.
import time
from tqdm.notebook import trange, tqdm
from PIL import Image, ImageFont, ImageDraw, ImageEnhance
from selenium import webdriver
driver = webdriver.Chrome('/usr/bin/chromedriver')
driver.set_page_load_timeout(5)
time.sleep(1)
driver.set_window_size(2100, 9000)
time.sleep(1)
driver.set_window_size(2100, 9000)
## You can manually adjust the browser, but don't move it after this.
## Do stuff ...
driver.quit()
Example of grabbing dynamic content and screenshots of the anchored (hence the "a" tag) HTML object, another name for hyperlink:
url = 'http://www.example.org' ## Any website
driver.get(url)
pageSource = driver.page_source
print(driver.get_window_size())
locations = []
for element in driver.find_elements_by_tag_name("a"):
location = element.location;
size = element.size;
# Collect coordinates of object: left/right, top/bottom
x1 = location['x'];
y1 = location['y'];
x2 = location['x']+size['width'];
y2 = location['y']+size['height'];
locations.append([element,x1,y1,x2,y2, x2-x1, y2-y1])
locations.sort(key = lambda x: -x[-2] - x[-1])
locations = [ (el,x1,y1,x2,y2, width,height)
for el,x1,y1,x2,y2,width,height in locations
if not (
## First, filter links that are not visible (located offscreen or zero pixels in any dimension)
x2 <= x1 or y2 <= y1 or x2<0 or y2<0
## Further restrict if you expect the objects to be around a specific size
## or width<200 or height<100
)
]
for el,x1,y1,x2,y2,width,height in tqdm(locations[:10]):
try:
print('-'*100,f'({width},{height})')
print(el.text[:100])
element_png = el.screenshot_as_png
with open('/tmp/_pageImage.png', 'wb') as f:
f.write(element_png)
img = Image.open('/tmp/_pageImage.png')
display(img)
except Exception as err:
print(err)
Installation for mac+chrome:
pip install selenium
brew cask install chromedriver
brew cask install google-chrome
I was using Mac for the original answer and Ubuntu + Windows 11 preview via WSL2 after updating. Chrome ran from Linux side with X service on Windows to render the UI.
Regarding responsibility, please respect robots.txt on each site.

I know this is an old question, but sometimes there is a better solution than using heavy selenium.
This request module for python comes with JS support (in the background it is still chromium) and you can still use beautifulsoup like normal.
Though, sometimes if you have to click elements or sth, I guess selenium is the only option.

Related

Why is the html content I got from inspector different from what I got from Request?

Here is the site I am trying to scrap data from:
https://www.onestopwineshop.com/collection/type/red-wines
import requests
from bs4 import BeautifulSoup
url = "https://www.onestopwineshop.com/collection/type/red-wines"
response = requests.get(url)
#print(response.text)
soup = BeautifulSoup(response.content,'lxml')
The code I have above.
It seems like the HTML content I got from the inspector is different from what I got from BeautifulSoup.
My guess is that they are preventing me from getting their data as they detected I am not accessing the site with a browser. If so, is there any way to bypass that?
(Update) Attempt with selenium:
from selenium import webdriver
import time
path = "C:\Program Files (x86)\chromedriver.exe"
# start web browser
browser=webdriver.Chrome(path)
#navigate to the page
url = "https://www.onestopwineshop.com/collection/type/red-wines"
browser.get(url)
# sleep the required amount to let the page load
time.sleep(3)
# get source code
html = browser.page_source
# close web browser
browser.close()
Update 2:(loaded with devtool)
Any website with content that is loaded after the inital page load is unavailable with BS4 with your current method. This is because the content will be loaded with an AJAX call via javascript and the requests library is unable to parse and run JS code.
To achieve this you will have to look at something like selenium which controls a browser via python or other languages... There is a seperate version of selenium for each browser i.e firefox, chrome etc.
Personally I use chrome so the drivers can be found here...
https://chromedriver.chromium.org/downloads
download the correct driver for your version of chrome
install selenium via pip
create a scrape.py file and put the driver in the same folder.
then to get the html string to use with bs4
from selenium import webdriver
import time
# start web browser
browser=webdriver.Chrome()
#navigate to the page
browser.get('http://selenium.dev/')
# sleep the required amount to let the page load
time.sleep(2)
# get source code
html = browser.page_source
# close web browser
browser.close()
You should then be able to use the html variable with BS4
I'll actually turn my comment to an answer because it is a solution to your problem :
As other said, this page is loaded dynamically, but there are ways to retrieve data without running javascript, in your case you want to look at the "network" tab or your dev tools and filter "fetch" requests.
This could be particularly interesting for you :
You don't need selenium or beautifulsoup at all, you can just use requests and parse the json, if you are good enough ;)
There is a working cURL requests : curl 'https://api.commerce7.com/v1/product/for-web?&collectionSlug=red-wines' -H 'tenant: one-stop-wine-shop'
You get an error if you don't add the tenant header.
And that's it, no html parsing, no waiting for the page to load, no javascript running. Much more powerful that the selenium solution.

