VRFS-3728 ios client sync api tweaks

ruby/lib/jam_ruby/models/jam_track.rb

@@ -477,13 +477,14 @@ module JamRuby
         .where(user_id: user_id)
         .order('created_at DESC')
         .limit(1)
-      jtx_created.created_at.to_i
+      jtx_created.first.created_at.to_i
     end
 
     def self.mixdownChecksum(user_id, jam_track_id)
       dates = JamTrackMixdown
         .select('created_at')
         .where(user_id:  user_id, jam_track_id: jam_track_id)
+        .order(:id)
       
       dates = dates.map do |date|
         date.created_at.to_i.to_s

web/app/controllers/api_jam_tracks_controller.rb

@@ -106,20 +106,19 @@ class ApiJamTracksController < ApiController
       else
         # if the requested jamtrack is not purchased, send status code 204
         if 0 == JamTrack.where(id: jtid, user_id: current_user.id).count
-          head(204)
+          head(:no_content)
           return
         end
       end
     elsif params[:syncbuys]
       syncbuys = params[:syncbuys].to_i
-      if 0 == syncbuys
-        head(204) 
-        return 
-      end
       latestPurchase = JamTrack.latestPurchase(current_user.id)
-      if 0 < latestPurchase && (latestPurchase < syncbuys)
-        head 204, latestpurchase: latestPurchase
+      if 0 == syncbuys || (0 < latestPurchase && (latestPurchase <= syncbuys))
+        head :no_content, latestpurchase: latestPurchase
         return 
+      else
+        head :ok, latestpurchase: latestPurchase
+        return
       end
     end
     head(:ok)