use HistoryEntry for deps

library/events/json_missing_dependencies_event.nim

@@ -1,15 +1,15 @@
 import std/json
-import ./json_base_event, ../../src/[message]
+import ./json_base_event, ../../src/[message], std/base64
 
 type JsonMissingDependenciesEvent* = ref object of JsonEvent
   messageId*: SdsMessageID
-  missingDeps: seq[SdsMessageID]
+  missingDeps*: seq[HistoryEntry]
   channelId*: SdsChannelID
 
 proc new*(
     T: type JsonMissingDependenciesEvent,
     messageId: SdsMessageID,
-    missingDeps: seq[SdsMessageID],
+    missingDeps: seq[HistoryEntry],
     channelId: SdsChannelID,
 ): T =
   return JsonMissingDependenciesEvent(
@@ -17,4 +17,15 @@ proc new*(
   )
 
 method `$`*(jsonMissingDependencies: JsonMissingDependenciesEvent): string =
-  $(%*jsonMissingDependencies)
+  var node = newJObject()
+  node["eventType"] = %*jsonMissingDependencies.eventType
+  node["messageId"] = %*jsonMissingDependencies.messageId
+  node["channelId"] = %*jsonMissingDependencies.channelId
+  var missingDepsNode = newJArray()
+  for dep in jsonMissingDependencies.missingDeps:
+    var depNode = newJObject()
+    depNode["messageId"] = %*dep.messageId
+    depNode["retrievalHint"] = %*encode(dep.retrievalHint)
+    missingDepsNode.add(depNode)
+  node["missingDeps"] = missingDepsNode
+  $node

library/libsds.nim

@@ -82,7 +82,7 @@ proc onMessageSent(ctx: ptr SdsContext): MessageSentCallback =
       $JsonMessageSentEvent.new(messageId, channelId)
 
 proc onMissingDependencies(ctx: ptr SdsContext): MissingDependenciesCallback =
-  return proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+  return proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
     callEventCallback(ctx, "onMissingDependencies"):
       $JsonMissingDependenciesEvent.new(messageId, missingDeps, channelId)
 

library/sds_thread/inter_thread_communication/requests/sds_lifecycle_request.nim

@@ -40,6 +40,7 @@ proc createReliabilityManager(
   rm.setCallbacks(
     appCallbacks.messageReadyCb, appCallbacks.messageSentCb,
     appCallbacks.missingDependenciesCb, appCallbacks.periodicSyncCb,
+    appCallbacks.retrievalHintProvider,
   )
 
   return ok(rm)

library/sds_thread/inter_thread_communication/requests/sds_message_request.nim

@@ -1,4 +1,4 @@
-import std/[json, strutils, net, sequtils]
+import std/[json, strutils, net, sequtils, base64]
 import chronos, chronicles, results
 
 import ../../../alloc
@@ -17,7 +17,7 @@ type SdsMessageRequest* = object
 
 type SdsUnwrapResponse* = object
   message*: seq[byte]
-  missingDeps*: seq[SdsMessageID]
+  missingDeps*: seq[HistoryEntry]
 
 proc createShared*(
     T: type SdsMessageRequest,
@@ -61,13 +61,23 @@ proc process*(
   of UNWRAP_MESSAGE:
     let messageBytes = self.message.toSeq()
 
-    let (unwrappedMessage, missingDeps, _) = unwrapReceivedMessage(rm[], messageBytes).valueOr:
+    let (unwrappedMessage, missingDeps, extractedChannelId) = unwrapReceivedMessage(rm[], messageBytes).valueOr:
       error "UNWRAP_MESSAGE failed", error = error
       return err("error processing UNWRAP_MESSAGE request: " & $error)
 
-    let res = SdsUnwrapResponse(message: unwrappedMessage, missingDeps: missingDeps.getMessageIds())
+    let res = SdsUnwrapResponse(message: unwrappedMessage, missingDeps: missingDeps)
 
     # return the result as a json string
-    return ok($(%*(res)))
+    var node = newJObject()
+    node["message"] = %*res.message
+    node["channelId"] = %*extractedChannelId
+    var missingDepsNode = newJArray()
+    for dep in res.missingDeps:
+      var depNode = newJObject()
+      depNode["messageId"] = %*dep.messageId
+      depNode["retrievalHint"] = %*encode(dep.retrievalHint)
+      missingDepsNode.add(depNode)
+    node["missingDeps"] = missingDepsNode
+    return ok($node)
 
   return ok("")

src/reliability.nim

@@ -226,7 +226,7 @@ proc unwrapReceivedMessage*(
       channel.incomingBuffer[msg.messageId] =
         IncomingMessage(message: msg, missingDeps: missingDeps.getMessageIds().toHashSet())
       if not rm.onMissingDependencies.isNil():
-        rm.onMissingDependencies(msg.messageId, missingDeps.getMessageIds(), channelId)
+        rm.onMissingDependencies(msg.messageId, missingDeps, channelId)
 
     return ok((msg.content, missingDeps, channelId))
   except Exception:

src/reliability_utils.nim

@@ -10,7 +10,7 @@ type
     proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.}
 
