Check for URL in a String - Python

We are given a string that may contain one or more URLs and our task is to extract them efficiently. This is useful for web scraping, text processing, and data validation.

For Example:

Input: s = "My Profile: https://www.geeksforgeeks.org/404.html/ in the portal of https://www.geeksforgeeks.org/"

Output: ['https://www.geeksforgeeks.org/404.html/', 'https://www.geeksforgeeks.org/']

Ouput is a list containing all the URLs.

Below are the several methods to perform this task:

Using re.findall()

re.findall() function in Python is used to find all occurrences of a pattern in a given string and return them as a list.

URLs: ['https://www.geeksforgeeks.org/404.html/', 'https://www.geeksforgeeks.org/']

Explanation:

• https?://\S+ matches URLs starting with http:// or https://.
• www\.\S+ matches URLs starting with www.
• findall(): returns all matches in a list.

Using the urlparse()

urlparse() function from urllib.parse breaks down a URL into components like scheme, domain, path, and query.

URLs: ['https://www.geeksforgeeks.org/404.html/', 'https://www.geeksforgeeks.org/']

Explanation:

• s.split(): function splits the string to words.
• urlparse(word): function checks each word to see if it has a valid scheme (http/https) and domain.
• URLs are added to url list using append() function.

Using urlextract()

urlextract is a third-party Python library used to easily extract URLs from text without writing complex regular expressions. Use the following pip command to install it:

pip install urlextract

Output

['https://www.geeksforgeeks.org/404.html/', 'https://www.geeksforgeeks.org/']

Explanation:

• URLExtract(): creates an extractor object to scan the string.
• find_urls(): detects all URLs in s and returns them as a list, no manual splitting or validation is needed.

Using startswith()

This approach splits the text into words and checks each word using the built-in startswith() method to see if it begins with "http://" or "https://". Matching words are treated as URLs and collected.

Urls: ['https://www.geeksforgeeks.org/404.html/', 'https://www.geeksforgeeks.org/']

Explanation:

• string.split(): splits the string into words.
• i.startswith("https:") or i.startswith("http:"): Checks whether the word begins with a URL scheme.
• res.append(i): Adds the word to the list if it is a URL.

Using find() method

find() is a built-in method in Python that is used to find a specific element in a collection, so we can use it to identify and extract a URL from a string.

Urls: ['https://www.geeksforgeeks.org/404.html/', 'https://www.geeksforgeeks.org/']

Explanation:

• s.split(): funtion splits the string to words.
• i.find("https:") == 0 or i.find("http:") == 0: Checks if the word starts with "https:" or "http:".

Related Articles:

• Regex Tutorial
• re.findall() in Python
• Python Urllib Module
• Python List append() Method
• Python – String startswith()
• Python String split()
• Python String find() Method