mirror of https://github.com/vacp2p/nim-libp2p.git
Add examples to CI (#599)
* add examples to CI * add markdown runner * two tutorials
This commit is contained in:
parent
e1d96a0f4d
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e787fc35a6
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@ -1,98 +1,7 @@
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# Getting Started
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Welcome to nim-libp2p! This guide will walk you through a peer to peer chat example. <br>
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The full code can be found in [directchat.nim](examples/directchat.nim) under the examples folder.
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Welcome to nim-libp2p!
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### Direct Chat Example
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To run nim-libp2p, add it to your project's nimble file and spawn a node as follows:
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To get started, please look at the [tutorials](../examples/tutorial_1_connect.md)
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```nim
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import tables
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import chronos
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import ../libp2p/[switch,
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multistream,
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protocols/identify,
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connection,
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transports/transport,
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transports/tcptransport,
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multiaddress,
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peerinfo,
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crypto/crypto,
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peerid,
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protocols/protocol,
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muxers/muxer,
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muxers/mplex/mplex,
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protocols/secure/secio,
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protocols/secure/secure]
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const TestCodec = "/test/proto/1.0.0" # custom protocol string
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type
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TestProto = ref object of LPProtocol # declare a custom protocol
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method init(p: TestProto) {.gcsafe.} =
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# handle incoming connections in closure
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proc handle(conn: Connection, proto: string) {.async, gcsafe.} =
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echo "Got from remote - ", cast[string](await conn.readLp(1024))
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await conn.writeLp("Hello!")
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await conn.close()
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p.codec = TestCodec # init proto with the correct string id
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p.handler = handle # set proto handler
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proc createSwitch(ma: MultiAddress): (Switch, PeerInfo) =
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## Helper to create a swith
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let seckey = PrivateKey.random(RSA) # use a random key for peer id
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var peerInfo = PeerInfo.init(seckey) # create a peer id and assign
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peerInfo.addrs.add(ma) # set this peer's multiaddresses (can be any number)
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let identify = newIdentify(peerInfo) # create the identify proto
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proc createMplex(conn: Connection): Muxer =
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# helper proc to create multiplexers,
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# use this to perform any custom setup up,
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# such as adjusting timeout or anything else
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# that the muxer requires
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result = newMplex(conn)
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let mplexProvider = newMuxerProvider(createMplex, MplexCodec) # create multiplexer
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let transports = @[Transport(newTransport(TcpTransport))] # add all transports (tcp only for now, but can be anything in the future)
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let muxers = {MplexCodec: mplexProvider}.toTable() # add all muxers
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let secureManagers = {SecioCodec: Secure(Secio.new(seckey))}.toTable() # setup the secio and any other secure provider
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# create the switch
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let switch = newSwitch(peerInfo,
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transports,
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identify,
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muxers,
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secureManagers)
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result = (switch, peerInfo)
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proc main() {.async, gcsafe.} =
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let ma1: MultiAddress = Multiaddress.init("/ip4/0.0.0.0/tcp/0")
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let ma2: MultiAddress = Multiaddress.init("/ip4/0.0.0.0/tcp/0")
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var peerInfo1, peerInfo2: PeerInfo
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var switch1, switch2: Switch
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(switch1, peerInfo1) = createSwitch(ma1) # create node 1
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# setup the custom proto
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let testProto = new TestProto
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testProto.init() # run it's init method to perform any required initialization
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switch1.mount(testProto) # mount the proto
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var switch1Fut = await switch1.start() # start the node
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(switch2, peerInfo2) = createSwitch(ma2) # create node 2
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var switch2Fut = await switch2.start() # start second node
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let conn = await switch2.dial(switch1.peerInfo, TestCodec) # dial the first node
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await conn.writeLp("Hello!") # writeLp send a length prefixed buffer over the wire
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# readLp reads length prefixed bytes and returns a buffer without the prefix
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echo "Remote responded with - ", cast[string](await conn.readLp(1024))
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await allFutures(switch1.stop(), switch2.stop()) # close connections and shutdown all transports
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await allFutures(switch1Fut & switch2Fut) # wait for all transports to shutdown
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waitFor(main())
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```
