Deploying Sinatra Applications to VPS with Passenger/Nginx [Ubuntu 14.04]

Sinatra is a lightweight web development framework (a.k.a micro framework) written in Ruby. It’s a MVC framework (just like Rails) but more suitable for simple and small web projects or APIs (otherwise, you’d probably end up writing too much code, which could be done more easily in Rails, in case of complex web applications).

If you’re new to web development and you’ve just learned ruby then then you should start with sinatra. It’s much easier to learn and you can start creating something (ideally something useful) within hours. Create a simple web app and deploy to Heroku or your VPS using passenger. This article is all about deploying your Sinatra app to VPS.

Why passenger ?

For simple lightweight web applications (sinatra apps), I prefer passenger. You can easily run multiple applications on a single server without any extra configuration (good for small side projects). Later, you can move to unicorn (probably faster response cycle) or puma (lightweight, optimized for concurrency) or something else, if you really need to.

Getting a VPS

Before going through the steps, I assume you’ve already selected a VPS company, if not I would recommend Digital Ocean. (That’s a referral link and you’ll receive $10 credit – worth two months of free hosting) They’ve great plans starting at just $5 per month, well suitable for fun/side projects. For server operating system, select Ubuntu 14.04 LTS, otherwise, you may need to adjust few commands a little, depending on the Linux distribution. For memory and other requirements, 512 MB plan may be enough for a starting out, as you can always upgrade later if required.

Step 1. Server setup

ssh root@SERVER_IP_ADDRESS

Update existing packages and install nano (a lightweight text editor)

apt-get update && apt-get upgrade
apt-get -y install python-software-properties nano

Creating a user

adduser username --ingroup sudo

Now, upload your ssh key (public key) from development machine. (local)

ssh-copy-id username@IP_ADDRESS

Now ssh into the server, and make sure ssh keys are setup as as expected. Additionally, you can turn off password authentication for additional security, type sudo nano /etc/ssh/sshd_config and disable password authentication by changing the value from yes to no. (PasswordAuthentication no)

Note : If you haven’t created any ssh key before (on your local computer), then run ssh-keygen to generate one.

Step 2. Install Ruby

install curl, git and other dependencies

sudo apt-get install git-core curl zlib1g-dev build-essential libssl-dev libreadline-dev libyaml-dev libsqlite3-dev sqlite3 libxml2-dev libxslt1-dev libcurl4-openssl-dev

installing rbenv

git clone git://github.com/sstephenson/rbenv.git .rbenv
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
exec $SHELL

Install ruby 2 and set it as the default

git clone git://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' >> ~/.bashrc
exec $SHELL

rbenv install 2.1.5
rbenv global 2.1.5

Now check if it’s installed correctly

ruby -v

Update gemrc and Install Bundler

echo "gem: --no-ri --no-rdoc" > ~/.gemrc
gem install bundler
rbenv rehash

Step 3. Install nginx and passenger

Adding the passenger repository (official)

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 561F9B9CAC40B2F7
sudo apt-get install apt-transport-https ca-certificates
sudo sh -c "echo 'deb https://oss-binaries.phusionpassenger.com/apt/passenger trusty main' >> /etc/apt/sources.list.d/passenger.list"
sudo chown root: /etc/apt/sources.list.d/passenger.list
sudo chmod 600 /etc/apt/sources.list.d/passenger.list
sudo apt-get update

Install nginx (with extras) and passenger

sudo apt-get install nginx-extras passenger

Step 4. Deployment setup

Setting up nginx and passenger is fairly easy. Just make sure the ruby path is setup correctly in your nginx config. Type which ruby to get the ruby version and make sure that’s correctly specified at /etc/nginx/nginx.conf. (just lookout for the lines that says passenger_ruby)

/etc/nginx/nginx.conf file (make sure it looks like this)

passenger_ruby /home/rkjha/.rbenv/shims/ruby;

Server config for nginx/passenger

sudo nano /etc/nginx/sites-available/example.com

Here is a sample config you can use. Replace example.com and username accordingly. (it also creates a 301 redirect for www version of your domain, you can change that if you want).

Now create a symlink for that config and reload the server to apply the new config.

sudo ln -s /etc/nginx/sites-available/example.com /etc/nginx/sites-enabled/example.com
sudo service nginx reload

Setting up git/bitbucket Add your project to git (if you’ve not done that already), create an account at bitbucket.org And create a repository (private unless you want the source code of your app to be available open/freely) there. You may need to upload the public key (server), go to repo’s settings and Add Deployment key there.

git init
git add --all
git commit -am "first release"
git remote add origin git@bitbucket.org:USERNAME/YOUR-REPO-NAME.git  
git push origin master

If you’ve not used git before then check out some free tutorials listed here and comeback later. Deploy using custom rake task You can use some deployment tools like Capistrano (probably overkill for a Sinatra app) or mina (a lightweight deployment tool). But here, I’ll keep things simple and just use a simple rake task to deploy the code.

Step 5. Deploy

To deploy the app simply type : (you may need to add bundle exec before rake command)

rake deploy:setup
rake deploy

You may also need to run bundle install on server, as the rake task is only fetching the latest files from bitbucket repo. Or you can add few lines there (Rakefile) to do that for you. I’ve tried to keep things as simple as possible or I’ll add that later.

If the deployment is successful you can add a DNS entry for your domain. (Make sure you also add an entry for www, so, the www.example.com will be redirected to example.com, without creating any confusion or duplicate issue in Search Engines)

Note : If you’ve any problem or I missed something, let me know (via comments).

References