Set Up Your Environment
- Ensure that you have the necessary Python environment set up for development. Use virtual environments to manage dependencies and avoid conflicts. Installing the major package manager, `pip`, is essential for smoothly managing libraries and APIs.
- Install the `requests` library, which will be used for handling HTTP requests to the UPS API, by running:
pip install requests
Understand the UPS API Requirements
- Review the official UPS API documentation to understand the request format and required parameters for rate calculations. Pay attention to required headers, endpoint URLs, and any potential authentication needs.
- Identify mandatory fields such as the shipper's address, receiver's address, package details (weight, dimensions), and the service type. Ensure that you have all relevant information ready for the API request.
Authentication and Access
- Use OAuth or a similar protocol for accessing the UPS API securely. This usually involves obtaining an access token that must be included in your API request. Verify the process in the official UPS API documentation.
- Implement logic to handle token retrieval, ensuring your code can seamlessly refresh tokens as needed to prevent unauthorized errors due to expired tokens.
Constructing the API Request
- Create a function to assemble the API request payload. This involves using the required fields identified earlier, structured according to the UPS API's expected JSON format.
- Ensure that headers include the content-type as `application/json` and any authentication tokens retrieved earlier. Design your payload to handle dynamic input values easily.
import requests
def construct_payload(shipper, receiver, package_details, service_type):
payload = {
"UPSSecurity": {
"UsernameToken": {
"Username": "Your_Username",
"Password": "Your_Password"
},
"ServiceAccessToken": {
"AccessLicenseNumber": "Your_Access_License_Number"
}
},
"RateRequest": {
"Request": {
"RequestOption": "Rate",
"TransactionReference": {
"CustomerContext": "Your_Customer_Context"
}
},
"Shipment": {
"Shipper": shipper,
"ShipTo": receiver,
"Package": package_details,
"Service": {
"Code": service_type
}
}
}
}
return payload
Send the API Request
- Utilize the `requests` library to send the assembled JSON payload to the UPS API endpoint. Handle potential exceptions gracefully, ensuring your application can react to network issues or API errors.
- Log attempts to facilitate troubleshooting and maintain an audit trail for all requests made to the UPS system.
def get_rates(payload):
url = "https://onlinetools.ups.com/rest/Rate"
headers = {
"Content-Type": "application/json"
}
try:
response = requests.post(url, json=payload, headers=headers)
response.raise_for_status() # Ensure that we handle failed requests
# Process response
rate_info = response.json()
return rate_info
except requests.exceptions.RequestException as e:
print(f"An error occurred: {e}")
return None
Handling the API Response
- Take the JSON response from the UPS API, parsing it to extract the desired rate information. Depending on the complexity, consider converting these to meaningful Python objects or dictionaries.
- Ensure the application correctly interprets error messages from the API, presenting users or logs with clear messages to aid in troubleshooting and debugging.
def extract_rates(rate_info):
try:
# Example of extracting desired information from the response
rated_shipment = rate_info.get('RateResponse', {}).get('RatedShipment', [])
for shipment in rated_shipment:
total_cost = shipment.get('TotalCharges', {}).get('MonetaryValue')
currency = shipment.get('TotalCharges', {}).get('CurrencyCode')
print(f"Total Cost: {total_cost} {currency}")
except Exception as e:
print(f"Failed to parse rate information: {e}")
Testing and Debugging
- Ensure that the complete rate calculation workflow functions as expected. Use realistic data in a test environment (provided by UPS or sandbox if possible) to verify functionality without impacting live operations.
- Implement robust logging throughout the process to track requests and responses for future debugging. Consider integrating with logging libraries for consistent application monitoring.
