-class Changeset < ActiveRecord::Base
- require 'xml/libxml'
+# == Schema Information
+#
+# Table name: changesets
+#
+# id :bigint(8) not null, primary key
+# user_id :bigint(8) not null
+# created_at :datetime not null
+# min_lat :integer
+# max_lat :integer
+# min_lon :integer
+# max_lon :integer
+# closed_at :datetime not null
+# num_changes :integer default(0), not null
+#
+# Indexes
+#
+# changesets_bbox_idx (min_lat,max_lat,min_lon,max_lon) USING gist
+# changesets_closed_at_idx (closed_at)
+# changesets_created_at_idx (created_at)
+# changesets_user_id_created_at_idx (user_id,created_at)
+# changesets_user_id_id_idx (user_id,id)
+# index_changesets_on_user_id_and_closed_at (user_id,closed_at)
+#
+# Foreign Keys
+#
+# changesets_user_id_fkey (user_id => users.id)
+#
+
+class Changeset < ApplicationRecord
+ require "xml/libxml"
+
+ belongs_to :user, :counter_cache => true
+
+ has_many :changeset_tags
- belongs_to :user
-
- has_many :changeset_tags, :foreign_key => 'id'
-
has_many :nodes
has_many :ways
has_many :relations
has_many :old_nodes
has_many :old_ways
has_many :old_relations
-
- validates_presence_of :user_id, :created_at
- validates_inclusion_of :open, :in => [ true, false ]
-
- # over-expansion factor to use when updating the bounding box
- EXPAND = 0.1
+
+ has_many :comments, -> { where(:visible => true).order(:created_at) }, :class_name => "ChangesetComment"
+ has_and_belongs_to_many :subscribers, :class_name => "User", :join_table => "changesets_subscribers", :association_foreign_key => "subscriber_id"
+
+ validates :id, :uniqueness => true, :presence => { :on => :update },
+ :numericality => { :on => :update, :only_integer => true }
+ validates :num_changes, :presence => true,
+ :numericality => { :only_integer => true,
+ :greater_than_or_equal_to => 0 }
+ validates :created_at, :closed_at, :presence => true
+ validates :min_lat, :max_lat, :min_lon, :max_lat, :allow_nil => true,
+ :numericality => { :only_integer => true }
+
+ before_save :update_closed_at
+
+ # maximum number of elements allowed in a changeset
+ MAX_ELEMENTS = 10000
+
+ # maximum time a changeset is allowed to be open for.
+ MAX_TIME_OPEN = 1.day
+
+ # idle timeout increment, one hour seems reasonable.
+ IDLE_TIMEOUT = 1.hour
# Use a method like this, so that we can easily change how we
- # determine whether a changeset is open, without breaking code in at
+ # determine whether a changeset is open, without breaking code in at
# least 6 controllers
- def is_open?
- return open
+ def open?
+ # a changeset is open (that is, it will accept further changes) when
+ # it has not yet run out of time and its capacity is small enough.
+ # note that this may not be a hard limit - due to timing changes and
+ # concurrency it is possible that some changesets may be slightly
+ # longer than strictly allowed or have slightly more changes in them.
+ (closed_at > Time.now.utc) && (num_changes <= MAX_ELEMENTS)
end
- def self.from_xml(xml, create=false)
- begin
- p = XML::Parser.new
- p.string = xml
- doc = p.parse
+ def set_closed_time_now
+ self.closed_at = Time.now.utc if open?
+ end
- cs = Changeset.new
+ 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/changeset")
- doc.find('//osm/changeset').each do |pt|
- if create
- cs.created_at = Time.now
- end
+ if pt
+ Changeset.from_xml_node(pt, :create => create)
+ else
+ raise OSM::APIBadXMLError.new("changeset", xml, "XML doesn't contain an osm/changeset element.")
+ end
+ rescue LibXML::XML::Error, ArgumentError => e
+ raise OSM::APIBadXMLError.new("changeset", xml, e.message)
+ end
- pt.find('tag').each do |tag|
- cs.add_tag_keyval(tag['k'], tag['v'])
- end
- end
- rescue Exception => ex
- cs = nil
+ def self.from_xml_node(pt, create: false)
+ cs = Changeset.new
+ if create
+ cs.created_at = Time.now.utc
+ # initial close time is 1h ahead, but will be increased on each
+ # modification.
+ cs.closed_at = cs.created_at + IDLE_TIMEOUT
+ # initially we have no changes in a changeset
+ cs.num_changes = 0
+ end
+
+ pt.find("tag").each do |tag|
+ raise OSM::APIBadXMLError.new("changeset", pt, "tag is missing key") if tag["k"].nil?
+ raise OSM::APIBadXMLError.new("changeset", pt, "tag is missing value") if tag["v"].nil?
+
+ cs.add_tag_keyval(tag["k"], tag["v"])
end
- return cs
+ cs
end
##
# returns the bounding box of the changeset. it is possible that some
# or all of the values will be nil, indicating that they are undefined.
def bbox
- @bbox ||= [ min_lon, min_lat, max_lon, max_lat ]
+ @bbox ||= BoundingBox.new(min_lon, min_lat, max_lon, max_lat)
+ end
+
+ def bbox_valid?
