X-Git-Url: https://git.openstreetmap.org/rails.git/blobdiff_plain/6c66507427961a22a8f282b5b2f4ab7fda1dad6f..010dc8719596add0fec05a7d43f677dffdf03beb:/app/models/way.rb

diff --git a/app/models/way.rb b/app/models/way.rb
index 97f44c117..4f988dc9d 100644
--- a/app/models/way.rb
+++ b/app/models/way.rb
@@ -89,7 +89,7 @@ class Way < ActiveRecord::Base
     return doc
   end
 
-  def to_xml_node(visible_nodes = nil, user_display_name_cache = nil)
+  def to_xml_node(visible_nodes = nil, changeset_cache = {}, user_display_name_cache = {})
     el1 = XML::Node.new 'way'
     el1['id'] = self.id.to_s
     el1['visible'] = self.visible.to_s
@@ -97,19 +97,25 @@ class Way < ActiveRecord::Base
     el1['version'] = self.version.to_s
     el1['changeset'] = self.changeset_id.to_s
 
-    user_display_name_cache = {} if user_display_name_cache.nil?
+    if changeset_cache.key?(self.changeset_id)
+      # use the cache if available
+    else
+      changeset_cache[self.changeset_id] = self.changeset.user_id
+    end
 
-    if user_display_name_cache and user_display_name_cache.key?(self.changeset.user_id)
+    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
 
     # make sure nodes are output in sequence_id order
@@ -198,80 +204,79 @@ class Way < ActiveRecord::Base
   end
 
   def update_from(new_way, user)
-    check_consistency(self, new_way, user)
-    unless new_way.preconditions_ok?
-      raise OSM::APIPreconditionFailedError("Cannot update way #{self.id}: data is invalid.")
+    Way.transaction do
+      self.lock!
+      check_consistency(self, new_way, user)
+      unless new_way.preconditions_ok?(self.nds)
+        raise OSM::APIPreconditionFailedError.new("Cannot update way #{self.id}: data is invalid.")
+      end
+      
+      self.changeset_id = new_way.changeset_id
+      self.changeset = new_way.changeset
+      self.tags = new_way.tags
+      self.nds = new_way.nds
+      self.visible = true
+      save_with_history!
     end
-
-    self.changeset_id = new_way.changeset_id
-    self.changeset = new_way.changeset
-    self.tags = new_way.tags
-    self.nds = new_way.nds
-    self.visible = true
-    save_with_history!
   end
 
   def create_with_history(user)
     check_create_consistency(self, user)
     unless self.preconditions_ok?
-      raise OSM::APIPreconditionFailedError("Cannot create way: data is invalid.")
+      raise OSM::APIPreconditionFailedError.new("Cannot create way: data is invalid.")
     end
     self.version = 0
     self.visible = true
     save_with_history!
   end
 
-  def preconditions_ok?
+  def preconditions_ok?(old_nodes = [])
     return false if self.nds.empty?
     if self.nds.length > APP_CONFIG['max_number_of_way_nodes']
       raise OSM::APITooManyWayNodesError.new(self.nds.length, APP_CONFIG['max_number_of_way_nodes'])
     end
-    self.nds.each do |n|
-      node = Node.find(:first, :conditions => ["id = ?", n])
-      unless node and node.visible
-        raise OSM::APIPreconditionFailedError.new("The node with id #{n} either does not exist, or is not visible")
+
+    # check only the new nodes, for efficiency - old nodes having been checked last time and can't
+    # be deleted when they're in-use.
+    new_nds = (self.nds - old_nodes).sort.uniq
+
+    unless new_nds.empty?
+      db_nds = Node.find(:all, :conditions => { :id => new_nds, :visible => true })
+
+      if db_nds.length < new_nds.length
+        missing = new_nds - db_nds.collect { |n| n.id }
+        raise OSM::APIPreconditionFailedError.new("Way #{self.id} requires the nodes with id in (#{missing.join(',')}), which either do not exist, or are not visible.")
       end
     end
+
     return true
   end
 
   def delete_with_history!(new_way, user)
     unless self.visible
-      raise OSM::APIAlreadyDeletedError
+      raise OSM::APIAlreadyDeletedError.new("way", new_way.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.
     Way.transaction do
+      self.lock!
       check_consistency(self, new_way, user)
-      if RelationMember.find(:first, :joins => "INNER JOIN current_relations ON current_relations.id=current_relation_members.id",
+      rel = RelationMember.find(:first, :joins => :relation,
                              :conditions => [ "visible = ? AND member_type='Way' and member_id=? ", true, self.id])
-        raise OSM::APIPreconditionFailedError.new("You need to make sure that this way is not a member of a relation.")
-      else
-        self.changeset_id = new_way.changeset_id
-        self.changeset = new_way.changeset
-
-        self.tags = []
-        self.nds = []
-        self.visible = false
-        save_with_history!
-      end
+      raise OSM::APIPreconditionFailedError.new("Way #{self.id} still used by relation #{rel.relation.id}.") if rel
+      
+      self.changeset_id = new_way.changeset_id
+      self.changeset = new_way.changeset
+
+      self.tags = []
+      self.nds = []
+      self.visible = false
+      save_with_history!
     end
   end
 
-  # Find nodes that belong to this way only
-  def unshared_node_ids
-    node_ids = self.nodes.collect { |node| node.id }
-
-    unless node_ids.empty?
-      way_nodes = WayNode.find(:all, :conditions => "node_id in (#{node_ids.join(',')}) and id != #{self.id}")
-      node_ids = node_ids - way_nodes.collect { |way_node| way_node.node_id }
-    end
-
-    return node_ids
-  end
-
   # Temporary method to match interface to nodes
   def tags_as_hash
     return self.tags
@@ -281,11 +286,11 @@ class Way < ActiveRecord::Base
   # if any referenced nodes are placeholder IDs (i.e: are negative) then
   # this calling this method will fix them using the map from placeholders 
   # to IDs +id_map+. 
-  def fix_placeholders!(id_map)
+  def fix_placeholders!(id_map, placeholder_id = nil)
     self.nds.map! do |node_id|
       if node_id < 0
         new_id = id_map[:node][node_id]
-        raise "invalid placeholder for #{node_id.inspect}: #{new_id.inspect}" if new_id.nil?
+        raise OSM::APIBadUserInput.new("Placeholder node not found for reference #{node_id} in way #{self.id.nil? ? placeholder_id : self.id}") if new_id.nil?
         new_id
       else
         node_id