+# == Schema Information
+#
+# Table name: current_relations
+#
+# id :bigint(8) not null, primary key
+# changeset_id :bigint(8) not null
+# timestamp :datetime not null
+# visible :boolean not null
+# version :bigint(8) not null
+#
+# Indexes
+#
+# current_relations_timestamp_idx (timestamp)
+#
+# Foreign Keys
+#
+# current_relations_changeset_id_fkey (changeset_id => changesets.id)
+#
+
class Relation < ActiveRecord::Base
- require 'xml/libxml'
-
- belongs_to :user
+ require "xml/libxml"
- has_many :relation_members, :foreign_key => 'id'
- has_many :relation_tags, :foreign_key => 'id'
+ include ConsistencyValidations
+ include NotRedactable
+ include ObjectMetadata
- has_many :old_relations, :foreign_key => 'id', :order => 'version'
+ self.table_name = "current_relations"
- set_table_name 'current_relations'
+ belongs_to :changeset
- def self.from_xml(xml, create=false)
- begin
- p = XML::Parser.new
- p.string = xml
- doc = p.parse
+ has_many :old_relations, -> { order(:version) }
- relation = Relation.new
+ has_many :relation_members, -> { order(:sequence_id) }
+ has_many :relation_tags
- doc.find('//osm/relation').each do |pt|
- if !create and pt['id'] != '0'
- relation.id = pt['id'].to_i
- end
+ has_many :containing_relation_members, :class_name => "RelationMember", :as => :member
+ has_many :containing_relations, :class_name => "Relation", :through => :containing_relation_members, :source => :relation
- if create
- relation.timestamp = Time.now
- relation.visible = true
- else
- if pt['timestamp']
- relation.timestamp = Time.parse(pt['timestamp'])
- end
- end
+ validates :id, :uniqueness => true, :presence => { :on => :update },
+ :numericality => { :on => :update, :integer_only => true }
+ validates :version, :presence => true,
+ :numericality => { :integer_only => true }
+ validates :changeset_id, :presence => true,
+ :numericality => { :integer_only => true }
+ validates :timestamp, :presence => true
+ validates :changeset, :associated => true
+ validates :visible, :inclusion => [true, false]
- pt.find('tag').each do |tag|
- relation.add_tag_keyval(tag['k'], tag['v'])
- end
+ scope :visible, -> { where(:visible => true) }
+ scope :invisible, -> { where(:visible => false) }
+ scope :nodes, ->(*ids) { joins(:relation_members).where(:current_relation_members => { :member_type => "Node", :member_id => ids.flatten }) }
+ scope :ways, ->(*ids) { joins(:relation_members).where(:current_relation_members => { :member_type => "Way", :member_id => ids.flatten }) }
+ scope :relations, ->(*ids) { joins(:relation_members).where(:current_relation_members => { :member_type => "Relation", :member_id => ids.flatten }) }
- pt.find('member').each do |member|
- relation.add_member(member['type'], member['ref'], member['role'])
- end
- end
- rescue
- relation = nil
+ TYPES = %w[node way relation].freeze
+
+ def self.from_xml(xml, create = false)
+ p = XML::Parser.string(xml, :options => XML::Parser::Options::NOERROR)
+ doc = p.parse
+
+ doc.find("//osm/relation").each do |pt|
+ return Relation.from_xml_node(pt, create)
end
+ raise OSM::APIBadXMLError.new("node", xml, "XML doesn't contain an osm/relation element.")
+ rescue LibXML::XML::Error, ArgumentError => e
+ raise OSM::APIBadXMLError.new("relation", xml, e.message)
+ end
+
+ def self.from_xml_node(pt, create = false)
+ relation = Relation.new
- return relation
+ raise OSM::APIBadXMLError.new("relation", pt, "Version is required when updating") unless create || !pt["version"].nil?
+
+ relation.version = pt["version"]
+ raise OSM::APIBadXMLError.new("relation", pt, "Changeset id is missing") if pt["changeset"].nil?
+
+ relation.changeset_id = pt["changeset"]
+
+ unless create
+ raise OSM::APIBadXMLError.new("relation", pt, "ID is required when updating") if pt["id"].nil?
+
+ relation.id = pt["id"].to_i
+ # .to_i will return 0 if there is no number that can be parsed.
+ # We want to make sure that there is no id with zero anyway
+ raise OSM::APIBadUserInput, "ID of relation cannot be zero when updating." if relation.id.zero?
+ end
+
+ # We don't care about the timestamp nor the visibility as these are either
+ # set explicitly or implicit in the action. The visibility is set to true,
+ # and manually set to false before the actual delete.
