refactor(dht-proxy): unify ResponseStatus+ErrorKind into single LookupCode enum (#1473)

Signed-off-by: Chrysostomos Nanakos <chris@include.gr>

storage/dht_proxy/client.nim

@@ -29,8 +29,7 @@ logScope:
   topics = "storage dht-proxy client"
 
 type LookupResult = object
-  status: ResponseStatus
-  errorKind: ErrorKind
+  code: LookupCode
   providers: seq[SignedPeerRecord]
 
 proc requestLookup(
@@ -57,10 +56,7 @@ proc requestLookup(
         providers.add(res.get)
       else:
         warn "Failed to decode SignedPeerRecord from response", err = $res.error
-
-    return success LookupResult(
-      status: resp.status, errorKind: resp.errorKind, providers: providers
-    )
+    return success LookupResult(code: resp.code, providers: providers)
   except LPStreamError as exc:
     return failure("Stream error: " & exc.msg)
   except CatchableError as exc:
@@ -103,13 +99,14 @@ proc lookupProviders*(
       return failure(lookupRes.error)
     let lookup = lookupRes.get()
 
-    case lookup.status
-    of ResponseStatus.Ok:
+    case lookup.code
+    of LookupCode.Ok:
       return success lookup.providers
-    of ResponseStatus.NotFound:
+    of LookupCode.NotFound:
       return success newSeq[SignedPeerRecord]()
-    of ResponseStatus.Error:
-      return failure("Remote returned error: " & $lookup.errorKind)
+    of LookupCode.ErrDecodeFailed, LookupCode.ErrInvalidCid, LookupCode.ErrInternal,
+        LookupCode.ErrResponseTooLarge, LookupCode.ErrTooBusy:
+      return failure("Remote returned error: " & $lookup.code)
   except CancelledError as exc:
     raise exc
   except CatchableError as exc:

storage/dht_proxy/handler.nim

@@ -34,14 +34,13 @@ proc handleFindProviders(
   let
     cid = Cid.init(queryBytes).valueOr:
       warn "Invalid CID in lookup request"
-      return
-        LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.InvalidCid)
+      return LookupResponse(code: LookupCode.ErrInvalidCid)
     providers = (await self.discovery.findDirect(cid)).valueOr:
       warn "Direct lookup failed", cid, err = error.msg
-      return LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.Internal)
+      return LookupResponse(code: LookupCode.ErrInternal)
 
   if providers.len == 0:
-    return LookupResponse(status: ResponseStatus.NotFound)
+    return LookupResponse(code: LookupCode.NotFound)
 
   var encoded = newSeqOfCap[seq[byte]](providers.len)
   for spr in providers:
@@ -51,23 +50,21 @@ proc handleFindProviders(
     encoded.add(bytes)
 
   if encoded.len == 0:
-    return LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.Internal)
+    return LookupResponse(code: LookupCode.ErrInternal)
 
   let packed = packProviders(encoded, MaxLookupResponseBytes).valueOr:
-    return LookupResponse(status: ResponseStatus.Error, errorKind: error)
+    return LookupResponse(code: error)
 
-  LookupResponse(status: ResponseStatus.Ok, providers: packed)
+  LookupResponse(code: LookupCode.Ok, providers: packed)
 
 proc handleLookupRequest(
     self: DhtProxyProtocol, conn: Connection
 ) {.async: (raises: [CancelledError]).} =
   try:
     if self.inFlight >= self.maxInFlight:
-      debug "DHT proxy at capacity, replying TooBusy",
+      debug "DHT proxy at capacity, replying ErrTooBusy",
         inFlight = self.inFlight, max = self.maxInFlight
-      await conn.writeLp(
-        LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.TooBusy).encode()
-      )
+      await conn.writeLp(LookupResponse(code: LookupCode.ErrTooBusy).encode())
       return
 