   MissingDependenciesCallback* = proc(
-    messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID
+    messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID
   ) {.gcsafe.}
 
   RetrievalHintProvider* = proc(messageId: SdsMessageID): seq[byte] {.gcsafe.}
@@ -48,7 +48,7 @@ type
     onMessageReady*: proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.}
     onMessageSent*: proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.}
     onMissingDependencies*: proc(
-      messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID
+      messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID
     ) {.gcsafe.}
     onPeriodicSync*: PeriodicSyncCallback
     onRetrievalHint*: RetrievalHintProvider
@@ -153,9 +153,23 @@ proc checkDependencies*(
       let channel = rm.channels[channelId]
       for dep in deps:
         if dep.messageId notin channel.messageHistory:
-          missingDeps.add(dep)
+          # If we have a retrieval hint provider and the original dep has no hint, get one
+          if not rm.onRetrievalHint.isNil() and dep.retrievalHint.len == 0:
+            let hint = rm.onRetrievalHint(dep.messageId)
+            missingDeps.add(newHistoryEntry(dep.messageId, hint))
+          else:
+            missingDeps.add(dep)
     else:
-      missingDeps = deps
+      # Channel doesn't exist, all deps are missing
+      if not rm.onRetrievalHint.isNil():
+        for dep in deps:
+          if dep.retrievalHint.len == 0:
+            let hint = rm.onRetrievalHint(dep.messageId)
+            missingDeps.add(newHistoryEntry(dep.messageId, hint))
+          else:
+            missingDeps.add(dep)
+      else:
+        missingDeps = deps
   except Exception:
     error "Failed to check dependencies",
       channelId = channelId, error = getCurrentExceptionMsg()

tests/test_reliability.nim

@@ -99,7 +99,7 @@ suite "Reliability Mechanisms":
         messageReadyCount += 1,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         messageSentCount += 1,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         missingDepsCount += 1,
     )
 
@@ -176,7 +176,7 @@ suite "Reliability Mechanisms":
         messageReadyCount += 1,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         messageSentCount += 1,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         missingDepsCount += 1,
     )
 
@@ -216,7 +216,7 @@ suite "Reliability Mechanisms":
         discard,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         messageSentCount += 1,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         discard,
     )
 
@@ -261,7 +261,7 @@ suite "Reliability Mechanisms":
         messageReadyCount += 1,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         messageSentCount += 1,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         missingDepsCount += 1,
       nil,
       proc(messageId: SdsMessageID): seq[byte] =
@@ -301,8 +301,8 @@ suite "Reliability Mechanisms":
     let (_, missingDeps3, _) = unwrapResult3.get()
     check missingDeps3.len == 1
     check missingDeps3[0].messageId == "missing-dep"
-    # The hint is empty because it was not in our history, so the provider was not called
-    check missingDeps3[0].retrievalHint.len == 0
+    # The hint should be populated by the retrieval hint provider for missing dependencies
+    check missingDeps3[0].retrievalHint == cast[seq[byte]]("hint:missing-dep")
 
 # Periodic task & Buffer management tests
 suite "Periodic Tasks & Buffer Management":
@@ -326,7 +326,7 @@ suite "Periodic Tasks & Buffer Management":
         discard,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         messageSentCount += 1,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         discard,
     )
 
@@ -381,7 +381,7 @@ suite "Periodic Tasks & Buffer Management":
         discard,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         messageSentCount += 1,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         discard,
     )
 
@@ -430,7 +430,7 @@ suite "Periodic Tasks & Buffer Management":
         discard,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         discard,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         discard,
       proc() {.gcsafe.} =
         syncCallCount += 1,
@@ -496,7 +496,7 @@ suite "Special Cases Handling":
         messageReadyCount += 1,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         discard,
-      proc(messageId: SdsMessageID, missingDeps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, missingDeps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         discard,
     )
 
@@ -654,7 +654,7 @@ suite "Multi-Channel ReliabilityManager Tests":
         readyMessageCount += 1,
       proc(messageId: SdsMessageID, channelId: SdsChannelID) {.gcsafe.} =
         sentMessageCount += 1,
-      proc(messageId: SdsMessageID, deps: seq[SdsMessageID], channelId: SdsChannelID) {.gcsafe.} =
+      proc(messageId: SdsMessageID, deps: seq[HistoryEntry], channelId: SdsChannelID) {.gcsafe.} =
         missingDepsCount += 1
     )