move chat.py into examples directory

examples/chat/chat.py

@@ -0,0 +1,109 @@
+#!/bin/env python3
+import sys
+from os.path import dirname, abspath
+sys.path.append(dirname(dirname(dirname(abspath(__file__)))))
+
+import asyncio
+
+import click
+from libp2p.libp2p import Libp2p
+from network.multiaddr import MultiAddr
+
+# TODO: change once muxed_connection supports extracting protocol id from messages
+PROTOCOL_ID = '/echo/1.0.0'
+
+
+async def read_data(stream):
+    while True:
+        read_string = (await stream.read()).decode()
+
+        if not read_string:
+            return
+
+        if read_string != "\n":
+            # Green console colour: 	\x1b[32m
+            # Reset console colour: 	\x1b[0m
+            print("\x1b[32m%s\x1b[0m" % read_string)
+
+
+async def write_data(stream):
+    loop = asyncio.get_event_loop()
+
+    while True:
+        line = await loop.run_in_executor(None, sys.stdin.readline)
+        await stream.write(line.encode())
+
+
+async def run(port, destination):
+
+    if not destination:
+        lib = Libp2p(transport_opt=["/ip4/127.0.0.1/tcp/%s/p2p/hostA" % port])
+        host = await lib.new_node()
+
+        async def stream_handler(stream):
+            asyncio.ensure_future(read_data(stream))
+            asyncio.ensure_future(write_data(stream))
+
+        host.set_stream_handler(PROTOCOL_ID, stream_handler)
+
+        port = None
+        for listener in host.network.listeners.values():
+            for addr in listener.get_addrs():
+                addr_dict = addr.to_options()
+                if addr_dict['transport'] == 'tcp':
+                    port = addr_dict['port']
+                    break
+
+        if not port:
+            raise RuntimeError("was not able to find the actual local port")
+
+        print("Run './chat.py --port %s -d /ip4/127.0.0.1/tcp/%s/p2p/%s' on another console.\n" % (int(port)+1, port, host.get_id().pretty()))
+        print("You can replace 127.0.0.1 with public IP as well.")
+        print("\nWaiting for incoming connection\n\n")
+
+    else:
+        lib = Libp2p(transport_opt=["/ip4/127.0.0.1/tcp/%s/p2p/hostB" % port])
+        host = await lib.new_node()
+
+        # TODO: improve multiaddr module to have proper function to do this
+        multiaddr = MultiAddr(destination)
+        ss = multiaddr.get_multiaddr_string().split('/')
+        peer_id = ss[-1]
+        addr = '/'.join(ss[:-2])
+
+        # Associate the peer with local ip address (see default parameters of Libp2p())
+        host.get_peerstore().add_addr(peer_id, addr, 10)
+
+        # Start a stream with the destination.
+        # Multiaddress of the destination peer is fetched from the peerstore using 'peerId'.
+        stream = await host.new_stream(peer_id, PROTOCOL_ID)
+
+        asyncio.ensure_future(read_data(stream))
+        asyncio.ensure_future(write_data(stream))
+
+
+@click.command()
+@click.option('--port', help='source port number', default=8000)
+@click.option('--destination', '-d', help="Destination multiaddr string")
+@click.option('--help', is_flag=True, default=False, help='display help')
+# @click.option('--debug', is_flag=True, default=False, help='Debug generates the same node ID on every execution')
+def main(port, destination, help):
+
+    if help:
+        print("This program demonstrates a simple p2p chat application using libp2p\n\n")
+        print("Usage: Run './chat -sp <SOURCE_PORT>' where <SOURCE_PORT> can be any port number.")
+        print("Now run './chat -d <MULTIADDR>' where <MULTIADDR> is multiaddress of previous listener host.")
+        return
+
+    loop = asyncio.get_event_loop()
+    try:
+        asyncio.ensure_future(run(port, destination))
+        loop.run_forever()
+    except KeyboardInterrupt:
+        pass
+    finally:
+        loop.close()
+
+
+if __name__ == '__main__':
+    main()