+ CurrencyAPIClient for fresh CNY rate

+ yuan_rate_last_updated, yuan_rate_commission fields in GlobalSettings

external_api/currency.py

@@ -0,0 +1,57 @@
+from decimal import Decimal
+from contextlib import suppress
+from urllib.parse import urljoin
+
+import requests
+from django.conf import settings
+
+
+class CurrencyAPIClient:
+    CONVERT_ENDPOINT = 'currency/convert'
+
+    MAX_RETRIES = 2
+
+    def __init__(self, api_key: str):
+        self.api_url = 'https://api.getgeoapi.com/v2/'
+        self.api_key = api_key
+        self.session = requests.Session()
+
+    def request(self, method, url, *args, **kwargs):
+        params = kwargs.pop('params', {})
+        params.update({"api_key": self.api_key})
+
+        joined_url = urljoin(self.api_url, url)
+        request = requests.Request(method, joined_url, params=params, *args, **kwargs)
+
+        retries = 0
+        while retries < self.MAX_RETRIES:
+            retries += 1
+            prepared = self.session.prepare_request(request)
+            r = self.session.send(prepared)
+
+            # TODO: handle/log errors
+            return r
+
+    def get_rate(self, currency1: str, currency2: str, amount=1):
+        params = {
+            'from': currency1,
+            'to': currency2,
+            'amount': amount,
+            'format': 'json'
+        }
+
+        r = self.request('GET', self.CONVERT_ENDPOINT, params=params)
+        if not r or r.json().get('status') == 'failed':
+            return None
+
+        with suppress(KeyError):
+            rate = r.json()['rates'][currency2.upper()]['rate']
+            return Decimal(rate)
+
+        return None
+
+    def get_cny_rate(self):
+        return self.get_rate('cny', 'rub')
+
+
+client = CurrencyAPIClient(settings.CURRENCY_GETGEOIP_API_KEY)

poizonstore/settings.py

@@ -29,6 +29,8 @@ CDEK_CLIENT_SECRET = 'lc2gmrmK5s1Kk6FhZbNqpQCaATQRlsOy'
 
 POIZON_TOKEN = 'IRwNgBxb8YQ'
 
+CURRENCY_GETGEOIP_API_KEY = '136a69df7e4f419c97783288068e5a2f1ef4ad6d'
+
 # SECURITY WARNING: don't run with debug turned on in production!
 DEBUG = bool(int(os.environ.get("DJANGO_DEBUG") or 0))
 DISABLE_PERMISSIONS = False
@@ -198,6 +200,7 @@ DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'
 
 CHECKLIST_ID_LENGTH = 10
 COMMISSION_OVER_150K = 1.1
+YUAN_RATE_UPDATE_PERIOD_MINUTES = 60
 
 # Logging
 SENTRY_DSN = "https://96106e3f938badc86ecb2e502716e496@o4506163299418112.ingest.sentry.io/4506163300663296"

store/migrations/0048_globalsettings_yuan_rate_commission_and_more.py

@@ -0,0 +1,23 @@
+# Generated by Django 4.2.2 on 2023-11-22 22:15
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('store', '0047_alter_checklist_gift'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='globalsettings',
+            name='yuan_rate_commission',
+            field=models.DecimalField(decimal_places=2, default=0, max_digits=10, verbose_name='Наценка на курс юаня, руб'),
+        ),
+        migrations.AddField(
+            model_name='globalsettings',
+            name='yuan_rate_last_updated',
+            field=models.DateTimeField(default=None, null=True, verbose_name='Дата обновления курса CNY/RUB'),
+        ),
+    ]

store/models.py

@@ -23,6 +23,7 @@ from django_cleanup import cleanup
 from mptt.fields import TreeForeignKey
 from mptt.models import MPTTModel
 
+from external_api.currency import client as CurrencyAPIClient
 from store.utils import create_preview, concat_not_null_values
 from utils.cache import InMemoryCache
 
