chore: specify raised exceptions in miscellaneous places (#1269)

Author: vladopajic

libp2p/connmanager.nim

@@ -276,7 +276,7 @@ proc selectMuxer*(c: ConnManager, peerId: PeerId): Muxer =
     trace "connection not found", peerId
   return mux
 
-proc storeMuxer*(c: ConnManager, muxer: Muxer) {.raises: [CatchableError].} =
+proc storeMuxer*(c: ConnManager, muxer: Muxer) {.raises: [LPError].} =
   ## store the connection and muxer
   ##
 

libp2p/daemon/daemonapi.nim

@@ -972,6 +972,7 @@ proc openStream*(
     raise newException(DaemonLocalError, "Wrong message type!")
 
 proc streamHandler(server: StreamServer, transp: StreamTransport) {.async.} =
+  # must not specify raised exceptions as this is StreamCallback from chronos
   var api = getUserData[DaemonAPI](server)
   var message = await transp.recvMessage()
   var pb = initProtoBuffer(message)

libp2p/discovery/discoverymngr.nim

@@ -79,16 +79,20 @@ type
     advertisementUpdated*: AsyncEvent
     advertiseLoop*: Future[void]
 
-method request*(self: DiscoveryInterface, pa: PeerAttributes) {.async, base.} =
+  DiscoveryError* = object of LPError
+  DiscoveryFinished* = object of LPError
+
+method request*(
+    self: DiscoveryInterface, pa: PeerAttributes
+) {.base, async: (raises: [DiscoveryError, CancelledError]).} =
   doAssert(false, "Not implemented!")
 
-method advertise*(self: DiscoveryInterface) {.async, base.} =
+method advertise*(
+    self: DiscoveryInterface
+) {.base, async: (raises: [CancelledError]).} =
   doAssert(false, "Not implemented!")
 
 type
-  DiscoveryError* = object of LPError
-  DiscoveryFinished* = object of LPError
-
   DiscoveryQuery* = ref object
     attr: PeerAttributes
     peers: AsyncQueue[PeerAttributes]
@@ -137,7 +141,9 @@ template forEach*(query: DiscoveryQuery, code: untyped) =
   ## peer attritubtes are available through the variable
   ## `peer`
 
-  proc forEachInternal(q: DiscoveryQuery) {.async.} =
+  proc forEachInternal(
+      q: DiscoveryQuery
+  ) {.async: (raises: [CancelledError, DiscoveryError]).} =
     while true:
       let peer {.inject.} =
         try:
@@ -162,7 +168,11 @@ proc stop*(dm: DiscoveryManager) =
       continue
     i.advertiseLoop.cancel()
 
-proc getPeer*(query: DiscoveryQuery): Future[PeerAttributes] {.async.} =
+proc getPeer*(
+    query: DiscoveryQuery
+): Future[PeerAttributes] {.
+    async: (raises: [CancelledError, DiscoveryError, DiscoveryFinished])
+.} =
   let getter = query.peers.popFirst()
 
   try:

libp2p/discovery/rendezvousinterface.nim

@@ -23,7 +23,9 @@ type
 
 proc `==`*(a, b: RdvNamespace): bool {.borrow.}
 
-method request*(self: RendezVousInterface, pa: PeerAttributes) {.async.} =
+method request*(
+    self: RendezVousInterface, pa: PeerAttributes
+) {.async: (raises: [DiscoveryError, CancelledError]).} =
   var namespace = ""
   for attr in pa:
     if attr.ofType(RdvNamespace):
@@ -48,7 +50,7 @@ method request*(self: RendezVousInterface, pa: PeerAttributes) {.async.} =
 
     await sleepAsync(self.timeToRequest)
 
-method advertise*(self: RendezVousInterface) {.async.} =
+method advertise*(self: RendezVousInterface) {.async: (raises: [CancelledError]).} =
   while true:
     var toAdvertise: seq[string]
     for attr in self.toAdvertise:

libp2p/peerstore.nim

@@ -188,7 +188,16 @@ proc cleanup*(peerStore: PeerStore, peerId: PeerId) =
     peerStore.del(peerStore.toClean[0])
     peerStore.toClean.delete(0)
 
