Deploy Rails with Oracle on Windows

An application I’m developing is due to go public around Christmas. I thought the best way to get to grips with deployment would be to set up a little test application, before trying to move all my code onto the server. This guide will consist of 3 parts:

Installing Rails
My-first-app with Oracle
Pen of pesky Mongrels

I’ll be using Windows Server, Oracle 10g, Mongrel & Pen. Many thanks to Brian Hogan for his informative talk at RailsConf which made the whole process very easy. See Deployment Strategies for Rails on Windows Servers for more detailed information.

Part 1: Installing Rails

Install Ruby

Download the one click windows installer. When installing, uncheck ‘SciTE’ – there are better editors available. Also, make sure ‘Enable RubyGems’ is checked. This is the package manager for Ruby, used to install Rails itself and myriad of other stuff.

Install to ‘c:\program files\ruby’ (or your installation path), then add ‘c:\program files\ruby\bin’ to your PATH for command line stuff.

Goto ‘Control Panel\System’, select the ‘Advanced’ tab and click ‘Environment Variables’. Look under user variables. If PATH isn’t already defined, click ‘New’.

* Variable name = âPATHâ
* Variable value = â%PATH%;c:\program files\ruby\binâ

Note the ‘;’ separator in the value string. If PATH is already defined just add ‘;c:\program files\ruby\bin’ to the end of it.

Install Rails

Now that we have ruby installed, we can use RubyGems to install rails.

gem install rails --include-dependencies

Yes, it is that easy.

My-first-app

Create your application skeleton and start the server:

rails path/to/your/new/application
cd path/to/your/new/application
ruby script/server

Congratulations! You’re now on Rails.

Part 2: Test Oracle with a simple app

Oracle can be tricky. It’s probably best to get it working with a simple app first, to minimise headaches later.

This guide assumes you are either:

connecting to an Oracle Database installed on your local machine.
connecting to a remote database using Oracle Instant Client installed on your local machine.

If you do not have at least the client software installed, the Ruby-Oracle driver will complain that it can’t find files such as oci.dll.

Install Oracle Database Driver

Download the ruby oracle driver and install with:

ruby ruby-oci8-1.0.0-rc3-mswin32.rb

You can test your connection to the database with the following one-liner:

ruby -r oci8 -e "OCI8.new('username', 'password', '127.0.0.1:1521/orcl').exec('SELECT * FROM test_table') do |r| puts r.join('|'); end"

Of course, make sure the schema & table that you are testing exists!

Create a User

Using SQLPlus, create a user with DBA privileges that you can use for this application.

GRANT dba TO ruby IDENTIFIED BY ruby;
ALTER USER ruby DEFAULT TABLESPACE users TEMPORARY TABLESPACE temp;
EXIT

Edit: Granting DBA access is not advised. Only the necessary privileges (CREATE TABLE, CREATE SEQUENCE) etc should be used.

Create a Table

CREATE TABLE comics (
	id NUMBER(10) NOT NULL,
	title VARCHAR2(60),
	issue NUMBER(4),
	publisher VARCHAR2(60),
	PRIMARY KEY (id)
);
CREATE SEQUENCE comics_seq;

Alternatively use this SQL file to create the application table, COMICS.

sqlplus ruby/ruby@rails @comics.sql

Note, in this case the database SID is rails. The default SID for Oracle Enterprise Edition 10g is orcl, for Express Edition it’s XE.

Create a dinky Application

Your application skeleton:

rails comics_catalog
cd comics_catalog

Edit comics_catalog/config/databases.yml – rails needs to know your login & password info.

Within your project directory, there is a directory called config and in it is a file named database.yml. You need to edit database.yml using your favourite text editor. Initially, the file will look like this:

development:
	adapter: mysql
	database: rails_development
	host: localhost
	username: root
	password:

# Warning: The database defined as 'test' will be erased and
# re-generated from your development database when you run 'rake'.
# Do not set this db to the same as development or production.
test:
	adapter: mysql
	database: rails_test
	host: localhost
	username: root
	password:

production:
	adapter: mysql
	database: rails_production
	host: localhost
	username: root
	password:

Change the development properties as follows:

development: adapter: oci username: ruby password: ruby host: 127.0.0.1:1234/orcl

host: takes a connect string of the form <ip_address>:<port>/<database> for the machine that your Oracle instance resides on.

Use the magical scaffold command to build a web based CRUD interface to the table we created above…

ruby script/generate scaffold Comic

Now you can access your Rails Comic Catalog application on your own development machine, using your favourite Web browser. Just access the following URL: http://localhost:3000/comics/list

Part 3: Pen of pesky Mongrels…

Before you go any further, make sure your app works in production mode!

Install Mongrel

The easiest way to get started with Mongrel is to install it via RubyGems:

gem install mongrel

Select the highest stable version number marked (mswin32).

Run Mongrel in the background with:

cd myrailsapp
mongrel_rails start -d

and stop it with:

mongrel_rails stop

There’s quite a few options you can set for the start command. Use mongrel_rails start -h to see them all.

Mongrel as a Service

Install the gem (pick the most recent one):

gem install win32-service
gem install mongrel_service

Install your app as a service:

mongrel_rails service::install âN comics_4001 -c c:\my\path\to\myapp âp 4001 âe production

Your app will then appear under ‘services’ in Computer Management (accessed via Control Panel or by right clicking on My Computer)

You can then set the service to start automagically. Right click on ‘comics_4001’, choose ‘properties’ and change the startup type to ‘automatic’.

This is really all you need for a small application – perhaps an internal company app or something.

Cons:

You don’t get page caching
Doesn’t scale
Rails is single threaded so user requests get queued up.

While rails is serving an action to one user, all the other users need to wait. This is bad if some of your actions take a while, which is why we need Pen…

Load Balancing Mongrels with Pen

Pen requires cygwin1.dll, so make sure it’s in the same directory as pen.exe. Also, make you get the one with the ‘a’ suffix – the other version doesn’t work for some reason.

To run pen as a service you need the Windows Server Resource Kit Tools. Install it somewhere. To keep things simple I’ll use c:\reskit

Start a couple of mongrels:

mongrel_rails service::install âN comics_4001 -c c:\my\path\to\myapp âp 4001 âe production
mongrel_rails service::install âN comics_4002 -c c:\my\path\to\myapp âp 4002 âe production

You could write a batch file to start and stop these multiple servers.

The following command will balance your mongrels just fine:

pen 4000 localhost:4001 localhost:4002

But to do things properly, keep reading.

Pen as a Service

Install pen as a service using srvany.exe from the reskit:

c:\reskit\instsrv Pen c:\reskit\srvany.exe
>> The service was successfuly added!

Set some parameters with regedit. Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Pen and add a new key called Parameters. Add the following three String values to the parameters key:

Application = pen.exe
AppParameters = -f 4000 localhost:4001 localhost:4002
AppDirectory = c:\pen

Start the pen service from ‘Services’ or with the command:

net start pen

Remove with:

sc delete pen

Pen will then chug along happily and is suitable for most apps with a few users. You still don’t get page caching, for that you need Apache, but this solution is free, simple and performs moderately well.

References:
tutorial provided by Oracle
Deployment Strategies for Rails on Windows Servers

ginger leprechaun

Barry Keenan's notes on Ruby, PHP, JavaScript and Web Development.