HTML acquired in Python code is not the same as displayed webpage

I have recently started learning web scraping with Scrapy and as a practice, I decided to scrape a weather data table from this url.
By inspecting the table element of the page, I copy its XPath into my code but I only get an empty list when running the code. I tried to check which tables are present in the HTML using this code:
from scrapy import Selector
import requests
import pandas as pd
url = 'https://www.wunderground.com/history/monthly/OIII/date/2000-5'
html = requests.get(url).content
sel = Selector(text=html)
table = sel.xpath('//table')
It only returns one table and it is not the one I wanted.
After some research, I found out that it might have something to do with JavaScript rendering in the page source code and that Python requests can't handle JavaScript.
After going through a number of SO Q&As, I came upon a certain requests-html library which can apparently handle JS execution so I tried acquiring the table using this code snippet:
from requests_html import HTMLSession
from scrapy import Selector
session = HTMLSession()
resp = session.get('https://www.wunderground.com/history/monthly/OIII/date/2000-5')
resp.html.render()
html = resp.html.html
sel = Selector(text=html)
tables = sel.xpath('//table')
print(tables)
But the result doesn't change. How can I acquire that table?
Problem
Multiple problems may be at play here—not only javascript execution, but HTML5 APIs, cookies, user agent, etc.
Solution
Consider using Selenium with headless Chrome or Firefox web driver. Using selenium with a web driver ensures that page will be loaded as intended. Headless mode ensures that you can run your code without spawning the GUI browser—you can, of course, disable headless mode to see what's being done to the page in realtime and even add a breakpoint so that you can debug beyond pdb in the browser's console.
Example Code:
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
chrome_options = Options()
chrome_options.add_argument("--no-sandbox")
chrome_options.add_argument("--headless")
driver = webdriver.Chrome(options=chrome_options)
driver.get("https://www.wunderground.com/history/monthly/OIII/date/2000-5")
tables = driver.find_elements_by_xpath('//table') # There are several APIs to locate elements available.
print(tables)
References
Selenium Github: https://github.com/SeleniumHQ/selenium
Selenium (Python) Documentation: https://selenium-python.readthedocs.io/getting-started.html
Locating Elements: https://selenium-python.readthedocs.io/locating-elements.html
you can use scrapy-splash plugin to work scrapy with Splash (scrapinghub's javascript browser)
Using splash you can render javascript and also execute user events like mouse click

python parse evernote shared notebook

I am trying to get data from evernote 'shared notebook'.
For example, from this one: https://www.evernote.com/pub/missrspink/evernoteexamples#st=p&n=56b67555-158e-4d10-96e2-3b2c57ee372c
I tried to use Beautiful Soup:
url = 'https://www.evernote.com/pub/missrspink/evernoteexamples#st=p&n=56b67555-158e-4d10-96e2-3b2c57ee372c'
r = requests.get(url)
bs = BeautifulSoup(r.text, 'html.parser')
bs
The result doesn't contain any text information from the notebook, only some code.
I also seen an advice to use selenium and find elements by XPath.
For example I want to find the head of this note - 'Term 3 Week2'. In Google Chrome i found that it's XPath is '/html/body/div[1]/div[1]/b/span/u/b'.
So i tried this:
driver = webdriver.PhantomJS()
driver.get(url)
t = driver.find_element_by_xpath('/html/body/div[1]/div[1]/b/span/u/b')
But it also didn't work, the result was 'NoSuchElementException:... '.
I am a newbie in python and especially parsing, so I would be glad to receive any help.
I am using python 3.6.2 and jupiter-notebook.
Thanks in advance.
The easiest way to interface with Evernote is to use their official Python API.
After you've configured your API key and can generally connect, you can then download and reference Notes and Notebooks.
Evernote Notes use their own template language called ENML (EverNote Markup Language) which is a subset of HTML. You'll be able to use BeautifulSoup4 to parse the ENML and extract the elements you're looking for.
If you're trying to extract information against a local installation (instead of their web app) you may also be able to get what you need from the executable. See how to pass arguments to the local install to extract data. For this you're going to need to use the Python3 subprocess module.
HOWEVER
If you want to use selenium, this will get you started:
import selenium.webdriver.support.ui as ui
from selenium.webdriver import Chrome
from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions as EC
# your example URL
URL = 'https://www.evernote.com/pub/missrspink/evernoteexamples#st=p&n=56b67555-158e-4d10-96e2-3b2c57ee372c'
# create the browser interface, and a generic "wait" that we can use
# to intelligently block while the driver looks for elements we expect.
# 10: maximum wait in seconds
# 0.5: polling interval in seconds
driver = Chrome()
wait = ui.WebDriverWait(driver, 10, 0.5)
driver.get(URL)
# Note contents are loaded in an iFrame element
find_iframe = By.CSS_SELECTOR, 'iframe.gwt-Frame'
find_html = By.TAG_NAME, 'html'
# .. so we have to wait for the iframe to exist, switch our driver context
# and then wait for that internal page to load.
wait.until(EC.frame_to_be_available_and_switch_to_it(find_iframe))
wait.until(EC.visibility_of_element_located(find_html))
# since ENML is "just" HTML we can select the top tag and get all the
# contents inside it.
doc = driver.find_element_by_tag_name('html')
print(doc.get_attribute('innerHTML')) # <-- this is what you want
# cleanup our browser instance
driver.quit()