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For more concrete examples, you can look at the [hello world example](../examples/helloworld.nim) or the [direct chat](../examples/directchat.nim)
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when not(compileOption("threads")):
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{.fatal: "Please, compile this program with the --threads:on option!".}
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import tables, strformat, strutils, bearssl
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import chronos # an efficient library for async
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import ../libp2p/[switch, # manage transports, a single entry point for dialing and listening
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builders, # helper to build the switch object
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multistream, # tag stream with short header to identify it
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multicodec, # multicodec utilities
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crypto/crypto, # cryptographic functions
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errors, # error handling utilities
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protocols/identify, # identify the peer info of a peer
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stream/connection, # create and close stream read / write connections
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transports/transport, # listen and dial to other peers using p2p protocol
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transports/tcptransport, # listen and dial to other peers using client-server protocol
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multiaddress, # encode different addressing schemes. For example, /ip4/7.7.7.7/tcp/6543 means it is using IPv4 protocol and TCP
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peerinfo, # manage the information of a peer, such as peer ID and public / private key
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peerid, # Implement how peers interact
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protocols/protocol, # define the protocol base type
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protocols/secure/secure, # define the protocol of secure connection
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protocols/secure/secio, # define the protocol of secure input / output, allows encrypted communication that uses public keys to validate signed messages instead of a certificate authority like in TLS
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muxers/muxer, # define an interface for stream multiplexing, allowing peers to offer many protocols over a single connection
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muxers/mplex/mplex] # define some contants and message types for stream multiplexing
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import
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strformat, strutils, bearssl,
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stew/byteutils,
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chronos,
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../libp2p
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const ChatCodec = "/nim-libp2p/chat/1.0.0"
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const DefaultAddr = "/ip4/127.0.0.1/tcp/55505"
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const DefaultAddr = "/ip4/127.0.0.1/tcp/0"
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const Help = """
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Commands: /[?|hep|connect|disconnect|exit]
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Commands: /[?|help|connect|disconnect|exit]
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help: Prints this help
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connect: dials a remote peer
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disconnect: ends current session
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exit: closes the chat
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"""
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type ChatProto = ref object of LPProtocol
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switch: Switch # a single entry point for dialing and listening to peer
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transp: StreamTransport # transport streams between read & write file descriptor
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conn: Connection # create and close read & write stream
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connected: bool # if the node is connected to another peer
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started: bool # if the node has started
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type
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Chat = ref object
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switch: Switch # a single entry point for dialing and listening to peer
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stdinReader: StreamTransport # transport streams between read & write file descriptor
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conn: Connection # connection to the other peer
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connected: bool # if the node is connected to another peer
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proc readAndPrint(p: ChatProto) {.async.} =
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while true:
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var strData = await p.conn.readLp(1024)
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strData &= '\0'.uint8
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var str = cast[cstring](addr strdata[0])
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echo $p.switch.peerInfo.peerId & ": " & $str
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await sleepAsync(100.millis)
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##
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# Stdout helpers, to write the prompt
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##
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proc writePrompt(c: Chat) =
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if c.connected:
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stdout.write '\r' & $c.switch.peerInfo.peerId & ": "
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stdout.flushFile()
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proc dialPeer(p: ChatProto, address: string) {.async.} =
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proc writeStdout(c: Chat, str: string) =
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echo '\r' & str
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c.writePrompt()
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##
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# Chat Protocol
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##
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const ChatCodec = "/nim-libp2p/chat/1.0.0"
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type
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ChatProto = ref object of LPProtocol
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proc new(T: typedesc[ChatProto], c: Chat): T =
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let chatproto = T()
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# create handler for incoming connection
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proc handle(stream: Connection, proto: string) {.async.} =
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if c.connected and not c.conn.closed:
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c.writeStdout "a chat session is already in progress - refusing incoming peer!"
