X-Git-Url: https://git.openstreetmap.org./rails.git/blobdiff_plain/db66d47e42bc267670ef00b3b2611b4b53cb40e9..22160b445fefecfc05df263ebeccc1d090c1a9f1:/app/models/way.rb

diff --git a/app/models/way.rb b/app/models/way.rb
index 45789dabe..203d3b703 100644
--- a/app/models/way.rb
+++ b/app/models/way.rb
@@ -1,269 +1,286 @@
-class Way < ActiveRecord::Base
-  require 'xml/libxml'
-
-  set_table_name 'current_ways'
-
-  belongs_to :user
-
-  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'
+# == Schema Information
+#
+# Table name: current_ways
+#
+#  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_ways_timestamp_idx  (timestamp)
+#
+# Foreign Keys
+#
+#  current_ways_changeset_id_fkey  (changeset_id => changesets.id)
+#
+
+class Way < ApplicationRecord
+  require "xml/libxml"
+
+  include ConsistencyValidations
+  include NotRedactable
+
+  self.table_name = "current_ways"
+
+  belongs_to :changeset
+
+  has_many :old_ways, -> { order(:version) }, :inverse_of => :current_way
+
+  has_many :way_nodes, -> { order(:sequence_id) }, :inverse_of => :way
+  has_many :nodes, :through => :way_nodes
+
+  has_many :way_tags
 
   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
-
-  def self.from_xml(xml, create=false)
-    begin
-      p = XML::Parser.new
-      p.string = xml
-      doc = p.parse
-
-      way = Way.new
-
-      doc.find('//osm/way').each do |pt|
-        if !create and pt['id'] != '0'
-          way.id = pt['id'].to_i
-        end
-
-        if create
-          way.timestamp = Time.now
-          way.visible = true
-        else
-          if pt['timestamp']
-            way.timestamp = Time.parse(pt['timestamp'])
-          end
-        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
-      end
-    rescue
-      way = nil
+  has_many :containing_relations, :class_name => "Relation", :through => :containing_relation_members, :source => :relation
+
+  validates :id, :uniqueness => true, :presence => { :on => :update },
+                 :numericality => { :on => :update, :only_integer => true }
+  validates :version, :presence => true,
+                      :numericality => { :only_integer => true }
+  validates :timestamp, :presence => true
+  validates :changeset, :associated => true
+  validates :visible, :inclusion => [true, false]
+
+  scope :visible, -> { where(:visible => true) }
+  scope :invisible, -> { where(:visible => false) }
+
+  # Read in xml as text and return it's Way object representation
+  def self.from_xml(xml, create: false)
+    p = XML::Parser.string(xml, :options => XML::Parser::Options::NOERROR)
+    doc = p.parse
+    pt = doc.find_first("//osm/way")
+
+    if pt
+      Way.from_xml_node(pt, :create => create)
+    else
+      raise OSM::APIBadXMLError.new("node", xml, "XML doesn't contain an osm/way element.")
     end
-
-    return way
+  rescue LibXML::XML::Error, ArgumentError => e
+    raise OSM::APIBadXMLError.new("way", xml, e.message)
   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
+  def self.from_xml_node(pt, create: false)
+    way = Way.new
 
-  # 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
+    raise OSM::APIBadXMLError.new("way", pt, "Version is required when updating") unless create || !pt["version"].nil?
 
-  def to_xml_node(visible_nodes = nil, user_display_name_cache = nil)
-    el1 = XML::Node.new 'way'
-    el1['id'] = self.id.to_s
-    el1['visible'] = self.visible.to_s
-    el1['timestamp'] = self.timestamp.xmlschema
+    way.version = pt["version"]
+    raise OSM::APIBadXMLError.new("way", pt, "Changeset id is missing") if pt["changeset"].nil?
 
