M1 - Listening router

[widforss]

We want to split up the handlers for the different RPCs, so that we can work on each in parallel. Write a router for this and organize a file that can contain these handlers.

Part of this task is also to create a method for serializing and deserializing the RPCs

Definition of done

A socket can receive a serialized message, parse it and send it to a different function for handling.

[widforss]

We have to decide on a protocol for use in the network. I propose that we use JSON over UDP on port 9000.

A (STORE) RPC would look something like this:

{
    "type": "RPC",
    "name": "STORE",
    "requestId": "52CB4053946C1B4BD845A7C7E428929518285B9B",
    "source": "252CFFA0AFD27A039A9B497D0BD1B2090DC9ABAF",
    "destination": "4E7CA1ADDADD7C4BAB0A3AD27A7933B9C059D307",
    "params": ["test-value"]
}

And a response (to a FIND-NODE request) would look something like this:

{
    "type": "RETURN",
    "name": "FIND-NODE",
    "requestId": "5C46922B5B76C14E514CCA6AB2E5628921EEE1AD",
    "source": "4E7CA1ADDADD7C4BAB0A3AD27A7933B9C059D307",
    "destination": "252CFFA0AFD27A039A9B497D0BD1B2090DC9ABAF",
    "params": [
        ["10.0.0.1", 9000, "9BBF47A02727AF5E7F76F36901AE61478FBDA0FF"],
        ["10.0.0.2", 9000, "588CDD1961A7A736F8AB2C7ABACD42564AD69C8D"],
        ["10.0.0.3", 9000, "4113EFDD1A0A22717268C5F90E23C7E74B63088D"]
    ]
}

[freeolo]

Generally positive.

[widforss]

Here's some psuedo-code showing what I mean with a router.

func Listen(ip string, port int) {
	let socket := new Socket("0.0.0.0:9000");
	loop {
		let serialized_message: string = socket.receive();
		let message: Message = deserialize(serialized_message);
		switch((message.type, message.name)) {
			case ("RPC", "PING"):
				handlerRpcPing(message);
			case ("RPC", "FIND-NODE"):
				handlerRpcFindNode(message);
			case ("RPC", "FIND-VALUE"):
				handlerRpcFindData(message);
			case ("RPC", "STORE"):
				handlerRpcStore(message);
			case ("RETURN", "PING"):
				handlerReturnPing(message);
			case ("RETURN", "FIND-NODE"):
				handlerReturnFindNode(message);
			case ("RETURN", "FIND-VALUE"):
				handlerReturnFindData(message);
			case ("RETURN", "STORE"):
				handlerReturnStore(message);
			default:
				continue;
		}
	}
}