add query.py

affine/query.py

@@ -0,0 +1,27 @@
+from typing import TYPE_CHECKING, Type
+
+from affine.collection import Collection, Filter, FilterSet
+
+if TYPE_CHECKING:
+    from affine.engine import Engine
+
+
+class QueryObject:
+    def __init__(self, db: "Engine", collection_class: Type[Collection]):
+        self.db = db
+        self.collection_class = collection_class
+
+    def filter(self, filter_set: FilterSet | Filter) -> list[Collection]:
+        if isinstance(filter_set, Filter):
+            filter_set = FilterSet(
+                filters=[filter_set], collection=filter_set.collection
+            )
+        return self.db._query(filter_set)
+
+    def all(self) -> list[Collection]:
+        return self.db._query(
+            FilterSet(filters=[], collection=self.collection_class.__name__)
+        )
+
+    def get_by_id(self, id_) -> Collection:
+        return self.db.get_element_by_id(self.collection_class, id_)