This is a rails plugin/engine to embue your application with OData features (so its data can be readily consumed by an OData client).

In OData, a service exposes a number of workspace. Each workspace is backed by a schema and contains a collection of entity collections. An entity collection is a related set of records.

Configure the plugin by adding a number of schema objects to OData::Edm::DataServices.schemas. Each schema is an instance of a subclass of OData::AbstractSchema::Base. We currently only support two implementations, and the specific implementation determines how to load the records, mapping the records' properties to/from Edm data types, and handling filtering, sorting, and data retrieval.

• OData::ActiveRecordSchema::Base -- either you give it a list or it iterate over all your models exposing each as OData entities

and

• OData::InMemorySchema::Base -- this takes in a list of objects which are exposed as OData entities

The accessible OData service will be a read-only provider.

This code is not heavily tested. It is alpha quality at best. Expect the API to change drastically over time.

OData V4:

• http://www.odata.org
• http://www.odata.org/documentation

Rails 4 or higher.

Put this line in your Gemfile:

gem 'odata_server'

Run the bundle command to install it.

Then add the following lines to an initializer (ex: odata_server.rb):

# ActiveRecordSchema

ar_schema = OData::ActiveRecordSchema::Base.new('AR', classes: Foo)
OData::Edm::DataServices.schemas << ar_schema

# OR

OData::Edm::DataServices.schemas << OData::ActiveRecordSchema::Base.new

By giving a list of classes to ActiveRecordSchema, it will represent only theses classes. Without classes option, all the models will be represented. ActiveRecordSchema can take a reflection option too (default is false): if true the models associations will be shown.

# InMemorySchema

class Foo
  attr_reader :foo, :bar, :baz

  def initialize(foo, bar, baz)
    @foo = foo
    @bar = bar
    @baz = baz
  end
end

inmem = OData::InMemorySchema::Base.new("InMem", classes: Foo)
OData::Edm::DataServices.schemas << inmem
(1..20).each do |n|
  inmem.find_entity_type("Foo").entities.append(Foo.new(n, "test", "test #{n}"))
end

ActiveRecordSchema and InMemorySchema can either take a single classe or an array of classes.

Then, mount the OData::Engine in routes.rb:

mount OData::Engine, at: '/service/OData'

Restart your sever and you can visit the /service/Odata url that is the service base.

See https://github.com/lmcalpin/odata_provider_example_rb for an example application that uses this gem.

• Update the core for OData v4
• Add support for $search option
• Update and add more tests