- begin
- relation = Relation.find(params[:id])
-
- if relation.visible
-
- # first collect nodes, ways, and relations referenced by this relation.
-
- ways = Way.find_by_sql("select w.* from current_ways w,current_relation_members rm where "+
- "rm.member_type='way' and rm.member_id=w.id and rm.id=#{relation.id}");
- nodes = Node.find_by_sql("select n.* from current_nodes n,current_relation_members rm where "+
- "rm.member_type='node' and rm.member_id=n.id and rm.id=#{relation.id}");
- # note query is built to exclude self just in case.
- relations = Relation.find_by_sql("select r.* from current_relations r,current_relation_members rm where "+
- "rm.member_type='relation' and rm.member_id=r.id and rm.id=#{relation.id} and r.id<>rm.id");
-
- # now additionally collect nodes referenced by ways. Note how we recursively
- # evaluate ways but NOT relations.
-
- node_ids = nodes.collect {|node| node.id }
- way_node_ids = ways.collect { |way|
- way.way_nodes.collect { |way_node| way_node.node_id }
- }
- way_node_ids.flatten!
- way_node_ids.uniq
- way_node_ids -= node_ids
- nodes += Node.find(way_node_ids)
-
- # create XML.
- doc = OSM::API.new.get_xml_doc
- visible_nodes = {}
- user_display_name_cache = {}
-
- nodes.each do |node|
- if node.visible? # should be unnecessary if data is consistent.
- doc.root << node.to_xml_node(user_display_name_cache)
- visible_nodes[node.id] = node
- end
- end
- ways.each do |way|
- if way.visible? # should be unnecessary if data is consistent.
- doc.root << way.to_xml_node(visible_nodes, user_display_name_cache)
- end
- end
- relations.each do |rel|
- if rel.visible? # should be unnecessary if data is consistent.
- doc.root << rel.to_xml_node(user_display_name_cache)
- end
- end
- # finally add self and output
- doc.root << relation.to_xml_node(user_display_name_cache)
- render :text => doc.to_s, :content_type => "text/xml"
-
- else
-
- render :text => "", :status => :gone
- end