specify protocol operations and affected data

Hash2Pub/src/Hash2Pub/FediChord.hs

@@ -99,7 +99,7 @@ data NodeState = NodeState {
   , nodeCache :: NodeCache
   -- ^ EpiChord node cache with expiry times for nodes
   -- as the map is ordered, lookups for the closes preceding node can be done using @lookupLT@
-  , successors :: [NodeID]
+  , successors :: [NodeID] -- could be a set instead as these are ordered as well
   , predecessors :: [NodeID]
   ----- protocol parameters -----
   -- TODO: evaluate moving these somewhere else
@@ -121,9 +121,10 @@ type NodeCache = Map.Map NodeID CacheEntry
 
 -- |an entry of the 'nodeCache'
 type CacheEntry = (
-    NodeState
+    Bool
+  , NodeState
   , SystemTime
-                  )   -- ^ ( a node's data, timestamp for cache entry expiration )
+                  )   -- ^ ( a node's validation status, data, timestamp for cache entry expiration )
 
 -- | generates a 256 bit long NodeID using SHAKE128, represented as ByteString
 genNodeIDBS :: HostAddress6     -- ^a node's IPv6 address
@@ -202,7 +203,7 @@ checkCacheSlices state =
                   diff = getNodeID $ upperBound - ownID
                   lowerBound = ownID + NodeID (diff `div` 2)
                 in
-                   -- TODO: replace empty IO actions with actual lookups
+                   -- TODO: replace empty IO actions with actual lookups to middle of slice
                    -- TODO: validate ID before adding to cache
                    case Map.lookupLT upperBound cache of
                        Nothing -> return () : checkSlice j ownID lowerBound (Just lastSuccNode) cache