refactor: simplify app.nim and move discovery items to appropriate mo…

…dules (#2657)

waku/discovery/waku_discv5.nim

@@ -14,7 +14,11 @@ import
   eth/keys as eth_keys,
   eth/p2p/discoveryv5/node,
   eth/p2p/discoveryv5/protocol
-import ../node/peer_manager/peer_manager, ../waku_core, ../waku_enr
+import
+  ../node/peer_manager/peer_manager,
+  ../waku_core,
+  ../waku_enr,
+  ../factory/external_config
 
 export protocol, waku_enr
 
@@ -244,7 +248,7 @@ proc subscriptionsListener(wd: WakuDiscoveryV5) {.async.} =
 
   wd.topicSubscriptionQueue.unregister(key)
 
-proc start*(wd: WakuDiscoveryV5): Future[Result[void, string]] {.async.} =
+proc start*(wd: WakuDiscoveryV5): Future[Result[void, string]] {.async: (raises: []).} =
   if wd.listening:
     return err("already listening")
 
@@ -313,3 +317,42 @@ proc addBootstrapNode*(bootstrapAddr: string, bootstrapEnrs: var seq[enr.Record]
     return
 
   bootstrapEnrs.add(enrRes.value)
+
+proc setupDiscoveryV5*(
+    myENR: enr.Record,
+    nodePeerManager: PeerManager,
+    nodeTopicSubscriptionQueue: AsyncEventQueue[SubscriptionEvent],
+    conf: WakuNodeConf,
+    dynamicBootstrapNodes: seq[RemotePeerInfo],
+    rng: ref HmacDrbgContext,
+    key: crypto.PrivateKey,
+): WakuDiscoveryV5 =
+  let dynamicBootstrapEnrs =
+    dynamicBootstrapNodes.filterIt(it.hasUdpPort()).mapIt(it.enr.get())
+
+  var discv5BootstrapEnrs: seq[enr.Record]
+
+  # parse enrURIs from the configuration and add the resulting ENRs to the discv5BootstrapEnrs seq
+  for enrUri in conf.discv5BootstrapNodes:
+    addBootstrapNode(enrUri, discv5BootstrapEnrs)
+
+  discv5BootstrapEnrs.add(dynamicBootstrapEnrs)
+
+  let discv5Config = DiscoveryConfig.init(
+    conf.discv5TableIpLimit, conf.discv5BucketIpLimit, conf.discv5BitsPerHop
+  )
+
+  let discv5UdpPort = Port(uint16(conf.discv5UdpPort) + conf.portsShift)
+
+  let discv5Conf = WakuDiscoveryV5Config(
+    discv5Config: some(discv5Config),
+    address: conf.listenAddress,
+    port: discv5UdpPort,
+    privateKey: eth_keys.PrivateKey(key.skkey),
+    bootstrapRecords: discv5BootstrapEnrs,
+    autoupdateRecord: conf.discv5EnrAutoUpdate,
+  )
+
+  WakuDiscoveryV5.new(
+    rng, discv5Conf, some(myENR), some(nodePeerManager), nodeTopicSubscriptionQueue
+  )

waku/discovery/waku_dnsdisc.nim

@@ -21,6 +21,7 @@ import
   libp2p/multiaddress,
   libp2p/peerid,
   dnsdisc/client
+import libp2p/nameresolving/dnsresolver
 import ../waku_core
 
 export client
@@ -97,3 +98,35 @@ proc init*(
   debug "init success"
 
   return ok(wakuDnsDisc)
+
+proc retrieveDynamicBootstrapNodes*(
+    dnsDiscovery: bool, dnsDiscoveryUrl: string, dnsDiscoveryNameServers: seq[IpAddress]
+): Result[seq[RemotePeerInfo], string] =
+  ## Retrieve dynamic bootstrap nodes (DNS discovery)
+
+  if dnsDiscovery and dnsDiscoveryUrl != "":
+    # DNS discovery
+    debug "Discovering nodes using Waku DNS discovery", url = dnsDiscoveryUrl
+
+    var nameServers: seq[TransportAddress]
+    for ip in dnsDiscoveryNameServers:
+      nameServers.add(initTAddress(ip, Port(53))) # Assume all servers use port 53
+
+    let dnsResolver = DnsResolver.new(nameServers)
+
+    proc resolver(domain: string): Future[string] {.async, gcsafe.} =
+      trace "resolving", domain = domain
+      let resolved = await dnsResolver.resolveTxt(domain)
+      return resolved[0] # Use only first answer
+
+    var wakuDnsDiscovery = WakuDnsDiscovery.init(dnsDiscoveryUrl, resolver)
+    if wakuDnsDiscovery.isOk():
+      return wakuDnsDiscovery.get().findPeers().mapErr(
+          proc(e: cstring): string =
+            $e
+        )
+    else:
+      warn "Failed to init Waku DNS discovery"
+
+  debug "No method for retrieving dynamic bootstrap nodes specified."
+  ok(newSeq[RemotePeerInfo]()) # Return an empty seq by default

