I would like to extract the market information from the following url and all of its subsequent pages:
https://uk.reuters.com/investing/markets/index/.FTSE?sortBy=&sortDir=&pn=1
I have successfully parsed the data that I want from the first page using some code from the following url:
https://impythonist.wordpress.com/2015/01/06/ultimate-guide-for-scraping-javascript-rendered-web-pages
I have also been able to parse out the url for the next page to feed into a loop in order to grab data from the next page. The problem is it crashes before the next page loads for a reason I don't fully understand.
I have a hunch that the class that I have borrowed from 'impythonist' may be causing the problem. I don't know enough object orientated programming to work out the problem. Here is my code, much of which is borrowed from the the url above:
import sys
from PyQt4.QtGui import *
from PyQt4.QtCore import *
from PyQt4.QtWebKit import *
from lxml import html
import re
from bs4 import BeautifulSoup
class Render(QWebPage):
def __init__(self, url):
self.app = QApplication(sys.argv)
QWebPage.__init__(self)
self.loadFinished.connect(self._loadFinished)
self.mainFrame().load(QUrl(url))
self.app.exec_()
def _loadFinished(self, result):
self.frame = self.mainFrame()
self.app.quit()
base_url='https://uk.reuters.com'
complete_next_page='https://uk.reuters.com/investing/markets/index/.FTSE?sortBy=&sortDir=&pn=1'
#LOOP TO RENDER PAGES AND GRAB DATA
while complete_next_page != '':
print ('NEXT PAGE: ',complete_next_page, '\n')
r = Render(complete_next_page) # USE THE CLASS TO RENDER JAVASCRIPT FROM PAGE
result = r.frame.toHtml() # ERROR IS THROWN HERE ON 2nd PAGE
# PARSE THE HTML
soup = BeautifulSoup(result, 'lxml')
row_data=soup.find('div', attrs={'class':'column1 gridPanel grid8'})
print (len(row_data))
# PARSE ALL ROW DATA
stripe_rows=row_data.findAll('tr', attrs={'class':'stripe'})
non_stripe_rows=row_data.findAll('tr', attrs={'class':''})
print (len(stripe_rows))
print (len(non_stripe_rows))
# PARSE SPECIFIC ROW DATA FROM INDEX COMPONENTS
#non_stripe_rows: from 4 to 18 (inclusive) contain data
#stripe_rows: from 2 to 16 (inclusive) contain data
i=2
while i < len(stripe_rows):
print('CURRENT LINE IS: ',str(i))
print(stripe_rows[i])
print('###############################################')
print(non_stripe_rows[i+2])
print('\n')
i+=1
#GETS LINK TO NEXT PAGE
next_page=str(soup.find('div', attrs={'class':'pageNavigation'}).find('li', attrs={'class':'next'}).find('a')['href']) #GETS LINK TO NEXT PAGE WORKS
complete_next_page=base_url+next_page
I have annotated the bits of code that I have written and understand but I don't really know what's going on in the 'Render' class enough to diagnose the error? Unless its something else?
Here is the error:
result = r.frame.toHtml()
AttributeError: 'Render' object has no attribute 'frame'
I don't need to keep the information in the class once I have parsed it out so I was thinking perhaps it could be cleared or reset somehow and then updated to hold the new url information from page 2:n but I have no idea how to do this?
Alternatively if anyone knows another way to grab this specific data from this page and the following ones then that would be equally helpful?
Many thanks in advance.
How about using selenium and phantomjs instead of PyQt.
You can easily get selenium by executing "pip install selenium".
If you use Mac you can get phantomjs by executing "brew install phantomjs".
If your PC is Windows use choco instead of brew, or Ubuntu use apt-get.
