1 # The ChangesetController is the RESTful interface to Changeset objects
4 class ChangesetsController < ApiController
8 before_action :authorize, :only => [:create, :update, :upload, :close, :subscribe, :unsubscribe]
9 before_action :api_deny_access_handler, :only => [:create, :update, :upload, :close, :subscribe, :unsubscribe, :expand_bbox]
13 before_action :require_public_data, :only => [:create, :update, :upload, :close, :subscribe, :unsubscribe]
14 before_action :check_api_writable, :only => [:create, :update, :upload, :subscribe, :unsubscribe]
15 before_action :check_api_readable, :except => [:create, :update, :upload, :download, :query, :subscribe, :unsubscribe]
16 before_action(:only => [:index, :feed]) { |c| c.check_database_readable(true) }
17 around_action :api_call_handle_error
18 around_action :api_call_timeout, :except => [:upload]
20 # Helper methods for checking consistency
21 include ConsistencyValidations
23 # Create a changeset from XML.
27 cs = Changeset.from_xml(request.raw_post, true)
29 # Assume that Changeset.from_xml has thrown an exception if there is an error parsing the xml
30 cs.user = current_user
33 # Subscribe user to changeset comments
34 cs.subscribers << current_user
36 render :plain => cs.id.to_s
40 # Return XML giving the basic info about the changeset. Does not
41 # return anything about the nodes, ways and relations in the changeset.
43 @changeset = Changeset.find(params[:id])
44 @include_discussion = params[:include_discussion].presence
49 # marks a changeset as closed. this may be called multiple times
50 # on the same changeset, so is idempotent.
54 changeset = Changeset.find(params[:id])
55 check_changeset_consistency(changeset, current_user)
57 # to close the changeset, we'll just set its closed_at time to
58 # now. this might not be enough if there are concurrency issues,
59 # but we'll have to wait and see.
60 changeset.set_closed_time_now
67 # insert a (set of) points into a changeset bounding box. this can only
68 # increase the size of the bounding box. this is a hint that clients can
69 # set either before uploading a large number of changes, or changes that
70 # the client (but not the server) knows will affect areas further away.
72 # only allow POST requests, because although this method is
73 # idempotent, there is no "document" to PUT really...
76 cs = Changeset.find(params[:id])
77 check_changeset_consistency(cs, current_user)
79 # keep an array of lons and lats
83 # the request is in pseudo-osm format... this is kind-of an
84 # abuse, maybe should change to some other format?
85 doc = XML::Parser.string(request.raw_post, :options => XML::Parser::Options::NOERROR).parse
86 doc.find("//osm/node").each do |n|
87 lon << n["lon"].to_f * GeoRecord::SCALE
88 lat << n["lat"].to_f * GeoRecord::SCALE
91 # add the existing bounding box to the lon-lat array
92 lon << cs.min_lon unless cs.min_lon.nil?
93 lat << cs.min_lat unless cs.min_lat.nil?
94 lon << cs.max_lon unless cs.max_lon.nil?
95 lat << cs.max_lat unless cs.max_lat.nil?
97 # collapse the arrays to minimum and maximum
103 # save the larger bounding box and return the changeset, which
104 # will include the bigger bounding box.
111 # Upload a diff in a single transaction.
113 # This means that each change within the diff must succeed, i.e: that
114 # each version number mentioned is still current. Otherwise the entire
115 # transaction *must* be rolled back.
117 # Furthermore, each element in the diff can only reference the current
120 # Returns: a diffResult document, as described in
121 # http://wiki.openstreetmap.org/wiki/OSM_Protocol_Version_0.6
123 # only allow POST requests, as the upload method is most definitely
124 # not idempotent, as several uploads with placeholder IDs will have
125 # different side-effects.
126 # see http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html#sec9.1.2
129 changeset = Changeset.find(params[:id])
130 check_changeset_consistency(changeset, current_user)
132 diff_reader = DiffReader.new(request.raw_post, changeset)
133 Changeset.transaction do
134 result = diff_reader.commit
135 render :xml => result.to_s
140 # download the changeset as an osmChange document.
