What will be scraped

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How university filtering works

Search engine operators Explanation Search query
Label: label:<keyword> Label is a search keyword label:computer_vision
Double-quotes: "" Specific <university name> search label:computer_vision "Michigan State University"
Pipe operator: | <univ. name> OR <univ. abbrivation name> label:computer_vision "Michigan State University"|"U.Michigan"

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Prerequisites

Basic knowledge scraping with CSS selectors

CSS selectors declare which part of the markup a style applies to, thus allowing you to extract data from matching tags and attributes.

If you haven't scraped with CSS selectors, there's a dedicated blog post of mine about how to use CSS selectors when web-scraping that covers what it is, pros and cons, and why they matter from a web-scraping perspective.

Separate virtual environment

If you're on Linux:

python -m venv env && source env/bin/activate

If you're on Windows and using Git Bash:

python -m venv env && source env/Scripts/activate

If you haven't worked with a virtual environment before, have a look at the dedicated Python virtual environments tutorial using Virtualenv and Poetry blog post of mine to get familiar.

In short, it's a thing that creates an independent set of installed libraries including different Python versions that can coexist with each other at the same system, thus preventing libraries or Python version conflicts.

📌Note: This is not a strict requirement for this blog post.

Install libraries:

pip install requests, parsel, google-search-results

Reduce the chance of being blocked

There's a chance that a request might be blocked. Have a look at how to reduce the chance of being blocked while web-scraping, there are eleven methods to bypass blocks from most websites.

Google Scholar Profiles API

You can achieve the same as in the DIY solution below by using Google Scholar Profiles API from SerpApi.

The difference is that there's no need to create the parser and maintain it, figure out how to bypass blocks from search engines and how to scale it.

Example code to integrate to achieve almost the same as in the parsel example:

from urllib.parse import urlsplit, parse_qsl
from serpapi import GoogleSearch


def serpapi_scrape_all_authors_from_university(label: str, university_name: str):
    params = {
       "api_key": "...",                                   # https://serpapi.com/manage-api-key
        "engine": "google_scholar_profiles",               # profile results search engine
        "mauthors":  f'label:{label} "{university_name}"'  # search query
    }
    search = GoogleSearch(params)

    profile_results_data = []

    profiles_is_present = True
    while profiles_is_present:
        profile_results = search.get_dict()

        for profile in profile_results["profiles"]:
            thumbnail = profile["thumbnail"]
            name = profile["name"]
            link = profile["link"]
            author_id = profile["author_id"]
            affiliations = profile["affiliations"]
            email = profile.get("email")
            cited_by = profile.get("cited_by")
            interests = profile.get("interests")

            profile_results_data.append({
                "thumbnail": thumbnail,
                "name": name,
                "link": link,
                "author_id": author_id,
                "email": email,
                "affiliations": affiliations,
                "cited_by": cited_by,
                "interests": interests
            })

        if "next" in profile_results.get("serpapi_pagination", {}):
            # splits URL in parts as a dict() and update search "params" variable to a new page that will be passed to GoogleSearch()
            search.params_dict.update(dict(parse_qsl(urlsplit(profile_results.get("serpapi_pagination").get("next")).query)))
        else:
            profiles_is_present = False

    return profile_results_data


print(json.dumps(serpapi_scrape_all_authors_from_university(label="biology", university_name="Michigan University"), indent=2))

Import libraries:

from urllib.parse import urlsplit, parse_qsl
from serpapi import GoogleSearch
Code Explanation
urllib to split URL in parts and pass new page data to GoogleSearch()

Define a function with argument annotations:

def serpapi_scrape_all_authors_from_university(label: str, university_name: str):
    # further code

Create search parameters and pass them to the search:

params = {
    "api_key": "...",                                  # https://serpapi.com/manage-api-key
    "engine": "google_scholar_profiles",               # profile results search engine
    "mauthors":  f'label:{label} "{university_name}"'  # search query
}
search = GoogleSearch(params)                          # where data extraction happens

Create a temporary list where all the extracted data will be stored:

profile_results_data = []

Create a while loop:

profiles_is_present = True
while profiles_is_present:
    profile_results = search.get_dict()  # JSON converted to Python dictionary 
    # further code..
Code Explanation
search.get_dict() needs to be in the while loop because after each while iteration search parameters will be updated. If it will be outside while loop, the same search parameters (token ID) will be applying over and over again.

