Common Python String Operations: Concatenation, Splitting, Searching, Replacement, and More

1. String Concatenation Scenario: Build a complete URL for a request.

base_url = "https://api.example.com"
endpoint = "/data"
full_url = base_url + endpoint
print(full_url)

Output: https://api.example.com/data 2. String Splitting Scenario: Extract a specific field from a JSON response.

json_response = '{"id": 1, "name": "John Doe", "email": "[email protected]"}'
response_dict = eval(json_response)  # convert to dict
email = response_dict['email']
print(email)

Output: [email protected] 3. String Searching Scenario: Verify that a response contains a particular text.

response_text = "Welcome to the API documentation."
assert "documentation" in response_text

Output: No output indicates the assertion passed.

4. String Replacement Scenario: Replace placeholders in request parameters.

template = "https://api.example.com/data?user={user_id}"
user_id = "12345"
url = template.format(user_id=user_id)
print(url)

Output: https://api.example.com/data?user=12345 5. String Case Conversion Scenario: Convert request headers to a uniform uppercase form.

headers = {
    "content-type": "application/json",
    "accept": "application/json"
}
upper_headers = {k.upper(): v.upper() for k, v in headers.items()}
print(upper_headers)

Output:

{'CONTENT-TYPE': 'APPLICATION/JSON', 'ACCEPT': 'APPLICATION/JSON'}

6. Substring Extraction Scenario: Extract the path part from a URL.

url = "https://api.example.com/data/12345"
path = url.split("/")[-1]
print(path)

Output: 12345 7. String Formatting Scenario: Use an f‑string to format a message.

name = "John Doe"
message = f"Welcome, {name}!"
print(message)

Output: Welcome, John Doe! 8. Whitespace Trimming Scenario: Clean extra spaces from request parameters.

param = "  user_id=12345  "
cleaned_param = param.strip()
print(cleaned_param)

Output: user_id=12345 9. Splitting to List Scenario: Convert a query‑string into a list of key‑value pairs.

params = "id=12345&name=John Doe"
param_list = params.split("&")
print(param_list)

Output: ['id=12345', 'name=John Doe'] 10. URL Encoding and Decoding Scenario: Encode request parameters for safe transmission.

import urllib.parse
param = "name=John Doe"
encoded_param = urllib.parse.quote(param)
decoded_param = urllib.parse.unquote(encoded_param)
print(encoded_param)
print(decoded_param)

Output: name%3DJohn+Doe and

name=John Doe