openstreetmap-website/app/models/way.rb

359 lines
9.9 KiB
Ruby

class Way < ActiveRecord::Base
require 'xml/libxml'
include ConsistencyValidations
set_table_name 'current_ways'
belongs_to :changeset
has_many :old_ways, :foreign_key => 'id', :order => 'version'
has_many :way_nodes, :foreign_key => 'id', :order => 'sequence_id'
has_many :nodes, :through => :way_nodes, :order => 'sequence_id'
has_many :way_tags, :foreign_key => 'id'
has_many :containing_relation_members, :class_name => "RelationMember", :as => :member
has_many :containing_relations, :class_name => "Relation", :through => :containing_relation_members, :source => :relation, :extend => ObjectFinder
validates_presence_of :id, :on => :update
validates_presence_of :changeset_id,:version, :timestamp
validates_uniqueness_of :id
validates_inclusion_of :visible, :in => [ true, false ]
validates_numericality_of :changeset_id, :version, :integer_only => true
validates_numericality_of :id, :on => :update, :integer_only => true
validates_associated :changeset
def self.from_xml(xml, create=false)
begin
p = XML::Parser.string(xml)
doc = p.parse
doc.find('//osm/way').each do |pt|
return Way.from_xml_node(pt, create)
end
rescue LibXML::XML::Error, ArgumentError => ex
raise OSM::APIBadXMLError.new("way", xml, ex.message)
end
end
def self.from_xml_node(pt, create=false)
way = Way.new
if !create and pt['id'] != '0'
way.id = pt['id'].to_i
end
way.version = pt['version']
raise OSM::APIBadXMLError.new("node", pt, "Changeset is required") if pt['changeset'].nil?
way.changeset_id = pt['changeset']
# This next section isn't required for the create, update, or delete of ways
if create
way.timestamp = Time.now.getutc
way.visible = true
else
if pt['timestamp']
way.timestamp = Time.parse(pt['timestamp'])
end
# if visible isn't present then it defaults to true
way.visible = (pt['visible'] or true)
end
pt.find('tag').each do |tag|
way.add_tag_keyval(tag['k'], tag['v'])
end
pt.find('nd').each do |nd|
way.add_nd_num(nd['ref'])
end
return way
end
# Find a way given it's ID, and in a single SQL call also grab its nodes
#
# You can't pull in all the tags too unless we put a sequence_id on the way_tags table and have a multipart key
def self.find_eager(id)
way = Way.find(id, :include => {:way_nodes => :node})
#If waytag had a multipart key that was real, you could do this:
#way = Way.find(id, :include => [:way_tags, {:way_nodes => :node}])
end
# Find a way given it's ID, and in a single SQL call also grab its nodes and tags
def to_xml
doc = OSM::API.new.get_xml_doc
doc.root << to_xml_node()
return doc
end
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
el1['timestamp'] = self.timestamp.xmlschema
el1['version'] = self.version.to_s
el1['changeset'] = self.changeset_id.to_s
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[user_id] = self.changeset.user.display_name
else
user_display_name_cache[user_id] = nil
end
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
ordered_nodes = []
self.way_nodes.each do |nd|
if visible_nodes
# if there is a list of visible nodes then use that to weed out deleted nodes
if visible_nodes[nd.node_id]
ordered_nodes[nd.sequence_id] = nd.node_id.to_s
end
else
# otherwise, manually go to the db to check things
if nd.node and nd.node.visible?
ordered_nodes[nd.sequence_id] = nd.node_id.to_s
end
end
end
ordered_nodes.each do |nd_id|
if nd_id and nd_id != '0'
e = XML::Node.new 'nd'
e['ref'] = nd_id
el1 << e
end
end
self.way_tags.each do |tag|
e = XML::Node.new 'tag'
e['k'] = tag.k
e['v'] = tag.v
el1 << e
end
return el1
end
def nds
unless @nds
@nds = Array.new
self.way_nodes.each do |nd|
@nds += [nd.node_id]
end
end
@nds
end
def tags
unless @tags
@tags = {}
self.way_tags.each do |tag|
@tags[tag.k] = tag.v
end
end
@tags
end
def nds=(s)
@nds = s
end
def tags=(t)
@tags = t
end
def add_nd_num(n)
@nds = Array.new unless @nds
@nds << n.to_i
end
def add_tag_keyval(k, v)
@tags = Hash.new unless @tags
# duplicate tags are now forbidden, so we can't allow values
# in the hash to be overwritten.
raise OSM::APIDuplicateTagsError.new("way", self.id, k) if @tags.include? k
@tags[k] = v
end
##
# the integer coords (i.e: unscaled) bounding box of the way, assuming
# straight line segments.
def bbox
lons = nodes.collect { |n| n.longitude }
lats = nodes.collect { |n| n.latitude }
[ lons.min, lats.min, lons.max, lats.max ]
end
def update_from(new_way, user)
check_consistency(self, new_way, user)
unless new_way.preconditions_ok?
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
def create_with_history(user)
check_create_consistency(self, user)
unless self.preconditions_ok?
raise OSM::APIPreconditionFailedError.new("Cannot create way: data is invalid.")
end
self.version = 0
self.visible = true
save_with_history!
end
def preconditions_ok?
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")
end
end
return true
end
def delete_with_history!(new_way, user)
unless self.visible
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
check_consistency(self, new_way, user)
if RelationMember.find(:first, :joins => "INNER JOIN current_relations ON current_relations.id=current_relation_members.id",
: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
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
end
##
# 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, placeholder_id = nil)
self.nds.map! do |node_id|
if node_id < 0
new_id = id_map[:node][node_id]
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
end
end
end
private
def save_with_history!
t = Time.now.getutc
# update the bounding box, note that this has to be done both before
# and after the save, so that nodes from both versions are included in the
# bbox. we use a copy of the changeset so that it isn't reloaded
# later in the save.
cs = self.changeset
cs.update_bbox!(bbox) unless nodes.empty?
Way.transaction do
self.version += 1
self.timestamp = t
self.save!
tags = self.tags
WayTag.delete_all(['id = ?', self.id])
tags.each do |k,v|
tag = WayTag.new
tag.k = k
tag.v = v
tag.id = self.id
tag.save!
end
nds = self.nds
WayNode.delete_all(['id = ?', self.id])
sequence = 1
nds.each do |n|
nd = WayNode.new
nd.id = [self.id, sequence]
nd.node_id = n
nd.save!
sequence += 1
end
old_way = OldWay.from_way(self)
old_way.timestamp = t
old_way.save_with_dependencies!
# reload the way so that the nodes array points to the correct
# new set of nodes.
self.reload
# update and commit the bounding box, now that way nodes
# have been updated and we're in a transaction.
cs.update_bbox!(bbox) unless nodes.empty?
# tell the changeset we updated one element only
cs.add_changes! 1
cs.save!
end
end
end