This tutorial will assume that you are running tests from your machine, targeting beta cluster.

You can use the MediaWiki action API for testing, reusing parts of Selenium/Stack, but without Selenium.

Examples will:

Check if a page exists using MediaWiki action API.

Stack

Language	Ruby
Assertion library	RSpec Expectations (ships with RSpec)
Testing framework	RSpec
Mediawiki API	mediawiki_api

Advantages

Simple stack with assertions and testing framework (setup, teardown, reporting...).

Disadvantages

Another tool to learn (testing framework).

Code

require 'mediawiki_api'

RSpec.describe 'Page' do
  before(:all) do
    @client = MediawikiApi::Client.new 'https://en.wikipedia.beta.wmflabs.org/w/api.php'
  end

  it 'Main Page should exist' do
    main_page = @client.action(:query, titles: ['Main Page']).data['pages']
    # => {"1"=>{"pageid"=>1, "ns"=>0, "title"=>"Main Page"}}

    # "1" means the page exists
    expect(main_page['1']).to be_instance_of Hash

    # "-1" means the page does not exist
    expect(main_page['-1']).to be_instance_of NilClass
  end

  it 'Missing Page should not exist' do
    missing_page =
      @client.action(:query, titles: ['Missing Page']).data['pages']
    # => {"-1"=>{"ns"=>0, "title"=>"Missing Page", "missing"=>""}}

    # "1" means the page exists
    expect(missing_page['1']).to be_instance_of NilClass

    # "-1" means the page does not exist
    expect(missing_page['-1']).to be_instance_of Hash
  end
end

Output

Everything is fine.

$ bundle exec rspec spec/api_spec.rb 
..
Finished in 1.78 seconds (files took 0.13949 seconds to load)
2 examples, 0 failures

There is a problem.

$ bundle exec rspec spec/api_spec.rb 
F.

Failures:

  1) Page Main Page should exist
     Failure/Error: expect(main_page['1']).to be_instance_of Hash
       expected nil to be an instance of Hash
     # ./spec/api_spec.rb:14:in `block (2 levels) in <top (required)>'

Finished in 2.43 seconds (files took 0.13955 seconds to load)
2 examples, 1 failure

Failed examples:

rspec ./spec/api_spec.rb:8 # Page Main Page should exist