dashboard/billing/management/commands/generate_invoice.py

# Copyright © 2022 Aravinth Manivannan <realaravinth@batsense.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
from django.core.management.base import BaseCommand
from django.core.exceptions import ValidationError
from django.conf import settings
from django.core.mail import send_mail
from django.template.loader import render_to_string
from django.contrib.auth import get_user_model

from oauth2_provider.models import get_application_model
from oauth2_provider.generators import generate_client_id, generate_client_secret

from accounts.utils import gen_secret
from dash.models import Instance
from infrastructure.models import InstanceCreated
from billing.utils import generate_invoice, payment_fullfilled, get_invoice_link

Application = get_application_model()


class Command(BaseCommand):
    help = "Generate invoices, should be run from cronjob scheduled for daily execution"

    def handle(self, *args, **options):
        instances = Instance.objects.all()
        if instances:
            for paid_instance in InstanceCreated.objects.all():
                self.stdout.write(f"Found instance: {paid_instance.instance}")
                if not payment_fullfilled(instance=paid_instance.instance):
                    self.stdout.write(
                        f"Payment not fulfilled for instance: {paid_instance.instance}"
                    )
                    payment = generate_invoice(instance=paid_instance.instance)
                    owner = paid_instance.instance.owned_by
                    ctx = {
                        "username": owner.username,
                        "payment": payment,
                        "link": get_invoice_link(payment=payment),
                    }

                    body = render_to_string(
                        "billing/emails/renew-subscription.txt",
                        context=ctx,
                    )

                    email = owner.email
                    sender = settings.DEFAULT_FROM_EMAIL

                    send_mail(
                        subject="[Gna!] Payment receipt your Gna! VM",
                        message=body,
                        from_email=f"No reply Gna!<{sender}>",  # TODO read from settings.py
                        recipient_list=[email],
                    )

        else:
            self.stdout.write("No instances available")