This document details a testing framework utilizing Docker containers for shipping and verifying software packages, specifically focusing on the Snap telemetry service. It outlines the setup of testing environments using Serverspec for validation of packages, commands, and configurations within Docker containers. Additionally, it discusses the pros and cons of various testing strategies and tools, as well as scheduling for future Docker meetups.

1. Trust, but verify
Testing with Docker Containers

2. whoami
● Nan Liu

3. Ship Faster

4. Snap Container
FROM alpine:3.4
MAINTAINER Nan Liu
ENV SNAP_LOG_LEVEL
EXPOSE 8181
ADD build/snapteld /opt/snap/sbin/snapteld
ADD build/snaptel /opt/snap/sbin/snaptel
COPY snapteld.conf /etc/snap/snapteld.conf
CMD /opt/snap/sbin/snapteld -t 0 -l 1 -o ''

5. Snap Container
Just it.

6. Fail
dynamically linked (uses shared libs), not stripped

7. Serverspec
require "serverspec"
set :backend, (ssh/exec/cmd/...)
describe :label do
describe :resource_type("name") do
it { should be_assertions }
end
end
System
Vagrant
Ubuntu VM
Windows VM
Serverspec
Remote System

8. Verify
describe package("snap-telemetry") do
it { should be_installed }
end
describe command("ldd $(which snapteld)") do
its(:stdout) { should match /not a dynamic executable/ }
end
* serverspec in vagrant

9. Container Inspection

10. Docker Serverspec
require 'serverspec'
require 'dockerspec/serverspec'
describe docker_build(path: './Dockerfile') do # erb, string
# test
end
describe docker_run('intelsdi/snap:xenial', family: 'debian')
#test
end

11. Docker Serverspec
describe docker_build("alpine/.") do
it { should have_maintainer /Nan Liu/ }
%w[SNAP_VERSION SNAP_TRUST_LEVEL SNAP_LOG_LEVEL].each do |e|
it { should have_env e }
end
it { should have_label( "license" => "Apache 2.0" ) }
it { should have_expose '8181' }
end

12. Docker Serverspec
describe docker_build("alpine/.") do
describe docker_run(described_image) do
describe file('/etc/snap/snapteld.conf') do
its(:content_as_yaml) {
should include('log_path' => '/var/log/snap')
should include('control' => {
"auto_discover_path" => "/opt/snap/plugins"})
}
end
end

13. Demo

14. Travis CI
sudo: true
services:
- docker
language: ruby
before_deploy:
- docker login -e="$DOCKER_EMAIL" -u="$DOCKER_USERNAME"
-p="$DOCKER_PASSWORD"

15. Travis CI
deploy:
provider: script
script: docker push intelsdi/snap:latest
on:
branch: master

16. Mission Accomplished

17. Testing Snap
● Operating systems
○ Linux: RedHat/Ubuntu
○ MacOS
● 85 Plugins
○ Databases/NoSQL
○ OpenStack
● ^^^ * Snap Version * Plugin Versions = ???

18. Engineer view

19. User view

20. Large Test Goals
● Matrix of Snap/Snap plugin versions
● Support multiple OS versions
● Small overhead/footprint +
● Debugging tool +

21. Large Test
Pros
● simple?
Cons
● script sprawl
● parsing output (jq)
● dockerfile proliferation
● no os abstraction
System
Docker
Snap
Dependency
#!/bin/bash
● launch containers
● run scripts in containers
● cleanup
#!/bin/bash
test scripts

22. Large Test
Pros
● Testing framework
Cons
● snowflake containers
● dockerfile proliferation
System
Docker
Snap
Dependency
#!/bin/bash
● launch containers
● run scripts in containers
● cleanup
#!/bin/env python
goss test framework

23. Large Test
Pros
● all in one
Cons
● ruby dependency
● need to learn serverspec
System
Docker
Snap
Dependency
docker serverspec
● build containers
● docker exec commands
● cleanup

24. Docker Compose
services:
snap:
image: intelsdi/snap:${OS}_test
environment:
SNAP_VERSION: "${SNAP_VERSION}"
volumes:
- "${PLUGIN_PATH}:/plugin""

25. Docker Compose Serverspec
describe docker_compose("../docker-compose.yml") do
its_container(:snap) do
describe command("snaptel task create -t /plugin/examples/tasks/#{t}")
do
its(:exit_status) { should eq 0 }
end
end
end

26. Large Test
System
Docker
Snap
Dependency
docker-compose-serverspec
● build containers
● docker exec
commands
● cleanup

27. Docker-inception (sibling containers)
docker run -v /var/run/docker.sock:/var/run/docker.sock
-v "${proj_dir}":/plugin
-e PLUGIN_PATH="${proj_dir}"
-e SNAP_VERSION="${SNAP_VERSION}"
-e OS="${OS}"
-it intelsdi/serverspec:alpine
/bin/sh -c "cd /plugin/scripts && rspec ./test/*_spec.rb"

28. Docker Compose Serverspec
describe docker_compose("../docker-compose.yml") do
its_container(:snap) do
describe command("snaptel task create -t /plugin/examples/tasks/#{t}")
do
its(:exit_status) { should eq 0 }
end
end
end

29. Large Test
its_container(:influxdb) do
describe 'wait for influxdb service' do
it do
c=cmd_retry('curl -sl -I localhost:8086/ping')
expect(c.exit_status).to eq 0
end
end
end
System
Docker
Snap
Influxdb
docker-serverspec
● build containers
● docker exec
commands
● cleanup

30. Large Test
describe command("#{snaptel} plugin list") do
it { load_all_plugins }
its(:exit_status) { should eq 0 }
its(:stdout) {
plugins.each do |p|
_ , name = p
should contain(/#{name}/)
end
}
end

31. Demo

32. Large Test
Cons
● Docker environment variable nesting
● pry debug output munged
System
Docker
Snap
Dependency
docker-serverspec
● build containers
● docker exec
commands
● cleanup

33. Ship Faster with
Confidence

34. Questions?
● serverspec.org
● github.com/zuazo/dockerspec
● github.com/nanliu/docker-serverspec
● github.com/intelsdi-x/snap

35. Next Docker Meetup
● Feb 9th @ Puppet Labs
● Mike Coleman | Docker