Iterate over profile results:

for profile in profile_results["profiles"]:

    print(f'Currently extracting {profile["name"]} with {profile["author_id"]} ID.')

    thumbnail = profile["thumbnail"]
    name = profile["name"]
    link = profile["link"]
    author_id = profile["author_id"]
    affiliations = profile["affiliations"]
    email = profile.get("email")
    cited_by = profile.get("cited_by")
    interests = profile.get("interests")

Append the extracted data to temporary list:

 profile_results_data.append({
    "thumbnail": thumbnail,
    "name": name,
    "link": link,
    "author_id": author_id,
    "email": email,
    "affiliations": affiliations,
    "cited_by": cited_by,
    "interests": interests
})

Check if next page token is present:

if "next" in profile_results.get("serpapi_pagination", {}):
    # splits URL in parts as a dict() and update search "params" variable to a new page that will be passed to GoogleSearch()
    search.params_dict.update(dict(parse_qsl(urlsplit(profile_results.get("serpapi_pagination").get("next")).query)))
else:
    profiles_is_present = False

return profile_results_data

Print extracted data:

print(json.dumps(serpapi_scrape_all_profiles_from_university(label="Deep_Learning", university_name="Harvard University"), indent=2))

Part of the output:

[
  {
    "thumbnail": "https://scholar.googleusercontent.com/citations?view_op=small_photo&user=EL414mgAAAAJ&citpid=3",
    "name": "Richard McCabe",
    "link": "https://scholar.google.com/citations?hl=en&user=EL414mgAAAAJ",
    "author_id": "EL414mgAAAAJ",
    "email": "Verified email at cmich.edu",
    "affiliations": "Central Michigan University",
    "cited_by": 992,
    "interests": [
      {
        "title": "Biology",
        "serpapi_link": "https://serpapi.com/search.json?engine=google_scholar_profiles&hl=en&mauthors=label%3Abiology",
        "link": "https://scholar.google.com/citations?hl=en&view_op=search_authors&mauthors=label:biology"
      },
      {
        "title": "Physiology",
        "serpapi_link": "https://serpapi.com/search.json?engine=google_scholar_profiles&hl=en&mauthors=label%3Aphysiology",
        "link": "https://scholar.google.com/citations?hl=en&view_op=search_authors&mauthors=label:physiology"
      },
      {
        "title": "Pathophysiology",
        "serpapi_link": "https://serpapi.com/search.json?engine=google_scholar_profiles&hl=en&mauthors=label%3Apathophysiology",
        "link": "https://scholar.google.com/citations?hl=en&view_op=search_authors&mauthors=label:pathophysiology"
      }
    ]
  }, ... other profiles results
]

DIY Code

import requests, re, json
from parsel import Selector

def scrape_all_authors_from_university(label: str, university_name: str):

    params = {
        "view_op": "search_authors",                       # author results
        "mauthors": f'label:{label} "{university_name}"',  # search query
        "hl": "en",                                        # language
        "astart": 0                                        # page number
    }

    headers = {
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.87 Safari/537.36",
    }

    profile_results = []

    profiles_is_present = True
    while profiles_is_present:

        html = requests.get("https://scholar.google.com/citations", params=params, headers=headers, timeout=30)
        select = Selector(html.text)

        print(f"extracting authors at page #{params['astart']}.")

        for profile in select.css(".gs_ai_chpr"):
            name = profile.css(".gs_ai_name a::text").get()
            link = f'https://scholar.google.com{profile.css(".gs_ai_name a::attr(href)").get()}'
            affiliations = profile.css(".gs_ai_aff").xpath('normalize-space()').get()
            email = profile.css(".gs_ai_eml::text").get()
            cited_by = profile.css(".gs_ai_cby::text").get()  # Cited by 17143 -> 17143
            interests = profile.css(".gs_ai_one_int::text").getall()

            profile_results.append({
                "profile_name": name,
                "profile_link": link,
                "profile_affiliations": affiliations,
                "profile_email": email,
                "profile_city_by_count": cited_by,
                "profile_interests": interests
            })

