fix: fixes from Ivan's mix send PR review

logos_delivery/api/conf/modes.nim

@@ -18,6 +18,6 @@ type EntryLayer* {.pure.} = enum
   channels # kernel + messaging + reliable channels
 
 type AnonymityLevel* {.pure.} = enum
-  None
-  Preferred
-  Required
+  None ## Never use Mix. Send over the plain path, relay then lightpush.
+  Preferred ## Try Mix first. Use the plain path after the Mix window expires.
+  Required ## Use Mix only. Never use the plain path.

logos_delivery/messaging/delivery_service/send_service/mix_processor.nim

@@ -35,16 +35,15 @@ proc mixWindowElapsed(self: MixSendProcessor, task: DeliveryTask): bool =
 
 method sendImpl*(self: MixSendProcessor, task: DeliveryTask): Future[void] {.async.} =
   if self.mixWindowElapsed(task):
-    trace "Mix window elapsed, handing the task to the plain send path",
+    debug "Mix window elapsed",
       requestId = task.requestId,
       msgHash = task.msgHash.to0xHex(),
       admissionAge = task.admissionAge()
     task.state = DeliveryState.FallbackRetry
     return
 
   if not self.waku.mixReady():
-    trace "Mix cannot publish yet (not enough nodes for a path), retrying next round",
-      requestId = task.requestId, msgHash = task.msgHash.to0xHex()
+    debug "Mix not ready", requestId = task.requestId, msgHash = task.msgHash.to0xHex()
     task.state = DeliveryState.NextRoundRetry
     return
 

logos_delivery/messaging/delivery_service/send_service/send_service.nim

@@ -74,23 +74,22 @@ proc setupSendProcessorChain(
   let isRelayAvail = waku.hasRelay()
   let isLightPushAvail = waku.hasLightpush()
 
-  if anonymityLevel != AnonymityLevel.None and not isLightPushAvail:
-    return err("Mix sending needs a lightpush client, which is not mounted")
-
-  if anonymityLevel != AnonymityLevel.Required and not isRelayAvail and
-      not isLightPushAvail:
-    return err("No valid send processor found for the delivery task")
-
   var processors = newSeq[BaseSendProcessor]()
 
-  if anonymityLevel != AnonymityLevel.None:
+  case anonymityLevel
+  of AnonymityLevel.None:
+    discard
+  of AnonymityLevel.Preferred, AnonymityLevel.Required:
+    if not isLightPushAvail:
+      return err("Mix sending needs a lightpush client, which is not mounted")
+
     let mixProcessor: BaseSendProcessor =
       MixSendProcessor.new(waku, brokerCtx, anonymityLevel, MaxTimeInCache)
-    processors.add(mixProcessor)
-
     if anonymityLevel == AnonymityLevel.Required:
       return ok(mixProcessor)
 
+    processors.add(mixProcessor)
+
   if isRelayAvail:
     let publishProc = waku.relayPushHandler()
     processors.add(
@@ -99,6 +98,9 @@ proc setupSendProcessorChain(
   if isLightPushAvail:
     processors.add(LightpushSendProcessor.new(waku, brokerCtx))
 
+  if processors.len == 0:
+    return err("No valid send processor found for the delivery task")
+
   var currentProcessor: BaseSendProcessor = processors[0]
   for i in 1 ..< processors.len:
     currentProcessor.chain(processors[i])