-    user_display_name_cache = {} if user_display_name_cache.nil?
+    way.changeset_id = pt["changeset"]
 
-    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
+    unless create
+      raise OSM::APIBadXMLError.new("way", pt, "ID is required when updating") if pt["id"].nil?
+
+      way.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 way cannot be zero when updating." if way.id.zero?
     end
 
-    el1['user'] = user_display_name_cache[self.user_id] unless user_display_name_cache[self.user_id].nil?
+    # 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.
+    way.visible = true
 
-    # 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.visible? and nd.node.visible?
-          ordered_nodes[nd.sequence_id] = nd.node_id.to_s
-        end
-      end
-    end
+    # Start with no tags
+    way.tags = {}
 
-    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
+    # Add in any tags from the XML
+    pt.find("tag").each do |tag|
+      raise OSM::APIBadXMLError.new("way", pt, "tag is missing key") if tag["k"].nil?
+      raise OSM::APIBadXMLError.new("way", pt, "tag is missing value") if tag["v"].nil?
 
-    self.way_tags.each do |tag|
-      e = XML::Node.new 'tag'
-      e['k'] = tag.k
-      e['v'] = tag.v
-      el1 << e
+      way.add_tag_keyval(tag["k"], tag["v"])
     end
-    return el1
-  end 
 
-  def nds
-    unless @nds
-      @nds = Array.new
-      self.way_nodes.each do |nd|
-        @nds += [nd.node_id]
-      end
+    pt.find("nd").each do |nd|
+      way.add_nd_num(nd["ref"])
     end
-    @nds
-  end
 
-  def tags
-    unless @tags
-      @tags = {}
-      self.way_tags.each do |tag|
-        @tags[tag.k] = tag.v
-      end
-    end
-    @tags
+    way
   end
 
-  def nds=(s)
-    @nds = s
+  def nds
+    @nds ||= way_nodes.collect(&:node_id)
   end
 
-  def tags=(t)
-    @tags = t
+  def tags
+    @tags ||= way_tags.to_h { |t| [t.k, t.v] }
   end
 
+  attr_writer :nds, :tags
+
   def add_nd_num(n)
-    @nds = Array.new unless @nds
+    @nds ||= []
     @nds << n.to_i
   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("way", id, k) if @tags.include? k
+
     @tags[k] = v
   end
 
-  def save_with_history!
-    t = Time.now
+  ##
+  # the integer coords (i.e: unscaled) bounding box of the way, assuming
+  # straight line segments.
+  def bbox
+    lons = nodes.collect(&:longitude)
+    lats = nodes.collect(&:latitude)
+    BoundingBox.new(lons.min, lats.min, lons.max, lats.max)
+  end
 
+  def update_from(new_way, user)
     Way.transaction do
-      self.timestamp = t
-      self.save!
+      lock!
+      check_update_element_consistency(self, new_way, user)
+      raise OSM::APIPreconditionFailedError, "Cannot update way #{id}: data is invalid." unless new_way.preconditions_ok?(nds)
+
+      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
+  end
 
-    WayTag.transaction do
-      tags = self.tags
+  def create_with_history(user)
+    check_create_element_consistency(self, user)
+    raise OSM::APIPreconditionFailedError, "Cannot create way: data is invalid." unless preconditions_ok?
 
-      WayTag.delete_all(['id = ?', self.id])
+    self.version = 0
+    self.visible = true
+    save_with_history!
+  end
 
-      tags.each do |k,v|
-        tag = WayTag.new
-        tag.k = k
-        tag.v = v
-        tag.id = self.id
-        tag.save!
-      end
-    end
+  def preconditions_ok?(old_nodes = [])
+    return false if nds.empty?
+    raise OSM::APITooManyWayNodesError.new(id, nds.length, Settings.max_number_of_way_nodes) if nds.length > Settings.max_number_of_way_nodes
 
-    WayNode.transaction do
-      nds = self.nds
+    # 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 = (nds - old_nodes).sort.uniq
 
-      WayNode.delete_all(['id = ?', self.id])
+    unless new_nds.empty?
+      # NOTE: nodes are locked here to ensure they can't be deleted before
+      # the current transaction commits.
+      db_nds = Node.where(:id => new_nds, :visible => true).lock("for share")
 