     inc self.inFlight
@@ -78,11 +75,7 @@ proc handleLookupRequest(
       reqBytes = await conn.readLp(MaxLookupRequestBytes)
       req = LookupRequest.decode(reqBytes).valueOr:
         warn "Failed to decode lookup request"
-        await conn.writeLp(
-          LookupResponse(
-            status: ResponseStatus.Error, errorKind: ErrorKind.DecodeFailed
-          ).encode()
-        )
+        await conn.writeLp(LookupResponse(code: LookupCode.ErrDecodeFailed).encode())
         return
 
     let resp =

storage/dht_proxy/protocol.nim

@@ -12,6 +12,7 @@
 import pkg/libp2p/protobuf/minprotobuf
 import pkg/libp2p_mix
 import pkg/libp2p/routing_record
+import pkg/stew/objects
 
 import ../logutils
 
@@ -31,25 +32,21 @@ type
   QueryType* {.pure.} = enum
     FindProviders = 0
 
-  ResponseStatus* {.pure.} = enum
+  LookupCode* {.pure.} = enum
     Ok = 0
     NotFound = 1
-    Error = 2
-
-  ErrorKind* {.pure.} = enum
-    DecodeFailed = 0
-    InvalidCid = 1
-    Internal = 2
-    ResponseTooLarge = 3
-    TooBusy = 4
+    ErrDecodeFailed = 100
+    ErrInvalidCid = 101
+    ErrInternal = 200
+    ErrResponseTooLarge = 201
+    ErrTooBusy = 202
 
   LookupRequest* = object
     queryType*: QueryType
     queryBytes*: seq[byte]
 
   LookupResponse* = object
-    status*: ResponseStatus
-    errorKind*: ErrorKind
+    code*: LookupCode
     providers*: seq[seq[byte]]
 
 proc encode*(req: LookupRequest): seq[byte] =
@@ -61,11 +58,9 @@ proc encode*(req: LookupRequest): seq[byte] =
 
 proc encode*(resp: LookupResponse): seq[byte] =
   var pb = initProtoBuffer()
-  pb.write(1, resp.status.uint32)
-  if resp.status == ResponseStatus.Error:
-    pb.write(2, resp.errorKind.uint32)
+  pb.write(1, resp.code.uint32)
   for spr in resp.providers:
-    pb.write(3, spr)
+    pb.write(2, spr)
   pb.finish()
   pb.buffer
 
@@ -76,9 +71,8 @@ proc decode*(_: type LookupRequest, data: openArray[byte]): ProtoResult[LookupRe
     qt: uint32
 
   if ?pb.getField(1, qt):
-    if qt > QueryType.high.uint32:
+    if not checkedEnumAssign(req.queryType, qt):
       return err(ProtoError.IncorrectBlob)
-    req.queryType = QueryType(qt)
 
   discard ?pb.getField(2, req.queryBytes)
   ok(req)
@@ -89,34 +83,25 @@ proc decode*(
   let pb = initProtoBuffer(data)
   var
     resp = LookupResponse()
-    status: uint32
+    codeOrd: uint32
 
-  if ?pb.getField(1, status):
-    if status > ResponseStatus.high.uint32:
+  if ?pb.getField(1, codeOrd):
+    if not checkedEnumAssign(resp.code, codeOrd):
       return err(ProtoError.IncorrectBlob)
-    resp.status = ResponseStatus(status)
-
-  if resp.status == ResponseStatus.Error:
-    var ek: uint32
-    if ?pb.getField(2, ek):
-      if ek > ErrorKind.high.uint32:
-        return err(ProtoError.IncorrectBlob)
-      resp.errorKind = ErrorKind(ek)
-
-  discard ?pb.getRepeatedField(3, resp.providers)
 
+  discard ?pb.getRepeatedField(2, resp.providers)
   ok(resp)
 
 proc packProviders*(
     providers: seq[seq[byte]], budget_bytes: int
-): Result[seq[seq[byte]], ErrorKind] =
+): Result[seq[seq[byte]], LookupCode] =
   if providers.len == 0:
     error "packProviders called with no providers"
-    return err(ErrorKind.Internal)
+    return err(LookupCode.ErrInternal)
 
