cambridge-healthcare / hi_sinatra-docker

Sinatra app ready to be run as a docker container, including Vagrant setup

We have been using Docker in our staging environment for a month now and are planning to make it part of our production setup once the first stable version gets released.

Whenever a new github branch gets started, Jenkins, our Continuous Integration server, automatically attempts to build a new Docker container from it. If all tests pass, this container becomes available on our office network and we receive a Campfire notification. If tests fail, we leave a Docker image for our engineers to examine. For Service Oriented Architectures (SOA), this approach saves a lot of time when working on features that span multiple services and cannot be isolated to a particular component. The extra confidence that we get from integrating features at a platform level means that we are more effective and don't need to wait on one another.

We couldn't find any clear guide on integrating Docker with Jenkins so we've decided to contribute one. We have included a Vagrantfile which automates the entire setup except creating Jenkins jobs.

1. Install VirtualBox, Vagrant & git

Either install using your package manager or use the official downloads:

• install virtualbox
• install vagrant
• install git

2. Create Vagrant VM

The Vagrantfile will get everything setup for you. Cloning the repository and running vagrant up inside it will create a VM with the latest stable Docker and Jenkins services running side-by-side.

There will also be a running version of hi_sinatra inside a Docker container using a Redis server running in a separate container for tracking requests. Use the IP address and port displayed at the end of the Vagrant run to access the hi_sinatra app in your browser.

git clone https://github.com/cambridge-healthcare/hi_sinatra-docker.git
cd hi_sinatra-docker
vagrant up

3. Setup Jenkins job

As the jenkins user belongs to the docker group, it can run Docker commands directly. Combined with Dockerize, setting a job that integrates with Docker couldn't be easier:

| Job name | hi_sinatra                          |
| Job type | Build a free-style software project |
| Build    | Execute shell                       |

This is the shell command which you will need to use for the build execution:

/bin/bash -c "source $HOME/.profile && dockerize boot cambridge-healthcare/hi_sinatra-docker hi_sinatra"

Every successful Jenkins build will now result in a Docker container running hi_sinatra and a Redis server container for each git branch.

4. Successful build results in a running Docker container

Building the project for the first time (truncated output):

Building in workspace /home/jenkins/.jenkins/workspace/hi_sinatra
[hi_sinatra] $ /bin/sh -xe /tmp/hudson8824124682277145403.sh
+ /bin/bash -c source /home/jenkins/.profile && dockerize boot cambridge-healthcare/hi_sinatra-docker hi_sinatra
HEAD is now at b054795... @dawson ready for review
Uploading context 528384 bytes
Uploading context 1085440 bytes
Uploading context 1611776 bytes
Uploading context 2162688 bytes
Uploading context 2334720 bytes

Step 1 : FROM howareyou/ruby:2.0.0-p247
 ---> b712db79101d
Step 2 : ADD ./ /var/apps/hi_sinatra
 ---> 442707553694
Step 3 : RUN . /.profile ;  rm -fr /var/apps/hi_sinatra/.git ;  cd /var/apps/hi_sinatra ;  bundle install --local ;# END RUN
 ---> Running in 747a7653af9f
Installing diff-lcs (1.2.4) 
Installing rack (1.5.2) 
Installing rack-protection (1.5.0) 
Installing rack-test (0.6.2) 
Installing redis (3.0.5) 
Installing rspec-core (2.14.5) 
Installing rspec-expectations (2.14.3) 
Installing rspec-mocks (2.14.3) 
Installing rspec (2.14.1) 
Installing tilt (1.4.1) 
Installing sinatra (1.4.3) 
Using bundler (1.3.5) 
Updating files in vendor/cache
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.
 ---> 5439e797487a
Step 4 : CMD . /.profile && cd /var/apps/hi_sinatra && bin/test && bin/boot
 ---> Running in 8282ba047a40
 ---> 1cf5ae0c0cbc
Step 5 : EXPOSE 8000
 ---> Running in 54b5a5d26b28
 ---> 0d07513f4e63
Successfully built 0d07513f4e63
Removing intermediate container b4a2da6aa89a
Removing intermediate container 747a7653af9f
Removing intermediate container 8282ba047a40
Removing intermediate container 54b5a5d26b28
Uploading context 557056 bytes
Uploading context 1114112 bytes
Uploading context 1660928 bytes
Uploading context 2217984 bytes
Uploading context 2334720 bytes

