+ # Extract the arguments
+ id = params[:id].to_i
+
+ # Find the changeset and check it is valid
+ changeset = Changeset.find(id)
+ raise OSM::APIChangesetNotYetClosedError.new(changeset) if changeset.is_open?
+ raise OSM::APIChangesetAlreadySubscribedError.new(changeset) if changeset.subscribers.exists?(@user)
+
+ # Add the subscriber
+ changeset.subscribers << @user
+
+ # Return a copy of the updated changeset
+ render :text => changeset.to_xml.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # Removes a subscriber from the changeset
+ def unsubscribe
+ # Check the arguments are sane
+ raise OSM::APIBadUserInput.new("No id was given") unless params[:id]
+
+ # Extract the arguments
+ id = params[:id].to_i
+
+ # Find the changeset and check it is valid
+ changeset = Changeset.find(id)
+ raise OSM::APIChangesetNotYetClosedError.new(changeset) if changeset.is_open?
+ raise OSM::APIChangesetNotSubscribedError.new(changeset) unless changeset.subscribers.exists?(@user)
+
+ # Remove the subscriber
+ changeset.subscribers.delete(@user)
+
+ # Return a copy of the updated changeset
+ render :text => changeset.to_xml.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # Sets visible flag on comment to false
+ def hide_comment
+ # Check the arguments are sane
+ raise OSM::APIBadUserInput.new("No id was given") unless params[:id]
+
+ # Extract the arguments
+ id = params[:id].to_i
+
+ # Find the changeset
+ comment = ChangesetComment.find(id)
+
+ # Hide the comment
+ comment.update(:visible => false)
+
+ # Return a copy of the updated changeset
+ render :text => comment.changeset.to_xml.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # Sets visible flag on comment to true
+ def unhide_comment
+ # Check the arguments are sane
+ raise OSM::APIBadUserInput.new("No id was given") unless params[:id]
+
+ # Extract the arguments
+ id = params[:id].to_i
+
+ # Find the changeset
+ comment = ChangesetComment.find(id)
+
+ # Unhide the comment
+ comment.update(:visible => true)
+
+ # Return a copy of the updated changeset
+ render :text => comment.changeset.to_xml.to_s, :content_type => "text/xml"
+ end
+
+ ##
+ # Get a feed of recent changeset comments
+ def comments_feed
+ if params[:id]
+ # Extract the arguments
+ id = params[:id].to_i
+
+ # Find the changeset
+ changeset = Changeset.find(id)
+
+ # Return comments for this changeset only
+ @comments = changeset.comments.includes(:author, :changeset).limit(comments_limit)
+ else
+ # Return comments
+ @comments = ChangesetComment.includes(:author, :changeset).where(:visible => :true).order("created_at DESC").limit(comments_limit).preload(:changeset)
+ end
+
+ # Render the result
+ respond_to do |format|
+ format.rss
+ end
+ end
+
+private
+ #------------------------------------------------------------
+ # utility functions below.
+ #------------------------------------------------------------
+
+ ##
+ # if a bounding box was specified do some sanity checks.
+ # restrict changesets to those enclosed by a bounding box
+ # we need to return both the changesets and the bounding box
+ def conditions_bbox(changesets, bbox)
+ if bbox
+ bbox.check_boundaries
+ bbox = bbox.to_scaled
+ return changesets.where("min_lon < ? and max_lon > ? and min_lat < ? and max_lat > ?",
+ bbox.max_lon.to_i, bbox.min_lon.to_i,
+ bbox.max_lat.to_i, bbox.min_lat.to_i)
+ else
+ return changesets
+ end
+ end
+
+ ##
+ # restrict changesets to those by a particular user
+ def conditions_user(changesets, user, name)
+ unless user.nil? and name.nil?
+ # shouldn't provide both name and UID
+ raise OSM::APIBadUserInput.new("provide either the user ID or display name, but not both") if user and name
+
+ # use either the name or the UID to find the user which we're selecting on.
+ u = if name.nil?
+ # user input checking, we don't have any UIDs < 1
+ raise OSM::APIBadUserInput.new("invalid user ID") if user.to_i < 1
+ u = User.find(user.to_i)
+ else
+ u = User.find_by_display_name(name)
+ end
+
+ # make sure we found a user
+ raise OSM::APINotFoundError.new if u.nil?
+
+ # should be able to get changesets of public users only, or
+ # our own changesets regardless of public-ness.
+ unless u.data_public?
+ # get optional user auth stuff so that users can see their own
+ # changesets if they're non-public
+ setup_user_auth
+
+ raise OSM::APINotFoundError if @user.nil? or @user.id != u.id
+ end
+ return changesets.where(:user_id => u.id)
+ else
+ return changesets
+ end
+ end
+
+ ##
+ # restrict changes to those closed during a particular time period
+ def conditions_time(changesets, time)
+ unless time.nil?
+ # if there is a range, i.e: comma separated, then the first is
+ # low, second is high - same as with bounding boxes.
+ if time.count(',') == 1
+ # check that we actually have 2 elements in the array
+ times = time.split(/,/)
+ raise OSM::APIBadUserInput.new("bad time range") if times.size != 2
+
+ from, to = times.collect { |t| DateTime.parse(t) }
+ return changesets.where("closed_at >= ? and created_at <= ?", from, to)
+ else
+ # if there is no comma, assume its a lower limit on time
+ return changesets.where("closed_at >= ?", DateTime.parse(time))
+ end
+ else
+ return changesets
+ end
+ # stupid DateTime seems to throw both of these for bad parsing, so
+ # we have to catch both and ensure the correct code path is taken.
+ rescue ArgumentError => ex
+ raise OSM::APIBadUserInput.new(ex.message.to_s)
+ rescue RuntimeError => ex
+ raise OSM::APIBadUserInput.new(ex.message.to_s)
+ end
+
+ ##
+ # return changesets which are open (haven't been closed yet)
+ # we do this by seeing if the 'closed at' time is in the future. Also if we've
+ # hit the maximum number of changes then it counts as no longer open.
+ # if parameter 'open' is nill then open and closed changesets are returned
+ def conditions_open(changesets, open)
+ if open.nil?
+ return changesets
+ else
+ return changesets.where("closed_at >= ? and num_changes <= ?",
+ Time.now.getutc, Changeset::MAX_ELEMENTS)
+ end
+ end
+
+ ##
+ # query changesets which are closed
+ # ('closed at' time has passed or changes limit is hit)
+ def conditions_closed(changesets, closed)
+ if closed.nil?
+ return changesets
+ else
+ return changesets.where("closed_at < ? or num_changes > ?",
+ Time.now.getutc, Changeset::MAX_ELEMENTS)
+ end
+ end
+
+ ##
+ # query changesets by a list of ids
+ # (either specified as array or comma-separated string)
+ def conditions_ids(changesets, ids)
+ if ids.nil?
+ return changesets
+ elsif ids.empty?
+ raise OSM::APIBadUserInput.new("No changesets were given to search for")
+ else
+ ids = ids.split(',').collect { |n| n.to_i }
+ return changesets.where(:id => ids)
+ end
+ end
+
+ ##
+ # eliminate empty changesets (where the bbox has not been set)
+ # this should be applied to all changeset list displays
+ def conditions_nonempty(changesets)
+ return changesets.where("num_changes > 0")
+ end
+
+ ##
+ # Get the maximum number of comments to return
+ def comments_limit
+ if params[:limit]
+ if params[:limit].to_i > 0 and params[:limit].to_i <= 10000
+ params[:limit].to_i
+ else
+ raise OSM::APIBadUserInput.new("Comments limit must be between 1 and 10000")
+ end
+ else
+ 100
+ end