This library provides integration of money gem with Rails.
Use 'monetize' to specify which fields you want to be backed by Money objects and helpers provided by the money gem.
Currently, this library is in active development mode, so if you would like to have a new feature feel free to open a new issue here. You are also welcome to contribute to the project.
Add this line to your application's Gemfile:
gem 'money-rails'
And then execute:
$ bundle
Or install it yourself as:
$ gem install money-rails
You may also install money configuration initializer:
$ rails g money_rails:initializer
There, you can define the default currency value and set other configuration parameters for the rails app.
If you want to add money field to product model you may use add_money
helper. That
helper might be customized inside MoneyRails.configure
block. You should customize
add_money
helper to match the most common use case and utilize it across all migrations.
class MonetizeProduct < ActiveRecord::Migration
def change
add_money :products, :price
# OR
change_table :products do |t|
t.money :price
end
end
end
add_money
helper is revertable, so you may use it inside change
migrations.
If you writing separate up
and down
methods, you may use remove_money
helper.
For example, we create a Product model which has an integer price_cents column and we want to handle it by using a Money object instead:
class Product < ActiveRecord::Base
monetize :price_cents
end
Now each Product object will also have an attribute called price
which
is a Money object and can be used for money comparisons, conversions etc.
In this case the name of the money attribute is created automagically by removing the
_cents
suffix of the column name.
If you are using another db column name or you prefer another name for the
money attribute, then you can provide as
argument with a string
value to the monetize
macro:
monetize :discount_subunit, :as => "discount"
Now the model objects will have a discount
attribute which
is a Money object, wrapping the value of discount_subunit
column to a
Money instance.
If you want to allow the assignment of nil and/or blank values to a specific
monetized field, you can use the :allow_nil
parameter like this:
# in Product model
monetize :optional_price_cents, :allow_nil => true
# then blank assignments are permitted
product.optional_price = nil
product.save # returns without errors
product.optional_price # => nil
product.optional_price_cents # => nil
You can also pass along numericality validation options such as this:
monetize :price_in_a_range_cents, :allow_nil => true,
:numericality => {
:greater_than_or_equal_to => 0,
:less_than_or_equal_to => 10000
}
Money
is available as a field type to supply during a field definition:
class Product
include Mongoid::Document
field :price, type: Money
end
obj = Product.new
# => #<Product _id: 4fe865699671383656000001, _type: nil, price: nil>
obj.price
# => nil
obj.price = Money.new(100, 'EUR')
# => #<Money cents:100 currency:EUR>
obj.price
#=> #<Money cents:100 currency:EUR>
obj.save
# => true
obj
# => #<Product _id: 4fe865699671383656000001, _type: nil, price: {:cents=>100, :currency_iso=>"EUR"}>
obj.price
#=> #<Money cents:100 currency:EUR>
## You can access the money hash too :
obj[:price]
# => {:cents=>100, :currency_iso=>"EUR"}
The usual options on field
as index
, default
, ..., are available.
Method return values can be converted in the same way attributes are converted. For example:
class Transaction < ActiveRecord::Base
monetize :price_cents
monetize :tax_cents
monetize :total_cents
def total_cents
return price_cents + tax_cents
end
end
Now each Transaction object has a method called total
which returns a Money object.
Money-rails supports a set of options to handle currencies for your monetized fields. The default option for every conversion is to use the global default currency of Money library, as given in the configuration initializer of money-rails:
# config/initializers/money.rb
MoneyRails.configure do |config|
# set the default currency
config.default_currency = :usd
end
In many cases this is not enough, so there are some other options to satisfy your needs.
You can define a specific currency for an activerecord model (not for mongoid).
This currency is used for the creation and conversions of the Money objects
referring to every monetized attributes of the specific model.
This means it overrides the global default currency of Money library.
To attach a currency to a model use the register_currency
macro:
# app/models/product.rb
class Product < ActiveRecord::Base
# Use EUR as model level currency
register_currency :eur
monetize :discount_subunit, :as => "discount"
monetize :bonus_cents
end
Now product.discount
and product.bonus
will return a Money
object using EUR as currency, instead of the default USD.