from selenium import webdriver
from bs4 import BeautifulSoup
base_url = "https://uk.reuters.com"
first_page = "/business/markets/index/.FTSE?sortBy=&sortDir=&pn=1"
browser = webdriver.PhantomJS()
# PARSE THE HTML
browser.get(base_url + first_page)
soup = BeautifulSoup(browser.page_source, "lxml")
row_data = soup.find('div', attrs={'class':'column1 gridPanel grid8'})
# PARSE ALL ROW DATA
stripe_rows = row_data.findAll('tr', attrs={'class':'stripe'})
non_stripe_rows = row_data.findAll('tr', attrs={'class':''})
print(len(stripe_rows), len(non_stripe_rows))
# GO TO THE NEXT PAGE
next_button = soup.find("li", attrs={"class":"next"})
while next_button:
next_page = next_button.find("a")["href"]
browser.get(base_url + next_page)
soup = BeautifulSoup(browser.page_source, "lxml")
row_data = soup.find('div', attrs={'class':'column1 gridPanel grid8'})
stripe_rows = row_data.findAll('tr', attrs={'class':'stripe'})
non_stripe_rows = row_data.findAll('tr', attrs={'class':''})
print(len(stripe_rows), len(non_stripe_rows))
next_button = soup.find("li", attrs={"class":"next"})
# DONT FORGET THIS!!
browser.quit()
I know the code above is not efficient (too slow I feel), but I think that it will bring you the results you desire. In addition, if the web page you want to scrape does not use Javascript, even PhantomJS and selenium are unnecessary. You can use the requests module. However, since I wanted to show you the contrast with PyQt, I used PhantomJS and Selenium in this answer.
Related
I am making an application in PyQt5 that involves displaying a PDF using the QWebEngineView and PDF.js by Mozilla.
I am able to display the PDF no problem, but I cannot figure out how to either:
1: set the page on load, or
2: update the page after it is already loaded
I have tried the numerous options from other Stackoverflow posts that involve using self.runJavaScript() to change it, but it always results in either "Cannot set property of undefined" or "Object is NoneType".
Here is my method:
def load_file(self, file, page=0) -> None:
url = QtCore.QUrl().fromLocalFile(os.path.abspath("./pdfjs/web/viewer.html"))
query = QtCore.QUrlQuery()
query.addQueryItem("file", os.path.normpath(os.path.abspath(file)))
url.setQuery(query)
self.pdf_view.load(url)
where self.pdf_view is QWebEngineView.
I would appreciate any help on how to accomplish this.
EDIT: I was able to specify the page on load with the # symbol, but as for changing the page without re-loading the whole thing is still unknown to me.
The PDF.js viewer loads some scripts that create a PDFViewer object with all the necessary properties for programmatically navigating pages. So you just need to run some simple javascript on the main viewer page to get the functionality you need. To make things a little nicer to work with, it's also helpful to provide a way to run the javascript synchronously so that return values can be accessed more easily.
Below is a simple working demo that implements that (only tested on Linux). Hopefully it should be clear how to adapt it to work with your own application:
import sys, os
from PyQt5 import QtCore, QtWidgets, QtWebEngineWidgets
# PDFJS = '/usr/share/pdf.js/web/viewer.html'
PDFJS = './pdfjs/web/viewer.html'
class Window(QtWidgets.QWidget):
def __init__(self):
super().__init__()
self.buttonNext = QtWidgets.QPushButton('Next Page')
self.buttonNext.clicked.connect(lambda: self.changePage(+1))
self.buttonPrev = QtWidgets.QPushButton('Previous Page')
self.buttonPrev.clicked.connect(lambda: self.changePage(-1))
self.viewer = QtWebEngineWidgets.QWebEngineView()
layout = QtWidgets.QGridLayout(self)
layout.addWidget(self.viewer, 0, 0, 1, 2)
layout.addWidget(self.buttonPrev, 1, 0)
layout.addWidget(self.buttonNext, 1, 1)
def loadFile(self, file):
url = QtCore.QUrl.fromLocalFile(os.path.abspath(PDFJS))
query = QtCore.QUrlQuery()
query.addQueryItem('file', os.path.abspath(file))
url.setQuery(query)
self.viewer.load(url)
def execJavaScript(self, script):
result = None
def callback(data):
nonlocal result
result = data
loop.quit()
loop = QtCore.QEventLoop()
QtCore.QTimer.singleShot(
0, lambda: self.viewer.page().runJavaScript(script, callback))
loop.exec()
return result
def changePage(self, delta):
page = self.execJavaScript(
'PDFViewerApplication.pdfViewer.currentPageNumber')
self.setCurrentPage(page + int(delta))
def setCurrentPage(self, page):
count = self.execJavaScript(
'PDFViewerApplication.pdfViewer.pagesCount')
if 1 <= page <= count:
self.execJavaScript(
f'PDFViewerApplication.pdfViewer.currentPageNumber = {page}')
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
window = Window()
if len(sys.argv) > 1:
window.loadFile(sys.argv[1])
window.setGeometry(600, 50, 800, 600)
window.show()
sys.exit(app.exec_())
I am trying to webscrape a website that has multiple javascript rendered pages (https://openlibrary.ecampusontario.ca/catalogue/). I am able to get the content from the first page, but I am not sure how to get my script to click on the buttons on the subsequent pages to get that content. Here is my script.
