Initial commit

app/infrastructure/ModelRepositoryImpl.py

@@ -0,0 +1,47 @@
+from sqlalchemy import select, update
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.orm import Session
+from app.domain.Exception import DuplicateModelVersionError
+from app.domain.Model import Model
+from app.domain.ModelRepository import ModelRepository
+from app.infrastructure.database import ModelRecord
+
+
+class ModelRepositoryImpl(ModelRepository):
+    def __init__(self, session: Session) -> None:
+        self._session = session
+
+    def get_latest(self) -> Model | None:
+        stmt = (
+            select(ModelRecord)
+            .order_by(ModelRecord.is_latest.desc(), ModelRecord.created_at.desc())
+            .limit(1)
+        )
+        record = self._session.scalar(stmt)
+        return record.to_domain() if record else None
+
+    def get_by_version(self, version: str) -> Model | None:
+        stmt = select(ModelRecord).where(ModelRecord.version == version)
+        record = self._session.scalar(stmt)
+        return record.to_domain() if record else None
+
+    def add(self, model: Model) -> Model:
+        record = ModelRecord(
+            version=model.version,
+            filename=model.filename,
+            file_path=model.file_path,
+            created_at=model.created_at,
+            is_latest=model.is_latest,
+        )
+        try:
+            self._session.execute(update(ModelRecord).values(is_latest=False))
+            self._session.add(record)
+            self._session.commit()
+            self._session.refresh(record)
+            return record.to_domain()
+        except IntegrityError as exc:
+            self._session.rollback()
+            raise DuplicateModelVersionError(
+                f"Model version '{model.version}' already exists."
+            ) from exc
+