Merge pull request #338

refactor(currencies): DEPRECATE SYNTH FINANCE

app/apps/currencies/exchange_rates/fetcher.py

@@ -12,8 +12,6 @@ logger = logging.getLogger(__name__)
 
 # Map service types to provider classes
 PROVIDER_MAPPING = {
-    "synth_finance": providers.SynthFinanceProvider,
-    "synth_finance_stock": providers.SynthFinanceStockProvider,
     "coingecko_free": providers.CoinGeckoFreeProvider,
     "coingecko_pro": providers.CoinGeckoProProvider,
     "transitive": providers.TransitiveRateProvider,

app/apps/currencies/exchange_rates/providers.py

@@ -13,70 +13,6 @@ from apps.currencies.exchange_rates.base import ExchangeRateProvider
 logger = logging.getLogger(__name__)
 
 
-class SynthFinanceProvider(ExchangeRateProvider):
-    """Implementation for Synth Finance API (synthfinance.com)"""
-
-    BASE_URL = "https://api.synthfinance.com/rates/live"
-    rates_inverted = False  # SynthFinance returns non-inverted rates
-
-    def __init__(self, api_key: str = None):
-        super().__init__(api_key)
-        self.session = requests.Session()
-        self.session.headers.update({"Authorization": f"Bearer {self.api_key}"})
-
-    def get_rates(
-        self, target_currencies: QuerySet, exchange_currencies: set
-    ) -> List[Tuple[Currency, Currency, Decimal]]:
-        results = []
-        currency_groups = {}
-        for currency in target_currencies:
-            if currency.exchange_currency in exchange_currencies:
-                group = currency_groups.setdefault(currency.exchange_currency.code, [])
-                group.append(currency)
-
-        for base_currency, currencies in currency_groups.items():
-            try:
-                to_currencies = ",".join(
-                    currency.code
-                    for currency in currencies
-                    if currency.code != base_currency
-                )
-                response = self.session.get(
-                    f"{self.BASE_URL}",
-                    params={"from": base_currency, "to": to_currencies},
-                )
-                response.raise_for_status()
-                data = response.json()
-                rates = data["data"]["rates"]
-
-                for currency in currencies:
-                    if currency.code == base_currency:
-                        rate = Decimal("1")
-                    else:
-                        rate = Decimal(str(rates[currency.code]))
-                    # Return the rate as is, without inversion
-                    results.append((currency.exchange_currency, currency, rate))
-
-                credits_used = data["meta"]["credits_used"]
-                credits_remaining = data["meta"]["credits_remaining"]
-                logger.info(
-                    f"Synth Finance API call: {credits_used} credits used, {credits_remaining} remaining"
-                )
-            except requests.RequestException as e:
-                logger.error(
-                    f"Error fetching rates from Synth Finance API for base {base_currency}: {e}"
-                )
-            except KeyError as e:
-                logger.error(
-                    f"Unexpected response structure from Synth Finance API for base {base_currency}: {e}"
-                )
-            except Exception as e:
-                logger.error(
-                    f"Unexpected error processing Synth Finance data for base {base_currency}: {e}"
-                )
-        return results
-
-
 class CoinGeckoFreeProvider(ExchangeRateProvider):
     """Implementation for CoinGecko Free API"""
 
@@ -152,71 +88,6 @@ class CoinGeckoProProvider(CoinGeckoFreeProvider):
         self.session.headers.update({"x-cg-pro-api-key": api_key})
 
 
-class SynthFinanceStockProvider(ExchangeRateProvider):
-    """Implementation for Synth Finance API Real-Time Prices endpoint (synthfinance.com)"""
-
-    BASE_URL = "https://api.synthfinance.com/tickers"
-    rates_inverted = True
-
-    def __init__(self, api_key: str = None):
-        super().__init__(api_key)
-        self.session = requests.Session()
-        self.session.headers.update(
-            {"Authorization": f"Bearer {self.api_key}", "accept": "application/json"}
-        )
-
-    def get_rates(
-        self, target_currencies: QuerySet, exchange_currencies: set
-    ) -> List[Tuple[Currency, Currency, Decimal]]:
-        results = []
-
-        for currency in target_currencies:
-            if currency.exchange_currency not in exchange_currencies:
-                continue
-
-            try:
-                # Same currency has rate of 1
-                if currency.code == currency.exchange_currency.code:
-                    rate = Decimal("1")
-                    results.append((currency.exchange_currency, currency, rate))
-                    continue
-
-                # Fetch real-time price for this ticker
-                response = self.session.get(
-                    f"{self.BASE_URL}/{currency.code}/real-time"
-                )
-                response.raise_for_status()
-                data = response.json()
-
-                # Use fair market value as the rate
-                rate = Decimal(data["data"]["fair_market_value"])
-                results.append((currency.exchange_currency, currency, rate))
-
-                # Log API usage
-                credits_used = data["meta"]["credits_used"]
-                credits_remaining = data["meta"]["credits_remaining"]
-                logger.info(
-                    f"Synth Finance API call for {currency.code}: {credits_used} credits used, {credits_remaining} remaining"
-                )
-            except requests.RequestException as e:
-                logger.error(
-                    f"Error fetching rate from Synth Finance API for ticker {currency.code}: {e}",
-                    exc_info=True,
-                )
-            except KeyError as e:
-                logger.error(
-                    f"Unexpected response structure from Synth Finance API for ticker {currency.code}: {e}",
-                    exc_info=True,
-                )
-            except Exception as e:
-                logger.error(
-                    f"Unexpected error processing Synth Finance data for ticker {currency.code}: {e}",
-                    exc_info=True,
-                )
-
-        return results
-
-
 class TransitiveRateProvider(ExchangeRateProvider):
     """Calculates exchange rates through paths of existing rates"""
 