import time
from bs4 import BeautifulSoup as soup
import requests
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
import json
# The path to where you have your chrome webdriver stored:
webdriver_path = '/Users/rawlins/Downloads/chromedriver'
# Add arguments telling Selenium to not actually open a window
chrome_options = Options()
chrome_options.add_argument('--headless')
chrome_options.add_argument('--window-size=1920x1080')
# Fire up the headless browser
browser = webdriver.Chrome(executable_path = webdriver_path,
chrome_options = chrome_options)
# Load webpage
url = "https://openlibrary.ecampusontario.ca/catalogue/"
browser.get(url)
# to ensure that the page has loaded completely.
time.sleep(3)
data = []
# Parse HTML, close browser
page_soup = soup(browser.page_source, 'lxml')
containers = page_soup.findAll("div", {"class":"result-item tooltip"})
for container in containers:
item = {}
item['type'] = "Textbook"
item['title'] = container.find('h4', {'class' : 'textbook-title'}).text.strip()
item['author'] = container.find('p', {'class' : 'textbook-authors'}).text.strip()
item['link'] = "https://openlibrary.ecampusontario.ca/catalogue/" + container.find('h4', {'class' : 'textbook-title'}).a["href"]
item['source'] = "eCampus Ontario"
item['base_url'] = "https://openlibrary.ecampusontario.ca/catalogue/"
data.append(item) # add the item to the list
with open("js-webscrape-2.json", "w") as writeJSON:
json.dump(data, writeJSON, ensure_ascii=False)
browser.quit()
You do not have to actually click on any button. For example, to search for items with the keyword 'electricity', you navigate to the url
https://openlibrary-repo.ecampusontario.ca/rest/filtered-items?query_field%5B%5D=*&query_op%5B%5D=matches&query_val%5B%5D=(%3Fi)electricity&filters=is_not_withdrawn&offset=0&limit=10000
This will return a json string of items with the first item being:
{"items":[{"uuid":"6af61402-b0ec-40b1-ace2-1aa674c2de9f","name":"Introduction to Electricity, Magnetism, and Circuits","handle":"123456789/579","type":"item","expand":["metadata","parentCollection","parentCollectionList","parentCommunityList","bitstreams","all"],"lastModified":"2019-05-09 15:51:06.91","parentCollection":null,"parentCollectionList":null,"parentCommunityList":null,"bitstreams":null,"withdrawn":"false","archived":"true","link":"/rest/items/6af61402-b0ec-40b1-ace2-1aa674c2de9f","metadata":null}, ...
Now, to get that item, you use its uuid, and navigate to:
https://openlibrary.ecampusontario.ca/catalogue/item/?id=6af61402-b0ec-40b1-ace2-1aa674c2de9f
You can proceed like this for any interaction with that website (this is not always working for all websites, but it is working for your website).
To find out what are the urls that are navigated to when you click such and such button or enter text (what I did for the above urls), you can use fiddler.
I made a little script that can help you (selenium).
what this script does is "while the last page of the catalogue is not selected (in this case, contain 'selected' in it's class), i'll scrape , then click next"
while "selected" not in driver.find_elements_by_css_selector("[id='results-pagecounter-pages'] a")[-1].get_attribute("class"):
#your scraping here
driver.find_element_by_css_selector("[id='next-btn']").click()
There's probably a problem that you'll run into using this method, it doesn't wait for the results to load, but you can figure out what to do from here onwards.
Hope it helps
Below is a bit of code I am puzzled with. I have been successful with web scraping info from other sites but this one I can't get my head around. I believe that I am missing something due to, maybe, JS.
