This is a peer-to-peer (P2P) group message application based on TCP.
Group members are "nodes" where every node is an instance
of the program (src/node.py) and acts as both server and client.
Groups are formed by invitations and each member only maintains
connections with its invited members and the member that invited it.
The first member of a group has no inviter.
A group's topology is a tree and messages are relayed by nodes on the tree.
Packets (over TCP) are of fixed-length (128 bytes).
Python >= 3.9
Launch a node by
python3 src/node.py <name> <my-ip> <my-port> [inviter-ip] [inviter-port]
where the first node's inviter should be omitted.
Then you can type a line and press Enter
to send the line to all nodes on the tree.
At the same time any message sent by any node on the tree
is displayed on every node's stdout.
Certain control information is printed to stderr.
An empty input line terminates the current node.
Note that the termination of a node may split the group (tree)
into multiple smaller groups.
This program does not implement NAT hole punching. You can of course form a group inside a LAN, but if you want to form a group over the Internet then at least one peer should have a public IP address where other peers can connect to.