+ bbox.complete?
end
##
- # expand the bounding box to include the given bounding box. also,
- # expand a little bit more in the direction of the expansion, so that
- # further expansions may be unnecessary. this is an optimisation
- # suggested on the wiki page by kleptog.
- def update_bbox!(array)
- # ensure that bbox is cached and has no nils in it. if there are any
- # nils, just use the bounding box update to write over them.
- @bbox = bbox.zip(array).collect { |a, b| a.nil? ? b : a }
-
- # FIXME - this looks nasty and violates DRY... is there any prettier
- # way to do this?
- @bbox[0] = array[0] + EXPAND * (@bbox[0] - @bbox[2]) if array[0] < @bbox[0]
- @bbox[1] = array[1] + EXPAND * (@bbox[1] - @bbox[3]) if array[1] < @bbox[1]
- @bbox[2] = array[2] + EXPAND * (@bbox[2] - @bbox[0]) if array[2] > @bbox[2]
- @bbox[3] = array[3] + EXPAND * (@bbox[3] - @bbox[1]) if array[3] > @bbox[3]
+ # expand the bounding box to include the given bounding box.
+ def update_bbox!(bbox_update)
+ bbox.expand!(bbox_update)
# update active record. rails 2.1's dirty handling should take care of
# whether this object needs saving or not.
- self.min_lon, self.min_lat, self.max_lon, self.max_lat = @bbox
+ self.min_lon, self.min_lat, self.max_lon, self.max_lat = @bbox.to_a.collect(&:round) if bbox.complete?
end
- def tags_as_hash
- return tags
+ ##
+ # the number of elements is also passed in so that we can ensure that
+ # a single changeset doesn't contain too many elements.
+ def add_changes!(elements)
+ self.num_changes += elements
end
def tags
unless @tags
@tags = {}
- self.changeset_tags.each do |tag|
+ changeset_tags.each do |tag|
@tags[tag.k] = tag.v
end
end
@tags
end
- def tags=(t)
- @tags = t
- end
+ attr_writer :tags
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("changeset", id, k) if @tags.include? k
+
@tags[k] = v
end
def save_with_tags!
- t = Time.now
-
+ # do the changeset update and the changeset tags update in the
+ # same transaction to ensure consistency.
Changeset.transaction do
- # fixme update modified_at time?
- # FIXME there is no modified_at time, should it be added
- self.save!
- end
+ save!
- ChangesetTag.transaction do
tags = self.tags
- ChangesetTag.delete_all(['id = ?', self.id])
+ ChangesetTag.where(:changeset => id).delete_all
- tags.each do |k,v|
+ tags.each do |k, v|
tag = ChangesetTag.new
+ tag.changeset_id = id
tag.k = k
tag.v = v
- tag.id = self.id
tag.save!
end
end
end
-
- def to_xml
- doc = OSM::API.new.get_xml_doc
- doc.root << to_xml_node()
- return doc
+
+ ##
+ # set the auto-close time to be one hour in the future unless
+ # that would make it more than 24h long, in which case clip to
+ # 24h, as this has been decided is a reasonable time limit.
+ def update_closed_at
+ if open?
+ self.closed_at = if (closed_at - created_at) > (MAX_TIME_OPEN - IDLE_TIMEOUT)
+ created_at + MAX_TIME_OPEN
+ else
+ Time.now.utc + IDLE_TIMEOUT
+ end
+ end
end
-
- def to_xml_node(user_display_name_cache = nil)
- el1 = XML::Node.new 'changeset'
- el1['id'] = self.id.to_s
- user_display_name_cache = {} if user_display_name_cache.nil?
+ ##
+ # update this instance from another instance given and the user who is
+ # doing the updating. note that this method is not for updating the
+ # bounding box, only the tags of the changeset.
+ def update_from(other, user)
+ # ensure that only the user who opened the changeset may modify it.
+ raise OSM::APIUserChangesetMismatchError unless user.id == user_id
- 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
+ # can't change a closed changeset
+ raise OSM::APIChangesetAlreadyClosedError, self unless open?
- el1['user'] = user_display_name_cache[self.user_id] unless user_display_name_cache[self.user_id].nil?
+ # copy the other's tags
+ self.tags = other.tags
- self.tags.each do |k,v|
- el2 = XML::Node.new('tag')
- el2['k'] = k.to_s
- el2['v'] = v.to_s
- el1 << el2
- end
-
- el1['created_at'] = self.created_at.xmlschema
- el1['open'] = self.open.to_s
-
- el1['min_lon'] = (bbox[0] / SCALE).to_s unless bbox[0].nil?
- el1['min_lat'] = (bbox[1] / SCALE).to_s unless bbox[1].nil?
- el1['max_lon'] = (bbox[2] / SCALE).to_s unless bbox[2].nil?
- el1['max_lat'] = (bbox[3] / SCALE).to_s unless bbox[3].nil?
-
- # NOTE: changesets don't include the XML of the changes within them,
- # they are just structures for tagging. to get the osmChange of a
- # changeset, see the download method of the controller.
-
- return el1
+ save_with_tags!
end
end