json query examples

json_query_examples.rb

# We pulled out the scheduled delivery date to render in our order status page
shipment.tracking_info['scheduled_delivery_date']

# We created some scopes to keep track of shipments in different stages of delivery
scope :delivered, -> { where("tracking_info->>'status' = 'delivered'") }

# Syntax could get a little ugly with slightly more complicated queries
Shipment.where("promised_arrival_date < (tracking_info->>'actual_delivery_date')::date")

# We got it working with ransack, a gem we use for creating search forms
# in controller
@found = Shipment.search(params[:q])

# in view
= search_form_for @found do |f|
  = f.select :tracking_info_status_eq, Shipment.unique_tracking_statuses

# In the model you have to make your own ransacker
ransacker :tracking_info_status do |parent|
  Arel::Nodes::InfixOperation.new('->>',
                                  parent.table[:tracking_info],
                                  Arel::Nodes.build_quoted('status'))
end