Using with ActiveRecord

Example with ActiveRecord

    class Datastream < ActiveRecord::Base
      belongs_to :feed
    end

    class Feed < ActiveRecord::Base
      has_many :datastreams
      extend Cosm::Base
      is_cosm :feed
    end

Provided methods

    @cosm_feed = feed.to_cosm # returns an instance of Cosm::Feed
    @cosm_feed.to_json(:version => "1.0.0") # converts your feed and associated datastreams into Cosm V2 JSON
    @cosm_feed.as_json(:version => "0.6-alpha") # provides a json hash for 0.6-alpha
    @cosm_feed.to_xml(:version => "0.5.1") # converts your feed and associated datastreams into Cosm V2 XML (EEML)

Supported formats

• JSON "1.0.0" - used by Cosm API v2
• JSON "0.6-alpha" - used by Cosm API v1
• XML "0.5.1" - used by Cosm API v2
• XML "5" - used by Cosm API v1
• CSV v1 - used by Cosm API v1
• CSV v2 - used by Cosm API v2

Mapped fields

See [the Cosm Api docs] 1 for a description of each field.

By default the gem expects your object to have the following fields:

Feeds

• creator
• datastreams
• description
• email
• feed
• icon
• id
• location_disposition
• location_domain
• location_ele
• location_exposure
• location_lat
• location_lon
• location_name
• private
• status
• tags
• title
• updated
• website

Datastreams

• current_value
• datapoints
• feed_creator
• feed_id
• id
• max_value
• min_value
• tags
• unit_label
• unit_symbol
• unit_type
• updated

Datapoints

• at
• value
• feed_id
• datastream_id

If you use different field names, want to map custom fields or want to map fields onto instance methods you can:

    class Feed < ActiveRecord::Base
      extend Cosm::Base

      has_one :geo_location
      is_cosm :feed, {:location_lat => :geo_lat, :location_lon => :geo_lon}


      def geo_lat
        geo_location.try(:latitude)
      end

      def geo_lon
        geo_location.try(:longitude)
      end
    end