RoR Server Construction and Capistrano Support - ruby-on-rails

I have been creating a website with Ruby on Rails, and will be hosting it through a friend. He has the space and capacity to host the server, and I have a system to devote to being a dedicated server. And this is my first attempt at a Rails website, plus self-hosting with a friend.
I will be formatting and preparing the server today and tomorrow with the following software configuration:
Apache2
Phusion Passenger (aka, mod_rails)
Ruby Enterprise Edition
MySQL 5
I do have a number of questions, and I apologize for their complexity. I haven't found a guide for this configuration yet, and being new to Rails I haven't the experience to navigate my way through this yet.
What build of Linux is most recommended for this configuration?
I have been planning to deploy on CentOS. The caveat is that I have been a Windows user since my early days, and have only used Linux as a webhost and very few development commands (such as CVS). Thus my knowledge of Linux is rather small, and my experience smaller. If I run into any deployment snags, technicalities thanks to the distro of Linux, or anything of the sort ... I'm totally hung out to dry.
This includes things like building anything from source code.
How do I set up Capistrano on my server for remote deployment?
I know this is an oxymoron (Capistrano is client-side, not server-side) but I don't know what it needs on the server. Does it need FTP? SFTP? SSL? SSH? What?
What do I configure on my server, and how do I configure it, to enable Capistrano to run smoothly?
Also, how do I refer Capistrano to the fact that my SCM is on localhost and is by Mercurial? (I used TortoiseMg.) I could convert to SVN and probably set up a repository on the server, but I'm not entirely sure how to do that.
What is the biggest snag you watch for when deploying from a localhost development, to deployment on a totally different OS?
Miscellaneous
Why not deploy to Windows then? Because I'm footing the bill, and I don't want to pay for another copy of XP or possibly 2000; I refuse to use Vista. Plus, Linux is much more secure than Windows for a server environment.
Why not read the existing guides? I am; this is my first site with Ruby on Rails, my budget is in the less than double-digits area now, and I'm trying to expand my horizons by doing the server configuration and the remote deployment (for further development of the site) by myself. I've relied on hosts in the past for my PHP websites, but they're much more homogeneous in their configuration. Ruby servers are expensive, prohibitively so for me, and to learn its configuration wouldn't hurt to know.

What build of Linux is most recommended for this configuration?
Any of the distributions will work fine as long as they can run Apache2 (which is almost all of them) and you can install Passenger (along with ruby and rails).
I personally use CentOS and find its package manger to be ridiculously easy to use (yum).
yum install -y httpd ruby
gem install rails passenger
Then all you have to do is a little configuration in /etc/httpd/conf/httpd.conf to add Passenger (following the install file for Passenger passenger-install-apache2-module) and point it to your deployment folder .../app_name/current/public.
Since you are using Passenger you should override the restart task to work for it.
config/deploy.rb
namespace :deploy do
desc "Restart Application"
task :restart, :roles => :app do
run "touch #{current_path}/tmp/restart.txt"
end
end
How do I set up Capistrano on my server for remote deployment?
All Capistrano needs is SSH access with sufficient permissions to deploy, migrate, restart app server, etc. Just follow the getting started guide at the Capistrano website and you will be up and running in no time.
Capistrano needs access to your SCM, you will need to allow it to connect to your machine. All Capistrano does is checkout your code into a release folder and moves the symbolic link from the old version and restarts your app server.
What is the biggest snag you watch for when deploying from a localhost development, to deployment on a totally different OS?
The biggest snag is with migrations, test, test, test, and test them some more. A bug in your application is easy to fix and redeploy, but a bug in your migration could end up a huge pain in the ass with the possibility of data loss.

I've found the articles posted at Slicehost.com (a VPS hosting company) to be pretty helpful.
The full list of articles are at: http://articles.slicehost.com/sitemap . You'll find a number of articles there related to production deployment of a Ruby on Rails application.

I recommend using Ubuntu server and deprec, as it provides a ton of sysadmin recipes that make things even easier.

