feat(automatic-exchange-rate): track unsuccessful runs

app/apps/currencies/exchange_rates/fetcher.py

@@ -1,5 +1,4 @@
 import logging
-from datetime import timedelta
 
 from django.db.models import QuerySet
 from django.utils import timezone
@@ -258,7 +257,10 @@ class ExchangeRateFetcher:
                     processed_pairs.add((from_currency.id, to_currency.id))
 
             service.last_fetch = timezone.now()
+            service.failure_count = 0
             service.save()
 
         except Exception as e:
             logger.error(f"Error fetching rates for {service.name}: {e}")
+            service.failure_count += 1
+            service.save()

app/apps/currencies/migrations/0023_add_failure_count.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.2.10 on 2026-01-10 06:08
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('currencies', '0022_currency_is_archived'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='exchangerateservice',
+            name='failure_count',
+            field=models.PositiveIntegerField(default=0),
+        ),
+    ]

app/apps/currencies/models.py

@@ -136,6 +136,8 @@ class ExchangeRateService(models.Model):
         null=True, blank=True, verbose_name=_("Last Successful Fetch")
     )
 
+    failure_count = models.PositiveIntegerField(default=0)
+
     target_currencies = models.ManyToManyField(
         Currency,
         verbose_name=_("Target Currencies"),
@@ -237,7 +239,7 @@ class ExchangeRateService(models.Model):
                     hours = self._parse_hour_ranges(self.fetch_interval)
                     # Store in normalized format (optional)
                     self.fetch_interval = ",".join(str(h) for h in sorted(hours))
-                except ValueError as e:
+                except ValueError:
                     raise ValidationError(
                         {
                             "fetch_interval": _(
@@ -248,7 +250,7 @@ class ExchangeRateService(models.Model):
                     )
         except ValidationError:
             raise
-        except Exception as e:
+        except Exception:
             raise ValidationError(
                 {
                     "fetch_interval": _(

app/apps/currencies/tests/__init__.py

@@ -0,0 +1 @@
+# Tests package for currencies app

app/apps/currencies/tests/test_automatic_exchange_rates.py

@@ -0,0 +1,109 @@
+from decimal import Decimal
+from unittest.mock import patch, MagicMock
+
+from django.test import TestCase
+from django.utils import timezone
+
+from apps.currencies.models import Currency, ExchangeRateService
+from apps.currencies.exchange_rates.fetcher import ExchangeRateFetcher
+
+
+class ExchangeRateServiceFailureTrackingTests(TestCase):
+    """Tests for the failure count tracking functionality."""
+
+    def setUp(self):
+        """Set up test data."""
+        self.usd = Currency.objects.create(
+            code="USD", name="US Dollar", decimal_places=2, prefix="$ "
+        )
+        self.eur = Currency.objects.create(
+            code="EUR", name="Euro", decimal_places=2, prefix="€ "
+        )
+        self.eur.exchange_currency = self.usd
+        self.eur.save()
+
+        self.service = ExchangeRateService.objects.create(
+            name="Test Service",
+            service_type=ExchangeRateService.ServiceType.FRANKFURTER,
+            is_active=True,
+        )
+        self.service.target_currencies.add(self.eur)
+
+    def test_failure_count_increments_on_provider_error(self):
+        """Test that failure_count increments when provider raises an exception."""
+        self.assertEqual(self.service.failure_count, 0)
+
+        with patch.object(
+            self.service, "get_provider", side_effect=Exception("API Error")
+        ):
+            ExchangeRateFetcher._fetch_service_rates(self.service)
+
+        self.service.refresh_from_db()
+        self.assertEqual(self.service.failure_count, 1)
+
+    def test_failure_count_resets_on_success(self):
+        """Test that failure_count resets to 0 on successful fetch."""
+        # Set initial failure count
+        self.service.failure_count = 5
+        self.service.save()
+
+        # Mock a successful provider
+        mock_provider = MagicMock()
+        mock_provider.requires_api_key.return_value = False
+        mock_provider.get_rates.return_value = [(self.usd, self.eur, Decimal("0.85"))]
+        mock_provider.rates_inverted = False
+
+        with patch.object(self.service, "get_provider", return_value=mock_provider):
+            ExchangeRateFetcher._fetch_service_rates(self.service)
+
+        self.service.refresh_from_db()
+        self.assertEqual(self.service.failure_count, 0)
+
+    def test_failure_count_accumulates_across_fetches(self):
+        """Test that failure_count accumulates with consecutive failures."""
+        self.assertEqual(self.service.failure_count, 0)
+
+        with patch.object(
+            self.service, "get_provider", side_effect=Exception("API Error")
+        ):
+            ExchangeRateFetcher._fetch_service_rates(self.service)
+            self.service.refresh_from_db()
+            self.assertEqual(self.service.failure_count, 1)
+
+            ExchangeRateFetcher._fetch_service_rates(self.service)
+            self.service.refresh_from_db()
+            self.assertEqual(self.service.failure_count, 2)
+
+            ExchangeRateFetcher._fetch_service_rates(self.service)
+            self.service.refresh_from_db()
+            self.assertEqual(self.service.failure_count, 3)
+
+    def test_last_fetch_not_updated_on_failure(self):
+        """Test that last_fetch is NOT updated when a failure occurs."""
+        original_last_fetch = self.service.last_fetch
+        self.assertIsNone(original_last_fetch)
+
+        with patch.object(
+            self.service, "get_provider", side_effect=Exception("API Error")
+        ):
+            ExchangeRateFetcher._fetch_service_rates(self.service)
+
+        self.service.refresh_from_db()
+        self.assertIsNone(self.service.last_fetch)
+        self.assertEqual(self.service.failure_count, 1)
+
+    def test_last_fetch_updated_on_success(self):
+        """Test that last_fetch IS updated when fetch succeeds."""
+        self.assertIsNone(self.service.last_fetch)
+
+        mock_provider = MagicMock()
+        mock_provider.requires_api_key.return_value = False
+        mock_provider.get_rates.return_value = [(self.usd, self.eur, Decimal("0.85"))]
+        mock_provider.rates_inverted = False
+
+        with patch.object(self.service, "get_provider", return_value=mock_provider):
+            ExchangeRateFetcher._fetch_service_rates(self.service)
+
+        self.service.refresh_from_db()
+        self.assertIsNotNone(self.service.last_fetch)
+        self.assertEqual(self.service.failure_count, 0)

app/templates/exchange_rates_services/fragments/list.html

@@ -56,7 +56,15 @@
                 </td>
                 <td class="table-col-auto">{% if service.is_active %}<i class="fa-solid fa-circle text-success"></i>{% else %}
                   <i class="fa-solid fa-circle text-error"></i>{% endif %}</td>
-                <td class="table-col-auto">{{ service.name }}</td>
+                <td>
+                  {{ service.name }}
+                  {% if service.failure_count > 0 %}
+                    <span class="badge badge-error gap-1" data-tippy-content="{% blocktrans count counter=service.failure_count %}{{ counter }} consecutive failure{% plural %}{{ counter }} consecutive failures{% endblocktrans %}">
+                      <i class="fa-solid fa-triangle-exclamation fa-fw"></i>
+                      {{ service.failure_count }}
+                    </span>
+                  {% endif %}
+                </td>
                 <td>{{ service.get_service_type_display }}</td>
                 <td>{{ service.target_currencies.count }} {% trans 'currencies' %}, {{ service.target_accounts.count }} {% trans 'accounts' %}</td>
                 <td>{{ service.last_fetch|date:"SHORT_DATETIME_FORMAT" }}</td>