CouchRest Model

CouchRest Model helps you define models that are stored as documents in your CouchDB database.

It supports useful features such as setting properties with typecasting, callbacks, validations, associations, and helps with creating CouchDB views to access your data.

CouchRest Model uses ActiveModel for a lot of the magic, so if you're using Rails, you'll need at least version 3.0. Releases since 2.0.0 are Rails 4.0 compatible, and we recommend Ruby 2.0+.

Documentation

Please visit the documentation project at http://www.couchrest.info. Your contributions would be greatly appreciated!

General API: http://rdoc.info/projects/couchrest/couchrest_model

See the update history for an up to date list of all the changes we've been working on recently.

Upgrading from an earlier version?

Pre 2.2: As of August 2016, dirty tracking has been radically re-factored away from ActiveModel::Dirty, which only has support for basic attributes, into a solution that uses Hashdiff, more details available in the pull request. The result is that some of ActiveModel's Dirty methods are no longer available, these are: changes_applied, restore_attributes, previous_changes, and changed_attributes.

Pre 2.0: As of June 2012, couchrest model no longer supports the view_by and view calls from the model. Views are no only accessed via a design document. If you have older code and wish to upgrade, please ensure you move to the new syntax for using views.

Pre 1.1: As of April 2011 and the release of version 1.1.0, the default model type key is 'type' instead of 'couchrest-type'. Simply updating your project will not work unless you migrate your data or set the configuration option in your initializers:

CouchRest::Model::Base.configure do |config|
  config.model_type_key = 'couchrest-type'
end

Install

Gem

$ sudo gem install couchrest_model

Bundler

If you're using bundler, define a line similar to the following in your project's Gemfile:

gem 'couchrest_model'

Configuration

CouchRest Model is configured to work out the box with no configuration as long as your CouchDB instance is running on the default port (5984) on localhost. The default name of the database is either the name of your application as provided by the Rails.application.class.to_s call (with /application removed) or just 'couchrest' if none is available.

The library will try to detect a configuration file at config/couchdb.yml from the Rails root or Dir.pwd. Here you can configuration your database connection in a Rails-like way:

development:
  protocol: 'https'
  host: sample.cloudant.com
  port: 443
  prefix: project
  suffix: test
  username: test
  password: user

Note that the name of the database is either just the prefix and suffix combined or the prefix plus any text you specify using use_database method in your models with the suffix on the end.

The example config above for example would use a database called "project_test". Here's an example using the use_database call:

class Project < CouchRest::Model::Base
  use_database 'sample'
end

# The database object would be provided as:
Project.database     #=> "https://test:user@sample.cloudant.com:443/project_sample_test"

Using instead of ActiveRecord in Rails

A common use case for a new project is to replace ActiveRecord with CouchRest Model, although they should work perfectly well together. If you no longer want to depend on ActiveRecord or any of its sub-dependencies such as sqlite, update your config/application.rb so the top looks something like:

# We don't need active record, so load everything but:
# require 'rails/all'
require 'action_controller/railtie'
require 'action_mailer/railtie'
require 'rails/test_unit/railtie'

You'll then need to make sure any references to config.active_record are removed from your environment files.

or alternatively below command do the same work

rails new <application-name> --skip-active-record

Now in the gem file just add [couchrest_model] and you are good to go.

Generators

Configuration

$ rails generate couchrest_model:config

Model

$ rails generate model person --orm=couchrest_model

General Usage

require 'couchrest_model'

class Cat < CouchRest::Model::Base

  property :name,      String
  property :lives,     Integer, :default => 9

  property :nicknames, [String]

  timestamps!

  design do
    view :by_name
  end

end

@cat = Cat.new(:name => 'Felix', :nicknames => ['so cute', 'sweet kitty'])

@cat.new?   # true
@cat.save

@cat['name']   # "Felix"

@cat.nicknames << 'getoffdamntable'

@cat = Cat.new
@cat.update_attributes(:name => 'Felix', :random_text => 'feline')
@cat.new? # false
@cat.random_text  # Raises error!

# Fetching by views, loading all results into memory
cats = Cat.by_name.all
cats.first.name # "Felix"

# Streaming views, for efficient memory usage
Cat.by_name.all do |cat|
  puts cat.name
end

Development

Preparations

CouchRest Model now comes with a Gemfile to help with development. If you want to make changes to the code, download a copy then run:

bundle install

That should set everything up for rake spec to be run correctly. Update the couchrest_model.gemspec if your alterations use different gems.

Testing

The most complete documentation is the spec/ directory. To validate your CouchRest install, from the project root directory run bundle install to ensure all the development dependencies are available and then rspec spec or bundle exec rspec spec.

We will not accept pull requests to the project without sufficient tests.

Contact

Please post bugs, suggestions and patches to the bug tracker at http://github.com/couchrest/couchrest_model/issues.

Follow us on Twitter: http://twitter.com/couchrest

Also, check https://twitter.com/search?q=couchrest