breccia-mapper/people/apps.py

import logging

from django.apps import AppConfig
from django.conf import settings
from django.core import serializers
from django.db.models.signals import post_save

logger = logging.getLogger(__name__)


def load_welcome_template_fixture(fixture_path) -> bool:
    """Load welcome email template from a JSON fixture."""
    try:
        with open(fixture_path) as f:
            for deserialized in serializers.deserialize('json', f):
                if deserialized.object.name == settings.TEMPLATE_WELCOME_EMAIL_NAME:
                    deserialized.save()
                    logger.warning('Welcome email template \'%s\' loaded', deserialized.object.name)
                    return True

            return False

    except FileNotFoundError:
        logger.warning('Email template fixture not found.')
        return False


def send_welcome_email(sender, instance, **kwargs):
    from post_office import models

    try:
        instance.send_welcome_email()

    except models.EmailTemplate.DoesNotExist:
        logger.warning('Welcome email template \'%s\' not found - attempting to load from fixtures',
                       settings.TEMPLATE_WELCOME_EMAIL_NAME)
        
        is_loaded = False
        if settings.CUSTOMISATION_NAME:
            # Customisation app present - try here first
            is_loaded |= load_welcome_template_fixture(
                settings.BASE_DIR.joinpath('custom', 'fixtures', 'email_templates.json')
            )

        # |= operator shortcuts - only try here if we don't already have it
        is_loaded |= load_welcome_template_fixture(
            settings.BASE_DIR.joinpath('people', 'fixtures', 'email_templates.json')
        )

        if is_loaded:
            instance.send_welcome_email()

        else:
            logger.error('Welcome email template \'%s\' not found', settings.TEMPLATE_WELCOME_EMAIL_NAME)


class PeopleConfig(AppConfig):
    name = 'people'
    
    def ready(self) -> None:
        # Activate signal handlers
        post_save.connect(send_welcome_email,
                          sender='people.user')