Related

Rails Production Environment

I'm new to rails have been searching for deployment guides on the web - it's quite fragmented. I see some which recommend deploying as a sudo enabled user. I was thinking you would create a user with no sudo powers to run the app for security reasons. It would need it's own home directory for RVM and bundler but having sudo powers seems redundant and a security risk. I'm doing this all manually as it's a tricky beta level application and deploying it is not yet straightforward, so capistrano would only be a layer of obfuscation at this point.
I'm using thin as the server with Nginx as the proxy and redis and Postgres as the database. Clockwork and sidekiq as well.
Capistrano seems like a lot of work even for a small project but it's worth getting setup anyway if you have hopes of the application growing (and thus the complexity of deployment increasing).
I personally like the idea of separating the distribution specific Ruby available (and gems) to an RVM deployment specific to the application. Furthermore, requiring bundler to manage gem dependencies and ensuring compliance is invaluable. I wouldn't suggest enabling sudo for that user; it'll expose the whole stack from HTTP requests to root level OS control. Applications shouldn't require administrative access, deployment scripts might.
If you're new to Rails I'd recommend something simple for your first deployment. Heroku allows you to deploy apps by simply doing a git push to their repository. They handle all the steps necessary to make your app available on the Internet. Best of all it's free as long as you don't need heavy resources.
EngineYard is another hosting solution that's easy to deploy to and step up from Heroku in terms of flexibility (and cost).
Once you're comfortable with deploying production apps then you can look to using your own servers and using capistrano for the ultimate in customization.
I have production websites running in both environments and I've yet to need to go to the trouble of migrating to my own hosted server.

What, where and how to upload Ruby on Rails application files to the VPS?

I am using Ruby on Rails 3.0.9 and I would like to publish my web site. I already set my VPS running Ubuntu 10.04 LTS and the capistrano gem (this one I think as well as possible). Now, what I need to do is to upload all files to the www/project_name directory (I am on Mac OS)...
What I have to do to accomplish that?
You don't need your deployment machine to have Capistrano. Capistrano automates a bunch of tasks that I suggest you do at least one manually so you know what's going on. Sooner or later, you'll be debugging some Capistrano task, so you may as well figure out the guts sooner or later.
Coarsely, what you need to do is to basically duplicate your development environment on your production machine. If you have it on version control, you can git clone or svn whateveritis on your production machine. If not, you can scp it over with scp /local/rails/dir remoteuser#remotehost:www/projectname.
At this point, you should actually do the remainder of the work on the server. Since you've managed to install Capistrano, I assume you're familiar with the basics of making your way around SSH.
Once the code's over, you have to install the prerequisites. If you're using 3.0.9 you should be able to run bundle install --deployment, where the deployment flag basically tells bundler to use the identical gem set as on your development machine.
When that's done, actually getting the server online will vary based on your setup. If you're using non-standalone passenger, just follow any of the many guides at this point. If you're running standalone passenger or thin or unicorn or any other standalone rails server, go ahead and start that in daemon mode (so it won't quit on you when you end your SSH session) and make sure you se the production flag. You can either start it in sudo and have it listen on port 80 (e.g., sudo thin start -d -p 80) or have it listen on a higher-number port and use a reverse proxy on your WWW-facing server. The instructions for how to reverse proxy are all over the internet.
Let me know if you have any questions.
You have half of a deployment solution with Capistrano. Commonly Passenger is used as the other half, which sits on the server and loads your app. To accomplish this, usually, SSH keys are used. There are numerous tutorials on how to set this up. One of my favorites written by Dan Benjamin can be found on his blog Hivelogic.
Edited to provide more begginer info:
Capistrano begginer's guide from the Capistrano wiki.
Passenger Stand Alone Guide from the Passenger website.
Be sure to check out the other guides for the webserver of your choice when you're ready.
These guides will give you the background you need to get a local Passenger & Capistrano deployment going. These guides provide the knowledge you need to get achieve what you want.
Simple and short sample of deployment via SSH http://alexeypetrushin.github.com/vfs/ssh_deployment.html

Is there a linode version of EC2 on Rails?

