import requests
import json

def post_json_data(url, payload, token=None):
    headers = {'Content-Type': 'application/json'}
    if token:
        headers['Authorization'] = f'Bearer {token}'

    try:
        response = requests.post(url, headers=headers, data=json.dumps(payload))
        response.raise_for_status()  # Raises HTTPError for bad responses (4xx or 5xx)
        return response.json()
    except requests.exceptions.HTTPError as err:
        print(f"HTTP error occurred: {err}")
        print(f"Response body: {err.response.text}")
        raise
    except requests.exceptions.ConnectionError as err:
        print(f"Connection error occurred: {err}")
        raise
    except requests.exceptions.Timeout as err:
        print(f"Request timed out: {err}")
        raise
    except requests.exceptions.RequestException as err:
        print(f"An unexpected error occurred: {err}")
        raise

# Example usage:
# api_url = 'https://api.example.com/items'
# data_to_send = {'name': 'New Item', 'description': 'This is a new item.'}
# auth_token = 'your_access_token_if_needed'
# try:
#     result = post_json_data(api_url, data_to_send, auth_token)
#     print("Item created successfully:", result)
# except Exception as e:
#     print(f"Failed to create item: {e}")