https://github.com/jpiaskowski/pycas2020_web_scraping

(spoiler: not me)

me and my programming books

• Is it worth the trouble?
• Is it ethical?
• Tools available in BeautifulSoup and requests
• What to look for in html code
• Parsing json objects with json
• Rudimentary pandas skills
• <pro-tip> All you need to know about html is how tags work </pro-tip>

(note: I have zero legal training - this is not legal advice!)

• Are you scraping copyrighted material?
• Will your scraping activity compromise individual privacy?
• Are you making a large number of request that may overload or damage a server?
• Is it possible the scraping will expose intellectual property you do not own?
• Are there terms of service governing use of the website and are you following those?
• Will your scraping activities diminish the value of the original data?

Store in Cascade, Idaho

Goal: Extract addresses for all Family Dollar stores in Idaho.

https://locations.familydollar.com/id/

import requests # for making standard html requests
from bs4 import BeautifulSoup # magical tool for parsing html data
import json # for parsing data
from pandas import DataFrame as df # data organization

page = requests.get("https://locations.familydollar.com/id/")
soup = BeautifulSoup(page.text, 'html.parser') 

Beautiful Soup will take html or xml content and transform it into a complex tree of objects. Here are several common types:

• BeautifulSoup - the soup (the parsed content)
  
• Tag - main type of bs4 element you will encounter
  
• NavigableString - string within a tag
  
• Comment - special type of NavigableString

This process can be frustrating.

• Start with one representative example and then scale up
• Viewing the page’s html source code is essential
  • Run at your own risk:

print(soup.prettify())

• It is usually easiest to browse via “View Page Source”:
• What attribute or tag sets your content apart from the rest?

Searching for ‘href’ does not work.

dollar_tree_list = soup.find_all('href')
dollar_tree_list

## []

But searching on a specific class is often successful:

dollar_tree_list = soup.find_all(class_ = 'itemlist')
for i in dollar_tree_list[:2]:
  print(i)

## <div class="itemlist"><a dta-linktrack="City index page - Aberdeen" href="https://locations.familydollar.com/id/aberdeen/">Aberdeen</a></div>
## <div class="itemlist"><a dta-linktrack="City index page - American Falls" href="https://locations.familydollar.com/id/american-falls/">American Falls</a></div>

type(dollar_tree_list)
## <class 'bs4.element.ResultSet'>
len(dollar_tree_list)
## 48

Next, extract contents from this BeautifulSoup “ResultSet”.

example = dollar_tree_list[2] # Arco, ID (single representative example)
example_content = example.contents
print(example_content)

## [<a dta-linktrack="City index page - Arco" href="https://locations.familydollar.com/id/arco/">Arco</a>]

Find out what attributes are present in the contents:

Note: contents usually return a list of exactly one item, so the first step is to index that item.

example_content = example.contents[0]
example_content.attrs

## {'dta-linktrack': 'City index page - Arco', 'href': 'https://locations.familydollar.com/id/arco/'}

Extract the relevant attribute:

example_href = example_content['href']
print(example_href)

## https://locations.familydollar.com/id/arco/

city_hrefs = [] # initialise empty list

for i in dollar_tree_list:
    cont = i.contents[0]
    href = cont['href']
    city_hrefs.append(href)

#  check to be sure all went well
for i in city_hrefs[:2]:
  print(i)

## https://locations.familydollar.com/id/aberdeen/
## https://locations.familydollar.com/id/american-falls/

Result: a list of URL’s of Family Dollar stores in Idaho to scrape

page2 = requests.get(city_hrefs[2]) # representative example
soup2 = BeautifulSoup(page2.text, 'html.parser')

from type="application/ld+json"

arco = soup2.find_all(type="application/ld+json")
print(arco[1])

## <script type="application/ld+json">
##  {
##    "@context":"https://schema.org",
##    "@type":"Schema Business Type",
##    "name": "Family Dollar #9143",
##    "address":{
##      "@type":"PostalAddress",
##      "streetAddress":"157 W Grand Avenue",
##      "addressLocality":"Arco",
##      "addressRegion":"ID",
##      "postalCode":"83213",
##      "addressCountry":"US"
##    },
##    "containedIn":"",  
##    "branchOf": {
##      "name":"Family Dollar",
##      "url": "https://www.familydollar.com/"
##    },
##    "url":"https://locations.familydollar.com/id/arco/29143/",
##    "telephone":"208-881-5738",
##    "image": "//hosted.where2getit.com/familydollarstore/images/storefront.png"
##  }           
##  </script>