142 # to make it easier to revert diffs it would be better if the osmChange
143 # format were reversible, i.e: contained both old and new versions of
144 # modified elements. but it doesn't at the moment...
146 # this method cannot order the database changes fully (i.e: timestamp and
147 # version number may be too coarse) so the resulting diff may not apply
148 # to a different database. however since changesets are not atomic this
149 # behaviour cannot be guaranteed anyway and is the result of a design
152 changeset = Changeset.find(params[:id])
154 # get all the elements in the changeset which haven't been redacted
155 # and stick them in a big array.
156 elements = [changeset.old_nodes.unredacted,
157 changeset.old_ways.unredacted,
158 changeset.old_relations.unredacted].flatten
160 # sort the elements by timestamp and version number, as this is the
161 # almost sensible ordering available. this would be much nicer if
162 # global (SVN-style) versioning were used - then that would be
164 elements.sort! do |a, b|
165 if a.timestamp == b.timestamp
166 a.version <=> b.version
168 a.timestamp <=> b.timestamp
172 # create changeset and user caches
174 user_display_name_cache = {}
176 # create an osmChange document for the output
177 result = OSM::API.new.get_xml_doc
178 result.root.name = "osmChange"
180 # generate an output element for each operation. note: we avoid looking
181 # at the history because it is simpler - but it would be more correct to
182 # check these assertions.
183 elements.each do |elt|
186 # first version, so it must be newly-created.
187 created = XML::Node.new "create"
188 created << elt.to_xml_node(changeset_cache, user_display_name_cache)
191 modified = XML::Node.new "modify"
192 modified << elt.to_xml_node(changeset_cache, user_display_name_cache)
194 # if the element isn't visible then it must have been deleted
195 deleted = XML::Node.new "delete"
196 deleted << elt.to_xml_node(changeset_cache, user_display_name_cache)
200 render :xml => result.to_s
204 # query changesets by bounding box, time, user or open/closed status.
206 # find any bounding box
207 bbox = BoundingBox.from_bbox_params(params) if params["bbox"]
209 # create the conditions that the user asked for. some or all of
211 changesets = Changeset.all
212 changesets = conditions_bbox(changesets, bbox)
213 changesets = conditions_user(changesets, params["user"], params["display_name"])
214 changesets = conditions_time(changesets, params["time"])
215 changesets = conditions_open(changesets, params["open"])
216 changesets = conditions_closed(changesets, params["closed"])
217 changesets = conditions_ids(changesets, params["changesets"])
219 # sort and limit the changesets
220 changesets = changesets.order("created_at DESC").limit(100)
222 # preload users, tags and comments, and render result
223 @changesets = changesets.preload(:user, :changeset_tags, :comments)
228 # updates a changeset's tags. none of the changeset's attributes are
229 # user-modifiable, so they will be ignored.
231 # changesets are not (yet?) versioned, so we don't have to deal with
232 # history tables here. changesets are locked to a single user, however.
234 # after succesful update, returns the XML of the changeset.
236 # request *must* be a PUT.
239 @changeset = Changeset.find(params[:id])
240 new_changeset = Changeset.from_xml(request.raw_post)
242 check_changeset_consistency(@changeset, current_user)
243 @changeset.update_from(new_changeset, current_user)
248 # Adds a subscriber to the changeset
250 # Check the arguments are sane
251 raise OSM::APIBadUserInput, "No id was given" unless params[:id]
253 # Extract the arguments
254 id = params[:id].to_i
256 # Find the changeset and check it is valid
257 changeset = Changeset.find(id)
258 raise OSM::APIChangesetAlreadySubscribedError, changeset if changeset.subscribers.exists?(current_user.id)
261 changeset.subscribers << current_user
263 # Return a copy of the updated changeset
264 @changeset = changeset
269 # Removes a subscriber from the changeset
271 # Check the arguments are sane
272 raise OSM::APIBadUserInput, "No id was given" unless params[:id]
274 # Extract the arguments
275 id = params[:id].to_i
277 # Find the changeset and check it is valid
278 changeset = Changeset.find(id)
279 raise OSM::APIChangesetNotSubscribedError, changeset unless changeset.subscribers.exists?(current_user.id)
281 # Remove the subscriber
282 changeset.subscribers.delete(current_user)
284 # Return a copy of the updated changeset
285 @changeset = changeset
291 #------------------------------------------------------------
292 # utility functions below.
