Lbspec

Lbspec is an RSpec plugin for easy Loadbalancer testing.

Installation

Add this line to your application's Gemfile:

gem 'lbspec'

And then execute:

$ bundle

Or install it yourself as:

$ gem install lbspec

Functions

You can use lbspec to test load balancers.

#transfer

#transfer tests if a virtual host on a load balancer transfer requests to target nodes.

chains

You can use following chains with #transfer.

• port
  • Tests if a virtual host transfers requests to specified port on target nodes.
• tcp
  • Tests with tcp packets for the virtual host.
• udp
  • Tests with udp packets for the virtual host.
• http
  • Tests with an http request for the virtual host.
• https
  • Tests with an https request for the virtual host.
• path
  • Specifies a path for http or https requests.
• from
  • Specifies which host sends to the virtual host.
• options
  • Options which can be used in http or https request commands.
  • You can use options if you configure request commands or capture commands.

Requires

• Users need to be able to login with ssh to the target nodes.
• Users need to be able to sudo on the target nodes.
• netcat and ngrep are needed to be installed.

Limitations

• Lbspec uses only ssh configuration in ~/.ssh/config

Usage

Lbspec is best described by example. First, require lbspec in your spec_helper.rb:

# spec/spec_helper.rb
require 'rspec'
require 'lbspec'

Then, create a spec like this:

require_relative 'spec_helper'

describe 'vhost_a' do
  it { should transfer('node_a') }
end

describe 'vhost_b' do
  it { should transfer(['node_b','node_c']) }
end

describe 'vhost_c:80' do
  it { should transfer(['node_b','node_c']).port(80) }
end

describe 'vhost_c:80' do
  it { should transfer(['node_b','node_c']).port(53).udp }
end

describe 'vhost_c:80' do
  it { should transfer('node_c').http.path('/test/') }
end

describe 'vhost_c:443' do
  it { should transfer(['node_b','node_c']).port(80).https.path('/test/') }
end

describe 'vhost_c:443' do
  it do
    should transfer(['node_b','node_c']).port(80).https.path('/test/')
      .options(ignore_valid_ssl: true)
  end
end

describe 'vhost_c:80' do
  it { should transfer('node_c').http.path('/test/').from('node_a') }
end

How it works

#transfer

1. ssh to nodes
2. cupture probe
3. access with probe
4. judge

Configuration

#transfer

You can change how to capture probes and access to vhost with probes. You can replace default procedures to your procedures in spec_helpers or .spec files as follows. If you use Lbspec::Util.exec_command(), you can specify the node which generate request.

RSpec.configuration.lbspec_capture_command =
  lambda do |port, prove|
  port_str = port > 0 ? "port #{port}" : ''
  "sudo ngrep #{prove} #{port_str} | grep -v \"match:\""
end

RSpec.configuration.lbspec_https_request_command =
  lambda do |addr, port, path, prove|
  uri = 'https://' + "#{addr}:#{port}#{path}?#{prove}"
  Lbspec::Util.exec_command("curl -o /dev/null -sk #{uri}", @request_node)
end

You can also use the procedures with options with a chain options.

RSpec.configuration.lbspec_https_request_command =
  lambda do |addr, port, path, prove|
  opt =  @options[:timeout] ? " -m #{@options[:timeout]}" : ''
  opt << (@options[:ignore_valid_ssl] ? ' -k' : '')
  Lbspec::Util.exec_command("curl -o /dev/null -s #{opt} #{uri}", @request_node)
end

You can replace following items.

• lbspec_capture_command with |port, prove|
• lbspec_udp_request_command with |addr, port, prove|
• lbspec_tcp_request_command with |addr, port, prove|
• lbspec_http_request_command with |addr, port, path, prove|
• lbspec_https_request_command with |addr, port, path, prove|

Contributing

1. Fork it ( http://github.com/otahi/lbspec/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request