By using the key :with_currency
with a currency symbol value in
the monetize
macro call, you can define a currency in a more
granular way. This way you attach a currency only to the specific monetized
model attribute. It also allows to override both the model level
and the global default currency:
# app/models/product.rb
class Product < ActiveRecord::Base
# Use EUR as model level currency
register_currency :eur
monetize :discount_subunit, :as => "discount"
monetize :bonus_cents, :with_currency => :gbp
end
In this case the product.bonus
will return a Money object of GBP
currency, whereas product.discount.currency_as_string # => EUR
All the previous options do not require any extra model field to hold
currency values. If you need to provide differrent currency per model
instance, then you need to add a column with the name currency
in your db table. Money-rails will discover this automatically,
and will use this knowledge to override the model level and global
default values. Non-nil instance currency values also override attribute
currency values, so they have the highest precedence.
class Transaction < ActiveRecord::Base
# This model has a separate currency column
attr_accessible :amount_cents, :currency, :tax_cents
# Use model level currency
register_currency :gbp
monetize :amount_cents
monetize :tax_cents
end
# Now instantiating with a specific currency overrides
# the model and global currencies
t = Transaction.new(:amount_cents => 2500, :currency => "CAD")
t.amount == Money.new(2500, "CAD") # true
You can handle a bunch of configuration params through money.rb
initializer:
MoneyRails.configure do |config|
# To set the default currency
#
config.default_currency = :usd
# Add custom exchange rates
config.add_rate "USD", "CAD", 1.24515
config.add_rate "CAD", "USD", 0.803115
# To handle the inclusion of validations for monetized fields
# The default value is true
#
config.include_validations = true
# Register a custom currency
#
# config.register_currency = {
# :priority => 1,
# :iso_code => "EU4",
# :name => "Euro with subunit of 4 digits",
# :symbol => "€",
# :symbol_first => true,
# :subunit => "Subcent",
# :subunit_to_unit => 10000,
# :thousands_separator => ".",
# :decimal_mark => ","
# }
end
default_currency
: Set the default (application wide) currency (USD is the default)include_validations
: Permit the inclusion of avalidates_numericality_of
validation for each monetized field (the default is true)register_currency
: Register one custom currency. This option can be used more than once to set more custom currencies. The value should be a hash of all the necessary key/value pairs (important keys::priority
,:iso_code
,:name
,:symbol
,:symbol_first
,:subunit
,:subunit_to_unit
,:thousands_separator
,:decimal_mark
).add_rate
: Provide custom exchange rate for currencies in one direction only! This rate is added to the attached bank object.default_bank
: The default bank object holding exchange rates etc. (https://github.com/RubyMoney/money#currency-exchange)
- the
currency_symbol
helper method
<%= currency_symbol %>
This will render a span
dom element with the default currency symbol.
- the
humanized_money
helper method
<%= humanized_money @money_object %>
This will render a formatted money value without the currency symbol and
without the cents part if it contains only zeros (uses
:no_cents_fi_whole flag
).
- humanize with symbol helper
<%= humanized_money_with_symbol @money_object %>
This will render a formatted money value including the currency symbol and without the cents part if it contains only zeros.
- get the money value without the cents part
<%= money_without_cents @money_object %>
This will render a formatted money value without the currency symbol and without the cents part.
- get the money value without the cents part and including the currency symbol
<%= money_without_cents_and_with_symbol @money_object %>
This will render a formatted money value including the currency symbol and without the cents part.
If you use Rspec there is an test helper implementation.
Just write require "money-rails/test_helpers"
in spec_helper.rb and
include MoneyRails::TestHelpers
inside a describe block you want to
use the helper.
- the
monetize
matcher
monetize(:price_cents).should be_true
This will ensure that a column called price_cents
is being monetized.
monetize(:price_cents).as(:discount_value).should be_true
By using as
chain you can specify the exact name to which a monetized
column is being mapped.
monetize(:price_cents).with_currency(:gbp).should be_true
By using the with_currency
chain you can specify the expected currency
for the chosen money attribute. (You can also combine all the chains.)
For examples on using the test_helpers look at test_helpers_spec.rb
- ActiveRecord (>= 3.x)
- Mongoid (2.x, 3.x)
- MRI Ruby >= 1.9.2
You can see a full list of the currently supported interpreters in travis.yml
- Andreas Loupasakis (https://github.com/alup)
- Shane Emmons (https://github.com/semmons99)
- Simone Carletti (https://github.com/weppos)
MIT License. Copyright 2012 RubyMoney.