@@ -463,6 +334,10 @@ class TwelveDataProvider(ExchangeRateProvider):
 
                 logger.info(f"Successfully fetched rate for {symbol} from Twelve Data.")
 
+                time.sleep(
+                    60
+                )  # We sleep every pair as to not step over TwelveData's minute limit
+
             except requests.RequestException as e:
                 logger.error(
                     f"Error fetching rate from Twelve Data API for symbol {symbol}: {e}"
@@ -610,6 +485,10 @@ class TwelveDataMarketsProvider(ExchangeRateProvider):
                     f"Successfully processed price for {asset.code} as {final_price} {target_exchange_currency.code}"
                 )
 
+                time.sleep(
+                    60
+                )  # We sleep every pair as to not step over TwelveData's minute limit
+
             except requests.RequestException as e:
                 logger.error(
                     f"TwelveDataMarkets: API request failed for {code_value}: {e}"

app/apps/currencies/migrations/0020_migrate_synth_finance_services.py

@@ -0,0 +1,51 @@
+# Generated by Django 5.2.5 on 2025-08-17 06:25
+
+from django.db import migrations
+
+# The new value we are migrating to
+NEW_SERVICE_TYPE = "frankfurter"
+# The old values we are deprecating
+OLD_SERVICE_TYPE_TO_UPDATE = "synth_finance"
+OLD_SERVICE_TYPE_TO_DELETE = "synth_finance_stock"
+
+
+def forwards_func(apps, schema_editor):
+    """
+    Forward migration:
+    - Deletes all ExchangeRateService instances with service_type 'synth_finance_stock'.
+    - Updates all ExchangeRateService instances with service_type 'synth_finance' to 'frankfurter'.
+    """
+    ExchangeRateService = apps.get_model("currencies", "ExchangeRateService")
+    db_alias = schema_editor.connection.alias
+
+    # 1. Delete the SYNTH_FINANCE_STOCK entries
+    ExchangeRateService.objects.using(db_alias).filter(
+        service_type=OLD_SERVICE_TYPE_TO_DELETE
+    ).delete()
+
+    # 2. Update the SYNTH_FINANCE entries to FRANKFURTER
+    ExchangeRateService.objects.using(db_alias).filter(
+        service_type=OLD_SERVICE_TYPE_TO_UPDATE
+    ).update(service_type=NEW_SERVICE_TYPE, api_key=None)
+
+
+def backwards_func(apps, schema_editor):
+    """
+    Backward migration: This operation is not safely reversible.
+    - We cannot know which 'frankfurter' services were originally 'synth_finance'.
+    - The deleted 'synth_finance_stock' services cannot be recovered.
+    We will leave this function empty to allow migrating backwards without doing anything.
+    """
+    pass
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        # Add the previous migration file here
+        ("currencies", "0019_alter_exchangerateservice_service_type"),
+    ]
+
+    operations = [
+        migrations.RunPython(forwards_func, reverse_code=backwards_func),
+    ]

app/apps/currencies/migrations/0021_alter_exchangerateservice_service_type.py

@@ -0,0 +1,18 @@
+# Generated by Django 5.2.5 on 2025-08-17 06:29
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('currencies', '0020_migrate_synth_finance_services'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='exchangerateservice',
+            name='service_type',
+            field=models.CharField(choices=[('coingecko_free', 'CoinGecko (Demo/Free)'), ('coingecko_pro', 'CoinGecko (Pro)'), ('transitive', 'Transitive (Calculated from Existing Rates)'), ('frankfurter', 'Frankfurter'), ('twelvedata', 'TwelveData'), ('twelvedatamarkets', 'TwelveData Markets')], max_length=255, verbose_name='Service Type'),
+        ),
+    ]

app/apps/currencies/models.py

@@ -94,8 +94,6 @@ class ExchangeRateService(models.Model):
     """Configuration for exchange rate services"""
 
     class ServiceType(models.TextChoices):
-        SYNTH_FINANCE = "synth_finance", "Synth Finance"
-        SYNTH_FINANCE_STOCK = "synth_finance_stock", "Synth Finance Stock"
         COINGECKO_FREE = "coingecko_free", "CoinGecko (Demo/Free)"
         COINGECKO_PRO = "coingecko_pro", "CoinGecko (Pro)"
         TRANSITIVE = "transitive", "Transitive (Calculated from Existing Rates)"