(address information is in the second list member)

Extract the contents (from the second list item) and index the first (and only) list item:

arco_contents = arco[1].contents[0]
arco_contents

## '\n\t{\n\t  "@context":"https://schema.org",\n\t  "@type":"Schema Business Type",\n\t  "name": "Family Dollar #9143",\n\t  "address":{\n\t    "@type":"PostalAddress",\n\t    "streetAddress":"157 W Grand Avenue",\n\t    "addressLocality":"Arco",\n\t    "addressRegion":"ID",\n\t    "postalCode":"83213",\n\t    "addressCountry":"US"\n\t  },\n\t  "containedIn":"",  \n\t  "branchOf": {\n\t    "name":"Family Dollar",\n\t    "url": "https://www.familydollar.com/"\n\t  },\n\t  "url":"https://locations.familydollar.com/id/arco/29143/",\n\t  "telephone":"208-881-5738",\n\t  "image": "//hosted.where2getit.com/familydollarstore/images/storefront.png"\n\t}\t\t\t\n\t'

Next, convert to a json object:
(these are way easier to work with)

arco_json =  json.loads(arco_contents)

A json object is a dictionary:

type(arco_json)

## <class 'dict'>

print(arco_json)

## {'@context': 'https://schema.org', '@type': 'Schema Business Type', 'name':
'Family Dollar #9143', 'address': {'@type': 'PostalAddress', 'streetAddress': '157 W
Grand Avenue', 'addressLocality': 'Arco', 'addressRegion': 'ID', 'postalCode':
'83213', 'addressCountry': 'US'}, 'containedIn': '', 'branchOf': {'name': 'Family
Dollar', 'url': 'https://www.familydollar.com/'}, 'url':
'https://locations.familydollar.com/id/arco/29143/', 'telephone': '208-881-5738',
'image': '//hosted.where2getit.com/familydollarstore/images/storefront.png'}

arco_address = arco_json['address']
arco_address

## {'@type': 'PostalAddress', 'streetAddress': '157 W Grand Avenue',
'addressLocality': 'Arco', 'addressRegion': 'ID', 'postalCode':
'83213', 'addressCountry': 'US'}

Iterate over the list store URLs in Idaho:

locs_dict = [] # initialise empty list

for link in city_hrefs:
  locpage = requests.get(link)   # request page info
  locsoup = BeautifulSoup(locpage.text, 'html.parser') 
      # parse the page's content
  locinfo = locsoup.find_all(type="application/ld+json") 
      # extract specific element
  loccont = locinfo[1].contents[0]  
      # get contents from the bs4 element set
  locjson = json.loads(loccont)  # convert to json
  locaddr = locjson['address'] # get address
  locs_dict.append(locaddr) # add address to list

locs_df = df.from_records(locs_dict)
locs_df.drop(['@type', 'addressCountry'], axis = 1, inplace = True)
locs_df.head(n = 5)

##         streetAddress addressLocality addressRegion postalCode
## 0   111 N Main Street        Aberdeen            ID      83210
## 1     253 Harrison St  American Falls            ID      83211
## 2  157 W Grand Avenue            Arco            ID      83213
## 3     177 Main Street          Ashton            ID      83420
## 4     747 N. Main St.        Bellevue            ID      83313

df.to_csv(locs_df, "family_dollar_ID_locations.csv", sep = ",", index = False)

“Inspect Element” provides the code for what is displayed in a browser.

“View Page Source” - provides the code for what requests will obtain

There are plugins modifying the source code - so, it should be accessed after the page has loaded in a browser.

• Requires a webdriver to retrieve the content
• It actually opens a web browser, and this info is collected
• Selenium is powerful - it can interact with loaded content in many ways
• After getting data, continue to use BeautifulSoup as before

url = "https://www.walgreens.com/storelistings/storesbycity.jsp?requestType=locator&state=ID"
driver = webdriver.Firefox(executable_path = 'mypath/geckodriver.exe')
driver.get(url)
soup_ID = BeautifulSoup(driver.page_source, 'html.parser')
store_link_soup = soup_ID.find_all(class_ = 'col-xl-4 col-lg-4 col-md-4') 

https://github.com/jpiaskowski/pycas2020_web_scraping