+ relation.visible = true
+
+ # Start with no tags
+ relation.tags = {}
+
+ # Add in any tags from the XML
+ pt.find("tag").each do |tag|
+ raise OSM::APIBadXMLError.new("relation", pt, "tag is missing key") if tag["k"].nil?
+ raise OSM::APIBadXMLError.new("relation", pt, "tag is missing value") if tag["v"].nil?
+
+ relation.add_tag_keyval(tag["k"], tag["v"])
+ end
+
+ # need to initialise the relation members array explicitly, as if this
+ # isn't done for a new relation then @members attribute will be nil,
+ # and the members will be loaded from the database instead of being
+ # empty, as intended.
+ relation.members = []
+
+ pt.find("member").each do |member|
+ # member_type =
+ raise OSM::APIBadXMLError.new("relation", pt, "The #{member['type']} is not allowed only, #{TYPES.inspect} allowed") unless TYPES.include? member["type"]
+
+ # member_ref = member['ref']
+ # member_role
+ member["role"] ||= "" # Allow the upload to not include this, in which case we default to an empty string.
+ relation.add_member(member["type"].classify, member["ref"], member["role"])
+ end
+ raise OSM::APIBadUserInput, "Some bad xml in relation" if relation.nil?
+
+ relation
end
def to_xml
doc = OSM::API.new.get_xml_doc
- doc.root << to_xml_node()
- return doc
+ doc.root << to_xml_node
+ doc
end
- def to_xml_node(user_display_name_cache = nil)
- el1 = XML::Node.new 'relation'
- el1['id'] = self.id.to_s
- el1['visible'] = self.visible.to_s
- el1['timestamp'] = self.timestamp.xmlschema
-
- user_display_name_cache = {} if user_display_name_cache.nil?
-
- if user_display_name_cache and user_display_name_cache.key?(self.user_id)
- # use the cache if available
- elsif self.user.data_public?
- user_display_name_cache[self.user_id] = self.user.display_name
- else
- user_display_name_cache[self.user_id] = nil
- end
+ def to_xml_node(changeset_cache = {}, user_display_name_cache = {})
+ el = XML::Node.new "relation"
+ el["id"] = id.to_s
- el1['user'] = user_display_name_cache[self.user_id] unless user_display_name_cache[self.user_id].nil?
-
- self.relation_members.each do |member|
- p=0
- #if visible_members
- # # if there is a list of visible members then use that to weed out deleted segments
- # if visible_members[member.member_type][member.member_id]
- # p=1
- # end
- #else
- # otherwise, manually go to the db to check things
- if member.member.visible?
- p=1
- end
- #end
- if p
- e = XML::Node.new 'member'
- e['type'] = member.member_type
- e['ref'] = member.member_id.to_s
- e['role'] = member.member_role
- el1 << e
- end
- end
+ add_metadata_to_xml_node(el, self, changeset_cache, user_display_name_cache)
- self.relation_tags.each do |tag|
- e = XML::Node.new 'tag'
- e['k'] = tag.k
- e['v'] = tag.v
- el1 << e
+ relation_members.each do |member|
+ member_el = XML::Node.new "member"
+ member_el["type"] = member.member_type.downcase
+ member_el["ref"] = member.member_id.to_s
+ member_el["role"] = member.member_role
+ el << member_el
end
- return el1
- end
- # FIXME is this really needed?
+ add_tags_to_xml_node(el, relation_tags)
+
+ el
+ end
+
+ # FIXME: is this really needed?
def members
- unless @members
- @members = Array.new
- self.relation_members.each do |member|
- @members += [[member.member_type,member.member_id,member.member_role]]
- end
+ @members ||= relation_members.map do |member|
+ [member.member_type, member.member_id, member.member_role]
end
- @members
end
def tags
- unless @tags
- @tags = Hash.new
- self.relation_tags.each do |tag|
- @tags[tag.k] = tag.v
- end
- end
- @tags
+ @tags ||= Hash[relation_tags.collect { |t| [t.k, t.v] }]
end
- def members=(m)
- @members = m
- end
+ attr_writer :members
- def tags=(t)
- @tags = t
- end
+ attr_writer :tags
- def add_member(type,id,role)
- @members = Array.new unless @members
- @members += [[type,id,role]]
+ def add_member(type, id, role)
+ @members ||= []
+ @members << [type, id.to_i, role]
end
def add_tag_keyval(k, v)
- @tags = Hash.new unless @tags
+ @tags ||= {}
+
+ # duplicate tags are now forbidden, so we can't allow values
+ # in the hash to be overwritten.
