[Refactor] Database client interface changed

`add` method replaced with `insert`.
`insert` and `select` implemented for new database base class.
Database unit test added.

Due to SQLite implementation of the primary key autoinc, the type of the
IDs on the database for SQLite changed to Integer.
https://www.sqlite.org/autoinc.html

pfbudget/cli/interactive.py

@@ -57,7 +57,7 @@ class Interactive:
 
                     case "split":
                         new = self.split(next)
-                        session.add(new)
+                        session.insert(new)
 
                     case other:
                         if not other:
@@ -84,7 +84,7 @@ class Interactive:
                             )
                             for tag in tags:
                                 if tag not in [t.name for t in self.tags]:
-                                    session.add([Tag(tag)])
+                                    session.insert([Tag(tag)])
                                     self.tags = session.get(Tag)
 
                                 next.tags.add(TransactionTag(tag))

pfbudget/core/manager.py

@@ -72,7 +72,7 @@ class Manager:
                     and input(f"{transactions[:5]}\nCommit? (y/n)") == "y"
                 ):
                     with self.db.session() as session:
-                        session.add(sorted(transactions))
+                        session.insert(sorted(transactions))
 
             case Operation.Download:
                 client = Manager.nordigen_client()
@@ -91,7 +91,7 @@ class Manager:
                 # dry-run
                 if not params[2]:
                     with self.db.session() as session:
-                        session.add(sorted(transactions))
+                        session.insert(sorted(transactions))
                 else:
                     print(sorted(transactions))
 
@@ -149,7 +149,7 @@ class Manager:
                 | Operation.TagRuleAdd
             ):
                 with self.db.session() as session:
-                    session.add(params)
+                    session.insert(params)
 
             case Operation.CategoryUpdate:
                 with self.db.session() as session:
@@ -184,7 +184,7 @@ class Manager:
 
             case Operation.GroupAdd:
                 with self.db.session() as session:
-                    session.add(params)
+                    session.insert(params)
 
             case Operation.GroupRemove:
                 assert all(isinstance(param, CategoryGroup) for param in params)
@@ -217,7 +217,7 @@ class Manager:
                             link.category = original.category
 
                     tobelinked = [Link(original.id, link.id) for link in links]
-                    session.add(tobelinked)
+                    session.insert(tobelinked)
 
             case Operation.Dismantle:
                 assert all(isinstance(param, Link) for param in params)
@@ -260,7 +260,7 @@ class Manager:
                         splitted.category = t.category
                         transactions.append(splitted)
 
-                    session.add(transactions)
+                    session.insert(transactions)
 
             case Operation.Export:
                 with self.db.session() as session:
@@ -298,7 +298,7 @@ class Manager:
 
                 if self.certify(transactions):
                     with self.db.session() as session:
-                        session.add(transactions)
+                        session.insert(transactions)
 
             case Operation.ExportBanks:
                 with self.db.session() as session:
@@ -314,7 +314,7 @@ class Manager:
 
                 if self.certify(banks):
                     with self.db.session() as session:
-                        session.add(banks)
+                        session.insert(banks)
 
             case Operation.ExportCategoryRules:
                 with self.db.session() as session:
@@ -325,7 +325,7 @@ class Manager:
 
                 if self.certify(rules):
                     with self.db.session() as session:
-                        session.add(rules)
+                        session.insert(rules)
 
             case Operation.ExportTagRules:
                 with self.db.session() as session:
@@ -336,7 +336,7 @@ class Manager:
 
                 if self.certify(rules):
                     with self.db.session() as session:
-                        session.add(rules)
+                        session.insert(rules)
 
             case Operation.ExportCategories:
                 with self.db.session() as session:
@@ -360,7 +360,7 @@ class Manager:
 
                 if self.certify(categories):
                     with self.db.session() as session:
-                        session.add(categories)
+                        session.insert(categories)
 
             case Operation.ExportCategoryGroups:
                 with self.db.session() as session:
@@ -373,7 +373,7 @@ class Manager:
 
                 if self.certify(groups):
                     with self.db.session() as session:
-                        session.add(groups)
+                        session.insert(groups)
 
     def parse(self, filename: Path, args: dict):
         return parse_data(filename, args)

pfbudget/db/client.py

@@ -1,11 +1,70 @@
-from typing import Sequence
+from sqlalchemy import Engine, create_engine, select, text
+from sqlalchemy.orm import Session, sessionmaker
+from typing import Any, Optional, Sequence, Type, TypeVar
+from pfbudget.db.exceptions import InsertError, SelectError
 
 from pfbudget.db.model import Transaction
 
 
 class Client:
-    def __init__(self, url: str) -> None:
+    def __init__(self, url: str, **kwargs: dict[str, Any]) -> None:
-        self.url = url
+        assert url, "Database URL is empty!"
+        self._engine = create_engine(url, **kwargs)
+        self._sessionmaker: Optional[sessionmaker[Session]] = None
 
