app/helpers/application_helper.rb

   1 module ApplicationHelper
   2
   3   ALL_PERMISSIONS = {read: true, write: true, manage: true}
   4
   5   def current_user
   6     controller.current_user
   7   end
   8
   9   def invalidate_permissions_cache
  10     Rails.cache.delete_matched(/^groups_for_user_/)
  11   end
  12
  13   def current_groups
  14     return {} unless current_user
  15     Rails.cache.fetch "groups_for_user_#{current_user.uuid}" do
  16       permissions_from = {}
  17       todo = {current_user.uuid => true}
  18       done = {}
  19       while !todo.empty?
  20         lookup_uuids = todo.keys
  21         lookup_uuids.each do |uuid| done[uuid] = true end
  22         todo = {}
  23         Link.where('tail_uuid in (?) and link_class = ? and head_kind = ?',
  24                    lookup_uuids,
  25                    'permission',
  26                    'orvos#group').each do |link|
  27           unless done.has_key? link.head_uuid
  28             todo[link.head_uuid] = true
  29           end
  30           link_permissions = {}
  31           case link.name
  32           when 'can_read'
  33             link_permissions = {read:true}
  34           when 'can_write'
  35             link_permissions = {read:true,write:true}
  36           when 'can_manage'
  37             link_permissions = ALL_PERMISSIONS
  38           end
  39           permissions_from[link.tail_uuid] ||= {}
  40           permissions_from[link.tail_uuid][link.head_uuid] ||= {}
  41           link_permissions.each do |k,v|
  42             permissions_from[link.tail_uuid][link.head_uuid][k] ||= v
  43           end
  44         end
  45       end
  46       search_permissions(current_user.uuid, permissions_from)
  47     end
  48   end
  49
  50   protected
  51
  52   def search_permissions(start, graph, merged={}, upstream_mask=nil, upstream_path={})
  53     nextpaths = graph[start]
  54     return merged if !nextpaths
  55     return merged if upstream_path.has_key? start
  56     upstream_path[start] = true
  57     upstream_mask ||= ALL_PERMISSIONS
  58     nextpaths.each do |head, mask|
  59       merged[head] ||= {}
  60       mask.each do |k,v|
  61         merged[head][k] ||= v if upstream_mask[k]
  62       end
  63       search_permissions(head, graph, merged, upstream_mask.select { |k,v| v && merged[head][k] }, upstream_path)
  64     end
  65     upstream_path.delete start
  66     merged
  67   end
  68
  69 end