cfsign 0.0.3

A simple library for creating CloudFront signatures

CFSign

A Python library for generating AWS CloudFront signed URLs and cookies. This library provides a simple interface for creating signed URLs and cookies for CloudFront private content.

Installation

Using pip:

pip install cfsign

Using Poetry:

poetry add cfsign

Usage

Basic Configuration

import cfsign

# Configure with your CloudFront key pair
cfsign.configure(
    key_pair_id="YOUR_KEY_PAIR_ID",
    private_key="YOUR_PRIVATE_KEY"
)

Creating Signed URLs/Cookies

from cfsign.signature.cloudfront_signature import CloudfrontSignature

# Create a signature for a specific resource
signature = CloudfrontSignature("https://example.cloudfront.net/private/content.mp4")

# Get signed cookies
cookies = signature.cookie_dict
print(cookies)
"""
Gets you something like:
{
    "CloudFront-Policy": {...},
    "CloudFront-Signature": {...},
    "CloudFront-Key-Pair-Id": {...},
}
"""


# Get query string parameters for signed URLs
query_string = signature.query_string
print(query_string)
# prints - Policy&={...}&Signature={...}&Key-Pair-Id={...}

Example: Using with Requests

import requests

# Using signed cookies
response = requests.get(url, cookies=signature.cookie_dict)

# Using signed URL
signed_url = f"{url}?{signature.query_string}"

# You could also use the built-in signed url if you're not using a wildcard for the resource:
signed_url = signature.signed_url

response = requests.get(signed_url)

Features

• Generate CloudFront signed URLs
• Generate CloudFront signed cookies
• Support for custom policies
• RSA signing with PKCS1v15 padding and SHA1 hashing (AWS CloudFront standard)
• Base64 policy encoding/decoding

Development

Setting up Development Environment

1. Clone the repository
2. Install development dependencies:

uv sync

Running Tests

# Set PYTHONPATH to project root
pytest

VSCode Configuration

To run tests in VSCode, create a .env file in your project root:

PYTHONPATH=.