OsmApi.py

   1 #-*- coding: utf-8 -*-
   2
   3 ###########################################################################
   4 ##                                                                       ##
   5 ## Copyrights Etienne Chové <chove@crans.org> 2009                       ##
   6 ##                                                                       ##
   7 ## This program is free software: you can redistribute it and/or modify  ##
   8 ## it under the terms of the GNU General Public License as published by  ##
   9 ## the Free Software Foundation, either version 3 of the License, or     ##
  10 ## (at your option) any later version.                                   ##
  11 ##                                                                       ##
  12 ## This program is distributed in the hope that it will be useful,       ##
  13 ## but WITHOUT ANY WARRANTY; without even the implied warranty of        ##
  14 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         ##
  15 ## GNU General Public License for more details.                          ##
  16 ##                                                                       ##
  17 ## You should have received a copy of the GNU General Public License     ##
  18 ## along with this program.  If not, see <http://www.gnu.org/licenses/>. ##
  19 ##                                                                       ##
  20 ###########################################################################
  21
  22 ## HomePage : http://wiki.openstreetmap.org/wiki/PythonOsmApi
  23
  24 ###########################################################################
  25 ## History                                                               ##
  26 ###########################################################################
  27 ## 0.2.8   2009-10-13 *(Create|Update|Delete) use not unique _do method  ##
  28 ## 0.2.7   2009-10-09 implement all missing fonctions except             ##
  29 ##                    ChangesetsGet and GetCapabilities                  ##
  30 ## 0.2.6   2009-10-09 encoding clean-up                                  ##
  31 ## 0.2.5   2009-10-09 implements NodesGet, WaysGet, RelationsGet         ##
  32 ##                               ParseOsm, ParseOsc                      ##
  33 ## 0.2.4   2009-10-06 clean-up                                           ##
  34 ## 0.2.3   2009-09-09 keep http connection alive for multiple request    ##
  35 ##                    (Node|Way|Relation)Get return None when object     ##
  36 ##                    have been deleted (raising error before)           ##
  37 ## 0.2.2   2009-07-13 can identify applications built on top of the lib  ##
  38 ## 0.2.1   2009-05-05 some changes in constructor -- chove@crans.org     ##
  39 ## 0.2     2009-05-01 initial import                                     ##
  40 ###########################################################################
  41
  42 __version__ = '0.2.8'
  43
  44 import httplib, base64, xml.dom.minidom, time
  45
  46 ###########################################################################
  47 ## Main class                                                            ##
  48
  49 class OsmApi:
  50
  51     def __init__(self,
  52         username = None,
  53         password = None,
  54         passwordfile = None,
  55         appid = "",
  56         created_by = "PythonOsmApi/"+__version__,
  57         api = "www.openstreetmap.org",
  58         changesetauto = False,
  59         changesetautotags = {},
  60         changesetautosize = 500,
  61         changesetautogroup = False):
  62
  63         # Get username
  64         if username:
  65             self._username = username
  66         elif passwordfile:
  67             self._username =  open(passwordfile).readline().split(":")[0].strip()
  68
  69         # Get password
  70         if password:
  71             self._password   = password
  72         elif passwordfile:
  73             for l in open(passwordfile).readlines():
  74                 l = l.strip().split(":")
  75                 if l[0] == self._username:
  76                     self._password = l[1]
  77
  78         # Changest informations
  79         self._changesetauto      = changesetauto      # auto create and close changesets
  80         self._changesetautotags  = changesetautotags  # tags for automatic created changesets
  81         self._changesetautosize  = changesetautosize  # change count for auto changeset
  82         self._changesetautogroup = changesetautogroup # group data to upload (NodeCreate, NodeUpdate... will return None)
  83         self._changesetautodata  = []                 # data to upload for auto group
  84
  85         # Get API
  86         self._api = api
  87
  88         # Get created_by
  89         if not appid:
  90             self._created_by = created_by
  91         else:
  92             self._created_by = appid + " (" + created_by + ")"
  93
  94         # Initialisation
  95         self._CurrentChangesetId = 0
  96
  97         # Http connection
  98         self._conn = httplib.HTTPConnection(self._api, 80)
  99
 100     #######################################################################
 101     # Capabilities                                                        #
