Refactored some stuff

services/base.py

@@ -1,7 +0,0 @@
-from abc import ABC, abstractmethod
-from uuid import UUID
-
-
-class Service(ABC):
-    def __init__(self, model: UUID):
-        self.model = model

services/bottom/V0.py

@@ -1,11 +1,10 @@
-from services.base import Service, UUID
+from uuid import UUID
 from state.base import State
 from typing import Any, List
 
 
-class Bottom(Service):
-    def __init__(self, model: UUID, state: State):
-        super().__init__(model)
+class Bottom:
+    def __init__(self, state: State):
         self.state = state
 
     def create_node(self, value=None) -> UUID:
@@ -20,9 +19,6 @@ class Bottom(Service):
         else:
             return self.state.create_dict(source, label, target)
 
-    def read_model_root(self) -> UUID:
-        return self.model
-
     def read_value(self, node: UUID) -> Any:
         return self.state.read_value(node)
 
@@ -68,6 +64,20 @@ class Bottom(Service):
             edges = [e for e in edges if read_label(e) == label]
         return edges
 
+    def read_incoming_nodes(self, target: UUID, label=None) -> List[UUID]:
+        edges = self.read_incoming_edges(target, label)
+        if edges is None or len(edges) == 0:
+            return []
+        else:
+            return [self.read_edge_source(e) for e in edges]
+
+    def read_outgoing_nodes(self, source: UUID, label=None) -> List[UUID]:
+        edges = self.read_outgoing_edges(source, label)
+        if edges is None or len(edges) == 0:
+            return []
+        else:
+            return [self.read_edge_target(e) for e in edges]
+
     def read_keys(self, element: UUID) -> List[str]:
         key_nodes = self.state.read_dict_keys(element)
         unique_keys = {self.state.read_value(node) for node in key_nodes}