Files
py-libp2p/tests/interop/nim_libp2p/nim_echo_server.nim
2025-08-30 14:08:53 +05:30

109 lines
2.6 KiB
Nim

{.used.}
import chronos
import stew/byteutils
import libp2p
##
# Simple Echo Protocol Implementation for py-libp2p Interop Testing
##
const EchoCodec = "/echo/1.0.0"
type EchoProto = ref object of LPProtocol
proc new(T: typedesc[EchoProto]): T =
proc handle(conn: Connection, proto: string) {.async: (raises: [CancelledError]).} =
try:
echo "Echo server: Received connection from ", conn.peerId
# Read and echo messages in a loop
while not conn.atEof:
try:
# Read length-prefixed message using nim-libp2p's readLp
let message = await conn.readLp(1024 * 1024) # Max 1MB
if message.len == 0:
echo "Echo server: Empty message, closing connection"
break
let messageStr = string.fromBytes(message)
echo "Echo server: Received (", message.len, " bytes): ", messageStr
# Echo back using writeLp
await conn.writeLp(message)
echo "Echo server: Echoed message back"
except CatchableError as e:
echo "Echo server: Error processing message: ", e.msg
break
except CancelledError as e:
echo "Echo server: Connection cancelled"
raise e
except CatchableError as e:
echo "Echo server: Exception in handler: ", e.msg
finally:
echo "Echo server: Connection closed"
await conn.close()
return T.new(codecs = @[EchoCodec], handler = handle)
##
# Create QUIC-enabled switch
##
proc createSwitch(ma: MultiAddress, rng: ref HmacDrbgContext): Switch =
var switch = SwitchBuilder
.new()
.withRng(rng)
.withAddress(ma)
.withQuicTransport()
.build()
result = switch
##
# Main server
##
proc main() {.async.} =
let
rng = newRng()
localAddr = MultiAddress.init("/ip4/0.0.0.0/udp/0/quic-v1").tryGet()
echoProto = EchoProto.new()
echo "=== Nim Echo Server for py-libp2p Interop ==="
# Create switch
let switch = createSwitch(localAddr, rng)
switch.mount(echoProto)
# Start server
await switch.start()
# Print connection info
echo "Peer ID: ", $switch.peerInfo.peerId
echo "Listening on:"
for addr in switch.peerInfo.addrs:
echo " ", $addr, "/p2p/", $switch.peerInfo.peerId
echo "Protocol: ", EchoCodec
echo "Ready for py-libp2p connections!"
echo ""
# Keep running
try:
await sleepAsync(100.hours)
except CancelledError:
echo "Shutting down..."
finally:
await switch.stop()
# Graceful shutdown handler
proc signalHandler() {.noconv.} =
echo "\nShutdown signal received"
quit(0)
when isMainModule:
setControlCHook(signalHandler)
try:
waitFor(main())
except CatchableError as e:
echo "Error: ", e.msg
quit(1)