feat: use json serde library for config over ffi

library/waku_thread_requests/requests/node_lifecycle_request.nim

@@ -1,5 +1,5 @@
 import std/[options, json, strutils, net]
-import chronos, chronicles, results, confutils, confutils/std/net
+import chronos, chronicles, results, confutils, confutils/std/net, json_serialization
 
 import
   ../../../waku/node/peer_manager/peer_manager,
@@ -40,41 +40,17 @@ proc destroyShared(self: ptr NodeLifecycleRequest) =
 proc createWaku(
     configJson: cstring, appCallbacks: AppCallbacks = nil
 ): Future[Result[Waku, string]] {.async.} =
-  var conf = defaultWakuNodeConf().valueOr:
-    return err("Failed creating node: " & error)
+  let decodedConf = Json.decode(configJson, WakuNodeConf)
 
   var errorResp: string
 
-  var jsonNode: JsonNode
-  try:
-    jsonNode = parseJson($configJson)
-  except Exception:
-    return err(
-      "exception in createWaku when calling parseJson: " & getCurrentExceptionMsg() &
-        " configJson string: " & $configJson
-    )
-
-  for confField, confValue in fieldPairs(conf):
-    if jsonNode.contains(confField):
-      # Make sure string doesn't contain the leading or trailing " character
-      let formattedString = ($jsonNode[confField]).strip(chars = {'\"'})
-      # Override conf field with the value set in the json-string
-      try:
-        confValue = parseCmdArg(typeof(confValue), formattedString)
-      except Exception:
-        return err(
-          "exception in createWaku when parsing configuration. exc: " &
-            getCurrentExceptionMsg() & ". string that could not be parsed: " &
-            formattedString & ". expected type: " & $typeof(confValue)
-        )
-
   # Don't send relay app callbacks if relay is disabled
-  if not conf.relay and not appCallbacks.isNil():
+  if not decodedConf.relay and not appCallbacks.isNil():
     appCallbacks.relayHandler = nil
     appCallbacks.topicHealthChangeHandler = nil
 
   # TODO: Convert `confJson` directly to `WakuConf`
-  var wakuConf = conf.toWakuConf().valueOr:
+  var wakuConf = decodedConf.toWakuConf().valueOr:
     return err("Configuration error: " & $error)
 
   wakuConf.restServerConf = none(RestServerConf) ## don't want REST in libwaku

waku.nimble

@@ -15,6 +15,7 @@ requires "nim >= 2.2.4",
   "chronos",
   "eth",
   "json_rpc",
+  "json_serialization",
   "libbacktrace",
   "nimcrypto",
   "stew",