Minimal project

The smallest complete rubbs project: a board that asks two questions and says whether each answer is right. Four files, nothing optional. Written against rubbs 1.1.0. For everything beyond the minimum, see Getting started.

Files

quiz-bbs/
├── Gemfile
├── bbs.rb
├── Dockerfile
└── compose.yaml

Gemfile

The gem is called bbs and comes from our Git server, not from rubygems.org. The tag pins a release.

source 'https://rubygems.org'

gem 'bbs', git: 'https://git.teletypegames.org/engines/rubbs.git', tag: 'v1.1.0'

bbs.rb

The whole board. ask reads a line into the context under the given name, text writes the block's return value, and when the steps run out the server hangs up.

require 'bbs'

QUESTIONS = {
  'What is 2 + 2?' => '4',
  'Which year did the C64 come out?' => '1982'
}.freeze

BBS.configure do |c|
  c.flow = BBS::Flow.define do
    big_banner 'Quiz BBS'
    QUESTIONS.each_with_index do |(question, answer), i|
      ask :"answer#{i}", prompt: question
      text { |ctx| ctx[:"answer#{i}"] == answer ? 'Correct!' : "Wrong, it is #{answer}." }
    end
    pause 'Bye!', seconds: 2
  end
end

BBS.start

Dockerfile

git fetches the gem, build-base compiles the sqlite3 native extension that rubbs depends on.

FROM ruby:3.3-alpine
RUN apk add --no-cache git build-base
WORKDIR /app
COPY Gemfile ./
RUN bundle install
COPY bbs.rb ./
EXPOSE 2323
CMD ["bundle", "exec", "ruby", "bbs.rb"]

compose.yaml

The board listens on 2323 inside the container; the left side of ports is the port on your machine.

services:
  quiz-bbs:
    build: .
    ports:
      - "2323:2323"
    restart: unless-stopped

Running it

With Docker (Windows, Linux, macOS)

Install Docker: on Windows and macOS Docker Desktop (or OrbStack on macOS), on Linux Docker Engine with the compose plugin. Then, in the project folder:

docker compose up -d --build

Stop it with docker compose down.

Without Docker (Linux, macOS)

Ruby 3.2 or newer, Git and a C compiler are needed.

bundle install
bundle exec ruby bbs.rb

Ctrl-C stops the server. On Windows, use Docker, or run the Linux commands inside WSL.

Calling the board

Any telnet client works; connect to localhost, port 2323.

     ____        _          ____  ____ _____
    / __ \__  __(_)___     / __ )/ __ ) ___/
   / / / / / / / /_  /    / __  / __  \__ \
  / /_/ / /_/ / / / /_   / /_/ / /_/ /__/ /
  \___\_\__,_/_/ /___/  /_____/_____/____/

  What is 2 + 2?: 4
  Correct!
  Which year did the C64 come out?: 1984
  Wrong, it is 1982.

  Bye!

See also

• Getting started — every configuration key, a real board's layout, the production Dockerfile
• Flow — every step of the dialogue DSL
• rubbs — the main page