Added locking around update and delete methods on main API objects. This should remov...

[rails.git] / app / models / node.rb

diff --git a/app/models/node.rb b/app/models/node.rb
index 679048b4e3aa18dc453cde9776410b3b7ba0cb2b..01b0f220e6ed565a1db167ea265d39f85b670ab2 100644 (file)
--- a/app/models/node.rb
+++ b/app/models/node.rb
@@ -70,7 +70,7 @@ class Node < ActiveRecord::Base
       doc.find('//osm/node').each do |pt|
         return Node.from_xml_node(pt, create)
       end
-    rescue LibXML::XML::Error => ex
+    rescue LibXML::XML::Error, ArgumentError => ex
       raise OSM::APIBadXMLError.new("node", xml, ex.message)
     end
   end
@@ -123,55 +123,60 @@ class Node < ActiveRecord::Base
   # Should probably be renamed delete_from to come in line with update
   def delete_with_history!(new_node, user)
     unless self.visible
-      raise OSM::APIAlreadyDeletedError.new
+      raise OSM::APIAlreadyDeletedError.new("node", new_node.id)
     end
 
     # need to start the transaction here, so that the database can 
     # provide repeatable reads for the used-by checks. this means it
     # shouldn't be possible to get race conditions.
     Node.transaction do
+      self.lock!
       check_consistency(self, new_node, user)
-      if WayNode.find(:first, :joins => "INNER JOIN current_ways ON current_ways.id = current_way_nodes.id", :conditions => [ "current_ways.visible = ? AND current_way_nodes.node_id = ?", true, self.id ])
-        raise OSM::APIPreconditionFailedError.new
-      elsif RelationMember.find(:first, :joins => "INNER JOIN current_relations ON current_relations.id=current_relation_members.id", :conditions => [ "visible = ? AND member_type='node' and member_id=? ", true, self.id])
-        raise OSM::APIPreconditionFailedError.new
-      else
-        self.changeset_id = new_node.changeset_id
-        self.visible = false
-        
-        # update the changeset with the deleted position
-        changeset.update_bbox!(bbox)
-        
-        save_with_history!
-      end
+      way = WayNode.find(:first, :joins => :way, 
+                         :conditions => [ "current_ways.visible = ? AND current_way_nodes.node_id = ?", true, self.id ])
+      raise OSM::APIPreconditionFailedError.new("Node #{self.id} is still used by way #{way.way.id}.") unless way.nil?
+      
+      rel = RelationMember.find(:first, :joins => :relation, 
+                                :conditions => [ "visible = ? AND member_type='Node' and member_id=? ", true, self.id])
+      raise OSM::APIPreconditionFailedError.new("Node #{self.id} is still used by relation #{rel.relation.id}.") unless rel.nil?
+
+      self.changeset_id = new_node.changeset_id
+      self.visible = false
+      
+      # update the changeset with the deleted position
+      changeset.update_bbox!(bbox)
+      
+      save_with_history!
     end
   end
 
   def update_from(new_node, user)
-    check_consistency(self, new_node, user)
-
-    # update changeset first
-    self.changeset_id = new_node.changeset_id
-    self.changeset = new_node.changeset
-
-    # update changeset bbox with *old* position first
-    changeset.update_bbox!(bbox);
-
-    # FIXME logic needs to be double checked
-    self.latitude = new_node.latitude 
-    self.longitude = new_node.longitude
-    self.tags = new_node.tags
-    self.visible = true
-
-    # update changeset bbox with *new* position
-    changeset.update_bbox!(bbox);
-
-    save_with_history!
+    Node.transaction do
+      self.lock!
+      check_consistency(self, new_node, user)
+      
+      # update changeset first
+      self.changeset_id = new_node.changeset_id
+      self.changeset = new_node.changeset
+      
+      # update changeset bbox with *old* position first
+      changeset.update_bbox!(bbox);
+      
+      # FIXME logic needs to be double checked
+      self.latitude = new_node.latitude 
+      self.longitude = new_node.longitude
+      self.tags = new_node.tags
+      self.visible = true
+      
+      # update changeset bbox with *new* position
+      changeset.update_bbox!(bbox);
+      
+      save_with_history!
+    end
   end
   
   def create_with_history(user)
     check_create_consistency(self, user)
-    self.id = nil
     self.version = 0
     self.visible = true
 
@@ -187,27 +192,33 @@ class Node < ActiveRecord::Base
     return doc
   end
 
-  def to_xml_node(user_display_name_cache = nil)
+  def to_xml_node(changeset_cache = {}, user_display_name_cache = {})
     el1 = XML::Node.new 'node'
     el1['id'] = self.id.to_s
     el1['lat'] = self.lat.to_s
     el1['lon'] = self.lon.to_s
     el1['version'] = self.version.to_s
     el1['changeset'] = self.changeset_id.to_s
-    
-    user_display_name_cache = {} if user_display_name_cache.nil?
 
-    if user_display_name_cache and user_display_name_cache.key?(self.changeset.user_id)
+    if changeset_cache.key?(self.changeset_id)
+      # use the cache if available
+    else
+      changeset_cache[self.changeset_id] = self.changeset.user_id
+    end
+
+    user_id = changeset_cache[self.changeset_id]
+
+    if user_display_name_cache.key?(user_id)
       # use the cache if available
     elsif self.changeset.user.data_public?
-      user_display_name_cache[self.changeset.user_id] = self.changeset.user.display_name
+      user_display_name_cache[user_id] = self.changeset.user.display_name
     else
-      user_display_name_cache[self.changeset.user_id] = nil
+      user_display_name_cache[user_id] = nil
     end
 
-    if not user_display_name_cache[self.changeset.user_id].nil?
-      el1['user'] = user_display_name_cache[self.changeset.user_id]
-      el1['uid'] = self.changeset.user_id.to_s
+    if not user_display_name_cache[user_id].nil?
+      el1['user'] = user_display_name_cache[user_id]
+      el1['uid'] = user_id.to_s
     end
 
     self.tags.each do |k,v|
@@ -260,7 +271,7 @@ class Node < ActiveRecord::Base
   ##
   # dummy method to make the interfaces of node, way and relation
   # more consistent.
-  def fix_placeholders!(id_map)
+  def fix_placeholders!(id_map, placeholder_id = nil)
     # nodes don't refer to anything, so there is nothing to do here
   end