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await stream.close()
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else:
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await c.handlePeer(stream)
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await stream.close()
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# assign the new handler
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chatproto.handler = handle
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chatproto.codec = ChatCodec
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return chatproto
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##
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# Chat application
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##
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proc handlePeer(c: Chat, conn: Connection) {.async.} =
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# Handle a peer (incoming or outgoing)
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try:
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c.conn = conn
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c.connected = true
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c.writeStdout $conn.peerId & " connected"
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# Read loop
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while true:
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let
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strData = await conn.readLp(1024)
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str = string.fromBytes(strData)
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c.writeStdout $conn.peerId & ": " & $str
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except LPStreamEOFError:
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c.writeStdout $conn.peerId & " disconnected"
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proc dialPeer(c: Chat, address: string) {.async.} =
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# Parse and dial address
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let
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multiAddr = MultiAddress.init(address).tryGet()
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# split the peerId part /p2p/...
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wireAddr = ip4Addr & tcpAddr
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echo &"dialing peer: {multiAddr}"
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p.conn = await p.switch.dial(remotePeer, @[wireAddr], ChatCodec)
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p.connected = true
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asyncSpawn p.readAndPrint()
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asyncSpawn c.handlePeer(await c.switch.dial(remotePeer, @[wireAddr], ChatCodec))
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proc writeAndPrint(p: ChatProto) {.async.} =
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proc readLoop(c: Chat) {.async.} =
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while true:
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if not p.connected:
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if not c.connected:
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echo "type an address or wait for a connection:"
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echo "type /[help|?] for help"
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let line = await p.transp.readLine()
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if line.startsWith("/help") or line.startsWith("/?") or not p.started:
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c.writePrompt()
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let line = await c.stdinReader.readLine()
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if line.startsWith("/help") or line.startsWith("/?"):
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echo Help
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continue
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if line.startsWith("/disconnect"):
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echo "Ending current session"
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if p.connected and p.conn.closed.not:
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await p.conn.close()
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p.connected = false
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c.writeStdout "Ending current session"
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if c.connected and c.conn.closed.not:
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await c.conn.close()
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c.connected = false
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elif line.startsWith("/connect"):
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if p.connected:
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var yesno = "N"
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echo "a session is already in progress, do you want end it [y/N]?"
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yesno = await p.transp.readLine()
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if yesno.cmpIgnoreCase("y") == 0:
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await p.conn.close()
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p.connected = false
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elif yesno.cmpIgnoreCase("n") == 0:
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continue
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else:
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echo "unrecognized response"
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continue
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echo "enter address of remote peer"
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let address = await p.transp.readLine()
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c.writeStdout "enter address of remote peer"
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let address = await c.stdinReader.readLine()
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if address.len > 0:
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await p.dialPeer(address)
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await c.dialPeer(address)
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elif line.startsWith("/exit"):
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if p.connected and p.conn.closed.not:
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await p.conn.close()
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p.connected = false
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if c.connected and c.conn.closed.not:
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await c.conn.close()
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c.connected = false
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await p.switch.stop()
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echo "quitting..."
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await c.switch.stop()
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c.writeStdout "quitting..."
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quit(0)
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else:
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if p.connected:
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await p.conn.writeLp(line)
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if c.connected:
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await c.conn.writeLp(line)
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else:
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try:
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if line.startsWith("/") and "p2p" in line:
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await p.dialPeer(line)
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except:
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await c.dialPeer(line)
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except CatchableError as exc:
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echo &"unable to dial remote peer {line}"
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echo getCurrentExceptionMsg()
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proc readWriteLoop(p: ChatProto) {.async.} =
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await p.writeAndPrint()
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proc newChatProto(switch: Switch, transp: StreamTransport): ChatProto =
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var chatproto = ChatProto(switch: switch, transp: transp, codecs: @[ChatCodec])
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# create handler for incoming connection
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proc handle(stream: Connection, proto: string) {.async.} =
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if chatproto.connected and not chatproto.conn.closed:
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echo "a chat session is already in progress - disconnecting!"
