TCPMon

TCPMon is a program that allows you to send and receive data using TCP connections.
It's useful for debugging a protocol that you might be implementing.

Schema

Since working with bytes directly can be difficult at times, you can use Schema to describe a schema for the data you're sending and receiving.

Each data monitor instance can have a schema loaded, Blaze can also work with schemas.
Below is an example of a schema.

enum packet_type :: uint8 {
    0: CHANNEL_LIST;
    1: MESSAGE;
}

struct channel {
    name :: string;
}

@entry
struct packet {
    type :: packet_type;
    
    if(type == packet_type.CHANNEL_LIST) {
        count :: uint8;
        channels :: channel[count];
    } else if(type == packet_type.MESSAGE) {
        message :: string;
    }
}

Blaze

Scripting is done using the Blaze programming language.

Each TCPMon client instance has an internal blaze module which contains the following public variables:

Variable	Description
connection	The client connection instance

TCPMon also has a main internal module which provides multiple libraries:

Variable	Description
console	Allows interaction with the console
parse	Convert values into different types
schema	Loading schemas for decoding data
module	Load blaze modules
packet	Library for handling packets

The module hierarchy in TCPMon goes as follows:

• Internal Module
  • Connection Module
    • User module
  • Connection Module
    • User module

All of the variables described above can be accessed from your script by using extern var ...;

Below is an example of a Blaze script (C# highligting)

extern var console;
extern var connection;
extern var parse;
extern var packet;
extern var schema;

var packet_schema = schema.load("packet.schema");

func main() {
    console.print("Hello World");
}

event connection.received(data) {
    var decoded = data.decode(packet_schema);
    
    // print out the decoded object
    for(var pair : decoded)
        console.print(pair[0] + ": " + parse.str(pair[1]));
        
    // send a response
    var resp = packet.builder()
        .string("Hello World");

    connection.send(resp);
}

event connection.closed() {
    console.print("Bye");
}