Super 8 🎞️

Record and replay ruby-odbc sessions for easier, more accurate testing.

Super 8 is a "vcr"-like library for recording and playing back ODBC interactions made with ruby-odbc, for use with automated testing. More accurate than manually mocking and less work than adding an ODBC-enabled server to your test stack.

Add this line to your application's Gemfile:

gem "super8", github: "johncip/super8", branch: "main"

Then execute:

bundle install

• Ruby 3.1 or higher
• ruby-odbc gem

I haven't tested on lower Ruby versions, but it may work.

• It uses YAML from stdlib, which I think sets hard minimum of 1.8.
• It uses CSV from stdlib, so for Ruby 3.4+ you will need to add gem "csv".

Configure Super8 in your test setup (e.g., spec/spec_helper.rb):

require "super8"

Super8.configure do |config|
  # defaults to "spec/super8_cassettes"
  config.cassette_directory = "spec/super8_cassettes"

  # for writing cassettes, defaults to "utf8"
  config.encoding = "ibm437"
end

Use cassettes in your tests with use_cassette:

RSpec.describe "ODBC stuff" do
  it "queries the database" do
    Super8.use_cassette("users/all", mode: :playback) do
      db = ODBC.connect("dsn")
      result = db.run("SELECT * FROM users")
    end
  end
end

Modes:

• :record - Records ODBC interactions to a cassette file
• :playback - Replays recorded interactions without connecting to the database

Currently supported ODBC methods:

• ODBC : .connect
• ODBC::Database: #run
• ODBC::Statement: #columns, #fetch_all, #drop, #cancel, #close

I wrote and maintain an application that communicates with the Retalix ERP. I use ruby-odbc to connect to the instance and incrementally sync a number of tables.

In testing, I would stub the ODBC parts out, which was low-level and noisy. It also meant I had to check the queries for regressions manually.

vcr is a library for "recording" HTTP API requests, so that they can be accurately mocked in ruby tests. It stores the request as well as the response, so that if the request made changes, it can be considered a test failure. It's also very easy to record "cassettes." I've wanted something like that for for ODBC.

This project was developed with AI assistance as an experiment in improving and documenting my workflow. The process and decisions are documented in the design directory.

• Design docs
• Copilot chat logs
• Architecture decision records

The gem is available as open source under the terms of the MIT License.