@@ -30,6 +31,8 @@ from utils.cache import InMemoryCache
 class GlobalSettings(models.Model):
     # currency
     yuan_rate = models.DecimalField('Курс CNY/RUB', max_digits=10, decimal_places=2, default=0)
+    yuan_rate_last_updated = models.DateTimeField('Дата обновления курса CNY/RUB', null=True, default=None)
+    yuan_rate_commission = models.DecimalField('Наценка на курс юаня, руб', max_digits=10, decimal_places=2, default=0)
     # Chinadelivery
     delivery_price_CN = models.DecimalField('Цена доставки по Китаю', max_digits=10, decimal_places=2, default=0)
     commission_rub = models.DecimalField('Комиссия, руб', max_digits=10, decimal_places=2, default=0)
@@ -63,6 +66,26 @@ class GlobalSettings(models.Model):
         InMemoryCache.set('GlobalSettings', obj)
         return obj
 
+    def get_yuan_rate(self):
+        """ Get rate either from CurrencyAPI or from DB (if fresh enough) """
+        if self.yuan_rate_last_updated is not None:
+            diff_minutes = (timezone.now() - self.yuan_rate_last_updated).total_seconds() / 60
+        else:
+            diff_minutes = None
+
+        if diff_minutes is None or diff_minutes > settings.YUAN_RATE_UPDATE_PERIOD_MINUTES:
+            # Get fresh rate from API
+            rate = CurrencyAPIClient.get_cny_rate()
+            if rate:
+                # Save rate in DB for future usage
+                self.yuan_rate = rate
+                self.yuan_rate_last_updated = timezone.now()
+                self.save()
+                return rate
+
+        # Default
+        return self.yuan_rate
+
 
 class Category(MPTTModel):
     name = models.CharField('Название', max_length=20)
@@ -271,7 +294,7 @@ class ChecklistQuerySet(models.QuerySet):
         return self.annotate(
             _yuan_rate=Case(
                 When(price_snapshot_id__isnull=False, then=F('price_snapshot__yuan_rate')),
-                default=GlobalSettings.load().yuan_rate
+                default=GlobalSettings.load().get_yuan_rate()
             ),
             _price_rub=Ceil(F('_yuan_rate') * F('price_yuan'))
         )
@@ -448,7 +471,7 @@ class Checklist(models.Model):
         if self.price_snapshot_id:
             yuan_rate = self.price_snapshot.yuan_rate
         else:
-            yuan_rate = GlobalSettings.load().yuan_rate
+            yuan_rate = GlobalSettings.load().get_yuan_rate()
 
         return math.ceil(yuan_rate * self.price_yuan)
 
@@ -483,7 +506,7 @@ class Checklist(models.Model):
         if self.price_snapshot_id:
             return self.price_snapshot.yuan_rate
         else:
-            return GlobalSettings.load().yuan_rate
+            return GlobalSettings.load().get_yuan_rate()
 
     @property
     def delivery_price_CN(self) -> Decimal:

store/serializers.py

@@ -206,14 +206,14 @@ class AnonymousUserChecklistSerializer(ChecklistSerializer):
 
 
 class GlobalSettingsSerializer(serializers.ModelSerializer):
-    currency = serializers.DecimalField(source='yuan_rate', max_digits=10, decimal_places=2)
+    currency = serializers.DecimalField(source='get_yuan_rate', read_only=True, max_digits=10, decimal_places=2)
     chinadelivery = serializers.DecimalField(source='delivery_price_CN', max_digits=10, decimal_places=2)
     commission = serializers.DecimalField(source='commission_rub', max_digits=10, decimal_places=2)
     pickup = serializers.CharField(source='pickup_address')
 
     class Meta:
         model = GlobalSettings
-        fields = ('currency', 'commission', 'chinadelivery', 'pickup', 'time_to_buy')
+        fields = ('currency', 'yuan_rate_commission', 'commission',  'chinadelivery', 'pickup', 'time_to_buy')
 
 
 class PaymentMethodSerializer(serializers.ModelSerializer):

store/views.py

@@ -202,7 +202,7 @@ class StatisticsAPI(viewsets.GenericViewSet):
     @action(url_path='orders', detail=False, methods=['get'])
     def stats_by_orders(self, request, *args, **kwargs):
         global_settings = GlobalSettings.load()
-        yuan_rate = global_settings.yuan_rate
+        yuan_rate = global_settings.get_yuan_rate()
 
         # Prepare query to collect the stats
         qs = self.get_queryset() \