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await stream.close()
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else:
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chatproto.conn = stream
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chatproto.connected = true
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await chatproto.readAndPrint()
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# assign the new handler
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chatproto.handler = handle
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return chatproto
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echo exc.msg
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proc readInput(wfd: AsyncFD) {.thread.} =
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## This procedure performs reading from `stdin` and sends data over
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## This thread performs reading from `stdin` and sends data over
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## pipe to main thread.
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let transp = fromPipe(wfd)
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let line = stdin.readLine()
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discard waitFor transp.write(line & "\r\n")
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proc processInput(rfd: AsyncFD, rng: ref BrHmacDrbgContext) {.async.} =
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let transp = fromPipe(rfd)
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proc main() {.async.} =
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let
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rng = newRng() # Single random number source for the whole application
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let seckey = PrivateKey.random(RSA, rng[]).get()
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var localAddress = DefaultAddr
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while true:
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echo &"Type an address to bind to or Enter to use the default {DefaultAddr}"
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let a = await transp.readLine()
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try:
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if a.len > 0:
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localAddress = a
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break
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# uise default
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break
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except:
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echo "invalid address"
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localAddress = DefaultAddr
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continue
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# Pipe to read stdin from main thread
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(rfd, wfd) = createAsyncPipe()
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stdinReader = fromPipe(rfd)
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var thread: Thread[AsyncFD]
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thread.createThread(readInput, wfd)
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var localAddress = MultiAddress.init(DefaultAddr).tryGet()
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var switch = SwitchBuilder
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.init()
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.withRng(rng)
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.withPrivateKey(seckey)
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.withAddress(MultiAddress.init(localAddress).tryGet())
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.new()
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.withRng(rng) # Give the application RNG
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.withAddress(localAddress)
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.withTcpTransport() # Use TCP as transport
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.withMplex() # Use Mplex as muxer
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.withNoise() # Use Noise as secure manager
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.build()
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let chatProto = newChatProto(switch, transp)
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switch.mount(chatProto)
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let chat = Chat(
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switch: switch,
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stdinReader: stdinReader)
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switch.mount(ChatProto.new(chat))
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let libp2pFuts = await switch.start()
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chatProto.started = true
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let id = $switch.peerInfo.peerId
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echo "PeerID: " & id
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@ -187,19 +187,7 @@ proc processInput(rfd: AsyncFD, rng: ref BrHmacDrbgContext) {.async.} =
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for a in switch.peerInfo.addrs:
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echo &"{a}/p2p/{id}"
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await chatProto.readWriteLoop()
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await chat.readLoop()
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await allFuturesThrowing(libp2pFuts)
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proc main() {.async.} =
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let rng = newRng() # Singe random number source for the whole application
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let (rfd, wfd) = createAsyncPipe()
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if rfd == asyncInvalidPipe or wfd == asyncInvalidPipe:
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raise newException(ValueError, "Could not initialize pipe!")
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var thread: Thread[AsyncFD]
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thread.createThread(readInput, wfd)
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await processInput(rfd, rng)
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when isMainModule: # isMainModule = true when the module is compiled as the main file
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waitFor(main())
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waitFor(main())
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@ -0,0 +1,92 @@
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import bearssl
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import chronos # an efficient library for async
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import stew/byteutils # various utils
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import ../libp2p # when installed through nimble, just use `import libp2p`
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##
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# Create our custom protocol
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##
|
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const TestCodec = "/test/proto/1.0.0" # custom protocol string identifier
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|
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type
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TestProto = ref object of LPProtocol # declare a custom protocol
|
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|
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proc new(T: typedesc[TestProto]): T =
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# every incoming connections will be in handled in this closure
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proc handle(conn: Connection, proto: string) {.async, gcsafe.} =
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echo "Got from remote - ", string.fromBytes(await conn.readLp(1024))
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await conn.writeLp("Roger p2p!")
