Broadcast.py

##########################################################
# This RNS example demonstrates broadcasting unencrypted #
# information to any listening destinations.             #
##########################################################

import sys
import argparse
import RNS

# Let's define an app name. We'll use this for all
# destinations we create. Since this basic example
# is part of a range of example utilities, we'll put
# them all within the app namespace "example_utilities"
APP_NAME = "example_utilities"

# This initialisation is executed when the program is started
def program_setup(configpath, channel=None):
    # We must first initialise Reticulum
    reticulum = RNS.Reticulum(configpath)
    
    # If the user did not select a "channel" we use
    # a default one called "public_information".
    # This "channel" is added to the destination name-
    # space, so the user can select different broadcast
    # channels.
    if channel == None:
        channel = "public_information"

    # We create a PLAIN destination. This is an uncencrypted endpoint
    # that anyone can listen to and send information to.
    broadcast_destination = RNS.Destination(
        None,
        RNS.Destination.IN,
        RNS.Destination.PLAIN,
        APP_NAME,
        "broadcast",
        channel
    )

    # We specify a callback that will get called every time
    # the destination receives data.
    broadcast_destination.set_packet_callback(packet_callback)
    
    # Everything's ready!
    # Let's hand over control to the main loop
    broadcastLoop(broadcast_destination)

def packet_callback(data, packet):
    # Simply print out the received data
    print("")
    print("Received data: "+data.decode("utf-8")+"\r\n> ", end="")
    sys.stdout.flush()

def broadcastLoop(destination):
    # Let the user know that everything is ready
    RNS.log(
        "Broadcast example "+
        RNS.prettyhexrep(destination.hash)+
        " running, enter text and hit enter to broadcast (Ctrl-C to quit)"
    )

    # We enter a loop that runs until the users exits.
    # If the user hits enter, we will send the information
    # that the user entered into the prompt.
    while True:
        print("> ", end="")
        entered = input()

        if entered != "":
            data    = entered.encode("utf-8")
            packet  = RNS.Packet(destination, data)
            packet.send()



##########################################################
#### Program Startup #####################################
##########################################################

# This part of the program gets run at startup,
# and parses input from the user, and then starts
# the program.
if __name__ == "__main__":
    try:
        parser = argparse.ArgumentParser(
            description="Reticulum example demonstrating sending and receiving broadcasts"
        )

        parser.add_argument(
            "--config",
            action="store",
            default=None,
            help="path to alternative Reticulum config directory",
            type=str
        )

        parser.add_argument(
            "--channel",
            action="store",
            default=None,
            help="broadcast channel name",
            type=str
        )

        args = parser.parse_args()

        if args.config:
            configarg = args.config
        else:
            configarg = None

        if args.channel:
            channelarg = args.channel
        else:
            channelarg = None

        program_setup(configarg, channelarg)

    except KeyboardInterrupt:
        print("")
        sys.exit(0)