-      sequence = 1
-      nds.each do |n|
-        nd = WayNode.new
-        nd.id = [self.id, sequence]
-        nd.node_id = n
-        nd.save!
-        sequence += 1
+      if db_nds.length < new_nds.length
+        missing = new_nds - db_nds.collect(&:id)
+        raise OSM::APIPreconditionFailedError, "Way #{id} requires the nodes with id in (#{missing.join(',')}), which either do not exist, or are not visible."
       end
     end
 
-    old_way = OldWay.from_way(self)
-    old_way.timestamp = t
-    old_way.save_with_dependencies!
+    true
   end
 
-  def preconditions_ok?
-    return false if self.nds.empty?
-    self.nds.each do |n|
-      node = Node.find(:first, :conditions => ["id = ?", n])
-      unless node and node.visible
-        return false
-      end
+  def delete_with_history!(new_way, user)
+    raise OSM::APIAlreadyDeletedError.new("way", new_way.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.
+    Way.transaction do
+      lock!
+      check_update_element_consistency(self, new_way, user)
+      rels = Relation.joins(:relation_members).where(:visible => true, :current_relation_members => { :member_type => "Way", :member_id => id }).order(:id)
+      raise OSM::APIPreconditionFailedError, "Way #{id} is still used by relations #{rels.collect(&:id).join(',')}." unless rels.empty?
+
+      self.changeset_id = new_way.changeset_id
+      self.changeset = new_way.changeset
+
+      self.tags = []
+      self.nds = []
+      self.visible = false
+      save_with_history!
     end
-    return true
   end
 
-  # Delete the way and it's relations, but don't really delete it - set its visibility to false and update the history etc to maintain wiki-like functionality.
-  def delete_with_relations_and_history(user)
-    if self.visible
-	  # FIXME
-	  # this should actually delete the relations,
-	  # not just throw a PreconditionFailed if it's a member of a relation!!
-      if RelationMember.find(:first, :joins => "INNER JOIN current_relations ON current_relations.id=current_relation_members.id",
-                             :conditions => [ "visible = 1 AND member_type='way' and member_id=?", self.id])
-        raise OSM::APIPreconditionFailedError
-      # end FIXME
+  ##
+  # 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)
+    nds.map! do |node_id|
+      if node_id.negative?
+        new_id = id_map[:node][node_id]
+        raise OSM::APIBadUserInput, "Placeholder node not found for reference #{node_id} in way #{id.nil? ? placeholder_id : id}" if new_id.nil?
+
+        new_id
       else
-        self.user_id = user.id
-        self.tags = []
-        self.nds = []
-        self.visible = false
-        self.save_with_history!
+        node_id
       end
-    else
-      raise OSM::APIAlreadyDeletedError
     end
   end
 
-  # delete a way and it's nodes that aren't part of other ways, with history
-  def delete_with_relations_and_nodes_and_history(user)
-    node_ids_to_delete = node_ids - node_ids_not_to_delete
+  private
 
-    # delete the nodes not used by other ways
-    self.unshared_node_ids.each do |node_id|
-      n = Node.find(node_id)
-      n.user_id = user.id
-      n.visible = false
-      n.save_with_history!
-    end
-    
-    self.user_id = user.id
+  def save_with_history!
+    t = Time.now.utc
 
-    self.delete_with_relations_and_history(user)
-  end
+    self.version += 1
+    self.timestamp = t
 
-  # Find nodes that belong to this way only
-  def unshared_node_ids
-    node_ids = self.nodes.collect { |node| node.id }
+    # 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 = changeset
+    cs.update_bbox!(bbox) unless nodes.empty?
 
-    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
+    Way.transaction do
+      # clone the object before saving it so that the original is
+      # still marked as dirty if we retry the transaction
+      clone.save!
 
-    return node_ids
-  end
+      tags = self.tags
+      WayTag.where(:way_id => id).delete_all
+      tags.each do |k, v|
+        tag = WayTag.new
+        tag.way_id = id
+        tag.k = k
+        tag.v = v
+        tag.save!
+      end
 
-  # Temporary method to match interface to nodes
-  def tags_as_hash
-    return self.tags
+      nds = self.nds
+      WayNode.where(:way_id => id).delete_all
+      sequence = 1
+      nds.each do |n|
+        nd = WayNode.new
+        nd.id = [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.
+      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