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# We must close the connections ourselves when we're done with it
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await conn.close()
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return T(codecs: @[TestCodec], handler: handle)
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##
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# Helper to create a switch/node
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##
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proc createSwitch(ma: MultiAddress, rng: ref BrHmacDrbgContext): Switch =
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var switch = SwitchBuilder
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.new()
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.withRng(rng) # Give the application RNG
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.withAddress(ma) # Our local address(es)
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.withTcpTransport() # Use TCP as transport
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.withMplex() # Use Mplex as muxer
|
||||
.withNoise() # Use Noise as secure manager
|
||||
.build()
|
||||
|
||||
result = switch
|
||||
|
||||
##
|
||||
# The actual application
|
||||
##
|
||||
proc main() {.async, gcsafe.} =
|
||||
let
|
||||
rng = newRng() # Single random number source for the whole application
|
||||
# port 0 will take a random available port
|
||||
# `tryGet` will throw an exception if the Multiaddress failed
|
||||
# (for instance, if the address is not well formatted)
|
||||
ma1 = Multiaddress.init("/ip4/0.0.0.0/tcp/0").tryGet()
|
||||
ma2 = Multiaddress.init("/ip4/0.0.0.0/tcp/0").tryGet()
|
||||
|
||||
# setup the custom proto
|
||||
let testProto = TestProto.new()
|
||||
|
||||
# setup the two nodes
|
||||
let
|
||||
switch1 = createSwitch(ma1, rng) #Create the two switches
|
||||
switch2 = createSwitch(ma2, rng)
|
||||
|
||||
# mount the proto on switch1
|
||||
# the node will now listen for this proto
|
||||
# and call the handler everytime a client request it
|
||||
switch1.mount(testProto)
|
||||
|
||||
# Start the nodes. This will start the transports
|
||||
# and listen on each local addresses
|
||||
let
|
||||
switch1Fut = await switch1.start()
|
||||
switch2Fut = await switch2.start()
|
||||
|
||||
# the node addrs is populated with it's
|
||||
# actual port during the start
|
||||
|
||||
# use the second node to dial the first node
|
||||
# using the first node peerid and address
|
||||
# and specify our custom protocol codec
|
||||
let conn = await switch2.dial(switch1.peerInfo.peerId, switch1.peerInfo.addrs, TestCodec)
|
||||
|
||||
# conn is now a fully setup connection, we talk directly to the node1 custom protocol handler
|
||||
await conn.writeLp("Hello p2p!") # writeLp send a length prefixed buffer over the wire
|
||||
|
||||
# readLp reads length prefixed bytes and returns a buffer without the prefix
|
||||
echo "Remote responded with - ", string.fromBytes(await conn.readLp(1024))
|
||||
|
||||
# We must close the connection ourselves when we're done with it
|
||||
await conn.close()
|
||||
|
||||
await allFutures(switch1.stop(), switch2.stop()) # close connections and shutdown all transports
|
||||
await allFutures(switch1Fut & switch2Fut) # wait for all transports to shutdown
|
||||
|
||||
waitFor(main())
|
|
@ -0,0 +1,108 @@
|
|||
Hi all, welcome to the first article of the nim-libp2p's tutorial series!
|
||||
|
||||
_This tutorial is for everyone who is interested in building peer-to-peer chatting applications. No Nim programming experience is needed._
|
||||
|
||||
To give you a quick overview, **Nim** is the programming language we are using and **nim-libp2p** is the Nim implementation of [libp2p](https://libp2p.io/), a modular library that enables the development of peer-to-peer network applications.
|
||||
|
||||
Hope you'll find it helpful in your journey of learning. Happy coding! ;)
|
||||
|
||||
# Before you start
|
||||
The only prerequisite here is [Nim](https://nim-lang.org/), the programming language with a Python-like syntax and a performance similar to C. Detailed information can be found [here](https://nim-lang.org/docs/tut1.html).
|
||||
|
||||
Install Nim via their official website: [https://nim-lang.org/install.html](https://nim-lang.org/install.html)
|
||||
Check Nim's installation via `nim --version` and its package manager Nimble via `nimble --version`.