 102     #######################################################################
 103
 104     def Capabilities(self):
 105         raise NotImplemented
 106
 107     #######################################################################
 108     # Node                                                                #
 109     #######################################################################
 110
 111     def NodeGet(self, NodeId, NodeVersion = -1):
 112         """ Returns NodeData for node #NodeId. """
 113         uri = "/api/0.6/node/"+str(NodeId)
 114         if NodeVersion <> -1: uri += "/"+str(NodeVersion)
 115         data = self._get(uri)
 116         if not data: return data
 117         data = xml.dom.minidom.parseString(data)
 118         data = data.getElementsByTagName("osm")[0].getElementsByTagName("node")[0]
 119         return self._DomParseNode(data)
 120
 121     def NodeCreate(self, NodeData):
 122         """ Creates a node. Returns updated NodeData (without timestamp). """
 123         return self._do("create", "node", NodeData)
 124
 125     def NodeUpdate(self, NodeData):
 126         """ Updates node with NodeData. Returns updated NodeData (without timestamp). """
 127         return self._do("update", "node", NodeData)
 128
 129     def NodeDelete(self, NodeData):
 130         """ Delete node with NodeData. Returns updated NodeData (without timestamp). """
 131         return self._do("delete", "node", NodeData)
 132
 133     def NodeHistory(self, NodeId):
 134         """ Returns dict(NodeVerrsion: NodeData). """
 135         uri = "/api/0.6/node/"+str(NodeId)+"/history"
 136         data = self._get(uri)
 137         data = xml.dom.minidom.parseString(data)
 138         result = {}
 139         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("node"):
 140             data = self._DomParseNode(data)
 141             result[data[u"version"]] = data
 142         return result
 143
 144     def NodeWays(self, NodeId):
 145         """ Returns [WayData, ... ] containing node #NodeId. """
 146         uri = "/api/0.6/node/%d/ways"%NodeId
 147         data = self._get(uri)
 148         data = xml.dom.minidom.parseString(data)
 149         result = []
 150         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("way"):
 151             data = self._DomParseRelation(data)
 152             result.append(data)
 153         return result
 154
 155     def NodeRelations(self, NodeId):
 156         """ Returns [RelationData, ... ] containing node #NodeId. """
 157         uri = "/api/0.6/node/%d/relations"%NodeId
 158         data = self._get(uri)
 159         data = xml.dom.minidom.parseString(data)
 160         result = []
 161         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("relation"):
 162             data = self._DomParseRelation(data)
 163             result.append(data)
 164         return result
 165
 166     def NodesGet(self, NodeIdList):
 167         """ Returns dict(NodeId: NodeData) for each node in NodeIdList """
 168         uri  = "/api/0.6/nodes?nodes=" + ",".join([str(x) for x in NodeIdList])
 169         data = self._get(uri)
 170         data = xml.dom.minidom.parseString(data)
 171         result = {}
 172         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("node"):
 173             data = self._DomParseNode(data)
 174             result[data[u"id"]] = data
 175         return result
 176
 177     #######################################################################
 178     # Way                                                                 #
 179     #######################################################################
 180
 181     def WayGet(self, WayId, WayVersion = -1):
 182         """ Returns WayData for way #WayId. """
 183         uri = "/api/0.6/way/"+str(WayId)
 184         if WayVersion <> -1: uri += "/"+str(WayVersion)
 185         data = self._get(uri)
 186         if not data: return data
 187         data = xml.dom.minidom.parseString(data)
 188         data = data.getElementsByTagName("osm")[0].getElementsByTagName("way")[0]
 189         return self._DomParseWay(data)
 190
 191     def WayCreate(self, WayData):
 192         """ Creates a way. Returns updated WayData (without timestamp). """
 193         return self._do("create", "way", WayData)
 194
 195     def WayUpdate(self, WayData):
 196         """ Updates way with WayData. Returns updated WayData (without timestamp). """
 197         return self._do("update", "way", WayData)
 198
 199     def WayDelete(self, WayData):
 200         """ Delete way with WayData. Returns updated WayData (without timestamp). """
 201         return self._do("delete", "way", WayData)
 202
 203     def WayHistory(self, WayId):
 204         """ Returns dict(WayVerrsion: WayData). """
 205         uri = "/api/0.6/way/"+str(WayId)+"/history"
 206         data = self._get(uri)
 207         data = xml.dom.minidom.parseString(data)
 208         result = {}
 209         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("way"):
 210             data = self._DomParseWay(data)
 211             result[data[u"version"]] = data
 212         return result
 213
 214     def WayRelations(self, WayId):
 215         """ Returns [RelationData, ...] containing way #WayId. """
 216         uri = "/api/0.6/way/%d/relations"%WayId
 217         data = self._get(uri)
