rubbs

A Ruby gem for building telnet BBS servers with a declarative conversation flow DSL.

Installation

# Gemfile
gem 'bbs', git: 'https://git.teletype.hu/tools/rubbs.git'

Quick start

require 'bbs'

sessions = BBS::Store.new(path: 'data/sessions.csv', headers: %w[session_id timestamp name])

BBS.configure do |c|
  c.screens_dir = 'screens'
  c.stores      = [sessions]
  c.flow        = BBS::Flow.define do
    screen :welcome
    ask :name, prompt: "What is your name?"
    say "Hello, %{name}!", style: :success
    persist :name, store: sessions
  end
end

BBS::Server.start

Connect with telnet localhost 2323. The port defaults to 2323 and can be overridden with the BBS_PORT environment variable.

Configuration

BBS.configure yields a BBS::Config object:

Option	Default	Description
screens_dir	"screens"	Directory containing ERB screen files
stores	[]	List of BBS::Store instances
flow	—	A BBS::Flow object (required)
port	ENV["BBS_PORT"] || 2323	TCP port to listen on

Flow DSL

The entire dialogue is defined as a declarative BBS::Flow.define block.

Primitives

Primitive	Description
screen :name, **vars	Render an ERB screen from screens/; vars override/extend the context
banner "text", style:	Print a box-drawing ASCII banner
big_banner "text", style:, font:	Print a large FIGlet ASCII-art banner (default font: slant)
say "text", style:	Print a single styled line
ask :field, prompt:, transform:, validate:	Read input and store it in the session context
set :field, value	Set a context variable directly from code
persist :field, …, store:	Write named context fields to a BBS::Store
pause "message", seconds:	Display a message and sleep
gate denied: "…" { |ctx| bool }	Halt the flow unless the block returns true
confirm "message", denied: "…"	Yes/no gate — halts on no
confirm "message", denied: "…" { }	Yes/no branch — runs the block on yes, skips on no
menu "prompt", loop: bool { }	Numbered option menu; loops back after each selection when loop: true
exit_menu	Break out of the enclosing menu loop and continue the parent flow

ask options

Option	Description
prompt:	The string printed before the cursor
transform:	A proc applied to the raw input before storing (e.g. transform: :upcase.to_proc)
validate:	A proc that returns true if the value is acceptable; the question is repeated on failure

Banner styles

:success, :info, :error, :warning, :muted — each maps to an ANSI colour.

Menu example

menu ">", loop: true do
  option "Leave feedback" do
    ask :feedback, prompt: "Feedback"
    persist :feedback, store: sessions
    say "Recorded. Thank you.", style: :success
  end

  option "Exit" do
    exit_menu
  end
end

say "Goodbye!", style: :muted

Screens

ERB files in screens/ have access to ANSI colour helpers and a banner helper. Context variables set by ask, set, or passed explicitly to screen are available as @field.

<%= banner("MISSION COMPLETE") %>

  <%= white %>Congratulations!<%= reset %> You are <%= yellow %><%= @name %><%= reset %>.

ANSI helpers

black, red, green, yellow, blue, magenta, cyan, white, reset, bold, dim

Stores

Each persist step writes to a BBS::Store (a thread-safe, append-and-upsert CSV file). session_id and timestamp are always written automatically.

identities = BBS::Store.new(path: 'data/identities.csv', headers: %w[session_id timestamp name code])
signups    = BBS::Store.new(path: 'data/signups.csv',    headers: %w[session_id timestamp email])

persist :name, :code, store: identities
persist :email,       store: signups

Rows are keyed by session_id: the first persist for a session creates the row; subsequent ones update it in place.

Architecture

File	Responsibility
bbs/server.rb	TCP accept loop, spawns one thread per client
bbs/session.rb	Negotiates telnet options, runs the flow
bbs/telnet.rb	Telnet protocol (IAC handling, echo control, readline)
bbs/flow.rb	Flow DSL builder
bbs/flow_runner.rb	Executes a Flow step by step against a session context
bbs/config.rb	Configuration object
bbs/banner.rb	Box-drawing and FIGlet banner renderer
bbs/renderer.rb	ERB screen loader with ANSI colour helpers
bbs/store.rb	Thread-safe CSV persistence