|
||||
|
||||
You can now install the latest version of `nim-libp2p`:
|
||||
```bash
|
||||
nimble install libp2p@#master
|
||||
```
|
||||
|
||||
# A simple ping application
|
||||
We'll start by creating a simple application, which is starting two libp2p [switch](https://docs.libp2p.io/concepts/stream-multiplexing/#switch-swarm), and pinging each other using the [Ping](https://docs.libp2p.io/concepts/protocols/#ping) protocol.
|
||||
|
||||
_TIP: You can extract the code from this tutorial by running `nim c -r tools/markdown_runner.nim examples/tutorial_1_connect.md` in the libp2p folder!_
|
||||
|
||||
Let's create a `part1.nim`, and import our dependencies:
|
||||
```nim
|
||||
import bearssl
|
||||
import chronos
|
||||
|
||||
import libp2p
|
||||
import libp2p/protocols/ping
|
||||
```
|
||||
[bearssl](https://github.com/status-im/nim-bearssl) is used as a [cryptographic pseudorandom number generator](https://en.wikipedia.org/wiki/Cryptographically-secure_pseudorandom_number_generator)
|
||||
[chronos](https://github.com/status-im/nim-chronos) the asynchronous framework used by `nim-libp2p`
|
||||
|
||||
Next, we'll create an helper procedure to create our switches. A switch needs a bit of configuration, and it will be easier to do this configuration only once:
|
||||
```nim
|
||||
proc createSwitch(ma: MultiAddress, rng: ref BrHmacDrbgContext): Switch =
|
||||
var switch = SwitchBuilder
|
||||
.new()
|
||||
.withRng(rng) # Give the application RNG
|
||||
.withAddress(ma) # Our local address(es)
|
||||
.withTcpTransport() # Use TCP as transport
|
||||
.withMplex() # Use Mplex as muxer
|
||||
.withNoise() # Use Noise as secure manager
|
||||
.build()
|
||||
|
||||
return switch
|
||||
```
|
||||
This will create a switch using [Mplex](https://docs.libp2p.io/concepts/stream-multiplexing/) as a multiplexer, Noise to secure the communication, and TCP as an underlying transport.
|
||||
|
||||
You can of course tweak this, to use a different or multiple transport, or tweak the configuration of Mplex and Noise, but this is some sane defaults that we'll use going forward.
|
||||
|
||||
|
||||
Let's now start to create our main procedure:
|
||||
```nim
|
||||
proc main() {.async, gcsafe.} =
|
||||
let
|
||||
rng = newRng()
|
||||
localAddress = MultiAddress.init("/ip4/0.0.0.0/tcp/0").tryGet()
|
||||
pingProtocol = Ping.new(rng=rng)
|
||||
```
|
||||
We created some variables that we'll need for the rest of the application: the global `rng` instance, our `localAddress`, and an instance of the `Ping` protocol.
|
||||
The address is in the [MultiAddress](https://github.com/multiformats/multiaddr) format. The port `0` means "take any port available".
|
||||
|
||||
`tryGet` is procedure which is part of the [nim-result](https://github.com/arnetheduck/nim-result/), that will throw an exception if the supplied MultiAddress is not valid.
|
||||
|
||||
We can now create our two switches:
|
||||
```nim
|
||||
let
|
||||
switch1 = createSwitch(localAddress, rng)
|
||||
switch2 = createSwitch(localAddress, rng)
|
||||
|
||||
switch1.mount(pingProtocol)
|
||||
|
||||
let
|
||||
switch1Fut = await switch1.start()
|
||||
switch2Fut = await switch2.start()
|
||||
```
|
||||
We've **mounted** the `pingProtocol` on our first switch. This means that the first switch will actually listen for any ping requests coming in, and handle them accordingly.
|
||||
|
||||
Now that we've started the nodes, they are listening for incoming peers.
|
||||
We can find out which port was attributed, and the resulting local addresses, by using `switch1.peerInfo.addrs`.
