Refactor node cache code to more easily add other types of cache.

execution.py

@@ -59,14 +59,26 @@ class IsChangedCache:
             self.is_changed[node_id] = node["is_changed"]
         return self.is_changed[node_id]
 
+
+class CacheType(Enum):
+    CLASSIC = 0
+    LRU = 1
+    DEPENDENCY_AWARE = 2
+
+
 class CacheSet:
-    def __init__(self, lru_size=None, cache_none=False):
-        if cache_none:
+    def __init__(self, cache_type=None, cache_size=None):
+        if cache_type == CacheType.DEPENDENCY_AWARE:
             self.init_dependency_aware_cache()
-        elif lru_size is None or lru_size == 0:
-            self.init_classic_cache()
+            logging.info("Disabling intermediate node cache.")
+        elif cache_type == CacheType.LRU:
+            if cache_size is None:
+                cache_size = 0
+            self.init_lru_cache(cache_size)
+            logging.info("Using LRU cache")
         else:
-            self.init_lru_cache(lru_size)
+            self.init_classic_cache()
+
         self.all = [self.outputs, self.ui, self.objects]
 
     # Performs like the old cache -- dump data ASAP
@@ -420,14 +432,14 @@ def execute(server, dynprompt, caches, current_item, extra_data, executed, promp
     return (ExecutionResult.SUCCESS, None, None)
 
 class PromptExecutor:
-    def __init__(self, server, lru_size=None, cache_none=False):
-        self.lru_size = lru_size
-        self.cache_none = cache_none
+    def __init__(self, server, cache_type=False, cache_size=None):
+        self.cache_size = cache_size
+        self.cache_type = cache_type
         self.server = server
         self.reset()
 
     def reset(self):
-        self.caches = CacheSet(self.lru_size, self.cache_none)
+        self.caches = CacheSet(cache_type=self.cache_type, cache_size=self.cache_size)
         self.status_messages = []
         self.success = True