+ raise OSM::APIDuplicateTagsError.new("relation", id, k) if @tags.include? k
+
@tags[k] = v
end
- def save_with_history!
+ ##
+ # updates the changeset bounding box to contain the bounding box of
+ # the element with given +type+ and +id+. this only works with nodes
+ # and ways at the moment, as they're the only elements to respond to
+ # the :bbox call.
+ def update_changeset_element(type, id)
+ element = Kernel.const_get(type.capitalize).find(id)
+ changeset.update_bbox! element.bbox
+ end
+
+ def delete_with_history!(new_relation, user)
+ raise OSM::APIAlreadyDeletedError.new("relation", new_relation.id) unless visible
+
+ # 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.
+ Relation.transaction do
+ lock!
+ check_consistency(self, new_relation, user)
+ # This will check to see if this relation is used by another relation
+ rel = RelationMember.joins(:relation).find_by("visible = ? AND member_type = 'Relation' and member_id = ? ", true, id)
+ raise OSM::APIPreconditionFailedError, "The relation #{new_relation.id} is used in relation #{rel.relation.id}." unless rel.nil?
+
+ self.changeset_id = new_relation.changeset_id
+ self.tags = {}
+ self.members = []
+ self.visible = false
+ save_with_history!
+ end
+ end
+
+ def update_from(new_relation, user)
Relation.transaction do
- t = Time.now
- self.timestamp = t
- self.save!
+ lock!
+ check_consistency(self, new_relation, user)
+ raise OSM::APIPreconditionFailedError, "Cannot update relation #{id}: data or member data is invalid." unless new_relation.preconditions_ok?(members)
+
+ self.changeset_id = new_relation.changeset_id
+ self.changeset = new_relation.changeset
+ self.tags = new_relation.tags
+ self.members = new_relation.members
+ self.visible = true
+ save_with_history!
+ end
+ end
+
+ def create_with_history(user)
+ check_create_consistency(self, user)
+ raise OSM::APIPreconditionFailedError, "Cannot create relation: data or member data is invalid." unless preconditions_ok?
+
+ self.version = 0
+ self.visible = true
+ save_with_history!
+ end
- tags = self.tags
+ def preconditions_ok?(good_members = [])
+ # These are hastables that store an id in the index of all
+ # the nodes/way/relations that have already been added.
+ # If the member is valid and visible then we add it to the
+ # relevant hash table, with the value true as a cache.
+ # Thus if you have nodes with the ids of 50 and 1 already in the
+ # relation, then the hash table nodes would contain:
+ # => {50=>true, 1=>true}
+ elements = { :node => {}, :way => {}, :relation => {} }
+
+ # pre-set all existing members to good
+ good_members.each { |m| elements[m[0].downcase.to_sym][m[1]] = true }
+
+ members.each do |m|
+ # find the hash for the element type or die
+ hash = elements[m[0].downcase.to_sym]
+ return false unless hash
+
+ # unless its in the cache already
+ next if hash.key? m[1]
+
+ # use reflection to look up the appropriate class
+ model = Kernel.const_get(m[0].capitalize)
+ # get the element with that ID. and, if found, lock the element to
+ # ensure it can't be deleted until after the current transaction
+ # commits.
+ element = model.lock("for share").find_by(:id => m[1])
+
+ # and check that it is OK to use.
+ raise OSM::APIPreconditionFailedError, "Relation with id #{id} cannot be saved due to #{m[0]} with id #{m[1]}" unless element&.visible? && element&.preconditions_ok?
+
+ hash[m[1]] = true
+ end
- RelationTag.delete_all(['id = ?', self.id])
+ true
+ end
- tags.each do |k,v|
- tag = RelationTag.new
- tag.k = k
- tag.v = v
- tag.id = self.id
- tag.save!
+ ##
+ # if any members are referenced by placeholder IDs (i.e: negative) then
+ # this calling this method will fix them using the map from placeholders
+ # to IDs +id_map+.
+ def fix_placeholders!(id_map, placeholder_id = nil)
+ members.map! do |type, id, role|
+ old_id = id.to_i
+ if old_id.negative?
+ new_id = id_map[type.downcase.to_sym][old_id]
+ raise OSM::APIBadUserInput, "Placeholder #{type} not found for reference #{old_id} in relation #{self.id.nil? ? placeholder_id : self.id}." if new_id.nil?
+
+ [type, new_id, role]
+ else
+ [type, id, role]
end
+ end
+ end
- members = self.members
+ private
+
+ def save_with_history!