My end code will take the mainurl and theurl (which is a link) and add them together. However I can even seem to be able to display theurl out. When I go through the inspect aspect I can see what I need but in page source it is not there. Am I missing something in my code for the JS?
import requests
from bs4 import BeautifulSoup
import csv
b = open('csv/homedepot.csv', 'w', newline='')
a = csv.writer(b,delimiter=',')
mainurl = "http://www.homedepot.ca" ## Main website
theurl = "https://www.homedepot.ca/en/home/categories/appliances/refrigerators-and-freezers.html" ##Target website
r = requests.get(theurl)
soup = BeautifulSoup(r.content, "lxml")
for link in soup.findAll('a'):
print (link.get('href'))
I need to extract all calendar data from page like
"http://www.dukascopy.com/swiss/english/marketwatch/calendars/eccalendar/". Firstly - to extract all html with inner dom.
Using eclipse and Python 3.3, win7. Searched here answers, and coded smth based on them.
Looks like:
from PySide import QtGui, QtDeclarative
from PySide.QtGui import QApplication, QDesktopServices, QImage, QPainter
from PySide.QtCore import QByteArray, QUrl, QTimer, QEventLoop, QIODevice, QObject
from PySide.QtWebKit import QWebFrame, QWebView, QWebPage, QWebSettings
from PySide.QtNetwork import QNetworkAccessManager, QNetworkProxy, QNetworkRequest, QNetworkReply, QNetworkDiskCache
#!/usr/bin/env python
"""
app = QApplication(sys.argv)
web = QWebView()
web.load(QUrl("http://www.dukascopy.com/swiss/english/marketwatch/calendars/eccalendar/"))
web.show()
sys.exit(app.exec_())
"""
app = QApplication(sys.argv)
w = QWebView()
request = QNetworkRequest(QUrl("http://www.dukascopy.com/swiss/english/marketwatch/calendars/eccalendar/"))
reply = w.page().networkAccessManager().get(request)
print(reply)
byte_array = reply.readAll()
plist = reply.rawHeaderList()
print(plist)
print(byte_array)
When loading page to QWebView() it works fine (commented code), but I couldn't find how to extract all html from QWebView(). So i tried via "request" - decommented code. And nothing prints.
Try with signals:
def print_content():
print web.page().mainFrame().toHtml() # or toPlainText()
# or
# print web.page().currentFrame().toHtml() # or toPlainText()
and
web.page().mainFrame().loadFinished.connect(print_content)
# or web.loadFinished.connect(print_content)
web.load(QUrl("http://www.dukascopy.com/swiss/english/marketwatch/calendars/eccalendar/"))
web.show()
print_content should be called then loadFinished signal arrives
I've written a script to test a process involving data input & several pages, but after writing it I've found the forms & main content to be generated from javascript.
The following is a snippet of the script I wrote, and after that initial link the content is generated by JS (its my first python script so excuse any mistakes);
from selenium import webdriver
from selenium.common.exceptions import NoSuchElementException
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.common.action_chains import ActionChains
import time
browser = webdriver.Firefox()
browser.get('http://127.0.0.1:46727/?ajax=1')
assert "Home" in browser.title
# Find and click the Employer Database link
empDatabaseLink = browser.find_element_by_link_text('Employer Database')
click = ActionChains(browser).click(on_element = empDatabaseLink)
click.perform()
# Content loaded by the above link is generated by the JS
# Find and click the Add Employer button
addEmployerButton = browser.find_element_by_id('Add Employer')
addEmployer = ActionChains(browser).click(on_element = addEmployerButton)
addEmployer.perform()
browser.save_screenshot(r'images\Add_Employer_Form.png')
# Input Employer name
employerName = browser.find_element_by_id('name')
employerName.send_keys("Selenium")
browser.save_screenshot(r'images\Entered_Employer_Name.png')
# Move to next
nextButton = broswer.find_element_by_name('button_next')
moveForward = ActionChains(browser).click(on_element = nextButton)
# Move through various steps
# Then
# Move to Finish
moveForward = ActionChains(browser).click(on_element = nextButton)
How do you access page elements that aren't in the source? I've been looking around & found GetEval but not found anything that I can use :/
Well, to the people of the future, our above conversation appears to have lead to the conclusion that xpath is what mark was looking for. So remember to try xpath, and to use the Selenium IDE and Firebug to locate particularly obstinate page elements.