I wrote some Python code using requests
to try to build a database of search result links:
from bs4 import BeautifulSoup
import requests
import re
for i in range(0, 1000, 20):
url = "https://www.google.com/search?q=inurl%3Agedt.html&ie=utf-8&start=" + i.__str__() + "0&num=20"
page = requests.get(url)
if i == 0:
soup = BeautifulSoup(page.content)
else:
soup.append(BeautifulSoup(page.content))
links = soup.findAll("a")
clean_links = []
for link in soup.find_all("a",href=re.compile("(?<=/url\?q=)(htt.*://.*)")):
print(re.split(":(?=http)",link["href"].replace("/url?q=","")))
clean_links.append(re.split(":(?=http)", link["href"].replace("/url?q=", "")))
However, after only 40 results Google suspected me of being a robot and quit providing results. That's their prerogative, but is there a (legitimate) way of getting around this?
Can I have some sort of authentication in requests
/ bs4
and, if so, is there some kind of account that lets me pay them for the privilege of scraping all 10-20,000 results?
There are several steps to bypass blocking:
user-agent
to act as a "real" user visit. Because default requests
user-agent
is python-requests
and websites understand that it's most likely a script that sends a request. Check what's your user-agent
. Using the User Agent is more reliable (but up to a certain point).user-agen
t is not enough but you can rotate them to make it a bit more reliable.user-agent
isn't enough. You can pass additional headers . See more HTTP request headers that you can send while making a request.residential proxies
. Residential proxies allow you to choose a specific location (country, city, or mobile carrier) and surf the web as a real user in that area. Proxies can be defined as intermediaries that protect users from general web traffic. They act as buffers while also concealing your IP address.list()
, or save it to .txt
file to save memory and iterate over them while making a request to see what's the results would be, and then move to different types of proxies if the result is not what you were looking for.For more information on how to bypass blocking, you can read the Reducing the chance of being blocked while web scraping blog post.
You can also check the response with status_code
. If a bad request was made (client error 4XX or server error response 5XX), then it can be raised with Response.raise_for_status() . But if the status code for the request is 200 and we call raise_for_status() we get None. This means that there are no errors and everything is fine.
html = requests.get("https://www.google.com/search", params=params, headers=headers, timeout=30)
soup = BeautifulSoup(html.text, "lxml")
if html.status_code == 200:
# the rest of the code
In your code, there's no real point in: for link in soup.find_all("a",href=re.compile("(?<=/url\?q=)(htt.*://.*)")):
as re.compile
could be replaced with proper selector and might improve parsing speed as there's no need to do regex.
Also, you were paginating using the loop variable as the value of the start
URL parameter. I'll show you another way to scrape Google search results with pagination. This method uses the same start
URL parameter which is equal to 0
by default. 0
means the first page, 10
is for the second, and so on. Or you can use SerpApi pagination for Google Search results which is an API.
# https://docs.python-requests.org/en/master/user/quickstart/#passing-parameters-in-urls
params = {
"q": "inurl:gedt.html",
"hl": "en", # language
"gl": "us", # country of the search, US -> USA
"start": 0, # number page by default up to 0
"filter": 0 # shows more pages. By default filter = 1.
}
Also, default search results return several pages. To increase the number of returned pages, you need to set the filter
parameter to 0
and pass it to the URL which will return more pages. Basically, this parameter defines the filters for Similar Results
and Omitted Results
.
You don't have to save the entire page and then look for links by changing the string. You can get links from search results in a simpler way.
links = []
for result in soup.select(".tF2Cxc a"):
links.append(result["href"])
Note: Google periodically changes selectors
While the next button exists, you need to increment the ["start"]
parameter value by 10 to access the next page if
it's present, otherwise we need to break
out of the while
loop:
if soup.select_one('.d6cvqb a[id=pnnext]'):
params["start"] += 10
else:
break
Code and full example in online IDE :
from bs4 import BeautifulSoup
import requests, lxml
# https://docs.python-requests.org/en/master/user/quickstart/#passing-parameters-in-urls
params = {
"q": "inurl:gedt.html",
"hl": "en", # language
"gl": "us", # country of the search, US -> USA
"start": 0, # number page by default up to 0
"filter": 0 # shows more pages. By default filter = 1.
}
# 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/103.0.0.0 Safari/537.36"
}
links = []
while True:
html = requests.get("https://www.google.com/search", params=params, headers=headers, timeout=30)
soup = BeautifulSoup(html.text, "lxml")
if html.status_code == 200:
for result in soup.select(".tF2Cxc a"):
links.append(result["href"])
if soup.select_one(".d6cvqb a[id=pnnext]"):
params["start"] += 10
else:
break
for link in links:
print(link)
Output:
https://www.triton.edu/GE_Certificates/EngineeringTechnologyWeldingCertificate/15.0614-Gedt.html
https://www.triton.edu/GE_Certificates/FacilitiesEngineeringTechnologyCertificate/46.0000-Gedt.html
https://www.triton.edu/GE_Certificates/EngineeringTechnologyDesignCertificate/15.1306-Gedt.html
https://www.triton.edu/GE_Certificates/EngineeringTechnologyFabricationCertificate/15.0499-Gedt.html
https://www.triton.edu/GE_Certificates/BusinessManagementCertificate/52.0201-Gedt.html
https://www.triton.edu/GE_Certificates/GeographicInformationSystemsCertificate/11.0202-Gedt.html
https://www.triton.edu/GE_Certificates/AutomotiveBrakeandSuspensionCertificate/47.0604-Gedt.html
https://www.triton.edu/GE_Certificates/EyeCareAssistantCertificate/51.1803-Gedt.html
https://www.triton.edu/GE_Certificates/InfantToddlerCareCertificate/19.0709-Gedt.html
https://www.triton.edu/GE_Certificates/WebTechnologiesCertificate/11.0801-Gedt.html
... other links
Or you can use SerpApi pagination for Google Search results which is an API. Below, I demonstrate a short code snippet about pagination all pages and extracting links.
from serpapi import GoogleSearch
import os
params = {
# https://docs.python.org/3/library/os.html#os.getenv
"api_key": os.getenv("API_KEY"), # your serpapi api key
"engine": "google", # search engine
"q": "inurl:gedt.html", # search query
"location": "Dallas", # your location
# other parameters
}
search = GoogleSearch(params) # where data extraction happens on the SerpApi backend
pages = search.pagination() # JSON -> Python dict
links = []
for page in pages:
for result in page["organic_results"]:
link = result["link"]
links.append(link)
print(link)
The output will be the same.
Disclaimer, I work for SerpApi.
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