Add code to export csv for voting visualisation

.gitignore

@@ -29,3 +29,7 @@ coverage
 
 # Ignore the images generated by the rake task application:generate:cards
 public/cards
+
+# Ignore output of "export" rake tasks
+distances.csv
+people.csv

lib/tasks/application.rake

@@ -213,4 +213,25 @@ namespace :application do
       CardScreenshotter::PoliciesCategory.run
     end
   end
+
+  namespace :export do
+    # Data required for visualisation at https://github.com/openaustralia/visualise-votes-mds/blob/main/notebook.ipynb
+    desc "Export csv files required for voting visualisation"
+    task voting_visualisation: :environment do
+      # Export distances.csv
+      p = Member.current.where(house: "representatives").pluck(:person_id)
+      d = PeopleDistance.where(person1: p, person2: p).pluck(:person1_id, :person2_id, :distance_b)
+      File.open("distances.csv", "w") do |f|
+        f.write(%w[person1_id person2_id distance_b].to_csv)
+        d.each { |l| f.write(l.to_csv) }
+      end
+
+      # Export people.csv
+      info = Member.current.where(house: "representatives").map { |m| [m.person.id, m.person.name, m.person.latest_member.party] }
+      File.open("people.csv", "w") do |f|
+        f.write(%w[id name party].to_csv)
+        info.each { |l| f.write(l.to_csv) }
+      end
+    end
+  end
 end