Feat/malware scanning (#120)

* Introduce malware scanner base class

* Force malware scanner to be part of ingestor composition

* Rename property to make more sense in context

* Don't include abstract class in test coverage

meldingen_core/image.py

@@ -1,6 +1,7 @@
 from abc import ABCMeta, abstractmethod  # pragma: no cover
 from typing import AsyncIterator, Generic, TypeVar
 
+from meldingen_core.malware import BaseMalwareScanner
 from meldingen_core.models import Attachment
 
 
@@ -17,6 +18,11 @@ async def __call__(self, image_path: str) -> str: ...
 T = TypeVar("T", bound=Attachment)
 
 
-class BaseIngestor(Generic[T], metaclass=ABCMeta):
+class BaseIngestor(Generic[T], metaclass=ABCMeta):  # pragma: no cover
+    _scan_for_malware: BaseMalwareScanner
+
+    def __init__(self, scanner: BaseMalwareScanner):
+        self._scan_for_malware = scanner
+
     @abstractmethod
     async def __call__(self, attachment: T, data: AsyncIterator[bytes]) -> None: ...

meldingen_core/malware.py

@@ -0,0 +1,12 @@
+from abc import ABCMeta, abstractmethod
+
+
+class MalwareException(Exception): ...
+
+
+class MalwareFoundException(MalwareException): ...
+
+
+class BaseMalwareScanner(metaclass=ABCMeta):
+    @abstractmethod
+    async def __call__(self, file_path: str) -> None: ...