waku/factory/app.nim

@@ -11,7 +11,6 @@ import
   libp2p/wire,
   libp2p/multicodec,
   libp2p/crypto/crypto,
-  libp2p/nameresolving/dnsresolver,
   libp2p/protocols/pubsub/gossipsub,
   libp2p/peerid,
   eth/keys,
@@ -59,7 +58,7 @@ type
     rng: ref HmacDrbgContext
     key: crypto.PrivateKey
 
-    wakuDiscv5*: Option[WakuDiscoveryV5]
+    wakuDiscv5*: WakuDiscoveryV5
     dynamicBootstrapNodes: seq[RemotePeerInfo]
 
     node: WakuNode
@@ -75,38 +74,6 @@ func node*(app: App): WakuNode =
 func version*(app: App): string =
   app.version
 
-## Retrieve dynamic bootstrap nodes (DNS discovery)
-
-proc retrieveDynamicBootstrapNodes*(
-    dnsDiscovery: bool, dnsDiscoveryUrl: string, dnsDiscoveryNameServers: seq[IpAddress]
-): Result[seq[RemotePeerInfo], string] =
-  if dnsDiscovery and dnsDiscoveryUrl != "":
-    # DNS discovery
-    debug "Discovering nodes using Waku DNS discovery", url = dnsDiscoveryUrl
-
-    var nameServers: seq[TransportAddress]
-    for ip in dnsDiscoveryNameServers:
-      nameServers.add(initTAddress(ip, Port(53))) # Assume all servers use port 53
-
-    let dnsResolver = DnsResolver.new(nameServers)
-
-    proc resolver(domain: string): Future[string] {.async, gcsafe.} =
-      trace "resolving", domain = domain
-      let resolved = await dnsResolver.resolveTxt(domain)
-      return resolved[0] # Use only first answer
-
-    var wakuDnsDiscovery = WakuDnsDiscovery.init(dnsDiscoveryUrl, resolver)
-    if wakuDnsDiscovery.isOk():
-      return wakuDnsDiscovery.get().findPeers().mapErr(
-          proc(e: cstring): string =
-            $e
-        )
-    else:
-      warn "Failed to init Waku DNS discovery"
-
-  debug "No method for retrieving dynamic bootstrap nodes specified."
-  ok(newSeq[RemotePeerInfo]()) # Return an empty seq by default
-
 ## Initialisation
 
 proc init*(T: type App, conf: WakuNodeConf): Result[App, string] =
@@ -121,7 +88,7 @@ proc init*(T: type App, conf: WakuNodeConf): Result[App, string] =
     confCopy.nodekey = some(keyRes.get())
 
   debug "Retrieve dynamic bootstrap nodes"
-  let dynamicBootstrapNodesRes = retrieveDynamicBootstrapNodes(
+  let dynamicBootstrapNodesRes = waku_dnsdisc.retrieveDynamicBootstrapNodes(
     confCopy.dnsDiscovery, confCopy.dnsDiscoveryUrl, confCopy.dnsDiscoveryNameServers
   )
   if dynamicBootstrapNodesRes.isErr():
@@ -147,43 +114,6 @@ proc init*(T: type App, conf: WakuNodeConf): Result[App, string] =
 
   ok(app)
 
-## Setup DiscoveryV5
-
-proc setupDiscoveryV5*(app: App): WakuDiscoveryV5 =
-  let dynamicBootstrapEnrs =
-    app.dynamicBootstrapNodes.filterIt(it.hasUdpPort()).mapIt(it.enr.get())
-
-  var discv5BootstrapEnrs: seq[enr.Record]
-
-  # parse enrURIs from the configuration and add the resulting ENRs to the discv5BootstrapEnrs seq
-  for enrUri in app.conf.discv5BootstrapNodes:
-    addBootstrapNode(enrUri, discv5BootstrapEnrs)
-
-  discv5BootstrapEnrs.add(dynamicBootstrapEnrs)
-
-  let discv5Config = DiscoveryConfig.init(
-    app.conf.discv5TableIpLimit, app.conf.discv5BucketIpLimit, app.conf.discv5BitsPerHop
-  )
-
-  let discv5UdpPort = Port(uint16(app.conf.discv5UdpPort) + app.conf.portsShift)
-
-  let discv5Conf = WakuDiscoveryV5Config(
-    discv5Config: some(discv5Config),
-    address: app.conf.listenAddress,
-    port: discv5UdpPort,
-    privateKey: keys.PrivateKey(app.key.skkey),
-    bootstrapRecords: discv5BootstrapEnrs,
-    autoupdateRecord: app.conf.discv5EnrAutoUpdate,
-  )
-
-  WakuDiscoveryV5.new(
-    app.rng,
-    discv5Conf,
-    some(app.node.enr),
-    some(app.node.peerManager),
-    app.node.topicSubscriptionQueue,
-  )
-
 proc getPorts(
     listenAddrs: seq[MultiAddress]
 ): AppResult[tuple[tcpPort, websocketPort: Option[Port]]] =
@@ -259,17 +189,13 @@ proc startApp*(app: var App): AppResult[void] =
 