293 #------------------------------------------------------------
296 # if a bounding box was specified do some sanity checks.
297 # restrict changesets to those enclosed by a bounding box
298 # we need to return both the changesets and the bounding box
299 def conditions_bbox(changesets, bbox)
301 bbox.check_boundaries
302 bbox = bbox.to_scaled
304 changesets.where("min_lon < ? and max_lon > ? and min_lat < ? and max_lat > ?",
305 bbox.max_lon.to_i, bbox.min_lon.to_i,
306 bbox.max_lat.to_i, bbox.min_lat.to_i)
313 # restrict changesets to those by a particular user
314 def conditions_user(changesets, user, name)
315 if user.nil? && name.nil?
318 # shouldn't provide both name and UID
319 raise OSM::APIBadUserInput, "provide either the user ID or display name, but not both" if user && name
321 # use either the name or the UID to find the user which we're selecting on.
323 # user input checking, we don't have any UIDs < 1
324 raise OSM::APIBadUserInput, "invalid user ID" if user.to_i < 1
326 u = User.find(user.to_i)
328 u = User.find_by(:display_name => name)
331 # make sure we found a user
332 raise OSM::APINotFoundError if u.nil?
334 # should be able to get changesets of public users only, or
335 # our own changesets regardless of public-ness.
336 unless u.data_public?
337 # get optional user auth stuff so that users can see their own
338 # changesets if they're non-public
341 raise OSM::APINotFoundError if current_user.nil? || current_user != u
344 changesets.where(:user_id => u.id)
349 # restrict changes to those closed during a particular time period
350 def conditions_time(changesets, time)
353 elsif time.count(",") == 1
354 # if there is a range, i.e: comma separated, then the first is
355 # low, second is high - same as with bounding boxes.
357 # check that we actually have 2 elements in the array
358 times = time.split(/,/)
359 raise OSM::APIBadUserInput, "bad time range" if times.size != 2
361 from, to = times.collect { |t| Time.parse(t) }
362 changesets.where("closed_at >= ? and created_at <= ?", from, to)
364 # if there is no comma, assume its a lower limit on time
365 changesets.where("closed_at >= ?", Time.parse(time))
367 # stupid Time seems to throw both of these for bad parsing, so
368 # we have to catch both and ensure the correct code path is taken.
369 rescue ArgumentError => ex
370 raise OSM::APIBadUserInput, ex.message.to_s
371 rescue RuntimeError => ex
372 raise OSM::APIBadUserInput, ex.message.to_s
376 # return changesets which are open (haven't been closed yet)
377 # we do this by seeing if the 'closed at' time is in the future. Also if we've
378 # hit the maximum number of changes then it counts as no longer open.
379 # if parameter 'open' is nill then open and closed changesets are returned
380 def conditions_open(changesets, open)
384 changesets.where("closed_at >= ? and num_changes <= ?",
385 Time.now.getutc, Changeset::MAX_ELEMENTS)
390 # query changesets which are closed
391 # ('closed at' time has passed or changes limit is hit)
392 def conditions_closed(changesets, closed)
396 changesets.where("closed_at < ? or num_changes > ?",
397 Time.now.getutc, Changeset::MAX_ELEMENTS)
402 # query changesets by a list of ids
403 # (either specified as array or comma-separated string)
404 def conditions_ids(changesets, ids)
408 raise OSM::APIBadUserInput, "No changesets were given to search for"
410 ids = ids.split(",").collect(&:to_i)
411 changesets.where(:id => ids)