-proc identify*(peerStore: PeerStore, muxer: Muxer) {.async.} =
+proc identify*(
+    peerStore: PeerStore, muxer: Muxer
+) {.
+    async: (
+      raises: [
+        CancelledError, IdentityNoMatchError, IdentityInvalidMsgError, MultiStreamError,
+        LPStreamError, MuxerError,
+      ]
+    )
+.} =
   # new stream for identify
   var stream = await muxer.newStream()
   if stream == nil:

libp2p/protocols/connectivity/relay/client.nim

@@ -80,7 +80,7 @@ proc handleRelayedConnect(
 
 proc reserve*(
     cl: RelayClient, peerId: PeerId, addrs: seq[MultiAddress] = @[]
-): Future[Rsvp] {.async.} =
+): Future[Rsvp] {.async: (raises: [ReservationError, DialFailedError, CancelledError]).} =
   let conn = await cl.switch.dial(peerId, addrs, RelayV2HopCodec)
   defer:
     await conn.close()

libp2p/protocols/rendezvous.nim

@@ -20,7 +20,8 @@ import
   ../utils/heartbeat,
   ../stream/connection,
   ../utils/offsettedseq,
-  ../utils/semaphore
+  ../utils/semaphore,
+  ../discovery/discoverymngr
 
 export chronicles
 
@@ -295,7 +296,7 @@ proc decode(_: typedesc[Message], buf: seq[byte]): Opt[Message] =
   Opt.some(msg)
 
 type
-  RendezVousError* = object of LPError
+  RendezVousError* = object of DiscoveryError
   RegisteredData = object
     expiration: Moment
     peerId: PeerId
@@ -555,7 +556,7 @@ proc requestLocally*(rdv: RendezVous, ns: string): seq[PeerRecord] =
 
 proc request*(
     rdv: RendezVous, ns: string, l: int = DiscoverLimit.int, peers: seq[PeerId]
-): Future[seq[PeerRecord]] {.async.} =
+): Future[seq[PeerRecord]] {.async: (raises: [DiscoveryError, CancelledError]).} =
   var
     s: Table[PeerId, (PeerRecord, Register)]
     limit: uint64
@@ -634,7 +635,7 @@ proc request*(
 
 proc request*(
     rdv: RendezVous, ns: string, l: int = DiscoverLimit.int
-): Future[seq[PeerRecord]] {.async.} =
+): Future[seq[PeerRecord]] {.async: (raises: [DiscoveryError, CancelledError]).} =
   await rdv.request(ns, l, rdv.peers)
 
 proc unsubscribeLocally*(rdv: RendezVous, ns: string) =

libp2p/services/autorelayservice.nim

@@ -41,7 +41,9 @@ proc addressMapper(
 
 proc reserveAndUpdate(
     self: AutoRelayService, relayPid: PeerId, switch: Switch
-) {.async.} =
+) {.async: (raises: [CatchableError]).} =
+  # CatchableError used to simplify raised errors here, as there could be 
+  # many different errors raised but caller don't really care what is cause of error
   while self.running:
     let
       rsvp = await self.client.reserve(relayPid).wait(chronos.seconds(5))
@@ -86,7 +88,9 @@ method setup*(
     await self.run(switch)
   return hasBeenSetUp
 
-proc manageBackedOff(self: AutoRelayService, pid: PeerId) {.async.} =
+proc manageBackedOff(
+    self: AutoRelayService, pid: PeerId
+) {.async: (raises: [CancelledError]).} =
   await sleepAsync(chronos.seconds(5))
   self.backingOff.keepItIf(it != pid)
   self.peerAvailable.fire()

libp2p/switch.nim

@@ -27,6 +27,7 @@ import
   protocols/secure/secure,
   peerinfo,
   utils/semaphore,
+  ./muxers/muxer,
   connmanager,
   nameresolving/nameresolver,
   peerid,
@@ -61,6 +62,8 @@ type
     started: bool
     services*: seq[Service]
 
