rspec-background-process

RSpec and Cucumber DSL that allows definition of processes with their arguments, working directory, time outs, port numbers etc. and start/stop them during test runs. Processes with same definitions can be pooled and reused between example runs to save time on startup/shutdown. Pooling supports limiting the number of running processes with LRU to limit memory used.

Example Usage

background_process('bin/http-worker').with do |process|
    process.http_port_allocated_form 1200

    process.argument '--listen', '127.0.0.1:<allocated port 1>'
    process.argument '--foreground'
    process.argument '--debug'

    process.ready_when_log_includes 'worker=0 ready'
end
.start
.wait_ready

The above example will start up (or reuse) instance of http-worker process with given arguments and allocated unique port number. The #wait_ready method will return after process logs worker=0 ready to standard output or error. This way the process has a chance of starting up fully before we continue with testing.

Usage with RSpec

Add require 'rspec-background-process' to your spec_helper.rb and use with: :background_process meta tag on example groups that will use #backgroud_process.

require_relative 'spec_helper'

describe 'starting background process', with: :background_process do
    before :all do
        background_process('bin/test_process').with do |process|
            process.ready_when_log_includes 'ready'
        end
        .start
        .wait_ready
    end

    example 'test with process running in background' do
    end
end

Usage with Cucumber

Add require 'rspec-background-process' to your env.rb.

Given /^my server is running$/ do
    @server = background_process('bin/server', load: true).with do |process|
        process.http_port_allocated_form 1200

        process.argument '--listen', '127.0.0.1:<allocated port 1>'
        process.argument '--dump-log-at-exit'
        process.argument '--working-directory', '<working directory>'
        process.argument '--config-prepend', '<project directory>/etc/server.conf'

        process.ready_when_url_response_status 'http://localhost:<allocated port 1>/health.test', 'OK'

        process.refresh_action do |instance|
            open(instance.render('http://127.0.0.1:<allocated port 1>/_purge'))
        end
    end
end

More info

See spec files for more usage options.

Contributing to rspec-background-process