wip: initial multistream handler implementation

libp2p/multistreamselect.nim

@@ -13,9 +13,9 @@ import connection, varint, vbuffer
 
 const MsgSize* = 64*1024
 const Codec* = "/multistream/1.0.0"
-const MultiCodec* = Codec & "\n"
-const Na = "na\n"
-const Ls = "ls\n"
+const MultiCodec* = "\x19" & Codec & "\n"
+const Na = "\x3na\n"
+const Ls = "\x3ls\n"
 
 type 
   MultisteamSelectException = object of CatchableError
@@ -30,56 +30,59 @@ type
 
   MultisteamSelect* = ref object of RootObj
     handlers*: seq[HandlerHolder]
-    codec*: seq[byte]
-    na*: seq[byte]
-    ls*: seq[byte]
-
-proc lp*(data: string, s: var seq[byte]): int =
-  var buf = initVBuffer(s)
-  buf.writeSeq(data)
-  buf.finish()
-  s = buf.buffer
+    codec*: string
+    na*: string
+    ls*: string
 
 proc newMultistream*(): MultisteamSelect =
   new result
-  result.codec = newSeq[byte]()
-  discard lp(MultiCodec, result.codec)
+  result.codec = MultiCodec
+  result.ls = Ls
+  result.na = Na
 
-  result.na = newSeq[byte]()
-  discard lp(Na, result.na)
-
-  result.ls = newSeq[byte]()
-  discard lp(Ls, result.ls)
-
-proc select*(m: MultisteamSelect, conn: Connection, proto: string): Future[bool] {.async.} = 
+proc select*(m: MultisteamSelect, conn: Connection, proto: string = ""): Future[bool] {.async.} = 
   ## select a remote protocol
+  ## TODO: select should support a list of protos to be selected
+
   await conn.write(m.codec) # write handshake
   await conn.writeLp(proto) # select proto
   var ms = cast[string](await conn.readLp())
-  echo MultiCodec
-  if ms != MultiCodec:
+  ms.removeSuffix("\n")
+  if ms != Codec:
     raise newException(MultisteamSelectException, 
                        "Error: invalid multistream codec " & "\"" & ms & "\"")
 
-  var msProto = cast[string](await conn.readLp())
-  msProto.removeSuffix("\n")
-  result = msProto == proto
+  if proto.len() <= 0:
+    return true
 
-proc ls*(m: MultisteamSelect): Future[seq[string]] {.async.} = 
-  ## list all remote protocol strings
-  discard
+  ms = cast[string](await conn.readLp())
+  ms.removeSuffix("\n")
+  result = ms == proto
 
-# proc handle*(m: MultisteamSelect, conn: Connection) {.async.} =
-#   ## handle requests on connection
-#   await conn.write(m.codec)
+proc handle*(m: MultisteamSelect, conn: Connection) {.async.} =
+  ## handle requests on connection
+  if not (await m.select(conn)):
+    return
   
-#   let ms = await conn.readLine(0, "\n")
-#   if ms != MultiCodec:
-#     raise newException(MultisteamSelectException, 
-#                        "Error: invalid multistream codec " & "\"" & $ms & "\"")
-  
-#   let ms = await conn.readLine(0, "\n")
+  block handleLoop:
+    var ms = cast[string](await conn.readLp())
+    ms.removeSuffix("\n")
+    if ms.len() <= 0:
+      await conn.writeLp(Na)
 
+    case ms:
+      of "ls": 
+        for h in m.handlers:
+          await conn.writeLp(h.proto)
+          break handleLoop
+      else: 
+        for h in m.handlers:
+          if (not isNil(h.match) and h.match(ms)) or ms == h.proto:
+            await h.handler(conn, ms)
+            break
+          else:
+            await conn.write(Na)
+            break handleLoop
 
 proc addHandler*(m: MultisteamSelect, 
                  proto: string, 

tests/testmultistreamselect.nim

@@ -3,12 +3,12 @@ import chronos
 import ../libp2p/connection, ../libp2p/multistreamselect, 
   ../libp2p/readerwriter, ../libp2p/connection
 
