#434

backend/app/controllers/counts_exports_controller.rb

@@ -1,6 +1,29 @@
 class CountsExportsController < ApplicationController
   wrap_parameters false
 
+  def prepare
+    locale = resolve_locale!
+    payload = request.request_parameters.merge(request.query_parameters)
+    exporter = CountsExporter.new(payload, language_code: locale.language_code)
+    session[:counts_export_owner] ||= SecureRandom.hex(32)
+    token = CountsExportDownload.prepare(exporter, session[:counts_export_owner])
+    response.headers['Cache-Control'] = 'private, no-store'
+    render json: { token: }
+  rescue ArgumentError, TypeError, KeyError, JSON::ParserError
+    head :bad_request
+  end
+
+  def download
+    file = CountsExportDownload.find(params[:token], session[:counts_export_owner])
+    return head :not_found unless file
+
+    response.headers['Cache-Control'] = 'private, no-store'
+    send_file file.fetch('path'),
+              filename: "counts-#{ file.fetch('resource') }.#{ file.fetch('format') }",
+              type: file['format'] == 'json' ? 'application/json' : 'text/csv',
+              disposition: 'attachment'
+  end
+
   def index
     locale = resolve_locale!
     payload = request.request_parameters.except('authenticity_token')

backend/app/controllers/counts_tables_controller.rb

@@ -1,7 +1,20 @@
 class CountsTablesController < ApplicationController
+  def definition
+    resolve_locale!
+    definition = CountsResourceDefinition.new(params[:resource])
+    render json: { fields: definition.metadata,
+                   axes: { latest: definition.axes(false), history: definition.axes(true) },
+                   grains: CountsAxes::GRAINS }
+  rescue ArgumentError
+    head :bad_request
+  end
+
   def index
     resolve_locale!
     render json: CountsTableQuery.new(request.query_parameters).call
+  rescue CountsTableQuery::TooManyColumns
+    render json: { error: 'too_many_columns', max_columns: CountsTableQuery::MAX_COLUMNS },
+           status: :unprocessable_entity
   rescue ArgumentError, TypeError, KeyError, JSON::ParserError
     head :bad_request
   end