PhantomJS (Selenium) Cannot Load PDFs from direct urls

I was trying to save some PDF from a link via PhantomJS (selenium). So, I refered to this code that turns webpages to pdfs. and it worked just fine when I ran the exactly same code.
So, I have this pdf I wanted to save from a direct url and I tried that script... it didn't work. It just saves a PDF with 1 white page. That's all...
My Code :
from selenium import webdriver
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.common.by import By
def execute(script, args):
driver.execute('executePhantomScript', {'script': script, 'args' : args })
driver = webdriver.PhantomJS('phantomjs')
# hack while the python interface lags
driver.command_executor._commands['executePhantomScript'] = ('POST', '/session/$sessionId/phantom/execute')
driver.get('http://www.planetpublish.com/wp-content/uploads/2011/11/The_Scarlet_Letter_T.pdf')
try:
WebDriverWait(driver, 40).until(EC.presence_of_element_located((By.ID, 'plugin')))
except Exception as TimeoutException:
print("I waited for far too long and still couldn't fine the view.")
pass
# set page format
# inside the execution script, webpage is "this"
pageFormat = '''this.paperSize = {format: "A4", orientation: "portrait" };'''
execute(pageFormat, [])
# render current page
render = '''this.render("test2.pdf")'''
execute(render, [])
I'm not sure what's happening and why is it happening. Need some assistance.
EDIT: This is just the test PDF that I was trying to get via Selenium. There are some other PDFs which I need to get and that website is checking god-knows-what to decide whether it's a human or a bot. So, Selenium is the only way.
EDIT 2 : So, here's the website I was practicing on : http://services.ecourts.gov.in/ecourtindia/cases/case_no.php?state_cd=26&dist_cd=8&appFlag=web
Select "Cr Rev - Criminal Revision" from "Case Type" drop down and input any number in case number and year. Click on "Go".
This will show a little table, click on "view" and it should show a table on full page.
Scroll down to the "orders" table and you should see "Copy of order". That's the pdf I'm trying to get.I have tried requests as well and it did not work.
Currently, PhantomJS and Chrome headless doesn't support download a file. If you are OK with Chrome browser, please see my example below. It finds a elements, and then add an attribute download. Finally, it clicks on the link to download the file to default Downloads folder.
import time
driver = webdriver.Chrome()
driver.get('http://www.planetpublish.com/free-ebooks/93/heart-of-darkness/')
pdfLinks = driver.find_elements_by_css_selector(".entry-content ul > li > a")
for pdfLink in pdfLinks:
script = "arguments[0].setAttribute('download',arguments[1]);"
driver.execute_script(script, pdfLink, pdfLink.text)
time.sleep(1)
pdfLink.click()
time.sleep(3)
driver.quit()
If you're just looking at downloading PDFs which aren't protected behind some javascript or stuff (essentially straightforward stuff), I suggest using the requests library instead.
import requests
url ='http://www.planetpublish.com/wp-content/uploads/2011/11/The_Scarlet_Letter_T.pdf'
r = requests.get(url)
with open('The_Scarlet_Letter_T.pdf', 'wb') as f:
f.write(r.content)
# If large file
with requests.get(url, stream=True) as r:
with open('The_Scarlet_Letter_T.pdf', 'wb') as f:
for chunk in r.iter_content(chunk_size=1024):
if chunk:
f.write(chunk)
I recommend you look at the pdfkit library.
import pdfkit
pdfkit.from_url('http://www.planetpublish.com/wp-content/uploads/2011/11/The_Scarlet_Letter_T.pdf', 'out.pdf')
It makes downloading pdfs very simple with python. You will also need to download this for the library to work.
You could also try the code from this link shown below
#!/usr/bin/env python
from contextlib import closing
from selenium.webdriver import Firefox # pip install selenium
from selenium.webdriver.support.ui import WebDriverWait
# use firefox to get page with javascript generated content
with closing(Firefox()) as browser:
browser.get('http://www.planetpublish.com/wp-content/uploads/2011/11/The_Scarlet_Letter_T.pdf')
button = browser.find_element_by_name('button')
button.click()
# wait for the page to load
WebDriverWait(browser, timeout=10).until(
lambda x: x.find_element_by_id('someId_that_must_be_on_new_page'))
# store it to string variable
page_source = browser.page_source
print(page_source)
which you will need to edit to make work for your pdf.