-# custom select stream
+## Stream for select test
 type
-  TestStream = ref object of ReadWrite
+  TestSelectStream = ref object of ReadWrite
     step*: int
 
-method readExactly*(s: TestStream, pbytes: pointer, nbytes: int): Future[void] {.async.} =
+method readExactly*(s: TestSelectStream, pbytes: pointer, nbytes: int): Future[void] {.async.} =
   case s.step:
     of 1:
       var buf = newSeq[byte](1)
@@ -16,7 +16,7 @@ method readExactly*(s: TestStream, pbytes: pointer, nbytes: int): Future[void] {
       copyMem(cast[pointer](cast[uint](pbytes)), addr buf[0], buf.len())
       s.step = 2
     of 2:
-      var buf = MultiCodec
+      var buf = "/multistream/1.0.0\n"
       copyMem(cast[pointer](cast[uint](pbytes)), addr buf[0], buf.len())
       s.step = 3
     of 3:
@@ -30,30 +30,62 @@ method readExactly*(s: TestStream, pbytes: pointer, nbytes: int): Future[void] {
     else: 
       copyMem(cast[pointer](cast[uint](pbytes)), cstring("\0x3na\n"), "\0x3na\n".len())
 
-proc newTestStream(): TestStream =
+proc newTestSelectStream(): TestSelectStream =
+  new result
+  result.step = 1
+
+## Stream for handles test
+type
+  TestHandlesStream = ref object of ReadWrite
+    step*: int
+
+method readExactly*(s: TestHandlesStream, pbytes: pointer, nbytes: int): Future[void] {.async.} =
+  case s.step:
+    of 1:
+      var buf = newSeq[byte](1)
+      buf[0] = 19
+      copyMem(cast[pointer](cast[uint](pbytes)), addr buf[0], buf.len())
+      s.step = 2
+    of 2:
+      var buf = "/multistream/1.0.0\n"
+      copyMem(cast[pointer](cast[uint](pbytes)), addr buf[0], buf.len())
+      s.step = 3
+    of 3:
+      var buf = newSeq[byte](1)
+      buf[0] = 18
+      copyMem(cast[pointer](cast[uint](pbytes)), addr buf[0], buf.len())
+      s.step = 4
+    of 4:
+      var buf = "/test/proto/1.0.0\n"
+      copyMem(cast[pointer](cast[uint](pbytes)), addr buf[0], buf.len())
+    else: 
+      copyMem(cast[pointer](cast[uint](pbytes)), cstring("\0x3na\n"), "\0x3na\n".len())
+
+proc newTestHandlesStream(): TestHandlesStream =
   new result
   result.step = 1
 
 suite "Multistream select":
-  test "test select":
-    proc testSelect(): Future[bool] {.async.} =
-      let ms = newMultistream()
-      let conn = newConnection(newTestStream())
-      result = await ms.select(conn, "/test/proto/1.0.0")
-
-    check:
-      waitFor(testSelect()) == true
-  
-  # test "test handle":
-  #   proc testHandle(): Future[bool] {.async.} =
+  # test "test select custom proto":
+  #   proc testSelect(): Future[bool] {.async.} =
   #     let ms = newMultistream()
-  #     let conn = newConnection(newTestStream())
-
-  #     proc testHandler(conn: Connection, proto: string): Future[void] =
-  #       check proto == "/test/proto/1.0.0"
-
-  #     ms.addHandler("/test/proto/1.0.0", testHandler)
-  #     await ms.handle(conn)
+  #     let conn = newConnection(newTestSelectStream())
+  #     result = await ms.select(conn, "/test/proto/1.0.0")
 
   #   check:
-  #     waitFor(testHandle()) == true
+  #     waitFor(testSelect()) == true
+
+  test "test handle custom proto":
+    proc testHandle(): Future[bool] {.async.} =
+      let ms = newMultistream()
+      let conn = newConnection(newTestHandlesStream())
+
+      proc testHandler(conn: Connection, proto: string): Future[void] {.async.} =
+        check proto == "/test/proto/1.0.0"
+
+      ms.addHandler("/test/proto/1.0.0", testHandler)
+      await ms.handle(conn)
+      result = true
+
+    check:
+      waitFor(testHandle()) == true