 218         data = xml.dom.minidom.parseString(data)
 219         result = []
 220         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("relation"):
 221             data = self._DomParseRelation(data)
 222             result.append(data)
 223         return result
 224
 225     def WayFull(self, WayId):
 226         """ Return full data for way WayId as list of {type: node|way|relation, data: {}}. """
 227         uri = "/api/0.6/way/"+str(WayId)+"/full"
 228         data = self._get(uri)
 229         return self.ParseOsm(data)
 230
 231     def WaysGet(self, WayIdList):
 232         """ Returns dict(WayId: WayData) for each way in WayIdList """
 233         uri = "/api/0.6/ways?ways=" + ",".join([str(x) for x in WayIdList])
 234         data = self._get(uri)
 235         data = xml.dom.minidom.parseString(data)
 236         result = {}
 237         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("way"):
 238             data = self._DomParseWay(data)
 239             result[data[u"id"]] = data
 240         return result
 241
 242     #######################################################################
 243     # Relation                                                            #
 244     #######################################################################
 245
 246     def RelationGet(self, RelationId, RelationVersion = -1):
 247         """ Returns RelationData for relation #RelationId. """
 248         uri = "/api/0.6/relation/"+str(RelationId)
 249         if RelationVersion <> -1: uri += "/"+str(RelationVersion)
 250         data = self._get(uri)
 251         if not data: return data
 252         data = xml.dom.minidom.parseString(data)
 253         data = data.getElementsByTagName("osm")[0].getElementsByTagName("relation")[0]
 254         return self._DomParseRelation(data)
 255
 256     def RelationCreate(self, RelationData):
 257         """ Creates a relation. Returns updated RelationData (without timestamp). """
 258         return self._do("create", "relation", RelationData)
 259
 260     def RelationUpdate(self, RelationData):
 261         """ Updates relation with RelationData. Returns updated RelationData (without timestamp). """
 262         return self._do("update", "relation", RelationData)
 263
 264     def RelationDelete(self, RelationData):
 265         """ Delete relation with RelationData. Returns updated RelationData (without timestamp). """
 266         return self._do("delete", "relation", RelationData)
 267
 268     def RelationHistory(self, RelationId):
 269         """ Returns dict(RelationVerrsion: RelationData). """
 270         uri = "/api/0.6/relation/"+str(RelationId)+"/history"
 271         data = self._get(uri)
 272         data = xml.dom.minidom.parseString(data)
 273         result = {}
 274         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("relation"):
 275             data = self._DomParseRelation(data)
 276             result[data[u"version"]] = data
 277         return result
 278
 279     def RelationRelations(self, RelationId):
 280         """ Returns list of RelationData containing relation #RelationId. """
 281         uri = "/api/0.6/relation/%d/relations"%RelationId
 282         data = self._get(uri)
 283         data = xml.dom.minidom.parseString(data)
 284         result = []
 285         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("relation"):
 286             data = self._DomParseRelation(data)
 287             result.append(data)
 288         return result
 289
 290     def RelationFull(self, RelationId):
 291         """ Return full data for way WayId as list of {type: node|way|relation, data: {}}. """
 292         uri = "/api/0.6/relation/"+str(RelationId)+"/full"
 293         data = self._get(uri)
 294         return self.ParseOsm(data)
 295
 296     def RelationsGet(self, RelationIdList):
 297         """ Returns dict(RelationId: RelationData) for each relation in RelationIdList """
 298         uri = "/api/0.6/relations?relations=" + ",".join([str(x) for x in RelationIdList])
 299         data = self._get(uri)
 300         data = xml.dom.minidom.parseString(data)
 301         result = {}
 302         for data in data.getElementsByTagName("osm")[0].getElementsByTagName("relation"):
 303             data = self._DomParseRelation(data)
 304             result[data[u"id"]] = data
 305         return result
 306
 307     #######################################################################
 308     # Changeset                                                           #
 309     #######################################################################
 310
 311     def ChangesetGet(self, ChangesetId):
 312         """ Returns ChangesetData for changeset #ChangesetId. """
 313         data = self._get("/api/0.6/changeset/"+str(ChangesetId))
 314         data = xml.dom.minidom.parseString(data)
 315         data = data.getElementsByTagName("osm")[0].getElementsByTagName("changeset")[0]
 316         return self._DomParseChangeset(data)
 317
 318     def ChangesetUpdate(self, ChangesetTags = {}):
 319         """ Updates current changeset with ChangesetTags. """
 320         if self._CurrentChangesetId == -1:
 321             raise Exception, "No changeset currently opened"
 322         if u"created_by" not in ChangesetTags:
 323             ChangesetTags[u"created_by"] = self._created_by