   ## Discv5
   if app.conf.discv5Discovery:
-    app.wakuDiscV5 = some(app.setupDiscoveryV5())
-
-  if app.wakuDiscv5.isSome():
-    let wakuDiscv5 = app.wakuDiscv5.get()
-    let catchRes = catch:
-      (waitFor wakuDiscv5.start())
-    let startRes = catchRes.valueOr:
-      return err("failed to start waku discovery v5: " & catchRes.error.msg)
+    app.wakuDiscV5 = waku_discv5.setupDiscoveryV5(
+      app.node.enr, app.node.peerManager, app.node.topicSubscriptionQueue, app.conf,
+      app.dynamicBootstrapNodes, app.rng, app.key,
+    )
 
-    startRes.isOkOr:
-      return err("failed to start waku discovery v5: " & error)
+    (waitFor app.wakuDiscV5.start()).isOkOr:
+      return err("failed to start waku discovery v5: " & $error)
 
   return ok()
 
@@ -282,8 +208,8 @@ proc stop*(app: App): Future[void] {.async: (raises: [Exception]).} =
   if not app.metricsServer.isNil():
     await app.metricsServer.stop()
 
-  if app.wakuDiscv5.isSome():
-    await app.wakuDiscv5.get().stop()
+  if not app.wakuDiscv5.isNil():
+    await app.wakuDiscv5.stop()
 
   if not app.node.isNil():
     await app.node.stop()

waku/node/waku_node.nim

@@ -50,7 +50,6 @@ import
   ../waku_rln_relay,
   ./config,
   ./peer_manager,
-  ../discovery/waku_dnsdisc,
   ../common/ratelimit
 
 declarePublicCounter waku_node_messages, "number of messages received", ["type"]

waku/waku_api/rest/builder.nim

@@ -113,7 +113,7 @@ proc startRestServerEsentials*(
 proc startRestServerProtocolSupport*(
     restServer: WakuRestServerRef,
     node: WakuNode,
-    wakuDiscv5: Option[WakuDiscoveryV5],
+    wakuDiscv5: WakuDiscoveryV5,
     conf: WakuNodeConf,
 ): Result[void, string] =
   if not conf.rest:
@@ -154,8 +154,8 @@ proc startRestServerProtocolSupport*(
     let filterCache = MessageCache.init()
 
     let filterDiscoHandler =
-      if wakuDiscv5.isSome():
-        some(defaultDiscoveryHandler(wakuDiscv5.get(), Filter))
+      if not wakuDiscv5.isNil():
+        some(defaultDiscoveryHandler(wakuDiscv5, Filter))
       else:
         none(DiscoveryHandler)
 
@@ -168,8 +168,8 @@ proc startRestServerProtocolSupport*(
 
   ## Store REST API
   let storeDiscoHandler =
-    if wakuDiscv5.isSome():
-      some(defaultDiscoveryHandler(wakuDiscv5.get(), Store))
+    if not wakuDiscv5.isNil():
+      some(defaultDiscoveryHandler(wakuDiscv5, Store))
     else:
       none(DiscoveryHandler)
 
@@ -182,8 +182,8 @@ proc startRestServerProtocolSupport*(
   if (conf.lightpushnode != "" and node.wakuLightpushClient != nil) or
       (conf.lightpush and node.wakuLightPush != nil and node.wakuRelay != nil):
     let lightDiscoHandler =
-      if wakuDiscv5.isSome():
-        some(defaultDiscoveryHandler(wakuDiscv5.get(), Lightpush))
+      if not wakuDiscv5.isNil():
+        some(defaultDiscoveryHandler(wakuDiscv5, Lightpush))
       else:
         none(DiscoveryHandler)