Scraping Data from a website which uses Power BI - retrieving data from Power BI on a website

Question

I want to scrape data from this page (and pages similar to it): https://cereals.ahdb.org.uk/market-data-centre/historical-data/feed-ingredients.aspx

This page uses Power BI. Unfortunately, finding a way to scrape Power BI is hard, because everyone wants to scrape using/into Power BI, not from it. The closest answer was this question. Yet unrelated.

Firstly, I used Apache tika, and soon I realized the table data is been loading after loading the page. I need the rendered version of the page.

Therefore, I used Selenium. I wanted to Select All at the begining (sending Ctrl+A key combination), but it doesn't work. Maybe it is restricted by the page events (I also tried to remove all the events using developer tools, yet still Ctrl+A doesn't work.

I also tried to read the HTML contents, but Power BI puts div elements on the screen using position:absolute and distinguishing the location of a div in the table (both row and column) is an effortful activity.

Since Power BI uses JSON, I tried to read data from there. However it is so complicated I couldn't find out the rules. It seems it puts keywords somewhere and uses their indices in the table.

Note: I realized that all of the data is not loaded and even shown at the same time. A div of class scroll-bar-part-bar is responsible to act as a scroll bar, and moving that loads/shows other parts of the data.

The code I used to read data is as follows. As mentioned, the order of the produced data differs from what is rendered on the browser:

from selenium import webdriver
from selenium.webdriver.common.keys import Keys

options = webdriver.ChromeOptions()
options.binary_location = "C:/Program Files (x86)/Google/Chrome/Application/chrome.exe"
driver = webdriver.Chrome(options=options, executable_path="C:/Drivers/chromedriver.exe")

driver.get("https://app.powerbi.com/view?r=eyJrIjoiYjVjM2MyNjItZDE1Mi00OWI1LWE5YWYtODY4M2FhYjU4ZDU1IiwidCI6ImExMmNlNTRiLTNkM2QtNDM0Ni05NWVmLWZmMTNjYTVkZDQ3ZCJ9")
parent = driver.find_element_by_xpath('//*[@id="pvExplorationHost"]/div/div/div/div[2]/div/div[2]/div[2]/visual-container[4]/div/div[3]/visual/div')
children = parent.find_elements_by_xpath('.//*')
values = [child.get_attribute('title') for child in children]

I appreciate solutions for any of the above problems. The most interesting for me though, is the convention of storing Power BI data in JSON format.

Answer 1

Putting the scroll part and the JSON aside, I managed to read the data. The key is to read all of the elements inside the parent (which is done in the question):

parent = driver.find_element_by_xpath('//*[@id="pvExplorationHost"]/div/div/div/div[2]/div/div[2]/div[2]/visual-container[4]/div/div[3]/visual/div')
children = parent.find_elements_by_xpath('.//*')

Then sort them using their location:

x = [child.location['x'] for child in children]
y = [child.location['y'] for child in children]
index = np.lexsort((x,y))

To sort what we have read in different lines, this code may help:

rows = []
row = []
last_line = y[index[0]]
for i in index:
    if last_line != y[i]:
        row.append[children[i].get_attribute('title')]
    else:
        rows.append(row)
        row = list([children[i].get_attribute('title')]
rows.append(row)

Answer 2

A few more details about exactly which data you are trying to scrape would have helped to construct a canonical answer. However, to scrape the data within the Commodity and Basis using Selenium, as the the desired element is within an <iframe> so you have to:

• Induce WebDriverWait for the desired frame_to_be_available_and_switch_to_it().

• Induce WebDriverWait for the desired visibility_of_element_located() for the table.

• Induce WebDriverWait for the desired visibility_of_all_elements_located() for the desired data.

• You can use the following Locator Strategies:

• Code Block:

       from selenium import webdriver
       from selenium.webdriver.common.by import By
       from selenium.webdriver.support.ui import WebDriverWait
       from selenium.webdriver.support import expected_conditions as EC
  
       options = webdriver.ChromeOptions() 
       options.add_argument("start-maximized")
       options.add_experimental_option("excludeSwitches", ["enable-automation"])
       options.add_experimental_option('useAutomationExtension', False)
       driver = webdriver.Chrome(options=options, executable_path=r'C:\Utility\BrowserDrivers\chromedriver.exe')
       driver.get("https://ahdb.org.uk/cereals-oilseeds/feed-ingredient-prices")
       WebDriverWait(driver, 20).until(EC.frame_to_be_available_and_switch_to_it((By.TAG_NAME,"iframe")))
       WebDriverWait(driver, 20).until(EC.visibility_of_element_located((By.CSS_SELECTOR, "div.innerContainer")))
       print("Commodity:")
       print([my_elem.text for my_elem in WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.XPATH, "//div[@class='pivotTableCellWrap cell-interactive tablixAlignLeft ' and starts-with(@title, 'Ex-')]//parent::div//preceding::div[1]")))])
       print("-=-=-=-=-=-")
       print("Basis:")
       print([my_elem.text for my_elem in WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.CSS_SELECTOR, "div.pivotTableCellWrap.cell-interactive.tablixAlignLeft[title^='Ex-']")))])
  

• Console Output:

       Commodity:
       ['Argentine Sunflowermeal 32/33%', 'Maize Gluten Feed', 'Pelleted Wheat Feed', 'Rapemeal (34%)', 'Soyameal (Hi Pro)', 'Soyameal, Brazilian (48%)']
       -=-=-=-=-=-
       Basis:
       ['Ex-Store Liverpool', 'Ex-Store Liverpool', 'Ex-Mill Midlands and Southern Mills', 'Ex-Mill Erith', 'Ex-Store East Coast', 'Ex-Store Liverpool']
  

---

Update (as per bounty explanation)

As per your comment as well as the given link on the bounty explanation, to scrape the data from Page 2 within the table under the heading Scouting Location using Selenium, you can use the following solution. For the sake of demonstration I have created a List of first 20 countries and you can expand as much as you wish:

• Code Block:

    from selenium import webdriver
    from selenium.webdriver.support.ui import WebDriverWait
    from selenium.webdriver.common.by import By
    from selenium.webdriver.support import expected_conditions as EC
  
    options = webdriver.ChromeOptions() 
    options.add_argument("start-maximized")
    options.add_experimental_option("excludeSwitches", ["enable-automation"])
    options.add_experimental_option('useAutomationExtension', False)
    driver = webdriver.Chrome(options=options, executable_path=r'C:\WebDrivers\chromedriver.exe')
    driver.get("https://app.powerbi.com/view?r=eyJrIjoiMzE1ODNmYzQtMWZhYS00NTNjLTg1MDUtOTQ2MGMyNDVkZTY3IiwidCI6IjE2M2FjNDY4LWFiYjgtNDRkMC04MWZkLWQ5ZGIxNWUzYWY5NiIsImMiOjh9")
    WebDriverWait(driver, 20).until(EC.element_to_be_clickable((By.XPATH, "//span[@class='navigation-wrapper navigation-wrapper-big']//i[@title='Next Page']"))).click()
    print("Country:")
    print([my_elem.text for my_elem in WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.XPATH, "//div[@class='bodyCells']//div[@class='pivotTableCellWrap cell-interactive ']")))[:20]])
    driver.quit()
  

• Console Output:

    DevTools listening on ws://127.0.0.1:49438/devtools/browser/1b5a2590-5a90-47fd-93c7-cfcf58a6c241
    Country:
    ['Myanmar', 'Myanmar', 'Mozambique', 'Malawi', 'Malawi', 'Mozambique', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Malawi', 'Myanmar', 'Myanmar', 'Myanmar']
  

• Console Output Snapshot: