add broadcast by protocol example (#165)

python/examples/14-broadcast/main.py

@@ -0,0 +1,58 @@
+from uagents import Agent, Bureau, Context, Model, Protocol
+from uagents.setup import fund_agent_if_low
+
+# create agents
+# alice and bob will support the protocol
+# charles will try to reach all agents supporting the protocol
+alice = Agent(name="alice", seed="alice recovery phrase")
+bob = Agent(name="bob", seed="bob recovery phrase")
+charles = Agent(name="charles", seed="charles recovery phrase")
+
+fund_agent_if_low(alice.wallet.address())
+fund_agent_if_low(bob.wallet.address())
+fund_agent_if_low(charles.wallet.address())
+
+
+class BroadcastExampleRequest(Model):
+    pass
+
+
+class BroadcastExampleResponse(Model):
+    text: str
+
+
+# define protocol
+proto = Protocol(name="proto", version="1.0")
+
+
+@proto.on_message(model=BroadcastExampleRequest, replies=BroadcastExampleResponse)
+async def handle_request(ctx: Context, sender: str, _msg: BroadcastExampleRequest):
+    await ctx.send(sender, BroadcastExampleResponse(text=f"Hello from {ctx.name}"))
+
+
+# include protocol
+# Note: after the first registration on the almanac smart contract, it will
+# take about 5 minutes before the agents can be found through the protocol
+alice.include(proto)
+bob.include(proto)
+
+
+# let charles send the message to all agents supporting the protocol
+@charles.on_interval(period=5)
+async def say_hello(ctx: Context):
+    await ctx.experimental_broadcast(proto.digest, message=BroadcastExampleRequest())
+
+
+@charles.on_message(model=BroadcastExampleResponse)
+async def handle_response(ctx: Context, sender: str, msg: BroadcastExampleResponse):
+    ctx.logger.info(f"Received response from {sender}: {msg.text}")
+
+
+bureau = Bureau(port=8000, endpoint="http://localhost:8000/submit")
+bureau.add(alice)
+bureau.add(bob)
+bureau.add(charles)
+
+
+if __name__ == "__main__":
+    bureau.run()