-    def insert(self, transactions: Sequence[Transaction]) -> None:
+    def insert(
-        raise NotImplementedError
+        self, transactions: Sequence[Transaction], session: Optional[Session] = None
+    ) -> None:
+        if not session:
+            with self.session as session_:
+                try:
+                    session_.add_all(transactions)
+                except Exception as e:
+                    session_.rollback()
+                    raise InsertError(e)
+                else:
+                    session_.commit()
+        else:
+            try:
+                session.add_all(transactions)
+            except Exception as e:
+                session.rollback()
+                raise InsertError(e)
+            else:
+                session.commit()
+
+    T = TypeVar("T")
+
+    def select(self, what: Type[T], session: Optional[Session] = None) -> Sequence[T]:
+        stmt = select(what)
+        result: Sequence[what] = []
+
+        if not session:
+            with self.session as session_:
+                try:
+                    result = session_.scalars(stmt).all()
+                except Exception as e:
+                    session_.rollback()
+                    raise SelectError(e)
+                else:
+                    session_.commit()
+        else:
+            try:
+                result = session.scalars(stmt).all()
+            except Exception as e:
+                session.rollback()
+                raise SelectError(e)
+            else:
+                session.commit()
+
+        return result
+
+    @property
+    def engine(self) -> Engine:
+        return self._engine
+
+    @property
+    def session(self) -> Session:
+        if not self._sessionmaker:
+            self._sessionmaker = sessionmaker(self._engine)
+        return self._sessionmaker()

pfbudget/db/exceptions.py

@@ -0,0 +1,6 @@
+class InsertError(Exception):
+    pass
+
+
+class SelectError(Exception):
+    pass

pfbudget/db/model.py

@@ -9,6 +9,7 @@ from sqlalchemy import (
     BigInteger,
     Enum,
     ForeignKey,
+    Integer,
     MetaData,
     Numeric,
     String,
@@ -78,7 +79,14 @@ class Bank(Base, Export):
 
 bankfk = Annotated[str, mapped_column(Text, ForeignKey(Bank.name))]
 
-idpk = Annotated[int, mapped_column(BigInteger, primary_key=True, autoincrement=True)]
+idpk = Annotated[
+    int,
+    mapped_column(
+        BigInteger().with_variant(Integer, "sqlite"),
+        primary_key=True,
+        autoincrement=True,
+    ),
+]
 money = Annotated[decimal.Decimal, mapped_column(Numeric(16, 2))]
 
 

pfbudget/db/postgresql.py

@@ -78,7 +78,7 @@ class DbClient:
             )
             return self.__session.scalars(stmt).all()
 
-        def add(self, rows: list):
+        def insert(self, rows: list):
             self.__session.add_all(rows)
 
         def remove_by_name(self, type, rows: list):

tests/test_database.py

@@ -0,0 +1,29 @@
+from datetime import date
+from decimal import Decimal
+import pytest
+
+from pfbudget.db.client import Client
+from pfbudget.db.model import Base, Transaction
+
+
+@pytest.fixture
+def client() -> Client:
+    url = "sqlite://"
+    client = Client(url, execution_options={"schema_translate_map": {"pfbudget": None}})
+    Base.metadata.create_all(client.engine)
+    return client
+
+
+class TestDatabase:
+    def test_initialization(self, client: Client):
+        pass
+
+    def test_insert_transactions(self, client: Client):
+        transactions = [
+            Transaction(date(2023, 1, 1), "", Decimal("-500")),
+            Transaction(date(2023, 1, 2), "", Decimal("500")),
+        ]
+
+        with client.session as session:
+            client.insert(transactions, session)
+            assert client.select(Transaction, session) == transactions

tests/test_load.py

@@ -26,6 +26,7 @@ def loader() -> Loader:
 
 class TestDatabaseLoad:
     def test_empty_url(self):
+        with pytest.raises(AssertionError):
             _ = FakeDatabaseClient("")
 
     def test_insert(self, loader: Loader):