python selenium - how can I get all visible text on the page (i.e., not the page source) [duplicate]

I've been googling this all day with out finding the answer, so apologies in advance if this is already answered.
I'm trying to get all visible text from a large number of different websites. The reason is that I want to process the text to eventually categorize the websites.
After a couple of days of research, I decided that Selenium was my best chance. I've found a way to grab all the text, with Selenium, unfortunately the same text is being grabbed multiple times:
from selenium import webdriver
import codecs
filen = codecs.open('outoput.txt', encoding='utf-8', mode='w+')
driver = webdriver.Firefox()
driver.get("http://www.examplepage.com")
allelements = driver.find_elements_by_xpath("//*")
ferdigtxt = []
for i in allelements:
if i.text in ferdigtxt:
pass
else:
ferdigtxt.append(i.text)
filen.writelines(i.text)
filen.close()
driver.quit()
The if condition inside the for loop is an attempt at eliminating the problem of fetching the same text multiple times - it does not however, only work as planned on some webpages. (it also makes the script A LOT slower)
I'm guessing the reason for my problem is that - when asking for the inner text of an element - I also get the inner text of the elements nested inside the element in question.
Is there any way around this? Is there some sort of master element I grab the inner text of? Or a completely different way that would enable me to reach my goal? Any help would be greatly appreciated as I'm out of ideas for this one.
Edit: the reason I used Selenium and not Mechanize and Beautiful Soup is because I wanted JavaScript tendered text
Using lxml, you might try something like this:
import contextlib
import selenium.webdriver as webdriver
import lxml.html as LH
import lxml.html.clean as clean
url="http://www.yahoo.com"
ignore_tags=('script','noscript','style')
with contextlib.closing(webdriver.Firefox()) as browser:
browser.get(url) # Load page
content=browser.page_source
cleaner=clean.Cleaner()
content=cleaner.clean_html(content)
with open('/tmp/source.html','w') as f:
f.write(content.encode('utf-8'))
doc=LH.fromstring(content)
with open('/tmp/result.txt','w') as f:
for elt in doc.iterdescendants():
if elt.tag in ignore_tags: continue
text=elt.text or ''
tail=elt.tail or ''
words=' '.join((text,tail)).strip()
if words:
words=words.encode('utf-8')
f.write(words+'\n')
This seems to get almost all of the text on www.yahoo.com, except for text in images and some text that changes with time (done with javascript and refresh perhaps).
Here's a variation on #unutbu's answer:
#!/usr/bin/env python
import sys
from contextlib import closing
import lxml.html as html # pip install 'lxml>=2.3.1'
from lxml.html.clean import Cleaner
from selenium.webdriver import Firefox # pip install selenium
from werkzeug.contrib.cache import FileSystemCache # pip install werkzeug
cache = FileSystemCache('.cachedir', threshold=100000)
url = sys.argv[1] if len(sys.argv) > 1 else "https://stackoverflow.com/q/7947579"
# get page
page_source = cache.get(url)
if page_source is None:
# use firefox to get page with javascript generated content
with closing(Firefox()) as browser:
browser.get(url)
page_source = browser.page_source
cache.set(url, page_source, timeout=60*60*24*7) # week in seconds
# extract text
root = html.document_fromstring(page_source)
# remove flash, images, <script>,<style>, etc
Cleaner(kill_tags=['noscript'], style=True)(root) # lxml >= 2.3.1
print root.text_content() # extract text
I've separated your task in two:
get page (including elements generated by javascript)
extract text
The code is connected only through the cache. You can fetch pages in one process and extract text in another process or defer to do it later using a different algorithm.

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