nim-libp2p/libp2p/protocols/protocol.nim

## Nim-LibP2P
## Copyright (c) 2019 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.

{.push raises: [Defect].}

import chronos
import ../stream/connection

type
  LPProtoHandler* = proc (
    conn: Connection,
    proto: string):
    Future[void]
    {.gcsafe, raises: [Defect].}

  LPProtocol* = ref object of RootObj
    codecs*: seq[string]
    handler*: LPProtoHandler ## this handler gets invoked by the protocol negotiator

method init*(p: LPProtocol) {.base, gcsafe.} = discard

func codec*(p: LPProtocol): string =
  assert(p.codecs.len > 0, "Codecs sequence was empty!")
  p.codecs[0]

func `codec=`*(p: LPProtocol, codec: string) =
  # always insert as first codec
  # if we use this abstraction
  p.codecs.insert(codec, 0)