Validate Checkout User Input | Dataford Interview Questions

Write a function to validate user input across multiple fields in a checkout flow.

Implement validate_checkout(fields, current_month, current_year). The input is a dictionary containing name, email, phone, address, postal_code, card_number, expiration_month, and expiration_year; return a dictionary mapping each invalid field to an error message, or {} when all fields are valid. Require nonblank name and address, a basic email with one @ and a dot in its domain, 10 to 15 phone digits, a five-digit postal code, a 13 to 19 digit card number passing Luhn validation, and an expiration date that is not earlier than the supplied current month and year.

Constraints

fields contains the eight named checkout keys
Each field value is either a string or integer as specified by its validation rule
10 <= len(phone) <= 15 for structurally valid phone inputs
13 <= len(card_number) <= 19 for structurally valid card inputs
current_month is an integer from 1 through 12
current_year is a four-digit integer

Function Signature

def validate_checkout(fields, current_month, current_year):

Your question is Validate Checkout User Input. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Write a function to validate user input across multiple fields in a checkout flow.

Constraints

fields contains the eight named checkout keys
Each field value is either a string or integer as specified by its validation rule
10 <= len(phone) <= 15 for structurally valid phone inputs
13 <= len(card_number) <= 19 for structurally valid card inputs
current_month is an integer from 1 through 12
current_year is a four-digit integer

Function Signature

def validate_checkout(fields, current_month, current_year):

Your question is Validate Checkout User Input. Start with the requirements in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.