+ t = Time.now.getutc
+
+ self.version += 1
+ self.timestamp = t
- RelationMember.delete_all(['id = ?', self.id])
+ Relation.transaction do
+ # have to be a little bit clever here - to detect if any tags
+ # changed then we have to monitor their before and after state.
+ tags_changed = false
+
+ # clone the object before saving it so that the original is
+ # still marked as dirty if we retry the transaction
+ clone.save!
+
+ tags = self.tags.clone
+ relation_tags.each do |old_tag|
+ key = old_tag.k
+ # if we can match the tags we currently have to the list
+ # of old tags, then we never set the tags_changed flag. but
+ # if any are different then set the flag and do the DB
+ # update.
+ if tags.key? key
+ tags_changed |= (old_tag.v != tags[key])
+
+ # remove from the map, so that we can expect an empty map
+ # at the end if there are no new tags
+ tags.delete key
+
+ else
+ # this means a tag was deleted
+ tags_changed = true
+ end
+ end
+ # if there are left-over tags then they are new and will have to
+ # be added.
+ tags_changed |= !tags.empty?
+ RelationTag.where(:relation_id => id).delete_all
+ self.tags.each do |k, v|
+ tag = RelationTag.new
+ tag.relation_id = id
+ tag.k = k
+ tag.v = v
+ tag.save!
+ end
+
+ # same pattern as before, but this time we're collecting the
+ # changed members in an array, as the bounding box updates for
+ # elements are per-element, not blanked on/off like for tags.
+ changed_members = []
+ members = self.members.clone
+ relation_members.each do |old_member|
+ key = [old_member.member_type, old_member.member_id, old_member.member_role]
+ i = members.index key
+ if i.nil?
+ changed_members << key
+ else
+ members.delete_at i
+ end
+ end
+ # any remaining members must be new additions
+ changed_members += members
- members.each do |n|
- mem = RelationMember.new
- mem.id = self.id
- mem.member_type = n[0];
- mem.member_id = n[1];
- mem.member_role = n[2];
- mem.save!
+ # update the members. first delete all the old members, as the new
+ # members may be in a different order and i don't feel like implementing
+ # a longest common subsequence algorithm to optimise this.
+ members = self.members
+ RelationMember.where(:relation_id => id).delete_all
+ members.each_with_index do |m, i|
+ mem = RelationMember.new
+ mem.relation_id = id
+ mem.sequence_id = i
+ mem.member_type = m[0]
+ mem.member_id = m[1]
+ mem.member_role = m[2]
+ mem.save!
end
old_relation = OldRelation.from_relation(self)
old_relation.timestamp = t
old_relation.save_with_dependencies!
- end
- end
- def preconditions_ok?
- self.members.each do |m|
- if (m[0] == "node")
- n = Node.find(:first, :conditions => ["id = ?", m[1]])
- unless n and n.visible
- return false
- end
- elsif (m[0] == "way")
- w = Way.find(:first, :conditions => ["id = ?", m[1]])
- unless w and w.visible and w.preconditions_ok?
- return false
- end
- elsif (m[0] == "relation")
- e = Relation.find(:first, :conditions => ["id = ?", m[1]])
- unless e and e.visible and e.preconditions_ok?
- return false
- end
- else
- return false
+ # update the bbox of the changeset and save it too.
+ # discussion on the mailing list gave the following definition for
+ # the bounding box update procedure of a relation:
+ #
+ # adding or removing nodes or ways from a relation causes them to be
+ # added to the changeset bounding box. adding a relation member or
+ # changing tag values causes all node and way members to be added to the
+ # bounding box. this is similar to how the map call does things and is
+ # reasonable on the assumption that adding or removing members doesn't
+ # materially change the rest of the relation.
+ any_relations =
+ changed_members.collect { |type, _id, _role| type == "Relation" }
+ .inject(false) { |acc, elem| acc || elem }
+
+ # if the relation is being deleted tags_changed will be true and members empty
+ # so we need to use changed_members to create a correct bounding box
+ update_members = if visible && (tags_changed || any_relations)
+ # add all non-relation bounding boxes to the changeset
+ # FIXME: check for tag changes along with element deletions and
+ # make sure that the deleted element's bounding box is hit.
+ self.members
+ else
+ changed_members
+ end
+ update_members.each do |type, id, _role|
+ update_changeset_element(type, id) if type != "Relation"
end
+
+ # tell the changeset we updated one element only
+ changeset.add_changes! 1
+
+ # save the (maybe updated) changeset bounding box
+ changeset.save!
end
- return true
- rescue
- return false
end
-
end