feat: expand platform APIs, sources, and test coverage

tests/apps/exchange/test_models.py

@@ -0,0 +1,27 @@
+"""Tests for exchange models."""
+
+from apps.exchange.models import ExchangeConnection
+from django.test import TestCase
+
+from tests.apps.exchange.factories import ExchangeConnectionFactory
+
+
+class ExchangeConnectionModelTest(TestCase):
+    def test_string_representation_and_plain_password_passthrough(self):
+        connection = ExchangeConnectionFactory(
+            username="postgres",
+            server="127.0.0.1",
+            port=5432,
+            database_name="target_db",
+            schema_name="public",
+        )
+
+        self.assertEqual(str(connection), "postgres@127.0.0.1:5432/target_db[public]")
+        self.assertEqual(ExchangeConnection.decrypt_password("legacy-pass"), "legacy-pass")
+
+    def test_decrypt_password_raises_for_invalid_encrypted_token(self):
+        with self.assertRaisesMessage(
+            ValueError,
+            "Не удалось расшифровать пароль exchange connection",
+        ):
+            ExchangeConnection.decrypt_password(f"{ExchangeConnection.PASSWORD_PREFIX}invalid")