        # if next page token is present -> update next page token and increment 10 to get the next page
        if select.css("button.gs_btnPR::attr(onclick)").get():
            # https://regex101.com/r/e0mq0C/1
            params["after_author"] = re.search(r"after_author\\x3d(.*)\\x26", select.css("button.gs_btnPR::attr(onclick)").get()).group(1)  # -> XB0HAMS9__8J
            params["astart"] += 10
        else:
            profiles_is_present = False

    return profile_results


print(json.dumps(scrape_all_authors_from_university(label="biology", university_name="Michigan University"), indent=2))

Code Explanation

Import libraries:

import requests, re, json
from parsel import Selector
Library Explanation
requests to make a request.
re to match parts of HTML via regular expression.
json to make pretty printing, in this case.
parsel to extract and remove data from HTML and XML documents.

Define a function:

def scrape_all_authors_from_university(label: str, university_name: str):
    # further code
Code Explanation
label: str, university_name: str parameter annotations which tells that label and university_name should be a str

Create search query params, request headers and make a request:

# https://docs.python-requests.org/en/master/user/quickstart/#passing-parameters-in-urls
params = {
    "view_op": "search_authors",                       # author results
    "mauthors": f'label:{label} "{university_name}"',  # search query
    "hl": "en",                                        # language
    "astart": 0                                        # page number
}

# https://docs.python-requests.org/en/master/user/quickstart/#custom-headers
headers = {
    "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.87 Safari/537.36",
}
Code Explanation
User-Agent to pretend that it's a "real" user sends a request, not a bot or a script.

Create temporary list to store extracted data:

profile_results = []

Create a while loop:

profiles_is_present = True
while profiles_is_present:
    # further code..

Make a request and pass URL params and headers:

html = requests.get("https://scholar.google.com/citations", params=params, headers=headers, timeout=30)
select = Selector(html.text)
Code Explanation
timeout=30 to tell requests to stop waiting for response after 30 seconds.
Selector() like BeautifulSoup() object, if you used it before.

Extract the data:

for profile in select.css(".gs_ai_chpr"):
    name = profile.css(".gs_ai_name a::text").get()
    link = f'https://scholar.google.com{profile.css(".gs_ai_name a::attr(href)").get()}'
    affiliations = profile.css(".gs_ai_aff").xpath('normalize-space()').get()
    email = profile.css(".gs_ai_eml::text").get()
    cited_by = profile.css(".gs_ai_cby::text").get()  # Cited by 17143 -> 17143
    interests = profile.css(".gs_ai_one_int::text").getall()
Code Explanation
::text or ::attr(<attribute_name>) parsel pseudo-element to grab the text or attributes out of the element node, and get() will grab the actual data.
xpath('normalize-space()') to grab blank next child nodes.
getall() to return al list of all matches.

Append extracted data as to temporary list as dictionary:

profile_results.append({
    "profile_name": name,
    "profile_link": link,
    "profile_affiliations": affiliations,
    "profile_email": email,
    "profile_city_by_count": cited_by,
    "profile_interests": interests
})

Check if the next page token is present:

# if next page token is present -> update next page token and increment 10 to get the next page
if select.css("button.gs_btnPR::attr(onclick)").get():
    # https://regex101.com/r/e0mq0C/1
    params["after_author"] = re.search(r"after_author\\x3d(.*)\\x26", select.css("button.gs_btnPR::attr(onclick)").get()).group(1)  # -> XB0HAMS9__8J
    params["astart"] += 10
else:
    profiles_is_present = False
Code Explanation
re.search() to search next page token via regular expression.
params["astart"] += 10 to increment query parameter to a next page.

Return and print the data:

return profile_results

print(json.dumps(scrape_all_authors_from_university(label="biology", university_name="Michigan University"), indent=2))

Part of the output:

[
  {
    "profile_name": "Richard McCabe",
    "profile_link": "https://scholar.google.com/citations?hl=en&user=EL414mgAAAAJ",
    "profile_affiliations": "Central Michigan University",
    "profile_email": "Verified email at cmich.edu",
    "profile_city_by_count": "992",
    "profile_interests": [
      "Biology",
      "Physiology",
      "Pathophysiology"
    ]
  }, ... other profiles
]

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