+  UpgradeError* = object of LPError
+
   Service* = ref object of RootObj
     inUse: bool
 
@@ -216,30 +219,44 @@ proc mount*[T: LPProtocol](
   s.ms.addHandler(proto.codecs, proto, matcher)
   s.peerInfo.protocols.add(proto.codec)
 
-proc upgrader(switch: Switch, trans: Transport, conn: Connection) {.async.} =
-  let muxed = await trans.upgrade(conn, Opt.none(PeerId))
-  switch.connManager.storeMuxer(muxed)
-  await switch.peerStore.identify(muxed)
-  await switch.connManager.triggerPeerEvents(
-    muxed.connection.peerId, PeerEvent(kind: PeerEventKind.Identified, initiator: false)
-  )
-  trace "Connection upgrade succeeded"
+proc upgrader(
+    switch: Switch, trans: Transport, conn: Connection
+) {.async: (raises: [CancelledError, UpgradeError]).} =
+  try:
+    let muxed = await trans.upgrade(conn, Opt.none(PeerId))
+    switch.connManager.storeMuxer(muxed)
+    await switch.peerStore.identify(muxed)
+    await switch.connManager.triggerPeerEvents(
+      muxed.connection.peerId,
+      PeerEvent(kind: PeerEventKind.Identified, initiator: false),
+    )
+  except CancelledError as e:
+    raise e
+  except CatchableError as e:
+    raise newException(UpgradeError, e.msg, e)
 
 proc upgradeMonitor(
     switch: Switch, trans: Transport, conn: Connection, upgrades: AsyncSemaphore
-) {.async.} =
+) {.async: (raises: []).} =
+  var upgradeSuccessful = false
   try:
     await switch.upgrader(trans, conn).wait(30.seconds)
-  except CatchableError as exc:
-    if exc isnot CancelledError:
-      libp2p_failed_upgrades_incoming.inc()
-    if not isNil(conn):
-      await conn.close()
-    trace "Exception awaiting connection upgrade", description = exc.msg, conn
+    trace "Connection upgrade succeeded"
+    upgradeSuccessful = true
+  except CancelledError:
+    trace "Connection upgrade cancelled", conn
+  except AsyncTimeoutError:
+    trace "Connection upgrade timeout", conn
+    libp2p_failed_upgrades_incoming.inc()
+  except UpgradeError as e:
+    trace "Connection upgrade failed", description = e.msg, conn
+    libp2p_failed_upgrades_incoming.inc()
   finally:
+    if (not upgradeSuccessful) and (not isNil(conn)):
+      await conn.close()
     upgrades.release()
 
-proc accept(s: Switch, transport: Transport) {.async.} = # noraises
+proc accept(s: Switch, transport: Transport) {.async: (raises: []).} =
   ## switch accept loop, ran for every transport
   ##
 
@@ -286,7 +303,7 @@ proc accept(s: Switch, transport: Transport) {.async.} = # noraises
         await conn.close()
       return
 
-proc stop*(s: Switch) {.async, public.} =
+proc stop*(s: Switch) {.public, async: (raises: [CancelledError]).} =
   ## Stop listening on every transport, and
   ## close every active connections
 
@@ -318,7 +335,7 @@ proc stop*(s: Switch) {.async, public.} =
 
   trace "Switch stopped"
 
-proc start*(s: Switch) {.async, public.} =
+proc start*(s: Switch) {.public, async: (raises: [CancelledError, LPError]).} =
   ## Start listening on every transport
 
   if s.started:
@@ -340,7 +357,7 @@ proc start*(s: Switch) {.async, public.} =
   for fut in startFuts:
     if fut.failed:
       await s.stop()
-      raise fut.error
+      raise newException(LPError, "starting transports failed", fut.error)
 
   for t in s.transports: # for each transport
     if t.addrs.len > 0 or t.running: