+ assert_method :put
+
+ cs = Changeset.from_xml(request.raw_post, true)
+
+ # Assume that Changeset.from_xml has thrown an exception if there is an error parsing the xml
+ cs.user_id = @user.id
+ cs.save_with_tags!
+ render :text => cs.id.to_s, :content_type => "text/plain"
+ end
+
+ ##
+ # Return XML giving the basic info about the changeset. Does not
+ # return anything about the nodes, ways and relations in the changeset.
+ def read
+ changeset = Changeset.find(params[:id])
+ render :text => changeset.to_xml.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # marks a changeset as closed. this may be called multiple times
+ # on the same changeset, so is idempotent.
+ def close
+ assert_method :put
+
+ changeset = Changeset.find(params[:id])
+ check_changeset_consistency(changeset, @user)
+
+ # to close the changeset, we'll just set its closed_at time to
+ # now. this might not be enough if there are concurrency issues,
+ # but we'll have to wait and see.
+ changeset.set_closed_time_now
+
+ changeset.save!
+ render :nothing => true
+ end
+
+ ##
+ # insert a (set of) points into a changeset bounding box. this can only
+ # increase the size of the bounding box. this is a hint that clients can
+ # set either before uploading a large number of changes, or changes that
+ # the client (but not the server) knows will affect areas further away.
+ def expand_bbox
+ # only allow POST requests, because although this method is
+ # idempotent, there is no "document" to PUT really...
+ assert_method :post
+
+ cs = Changeset.find(params[:id])
+ check_changeset_consistency(cs, @user)
+
+ # keep an array of lons and lats
+ lon = Array.new
+ lat = Array.new
+
+ # the request is in pseudo-osm format... this is kind-of an
+ # abuse, maybe should change to some other format?
+ doc = XML::Parser.string(request.raw_post).parse
+ doc.find("//osm/node").each do |n|
+ lon << n['lon'].to_f * GeoRecord::SCALE
+ lat << n['lat'].to_f * GeoRecord::SCALE
+ end
+
+ # add the existing bounding box to the lon-lat array
+ lon << cs.min_lon unless cs.min_lon.nil?
+ lat << cs.min_lat unless cs.min_lat.nil?
+ lon << cs.max_lon unless cs.max_lon.nil?
+ lat << cs.max_lat unless cs.max_lat.nil?
+
+ # collapse the arrays to minimum and maximum
+ cs.min_lon, cs.min_lat, cs.max_lon, cs.max_lat =
+ lon.min, lat.min, lon.max, lat.max
+
+ # save the larger bounding box and return the changeset, which
+ # will include the bigger bounding box.
+ cs.save!
+ render :text => cs.to_xml.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # Upload a diff in a single transaction.
+ #
+ # This means that each change within the diff must succeed, i.e: that
+ # each version number mentioned is still current. Otherwise the entire
+ # transaction *must* be rolled back.
+ #
+ # Furthermore, each element in the diff can only reference the current
+ # changeset.
+ #
+ # Returns: a diffResult document, as described in
+ # http://wiki.openstreetmap.org/wiki/OSM_Protocol_Version_0.6
+ def upload
+ # only allow POST requests, as the upload method is most definitely
+ # not idempotent, as several uploads with placeholder IDs will have
+ # different side-effects.
+ # see http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.1.2
+ assert_method :post
+
+ changeset = Changeset.find(params[:id])
+ check_changeset_consistency(changeset, @user)
+
+ diff_reader = DiffReader.new(request.raw_post, changeset)
+ Changeset.transaction do
+ result = diff_reader.commit
+ render :text => result.to_s, :content_type => "text/xml"
+ end
+ end
+
+ ##
+ # download the changeset as an osmChange document.
+ #
+ # to make it easier to revert diffs it would be better if the osmChange
+ # format were reversible, i.e: contained both old and new versions of
+ # modified elements. but it doesn't at the moment...
+ #
+ # this method cannot order the database changes fully (i.e: timestamp and
+ # version number may be too coarse) so the resulting diff may not apply
+ # to a different database. however since changesets are not atomic this
+ # behaviour cannot be guaranteed anyway and is the result of a design
+ # choice.
+ def download
+ changeset = Changeset.find(params[:id])
+
+ # get all the elements in the changeset which haven't been redacted
+ # and stick them in a big array.
+ elements = [changeset.old_nodes.unredacted,
+ changeset.old_ways.unredacted,
+ changeset.old_relations.unredacted].flatten
+
+ # sort the elements by timestamp and version number, as this is the
+ # almost sensible ordering available. this would be much nicer if
+ # global (SVN-style) versioning were used - then that would be
+ # unambiguous.
+ elements.sort! do |a, b|
+ if (a.timestamp == b.timestamp)
+ a.version <=> b.version
+ else
+ a.timestamp <=> b.timestamp
+ end
+ end
+
+ # create an osmChange document for the output
+ result = OSM::API.new.get_xml_doc
+ result.root.name = "osmChange"
+
+ # generate an output element for each operation. note: we avoid looking
+ # at the history because it is simpler - but it would be more correct to
+ # check these assertions.
+ elements.each do |elt|
+ result.root <<
+ if (elt.version == 1)
+ # first version, so it must be newly-created.
+ created = XML::Node.new "create"
+ created << elt.to_xml_node
+ else
+ unless elt.visible
+ # if the element isn't visible then it must have been deleted
+ deleted = XML::Node.new "delete"
+ deleted << elt.to_xml_node
+ else
+ # must be a modify
+ modified = XML::Node.new "modify"
+ modified << elt.to_xml_node
+ end
+ end
+ end
+
+ render :text => result.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # query changesets by bounding box, time, user or open/closed status.
+ def query
+ # find any bounding box
+ if params['bbox']
+ bbox = BoundingBox.from_bbox_params(params)
+ end
+
+ # create the conditions that the user asked for. some or all of
+ # these may be nil.
+ changesets = Changeset.scoped
+ changesets = conditions_bbox(changesets, bbox)
+ changesets = conditions_user(changesets, params['user'], params['display_name'])
+ changesets = conditions_time(changesets, params['time'])
+ changesets = conditions_open(changesets, params['open'])
+ changesets = conditions_closed(changesets, params['closed'])
+
+ # create the results document
+ results = OSM::API.new.get_xml_doc
+
+ # add all matching changesets to the XML results document
+ changesets.order("created_at DESC").limit(100).each do |cs|
+ results.root << cs.to_xml_node
+ end
+
+ render :text => results.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # updates a changeset's tags. none of the changeset's attributes are
+ # user-modifiable, so they will be ignored.
+ #
+ # changesets are not (yet?) versioned, so we don't have to deal with
+ # history tables here. changesets are locked to a single user, however.
+ #
+ # after succesful update, returns the XML of the changeset.
+ def update
+ # request *must* be a PUT.
+ assert_method :put
+
+ changeset = Changeset.find(params[:id])
+ new_changeset = Changeset.from_xml(request.raw_post)
+
+ unless new_changeset.nil?
+ check_changeset_consistency(changeset, @user)
+ changeset.update_from(new_changeset, @user)
+ render :text => changeset.to_xml, :mime_type => "text/xml"
+ else
+
+ render :nothing => true, :status => :bad_request
+ end
+ end
+
+ ##
+ # list edits (open changesets) in reverse chronological order
+ def list
+ if request.format == :atom and params[:page]
+ redirect_to params.merge({ :page => nil }), :status => :moved_permanently
+ else
+ changesets = conditions_nonempty(Changeset.scoped)
+
+ if params[:display_name]
+ user = User.find_by_display_name(params[:display_name])
+
+ if user and user.active?
+ if user.data_public? or user == @user
+ changesets = changesets.where(:user_id => user.id)
+ else
+ changesets = changesets.where("false")
+ end
+ else
+ render_unknown_user params[:display_name]
+ return
+ end
+ end
+
+ if params[:friends]
+ if @user
+ changesets = changesets.where(:user_id => @user.friend_users.public)
+ elsif request.format == :html
+ require_user
+ return
+ end
+ end
+
+ if params[:nearby]
+ if @user
+ changesets = changesets.where(:user_id => @user.nearby)
+ elsif request.format == :html
+ require_user
+ return
+ end
+ end
+
+ if params[:bbox]
+ bbox = BoundingBox.from_bbox_params(params)
+ elsif params[:minlon] and params[:minlat] and params[:maxlon] and params[:maxlat]
+ bbox = BoundingBox.from_lon_lat_params(params)
+ end