Added broadcast example

Examples/Broadcast.py

@@ -0,0 +1,93 @@
+##########################################################
+# 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_utilitites"
+
+# 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.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 that demonstrates sending and receiving unencrypted 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="path to alternative Reticulum config directory", 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("")
+		exit()