|
||||
|
||||
We'll **dial** the first switch from the second one, by specifying it's **Peer ID**, it's **MultiAddress** and the **`Ping` protocol codec**:
|
||||
```nim
|
||||
let conn = await switch2.dial(switch1.peerInfo.peerId, switch1.peerInfo.addrs, PingCodec)
|
||||
```
|
||||
We now have a `Ping` connection setup between the second and the first switch, we can use it to actually ping the node:
|
||||
```nim
|
||||
# ping the other node and echo the ping duration
|
||||
echo "ping: ", await pingProtocol.ping(conn)
|
||||
|
||||
# We must close the connection ourselves when we're done with it
|
||||
await conn.close()
|
||||
```
|
||||
|
||||
And that's it! Just a little bit of cleanup: shutting down the switches, waiting for them to stop, and we'll call our `main` procedure:
|
||||
```nim
|
||||
await allFutures(switch1.stop(), switch2.stop()) # close connections and shutdown all transports
|
||||
await allFutures(switch1Fut & switch2Fut) # wait for all transports to shutdown
|
||||
|
||||
waitFor(main())
|
||||
```
|
||||
|
||||
You can now run this program using `nim c -r part1.nim`, and you should see the dialing sequence, ending with a ping output.
|
||||
|
||||
In the [next tutorial](tutorial_2_customproto.md), we'll look at how to create our own custom protocol.
|
|
@ -0,0 +1,82 @@
|
|||
In the [previous tutorial](tutorial_1_connect.md), we've looked at how to create a simple ping program using the `nim-libp2p`.
|
||||
|
||||
We'll now look at how to create a custom protocol inside the libp2p
|
||||
|
||||
# Custom protocol in libp2p
|
||||
Let's create a `part2.nim`, and import our dependencies:
|
||||
```nim
|
||||
import bearssl
|
||||
import chronos
|
||||
import stew/byteutils
|
||||
|
||||
import libp2p
|
||||
```
|
||||
This is similar to the first tutorial, except we don't need to import the `Ping` protocol.
|
||||
|
||||
Next, we'll declare our custom protocol
|
||||
```nim
|
||||
const TestCodec = "/test/proto/1.0.0"
|
||||
|
||||
type TestProto = ref object of LPProtocol
|
||||
```
|
||||
|
||||
We've set a [protocol ID](https://docs.libp2p.io/concepts/protocols/#protocol-ids), and created a custom `LPProtocol`. In a more complex protocol, we could use this structure to store interesting variables.
|
||||
|
||||
A protocol generally has two part: and handling/server part, and a dialing/client part.
|
||||
Theses two parts can be identical, but in our trivial protocol, the server will wait for a message from the client, and the client will send a message, so we have to handle the two cases separately.
|
||||
|
||||
Let's start with the server part:
|
||||
```nim
|
||||
proc new(T: typedesc[TestProto]): T =
|
||||
# every incoming connections will in be handled in this closure
|
||||
proc handle(conn: Connection, proto: string) {.async, gcsafe.} =
|
||||
echo "Got from remote - ", string.fromBytes(await conn.readLp(1024))
|
||||
# We must close the connections ourselves when we're done with it
|
||||
await conn.close()
|
||||
|
||||
return T(codecs: @[TestCodec], handler: handle)
|
||||
```
|
||||
This is a constructor for our `TestProto`, that will specify our `codecs` and a `handler`, which will be called for each incoming peer asking for this protocol.
|
||||
In our handle, we simply read a message from the connection and `echo` it.
|
||||
|
||||
We can now create our client part:
|
||||
```nim
|
||||
proc hello(p: TestProto, conn: Connection) {.async.} =
|
||||
await conn.writeLp("Hello p2p!")
|
||||
```
|
||||
Again, pretty straight-forward, we just send a message on the connection.
