Adds Loader, DatabaseLoader and (Db)Client

Adds unit test to test interfaces.

pfbudget/db/client.py

@@ -0,0 +1,11 @@
+from typing import Sequence
+
+from pfbudget.db.model import Transaction
+
+
+class Client:
+    def __init__(self, url: str) -> None:
+        self.url = url
+
+    def insert(self, transactions: Sequence[Transaction]) -> None:
+        raise NotImplementedError

pfbudget/load/database.py

@@ -0,0 +1,14 @@
+from typing import Sequence
+
+from pfbudget.db.client import Client
+from pfbudget.db.model import Transaction
+
+from .load import Loader
+
+
+class DatabaseLoader(Loader):
+    def __init__(self, client: Client) -> None:
+        self.client = client
+
+    def load(self, transactions: Sequence[Transaction]) -> None:
+        self.client.insert(transactions)

pfbudget/load/load.py

@@ -0,0 +1,10 @@
+from abc import ABC, abstractmethod
+from typing import Sequence
+
+from pfbudget.db.model import Transaction
+
+
+class Loader(ABC):
+    @abstractmethod
+    def load(self, transactions: Sequence[Transaction]) -> None:
+        raise NotImplementedError

tests/test_load.py

@@ -0,0 +1,37 @@
+from datetime import date
+from decimal import Decimal
+from typing import Sequence
+import pytest
+
+from pfbudget.db.client import Client
+from pfbudget.db.model import BankTransaction, Transaction
+from pfbudget.load.database import DatabaseLoader
+from pfbudget.load.load import Loader
+
+
+class FakeDatabaseClient(Client):
+    def __init__(self, url: str) -> None:
+        super().__init__(url)
+
+    def insert(self, transactions: Sequence[Transaction]) -> None:
+        pass
+
+
+@pytest.fixture
+def loader() -> Loader:
+    url = "postgresql://user:pass@127.0.0.1:5432/db"
+    client = FakeDatabaseClient(url)
+    return DatabaseLoader(client)
+
+
+class TestDatabaseLoad:
+    def test_empty_url(self):
+        _ = FakeDatabaseClient("")
+
+    def test_insert(self, loader: Loader):
+        transactions = [
+            BankTransaction(date(2023, 1, 1), "", Decimal("-500"), "Bank#1"),
+            BankTransaction(date(2023, 1, 2), "", Decimal("500"), "Bank#2"),
+        ]
+
+        loader.load(transactions)