#434

backend/app/services/counts_axes.rb

@@ -1,4 +1,10 @@
 class CountsAxes
+  MAX_AXES = 8
+  MASKED_VALUE = '__counts_private__'.freeze
+  PUBLIC_FIELDS = ['created_at', 'event_type'].freeze
+  class TooManyAxes < ArgumentError; end
+  class PrivateCondition < ArgumentError; end
+
   GRAINS = ['year', 'quarter', 'month', 'week', 'day', 'hour'].freeze
 
   def self.time_expression(expression, grain, timezone)
@@ -36,13 +42,14 @@ class CountsAxes
     @rows = parse(population.params.fetch('rows', ''))
     @columns = parse(population.params.fetch('cols', ''))
     @all = rows + columns
-    raise ArgumentError if all.length > 8 || all.map { _1['field'] }.uniq.length != all.length
+    raise TooManyAxes if all.length > MAX_AXES
+    raise ArgumentError if all.map { _1['field'] }.uniq.length != all.length
   end
 
   def expressions
     @expressions ||= all.map do |axis|
       field = axis.fetch('field')
-      case field
+      expression = case field
       when 'tags'
         "CASE WHEN tag_entry.tag_id IS NOT NULL " +
             "THEN CONCAT('internal:', tag_entry.tag_id) " +
@@ -53,6 +60,11 @@ class CountsAxes
         @definition.fields[field] == :datetime ? self.class.time_expression(
             expression, axis.fetch('grain', 'month'), @population.timezone) : expression
       end
+      if !HistoryAccess.admin? && !PUBLIC_FIELDS.include?(field)
+        expression = "CASE WHEN #{ HistoryAccess.sql(@definition.model, 'v') } " +
+            "THEN CAST((#{ expression }) AS CHAR) ELSE '#{ MASKED_VALUE }' END"
+      end
+      expression
     end
   end
 
@@ -73,6 +85,9 @@ class CountsAxes
       condition = @definition.changes.map do |field|
         "(changed.field_key = '#{ field }' AND #{ @population.changed_sql(field) })"
       end.join(' OR ')
+      unless HistoryAccess.admin?
+        condition = "(#{ condition }) OR NOT (#{ HistoryAccess.sql(@definition.model, 'v') })"
+      end
       result += " JOIN (#{ fields }) changed ON (#{ condition })"
     end
     result