kaban-chat

A chat made in Rust to practice my skills

Developer's Guide

lib.rs

The library documentation itsself should be quite self-explaining, a part for the term 'Paket' (and the derived term). A paket is what I call a Message serialised with serde, binarized (put in bytes) and enclosed by the bytes Message::PAKET_<INIT/END>_U8.

Regarding the errors: the choice had to be made between generic ones which could easily be converted (on the trace of the anyhow crate) or a bit more precise ones (on the trace of the thiserror crate). The choice fell on the latter one.

• lib.rs:
  • enum TextValidityError
    • TooLong
  • enum MsgFromUtf8PaketError
    • NoInitDelimiter
    • NoEndDelimiter
    • SerdeJson
    • StringFromUtf8
    • EmptyPaket
  • enum MsgReaderError
    • conversion from various underlying errors
    • EmptyEntity

The server and client architecture

The server and the clients are exchanging Message(s), i.e. structs struct Message { username: String, content: String, }. In the server such Messages are then wrapped in a struct Dispatch { userid: integer, msg: Message, }. The server and the client have together this structure (approximatively) :

Loading

flowchart TB
    wr_manager1 --"sends Messages to"-->client_tcp_rd_loop1
    client_tcp_wr_loop1 --"sends Messages to"--> rd_manager1

    wr_manager2 -- "sends Messages to" -->client_tcp_rd_loop2
    client_tcp_wr_loop2 --"sends Messages to"--> rd_manager2

    CLIENT1 --"connects to"--> SERVER_MANAGER

    CLIENT2 --"connects to"--> SERVER_MANAGER
    
    subgraph CLIENT1 ["client 1"]
        direction LR
        stdin1-->wr_manager1
        rd_manager1-->stdout1
    end
    
    subgraph CLIENT2 ["client 2"]
        direction LR
        stdin2-->wr_manager2
        rd_manager2-->stdout2
    end
        
    subgraph SERVER
        client_handler1 --> client_tcp_rd_loop1 --"send dispatches to"--> 
            DISPATCHER --"forward dispatches to"--> client_tcp_wr_loop1
        client_handler1 --> client_tcp_wr_loop1
        SERVER_MANAGER --"delegates"--> client_handler1

        client_handler2 --> client_tcp_rd_loop2 --"send dispatches to"-->
        DISPATCHER --"forward dispatches to"--> client_tcp_wr_loop2
        client_handler2 --> client_tcp_wr_loop2
        SERVER_MANAGER --"delegates"--> client_handler2
    end

My Targets

• add the id pool and the id_pool token redemption for the graceful shutdown of client handlers in the server

• update naming in README.md

• merge all of this into the master branch

• graceful shutdown for the whole client

• graceful shutdown for the whole server

• merge this into master

• tracing in the lib

• tracing in the client

• tracing in the server

After this the project can be considered finished. Future projects might be implementing new features on this structure, as for example:

• adding a GUI
• adding encryption
• adding optimization of resources, letting tests be faster etc...