Step 1 : FROM hi_sinatra:master
 ---> 0d07513f4e63
Step 2 : ADD ./ /var/apps/hi_sinatra
 ---> 8fd588d1629b
Step 3 : RUN . /.profile ;  rm -fr /var/apps/hi_sinatra/.git ;  cd /var/apps/hi_sinatra ;  bundle install --local ;# END RUN
 ---> Running in bebf708f0c8a
Using diff-lcs (1.2.4) 
Using rack (1.5.2) 
Using rack-protection (1.5.0) 
Using rack-test (0.6.2) 
Using redis (3.0.5) 
Using rspec-core (2.14.5) 
Using rspec-expectations (2.14.3) 
Using rspec-mocks (2.14.3) 
Using rspec (2.14.1) 
Using tilt (1.4.1) 
Using sinatra (1.4.3) 
Using bundler (1.3.5) 
Updating files in vendor/cache
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.
 ---> 1b91e7998014
Step 4 : CMD . /.profile && cd /var/apps/hi_sinatra && bin/test && bin/boot
 ---> Running in 28987e90ee13
 ---> f16d718c59d5
Step 5 : EXPOSE 8000
 ---> Running in b540dec6a80a
 ---> f7980a764c57
Successfully built f7980a764c57
Removing intermediate container 2e8635a04a6e
Removing intermediate container bebf708f0c8a
Removing intermediate container 28987e90ee13
Removing intermediate container b540dec6a80a
c21ec0d7c419
293ffdc2e66c
Finished: SUCCESS

While the first build takes 2 mins and 26 secs, the second one takes a mere 5 secs. That is 5 seconds to install all the ruby gems, run all the tests, build a Docker image and start a new Docker container that makes that app version available for further testing (eg. integration tests, stress tests). The resulting app image is a mere 12.29kB. That's the only new content which needs deploying into production.

github service hooks

For integrating github with a Jenkins server not accessible from the outside world, we have found Amazon SQS to be an elegant solution. There is a Github SQS plugin that is installable from within Jenkins, setup is straightforward.

The only gotcha is that the SQS must be setup in the us-east-1 region. We had set it up initially in eu-west-1 and were puzzled as to why it wasn't working.

"How are you?" base Docker images

During our use of Docker, we have made public a few Docker images on the public Docker index. The app which we have given as an example makes use of howareyou/ruby_2.0.0-p247 and all its dependencies.

If you have found this tutorial useful, please help us to improve it by adding your contributions via pull requests.

hi_sinatra-docker's Issues

no longer working (?)

Hi, tried running this from your blog post http://blog.howareyou.com/post/62157486858/continuous-delivery-with-docker-and-jenkins-part

Used current pieces VirtualBox-4.3.28-100309-Win.exe, Oracle_VM_VirtualBox_Extension_Pack-4.3.28-100309.vbox-extpack, vagrant_1.7.2.msi, Git-1.9.5-preview20150319.exe

This is what happened:

Bringing machine 'default' up with 'virtualbox' provider...
==> default: Box 'ubuntu' could not be found. Attempting to find and install...
default: Box Provider: virtualbox
default: Box Version: >= 0
==> default: Adding box 'ubuntu' (v0) for provider: virtualbox
default: Downloading: http://files.vagrantup.com/precise64.box
default: Progress: 100% (Rate: 577k/s, Estimated time remaining: --:--:--)
==> default: Successfully added box 'ubuntu' (v0) for 'virtualbox'!
==> default: Importing base box 'ubuntu'...
==> default: Matching MAC address for NAT networking...
==> default: Setting the name of the VM: hi_sinatra-docker_default_1434409184461_11936
==> default: Clearing any previously set network interfaces...
==> default: Preparing network interfaces based on configuration...
default: Adapter 1: nat
default: Adapter 2: hostonly
default: Adapter 3: hostonly
default: Adapter 4: hostonly
default: Adapter 5: hostonly
default: Adapter 6: hostonly
default: Adapter 7: hostonly
default: Adapter 8: hostonly
default: Adapter 9: hostonly
There was an error while executing VBoxManage, a CLI used by Vagrant
for controlling VirtualBox. The command and stderr is shown below.

Command: ["modifyvm", "928e9c53-0b37-4d63-9d33-33623337ea8f", "--nic1", "nat", "--nic2", "hostonly",
"--hostonlyadapter2", "VirtualBox Host-Only Ethernet Adapter #2", "--cableconnected2", "on", "--nic
3", "hostonly", "--hostonlyadapter3", "VirtualBox Host-Only Ethernet Adapter #2", "--cableconnected3
", "on", "--nic4", "hostonly", "--hostonlyadapter4", "VirtualBox Host-Only Ethernet Adapter #2", "--
cableconnected4", "on", "--nic5", "hostonly", "--hostonlyadapter5", "VirtualBox Host-Only Ethernet A
dapter #2", "--cableconnected5", "on", "--nic6", "hostonly", "--hostonlyadapter6", "VirtualBox Host-
Only Ethernet Adapter #2", "--cableconnected6", "on", "--nic7", "hostonly", "--hostonlyadapter7", "V
irtualBox Host-Only Ethernet Adapter #2", "--cableconnected7", "on", "--nic8", "hostonly", "--hoston
lyadapter8", "VirtualBox Host-Only Ethernet Adapter #2", "--cableconnected8", "on", "--nic9", "hosto
nly", "--hostonlyadapter9", "VirtualBox Host-Only Ethernet Adapter #2", "--cableconnected9", "on"]

Stderr: VBoxManage.exe: error: Invalid NIC number 9
VBoxManage.exe: error: Invalid NIC number 9
VBoxManage.exe: error: Invalid NIC number 9

Should this Vagrantfile expose port 8080?

Other Vagrant VMs expose ports to the host OS. I added the following to access the Jenkins UI:

config.vm.forward_port 8080, 8080