We really like the idea of hosting with Amazon EC2 and the excellent EC2 on Rails, but our cashflow isn't enough to justify a move to EC2. So we've decided to host with linode. Now we're trying to put together the best Rails server build.
For those that don't know, EC2 on Rails is an opinionated Ubuntu Linux Server image for Amazon's EC2 hosting service. Out of the box, it runs a standard Ruby on Rails application with little to no customization.
So, is there something like EC2 on Rails for linode?
We'd need at least the following:
Ruby 1.8.7
Ruby on Rails 2.3.8
MySQL 5
memcached
Automatically runs hourly, daily, weekly and monthly scripts if they exist in Rails application’s script directory
Local Postfix SMTP mail server
SSL support
Passenger + Ngnix or Mongrel + Apache
32 bit image Ubuntu
With a railsy setup, meaning fast and simple. So, anyone run across anything like EC2 on Rails, but for linode?
I have been using linode for my personal use for a while and I think no matter what, you are probably going to have to get your hands dirty. I kind of like it for exactly that reason, but that is just my taste. They do have stack scripts with some predefined setups. The closest I can find to what you are looking for is a ruby/apache/mysql script that is fairly customizable.
From the script:
Installs a fully functioning, ready to
go stack that's optimized specifically
for your Linode's resources. By
default, it creates a VirtualHost
using the reverse DNS of your Linode's
primary IP.
This installs a stack based on Ruby,
Apache, and MySQL. This also gives you
the options to install gems so that
you can be up and running Ruby on
Rails in no time.
Optionally creates a MySQL database
and user, and assigns that user grants
to the database.
You may use this as an example for
creating more VirtualHosts. Set up
VirtualHosts, install your sites,
point your domains to your Linode, and
you're set!
This script downloads and compiles the
source from Ruby's ftp. Along with
Ruby, the latest version of ruby gems
is installed and you have a choice of
initial gems to install. Rails and
passenger can be used to have a ready
to go Rails server. Once this script
has finished be sure to run
'passenger-install-apache2-module' to
complete the passenger install.
Note that this script may take 1.5 - 2
hrs depending on the gems that are
specified.
All details of this stack script are
logged to /root/log.txt and the stack
script is finish when the line
"StackScript Finished!" is written to
the log file.
You might have good luck talking to their support though, they might have some more secret sauce that I haven't found yet.
Nothing in that setup sounds EC2-specific beyond the name. It appears it is just convenient to use with EC2, because they let you grab a disk image from another account.
You are welcome to create your own StackScript to do this and contribute it to the community. Once a StackScript is written, it can be marked public and used by others. EC2 on Rails has a public GitHub repository from which you can get started, and honestly, I'd love to see things like this ported to the StackScript system.

How do you deploy your Rails application?

Do you upload your rail application to your host via FTP first?
I'm currently using Passenger and Capistrano. If I do "cap deploy" in my local machine then I think Capistrano should upload my rail application to my host, right?
Someone from my host is saying that I need to run "cap deploy" in server. I think it doesn't make sense.
You should be able to run cap deloy on your local machine and that should get the current version of your software to the server. However, you need to set up first how this is supposed to happen. I for example use Git to manage my code and also use it to get my software on the server. However, you could also use SVN or FTP if you prefer that. If you google for Capistrano together with the Software youbeant to transfer the code with and maybe even your hosting providers name, you probably will find a decent step by step explanation. For me John Numemaker's post on deploying with Capistrano and Git on Dreamhost really helped: http://railstips.org/blog/archives/2008/12/14/deploying-rails-on-dreamhost-with-passenger/
As an alternative you also might want to check out heroku.com. Their smallest offer is free and enough for most projects. The deployment process is so easy a monkey could deploy a Rails app on their platform. I generally can only recommend heroku.