|
||||
|
||||
We can now create our main procedure:
|
||||
```nim
|
||||
proc main() {.async, gcsafe.} =
|
||||
let
|
||||
rng = newRng()
|
||||
testProto = TestProto.new()
|
||||
switch1 = newStandardSwitch(rng=rng)
|
||||
switch2 = newStandardSwitch(rng=rng)
|
||||
|
||||
switch1.mount(testProto)
|
||||
|
||||
let
|
||||
switch1Fut = await switch1.start()
|
||||
switch2Fut = await switch2.start()
|
||||
|
||||
conn = await switch2.dial(switch1.peerInfo.peerId, switch1.peerInfo.addrs, TestCodec)
|
||||
|
||||
await testProto.hello(conn)
|
||||
|
||||
# We must close the connection ourselves when we're done with it
|
||||
await conn.close()
|
||||
|
||||
await allFutures(switch1.stop(), switch2.stop()) # close connections and shutdown all transports
|
||||
await allFutures(switch1Fut & switch2Fut) # wait for all transports to shutdown
|
||||
```
|
||||
|
||||
This is very similar to the first tutorial's `main`, the only noteworthy difference is that we use `newStandardSwitch`, which is similar to `createSwitch` but is bundled directly in libp2p
|
||||
|
||||
We can now wrap our program by calling our main proc:
|
||||
```nim
|
||||
waitFor(main())
|
||||
```
|
||||
|
||||
And that's it!
|
|
@ -33,12 +33,18 @@ proc runTest(filename: string, verify: bool = true, sign: bool = true,
|
|||
exec excstr & " -d:chronicles_log_level=INFO -r" & " tests/" & filename
|
||||
rmFile "tests/" & filename.toExe
|
||||
|
||||
proc buildSample(filename: string) =
|
||||
proc buildSample(filename: string, run = false) =
|
||||
var excstr = "nim c --opt:speed --threads:on -d:debug --verbosity:0 --hints:off"
|
||||
excstr.add(" --warning[CaseTransition]:off --warning[ObservableStores]:off --warning[LockLevel]:off")
|
||||
excstr.add(" examples/" & filename)
|
||||
exec excstr
|
||||
rmFile "examples" & filename.toExe
|
||||
if run:
|
||||
exec "./examples/" & filename.toExe
|
||||
rmFile "examples/" & filename.toExe
|
||||
|
||||
proc buildTutorial(filename: string) =
|
||||
discard gorge "cat " & filename & " | nim c -r --hints:off tools/markdown_runner.nim | " &
|
||||
" nim --warning[CaseTransition]:off --warning[ObservableStores]:off --warning[LockLevel]:off c -"
|
||||
|
||||
task testnative, "Runs libp2p native tests":
|
||||
runTest("testnative")
|
||||
|
@ -75,6 +81,7 @@ task test, "Runs the test suite":
|
|||
exec "nimble testdaemon"
|
||||
exec "nimble testinterop"
|
||||
exec "nimble testfilter"
|
||||
exec "nimble examples_build"
|
||||
|
||||
task test_slim, "Runs the test suite":
|
||||
exec "nimble testnative"
|
||||
|
@ -84,3 +91,6 @@ task test_slim, "Runs the test suite":
|
|||
|
||||
task examples_build, "Build the samples":
|
||||
buildSample("directchat")
|
||||
buildSample("helloworld", true)
|
||||
buildTutorial("examples/tutorial_1_connect.md")
|
||||
buildTutorial("examples/tutorial_2_customproto.md")
|
||||
|
|
|
@ -0,0 +1,25 @@
|
|||
import os, osproc, streams, strutils
|
||||
import parseutils
|
||||
|
||||
let contents =
|
||||
if paramCount() > 0:
|
||||
readFile(paramStr(1))
|
||||
else:
|
||||
stdin.readAll()
|
||||
var index = 0
|
||||
|
||||
const startDelim = "```nim\n"
|
||||
const endDelim = "\n```"
|
||||
while true:
|
||||
let startOfBlock = contents.find(startDelim, start = index)
|
||||
if startOfBlock == -1: break
|
||||
|
||||
let endOfBlock = contents.find(endDelim, start = startOfBlock + startDelim.len)
|
||||
if endOfBlock == -1:
|
||||
quit "Unfinished block!"
|
||||
|
||||
let code = contents[startOfBlock + startDelim.len .. endOfBlock]
|
||||
|
||||
echo code
|
||||
|
||||
index = endOfBlock + endDelim.len
|
Loading…
Reference in New Issue