fisk/core/lib/billing.py

import stripe
from django.conf import settings
from lago_python_client import Client
from lago_python_client.exceptions import LagoApiError
from lago_python_client.models import Customer, CustomerBillingConfiguration

client = Client(api_key=settings.LAGO_API_KEY, api_url=settings.LAGO_URL)


def expand_name(first_name, last_name):
    """
    Convert two name variables into one.
    Last name without a first name is ignored.
    :param first_name: The first name
    :param last_name: The last name
    :return: A string with the first and last name, or None if both are None
    """
    name = None
    if first_name:
        name = first_name
        # We only want to put the last name if we have a first name
        if last_name:
            name += f" {last_name}"
    return name


def get_or_create(email, first_name, last_name):
    """
    Get a customer ID from Stripe if one with the given email exists.
    Create a customer if one does not.
    Raise an exception if two or more customers matching the given email exist.
    :param email: The email address of the customer
    :param first_name: The first name of the customer
    :param last_name: The last name of the customer
    :return: The customer ID
    """
    # Let's see if we're just missing the ID
    matching_customers = stripe.Customer.list(email=email, limit=2)
    if len(matching_customers) == 2:
        # Something is horribly wrong
        raise Exception(f"Two customers found for email {email}")

    elif len(matching_customers) == 1:
        # We found a customer. Let's copy the ID
        customer = matching_customers["data"][0]
        customer_id = customer["id"]
        return customer_id

    else:
        # We didn't find anything. Create the customer

        # Create a name, since we have 2 variables which could be null
        name = expand_name(first_name, last_name)
        cast = {"email": email}
        if name:
            cast["name"] = name
        customer = stripe.Customer.create(**cast)

        return customer.id


def update_customer_fields(user):
    """
    Update the customer fields in Stripe.
    """
    stripe.Customer.modify(user.stripe_id, email=user.email)
    name = expand_name(user.first_name, user.last_name)
    stripe.Customer.modify(user.stripe_id, name=name)


def create_or_update_customer(user):
    """
    Create or update a customer in Lago.
    """
    try:
        customer = client.customers().find(str(user.customer_id))
    except LagoApiError:
        customer = None
    if not customer:
        customer = Customer(
            external_id=str(user.customer_id),
            name=f"{user.first_name} {user.last_name}",
        )

    customer.external_id = str(user.customer_id)
    customer.email = user.email
    customer.name = f"{user.first_name} {user.last_name}"
    customer.billing_configuration = CustomerBillingConfiguration(
        payment_provider="stripe",
        provider_customer_id=str(user.stripe_id),
    )

    try:
        created = client.customers().create(customer)
    except LagoApiError as e:
        print(e.response)

    lago_id = created.lago_id

    return lago_id


def delete_customer(user):
    """
    Delete a customer from Lago.
    :param user: User object to delete
    """
    try:
        client.customers().destroy(str(user.customer_id))
    except LagoApiError:
        pass