Why is it supposedly "hard" to deploy Ruby on Rails to production?

I admit that I don't follow much of anything "right" on deploying test versus production code. I have been using ASP.NET, and I typically run it locally in Visual Studio, it works, I upload it, I test it again on the production server.
I have read several people say that deploying Rails apps is harder and there are special programs/ways on the ruby site about deploying RoR. I've only toyed with RoR. What is special about deployment? You don't just copy and paste the code and run it (from development machine to the production)? Is it because one is in Apache and the other running on the built in server?
This will be on a Mac Server if it matters.
Deploying RoR is not difficult anymore, especially with Phusion Passenger.
What is somewhat difficult, is getting a automated production environment setup with capistrano, vlad, etc. If you don't mind simply copying your code to the server, you can do that just fine. Most people choose not to do it that way because you lose out on a lot of the benefits that the automated deployment tools give you.
I guess people consider a Rails app harder to deploy than say some PHP apps or such where you just plop the code somewhere and point Apache or whatever at it. But, as mentioned above, you could do that now with Phusion Passenger.
We use Nginx+Passenger, but not for simplicity of deployment. Capistrano is our deploy tool of choice, and really, unless you have a very simple app, you're going to want something like Capistrano anyway. For example, with our deploy, we do a slew of things:
run any database migrations
generate release notes automatically, based on all the commits to Git between the last deploy and this one
notify various people via email (with differing lists depending on whether the deploy is to our staging environment or production) - we do this via cap_gun which integrates with Capistrano.
Notify New Relic RPM of the deploy so it can mark it in our RPM analysis
Notify Hoptoad of the deploy, so it too can have that data when reporting any exceptions
produce our sitemap.xml file, and ping Google to tell them there's a new one
update crontab files (I store our crontab files for each server in our git repo, and then on deploy it sees if there is a new version and updates accordingly, etc.).
flush/restart memcached
There are other ways aside from Capistrano, but it's a proven tool, with a lot of flexibility, yet pretty simple to setup a vanilla configuration.
So, my take is that once you get into any app that is beyond just the very simplest of apps, you're going to need/want to be doing things other than just simply updating the code. In the beginning though, if you just need the code updates, and maybe Rails migrations, then you can do simpler things like Passenger and code sync, or look at tools like Heroku or Engine Yard's stuff where they do a deploy by doing a Git clone (and then offer some additional abilities).
Another super easy way to deploy is with http://heroku.com/
Some of the issues you face with deploying rails to production:
Database connection.
You need to be sure that the database connector is set up for the production environment.
Database migrations.
You have to run database migrations against the production database even though you may have already run them in production/testing/staging
Ruby version. The version or sub-version or Ruby can trip you up, e.g. An error occurred while installing debugger-linecache (1.1.1), and Bundler cannot continue
Gem dependency.
Your production environment may have different packages and gems from development. Bundler will figure this out for the most part and install the dependencies but occasionally there are still issues that you have to resolve manually.
Dependencies.
Some gems on some machine have particular dependencies. I have seen frequent problems with using gems on my unix box that work on OSX and vice-versa.
Note the last 3 shouldn't affect you if on the same machine but I included them based on the title and to be comprehensive.
It's not especially hard. If you stick to conventions then with a little bit of configuration it boils down to this:
cap deploy
...however there is sometimes a bit of effort needed up front to get the workflow in place.
The good news is that lots of people have packaged up solutions and stacks for RoR that you can just plug and play. For example, google ec2onrails - this is a packaged Ubuntu image and set of capistrano tasks for running rails apps in Amazon's EC2 cloud, with lots of common stuff set up already out of the box.
Choose a good hosting provider and you should be able to find something similar for that also.
An easy way to deploy Rails apps is to use Phusion Passenger. Deployment doesn't get much easier than that for any programming language or framework. You can do that on a Mac server.
Another really easy way to deploy rails is with jruby and the glassfish gem.

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