93 lines
2.6 KiB
Nim
93 lines
2.6 KiB
Nim
## Nim-LibP2P
|
|
## Copyright (c) 2018 Status Research & Development GmbH
|
|
## Licensed under either of
|
|
## * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
|
|
## * MIT license ([LICENSE-MIT](LICENSE-MIT))
|
|
## at your option.
|
|
## This file may not be copied, modified, or distributed except according to
|
|
## those terms.
|
|
|
|
import sequtils, strutils
|
|
import chronos
|
|
import connection, varint, vbuffer
|
|
|
|
const MsgSize* = 64*1024
|
|
const Codec* = "/multistream/1.0.0"
|
|
const MultiCodec* = "\x19" & Codec & "\n"
|
|
const Na = "\x3na\n"
|
|
const Ls = "\x3ls\n"
|
|
|
|
type
|
|
MultisteamSelectException = object of CatchableError
|
|
|
|
Handler* = proc (conn: Connection, proto: string): Future[void]
|
|
Matcher* = proc (proto: string): bool
|
|
|
|
HandlerHolder* = object
|
|
proto: string
|
|
handler: Handler
|
|
match: Matcher
|
|
|
|
MultisteamSelect* = ref object of RootObj
|
|
handlers*: seq[HandlerHolder]
|
|
codec*: string
|
|
na*: string
|
|
ls*: string
|
|
|
|
proc newMultistream*(): MultisteamSelect =
|
|
new result
|
|
result.codec = MultiCodec
|
|
result.ls = Ls
|
|
result.na = Na
|
|
|
|
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())
|
|
ms.removeSuffix("\n")
|
|
if ms != Codec:
|
|
raise newException(MultisteamSelectException,
|
|
"Error: invalid multistream codec " & "\"" & ms & "\"")
|
|
|
|
if proto.len() <= 0:
|
|
return true
|
|
|
|
ms = cast[string](await conn.readLp())
|
|
ms.removeSuffix("\n")
|
|
result = ms == proto
|
|
|
|
proc handle*(m: MultisteamSelect, conn: Connection) {.async.} =
|
|
## handle requests on connection
|
|
if not (await m.select(conn)):
|
|
return
|
|
|
|
while not conn.closed:
|
|
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 & "\n")
|
|
else:
|
|
for h in m.handlers:
|
|
if (not isNil(h.match) and h.match(ms)) or ms == h.proto:
|
|
await h.handler(conn, ms)
|
|
return
|
|
else:
|
|
await conn.write(Na)
|
|
|
|
proc addHandler*(m: MultisteamSelect,
|
|
proto: string,
|
|
handler: Handler,
|
|
matcher: Matcher = nil) =
|
|
## register a handler for the protocol
|
|
m.handlers.add(HandlerHolder(proto: proto,
|
|
handler: handler,
|
|
match: matcher))
|