Safely Managing and Using API Keys in Python

import os
import requests

class ExternalApiClient:
    def __init__(self):
        # Retrieve API key from environment variable
        self.api_key = os.environ.get("MY_EXTERNAL_API_KEY")
        if not self.api_key:
            raise ValueError("MY_EXTERNAL_API_KEY environment variable not set.")
        self.base_url = "https://api.external.com/v1"

    def get_data(self, endpoint, params=None):
        headers = {
            "Authorization": f"Bearer {self.api_key}", # Or 'x-api-key', depending on API
            "Accept": "application/json"
        }
        url = f"{self.base_url}/{endpoint}"

        try:
            response = requests.get(url, headers=headers, params=params)
            response.raise_for_status() # Raise an exception for HTTP errors
            return response.json()
        except requests.exceptions.RequestException as e:
            print(f"API call failed: {e}")
            return None

    def post_data(self, endpoint, data):
        headers = {
            "Authorization": f"Bearer {self.api_key}",
            "Content-Type": "application/json",
            "Accept": "application/json"
        }
        url = f"{self.base_url}/{endpoint}"

        try:
            response = requests.post(url, headers=headers, json=data)
            response.raise_for_status()
            return response.json()
        except requests.exceptions.RequestException as e:
            print(f"API post failed: {e}")
            return None

if __name__ == "__main__":
    # Example Usage:
    # Before running, set the environment variable:
    # export MY_EXTERNAL_API_KEY="your_actual_secure_api_key_here"

    try:
        client = ExternalApiClient()
        print("API client initialized successfully.")

        # Example GET request
        print("
Fetching some data...")
        data = client.get_data("items", {"limit": 5})
        if data:
            print("Received data:", data)

        # Example POST request
        print("
Sending some data...")
        post_response = client.post_data("items", {"name": "New Item", "value": 123})
        if post_response:
            print("Post response:", post_response)

    except ValueError as e:
        print(f"Error: {e}")
        print("Please ensure MY_EXTERNAL_API_KEY is set in your environment.")
    except Exception as e:
        print(f"An unexpected error occurred: {e}")