-  let single = LookupResponse(status: ResponseStatus.Ok, providers: providers[0 ..< 1])
+  let single = LookupResponse(code: LookupCode.Ok, providers: providers[0 ..< 1])
   if single.encode().len > budget_bytes:
-    return err(ErrorKind.ResponseTooLarge)
+    return err(LookupCode.ErrResponseTooLarge)
 
   var
     lo = 1
@@ -124,7 +109,7 @@ proc packProviders*(
   while lo < hi:
     let
       mid = (lo + hi + 1) div 2
-      test = LookupResponse(status: ResponseStatus.Ok, providers: providers[0 ..< mid])
+      test = LookupResponse(code: LookupCode.Ok, providers: providers[0 ..< mid])
     if test.encode().len <= budget_bytes:
       lo = mid
     else:

tools/mix/mix_relay_dht.nim

@@ -126,22 +126,21 @@ proc handleFindProviders(
 ): Future[LookupResponse] {.async: (raises: [CancelledError]).} =
   let c = Cid.init(queryBytes).valueOr:
     warn "Invalid CID in lookup request"
-    return LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.InvalidCid)
+    return LookupResponse(code: LookupCode.ErrInvalidCid)
 
   let providers =
     try:
       (await self.dht.getProviders(c.toNodeId())).valueOr:
         warn "discv5 getProviders failed", err = $error
-        return
-          LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.Internal)
+        return LookupResponse(code: LookupCode.ErrInternal)
     except CancelledError as exc:
       raise exc
     except CatchableError as exc:
       warn "discv5 getProviders raised", err = exc.msg
-      return LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.Internal)
+      return LookupResponse(code: LookupCode.ErrInternal)
 
   if providers.len == 0:
-    return LookupResponse(status: ResponseStatus.NotFound)
+    return LookupResponse(code: LookupCode.NotFound)
 
   var encoded = newSeqOfCap[seq[byte]](providers.len)
   for rec in providers:
@@ -151,23 +150,21 @@ proc handleFindProviders(
     encoded.add(bytes)
 
   if encoded.len == 0:
-    return LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.Internal)
+    return LookupResponse(code: LookupCode.ErrInternal)
 
   let packed = packProviders(encoded, MaxLookupResponseBytes).valueOr:
-    return LookupResponse(status: ResponseStatus.Error, errorKind: error)
+    return LookupResponse(code: error)
 
-  LookupResponse(status: ResponseStatus.Ok, providers: packed)
+  LookupResponse(code: LookupCode.Ok, providers: packed)
 
 proc handleLookupRequest(
     self: DhtProxyProtocol, conn: Connection
 ) {.async: (raises: [CancelledError]).} =
   try:
     if self.inFlight >= self.maxInFlight:
-      debug "DHT proxy at capacity, replying TooBusy",
+      debug "DHT proxy at capacity, replying ErrTooBusy",
         inFlight = self.inFlight, max = self.maxInFlight
-      await conn.writeLp(
-        LookupResponse(status: ResponseStatus.Error, errorKind: ErrorKind.TooBusy).encode()
-      )
+      await conn.writeLp(LookupResponse(code: LookupCode.ErrTooBusy).encode())
       return
 
     inc self.inFlight
@@ -178,11 +175,7 @@ proc handleLookupRequest(
       reqBytes = await conn.readLp(MaxLookupRequestBytes)
       req = LookupRequest.decode(reqBytes).valueOr:
         warn "Failed to decode lookup request"
-        await conn.writeLp(
-          LookupResponse(
-            status: ResponseStatus.Error, errorKind: ErrorKind.DecodeFailed
-          ).encode()
-        )
+        await conn.writeLp(LookupResponse(code: LookupCode.ErrDecodeFailed).encode())
         return
 
     let resp =