Are there any built-in functions for basic authentication with urllib3?

Basic Authentication with urllib3

Short Answer: urllib3 doesn't have a dedicated built-in function for basic authentication, but you can easily implement it using the Authorization header with base64-encoded credentials.

How Basic Authentication Works

Basic authentication sends credentials in the HTTP Authorization header using this format: Authorization: Basic <base64-encoded-username:password>

Implementation Methods

Method 1: Manual Base64 Encoding

import urllib3
from base64 import b64encode

# Create a PoolManager instance
http = urllib3.PoolManager()

# Your credentials
username = 'your_username'
password = 'your_password'

# Encode credentials to base64
credentials = b64encode(f'{username}:{password}'.encode()).decode('utf-8')

# Make authenticated request
response = http.request(
    'GET',
    'https://api.example.com/protected',
    headers={
        'Authorization': f'Basic {credentials}'
    }
)

print(f"Status: {response.status}")
print(f"Data: {response.data.decode('utf-8')}")

Method 2: Using urllib3.util.make_headers

import urllib3
from urllib3.util import make_headers

http = urllib3.PoolManager()

# Create basic auth headers automatically
headers = make_headers(basic_auth='username:password')

response = http.request(
    'GET',
    'https://api.example.com/protected',
    headers=headers
)

print(response.data.decode('utf-8'))

Method 3: Reusable Function

import urllib3
from base64 import b64encode

def create_basic_auth_header(username, password):
    """Create a basic authentication header."""
    credentials = b64encode(f'{username}:{password}'.encode()).decode('utf-8')
    return {'Authorization': f'Basic {credentials}'}

# Usage
http = urllib3.PoolManager()
auth_headers = create_basic_auth_header('myuser', 'mypass')

response = http.request(
    'POST',
    'https://api.example.com/data',
    headers=auth_headers,
    body='{"data": "example"}',
    headers={**auth_headers, 'Content-Type': 'application/json'}
)

Handling Authentication Errors

import urllib3
from urllib3.util import make_headers

http = urllib3.PoolManager()

try:
    headers = make_headers(basic_auth='username:password')
    response = http.request('GET', 'https://api.example.com/protected', headers=headers)

    if response.status == 200:
        print("Authentication successful!")
        print(response.data.decode('utf-8'))
    elif response.status == 401:
        print("Authentication failed: Invalid credentials")
    elif response.status == 403:
        print("Authentication failed: Access forbidden")
    else:
        print(f"Request failed with status: {response.status}")

except urllib3.exceptions.HTTPError as e:
    print(f"HTTP error occurred: {e}")

Security Best Practices

1. Always Use HTTPS

# ❌ Never do this - credentials sent in plain text
response = http.request('GET', 'http://api.example.com/protected', headers=headers)

# ✅ Always use HTTPS for authentication
response = http.request('GET', 'https://api.example.com/protected', headers=headers)

2. Store Credentials Securely

import os
from urllib3.util import make_headers

# ✅ Read credentials from environment variables
username = os.getenv('API_USERNAME')
password = os.getenv('API_PASSWORD')

if not username or not password:
    raise ValueError("Missing authentication credentials")

headers = make_headers(basic_auth=f'{username}:{password}')

3. Handle Sensitive Data Properly

import urllib3
from base64 import b64encode

def secure_basic_auth_request(url, username, password):
    """Make an authenticated request with proper cleanup."""
    try:
        # Create credentials
        credentials = b64encode(f'{username}:{password}'.encode()).decode('utf-8')

        http = urllib3.PoolManager()
        response = http.request(
            'GET',
            url,
            headers={'Authorization': f'Basic {credentials}'}
        )

        return response

    finally:
        # Clear sensitive variables
        credentials = None
        username = None
        password = None

Alternative: Using requests Library

For simpler basic authentication, consider using the requests library:

import requests
from requests.auth import HTTPBasicAuth

# Much simpler with requests
response = requests.get(
    'https://api.example.com/protected',
    auth=HTTPBasicAuth('username', 'password')
)

print(response.text)

Summary

While urllib3 doesn't have a dedicated basic authentication function, you can implement it using:

1. Manual base64 encoding with the Authorization header
2. urllib3.util.make_headers() utility function (recommended)
3. Custom helper functions for reusable authentication logic

Always use HTTPS and handle credentials securely when implementing basic authentication in production applications.