There are some wonderful CI / CD tools out there right now, and some of them have very usable free tiers. A few good examples include Shippable, Wercker, CloudBees, and Snap-CI. There are others, of course, but these all allow at least one private project to get started.

I have recently moved my projects to Snap, and my hack for the day needed to be deployed to OpenShift. Although Snap has built in integrations for some providers, no such integration currently exists for OpenShift (yet!). However, it takes less than 10 minutes to configure a Deploy step to OpenShift, and here’s how.

Add SSH Keys
You will need to add your private SSH key (i.e. id_rsa) to Snap, and your public key to OpenShift (i.e. id_rsa.pub)

You can create the keys on another machine with the ssh-keygen command, and copy them into them into the corresponding places. In OpenShift, this is under Settings -> Add a new key. Once open, paste in the contents of your id_rsa.pub key

In Snap, edit your configuration, navigate to your Deploy step, and look for “Secure Files” and “Add new”

Get the content of the id_rsa key you generated earlier and post it in the content box. It should look like this, with “/var/go” as the file location, except with a real key:

Enable Git Push from Snap

If you’ve used ssh much, you are probably aware that that you can specify an identify file with the “-i” flag. The git command has no such flag, yet, but we can create a simple bash script that emulates this (script courtesy of Alvin Abad).

Add another New File in Snap and paste in the below script:

#!/bin/bash
 
# The MIT License (MIT)
# Copyright (c) 2013 Alvin Abad
 
if [ $# -eq 0 ]; then
    echo "Git wrapper script that can specify an ssh-key file
Usage:
    git.sh -i ssh-key-file git-command
    "
    exit 1
fi
 
# remove temporary file on exit
trap 'rm -f /tmp/.git_ssh.$$' 0
 
if [ "$1" = "-i" ]; then
    SSH_KEY=$2; shift; shift
    echo "ssh -i $SSH_KEY \$@" > /tmp/.git_ssh.$$
    chmod +x /tmp/.git_ssh.$$
    export GIT_SSH=/tmp/.git_ssh.$$
fi
 
# in case the git command is repeated
[ "$1" = "git" ] && shift
 
# Run the git command
git "$@"

Give this script the name “git.sh”, set the file permissions to “0755”, and update the file location to “/var/go”.

Profit
With all these parts configured correctly you can add this single line to your Deploy script:

/var/go/git.sh -i /var/go/id_rsa push ssh://[email protected]/~/git/example.git/

Re-run the build, check your logs, and it should deploy. Good luck!

I first used Splunk about 10 years ago after an old colleague installed it on a computer in the corner, and ever since then I have preached about it. If you have log data, of any kind, I’d recommend you give it a go.

The Splunk people have a a few pretty good options for trying Splunk out, as you can either use Splunk Storm or Splunk Free. The first option is obviously hosted, and has a generous storage option, but also does not allow long term storage of data. I send system log data to Splunk Storm.

However, what if you don’t have a lot of data, but you want to keep that data forever? After reading Ed Hunsinger’s Go Splunk Yourself entry about using it for Quantified Self data, I knew I had to do the same.

From personal experience, Splunk requires at least 1GB to even start. You can probably get it to run on less, but I haven’t had much success. This leaves two options: look at Low End Box for a VPS with enough memory (as cheap as $5/month), of use OpenShift. Red Hat generously provides three “gears” to host applications, for free, and each with 1GB of memory. I have sort of a love-hate relationship with OpenShift, maybe a bit like using OAuth. Red Hat calls OpenShift the “Open Hybrid Cloud Application Platform”, and I can attest that it is really this. They have provided a method to bundle an application stack and push it into production without needing to fuss about infrastructure, or even provisioning and management of the application. It feels like what would happen if Google App Engine and Amazon’s EC2 had a child. Heroku or dotCloud might be its closest alternatives.

Anyways, this isn’t a review of OpenShift, although it would be a positive review, but instead on how to use OpenShift to host Splunk. I first installed Splunk in a gear using Nginx as a proxy, and it worked. However, this felt overly complex, and after one of my colleagues started working on installing Splunk in a cartridge, I eventually agreed this would be the way to go. The result was a Splunk cartridge that can be installed inside any existing gear. Here are the instructions; you need an OpenShift account, obviously. The install should take less than ten clicks of your mouse, and one copy/paste.

From the cartridge’s GitHub README:

1. Create an Application based on existing web framework. If in doubt, just pick “Do-It-Yourself 0.1” or “Python 2.7”
2. Click on “Continue to the application overview page.”
3. On the Application page, click on “Or, see the entire list of cartridges you can add”.
4. Under “Install your own cartridge” enter the following URL: https://raw.github.com/kelvinn/openshift-splunk-cartridge/master/metadata/manifest.yml
5. Next and Add Cartrdige. Wait a few minutes for Splunk to download and install.
6. Logon to Splunk at: https://your-app.rhcloud.com/ui

More details can be read on the cartridge’s GitHub page, and I would especially direct you to the limitations of this configuration. This will all stop working if Splunk makes the installer file unavailable, but I will deal with that when the time comes. Feel free to alert me if this happens.