 324         result = self._put("/api/0.6/changeset/"+str(self._CurrentChangesetId), self._XmlBuild("changeset", {u"tag": ChangesetTags}))
 325         return self._CurrentChangesetId
 326
 327     def ChangesetCreate(self, ChangesetTags = {}):
 328         """ Opens a changeset. Returns #ChangesetId. """
 329         if self._CurrentChangesetId:
 330             raise Exception, "Changeset alreadey opened"
 331         if u"created_by" not in ChangesetTags:
 332             ChangesetTags[u"created_by"] = self._created_by
 333         result = self._put("/api/0.6/changeset/create", self._XmlBuild("changeset", {u"tag": ChangesetTags}))
 334         self._CurrentChangesetId = int(result)
 335         return self._CurrentChangesetId
 336
 337     def ChangesetClose(self):
 338         """ Closes current changeset. Returns #ChangesetId. """
 339         if not self._CurrentChangesetId:
 340             raise Exception, "No changeset currently opened"
 341         result = self._put("/api/0.6/changeset/"+str(self._CurrentChangesetId)+"/close", u"")
 342         CurrentChangesetId = self._CurrentChangesetId
 343         self._CurrentChangesetId = 0
 344         return CurrentChangesetId
 345
 346     def ChangesetUpload(self):
 347         raise NotImplemented
 348
 349     def ChangesetDownload(self, ChangesetId):
 350         """ Download data from a changeset. Returns list of dict {type: node|way|relation, action: create|delete|modify, data: {}}. """
 351         uri = "/api/0.6/changeset/"+str(ChangesetId)+"/download"
 352         data = self._get(uri)
 353         return self.ParseOsc(data)
 354
 355     def ChangesetsGet(self, min_lon=None, min_lat=None, max_lon=None, max_lat=None, userid=None, closed_after=None, created_before=None, only_open=False, only_closed=False):
 356         """ Returns dict(ChangsetId: ChangesetData) matching all criteria. """
 357         raise NotImplemented
 358
 359     #######################################################################
 360     # Other                                                               #
 361     #######################################################################
 362
 363     def Map(self, min_lon, min_lat, max_lon, max_lat):
 364         """ Download data in bounding box. Returns list of dict {type: node|way|relation, data: {}}. """
 365         uri = "/api/0.6/map?bbox=%f,%f,%f,%f"%(min_lon, min_lat, max_lon, max_lat)
 366         data = self._get(uri)
 367         return self.ParseOsm(data)
 368
 369     #######################################################################
 370     # Data parser                                                         #
 371     #######################################################################
 372
 373     def ParseOsm(self, data):
 374         """ Parse osm data. Returns list of dict {type: node|way|relation, data: {}}. """
 375         data = xml.dom.minidom.parseString(data)
 376         data = data.getElementsByTagName("osm")[0]
 377         result = []
 378         for elem in data.childNodes:
 379             if elem.nodeName == u"node":
 380                 result.append({u"type": elem.nodeName, u"data": self._DomParseNode(elem)})
 381             elif elem.nodeName == u"way":
 382                 result.append({u"type": elem.nodeName, u"data": self._DomParseWay(elem)})
 383             elif elem.nodeName == u"relation":
 384                 result.append({u"type": elem.nodeName, u"data": self._DomParseRelation(elem)})
 385         return result
 386
 387     def ParseOsc(self, data):
 388         """ Parse osc data. Returns list of dict {type: node|way|relation, action: create|delete|modify, data: {}}. """
 389         data = xml.dom.minidom.parseString(data)
 390         data = data.getElementsByTagName("osmChange")[0]
 391         result = []
 392         for action in data.childNodes:
 393             if action.nodeName == u"#text": continue
 394             for elem in action.childNodes:
 395                 if elem.nodeName == u"node":
 396                     result.append({u"action":action.nodeName, u"type": elem.nodeName, u"data": self._DomParseNode(elem)})
 397                 elif elem.nodeName == u"way":
 398                     result.append({u"action":action.nodeName, u"type": elem.nodeName, u"data": self._DomParseWay(elem)})
 399                 elif elem.nodeName == u"relation":
 400                     result.append({u"action":action.nodeName, u"type": elem.nodeName, u"data": self._DomParseRelation(elem)})
 401         return result
 402
 403     #######################################################################
 404     # Internal http function                                              #
 405     #######################################################################
 406
 407     def _do(self, action, OsmType, OsmData):
 408
 409         if u"timestamp" in OsmData:
 410             OsmData.pop(u"timestamp")
 411
 412         if not self._CurrentChangesetId:
 413             raise Exception, "You need to open a changeset before uploading data"
 414         OsmData[u"changeset"] = self._CurrentChangesetId
 415         if action == "create":
 416             if OsmData.get(u"id", -1) > 0:
 417                 raise Exception, "This "+OsmType+" already exists"
 418             result = self._put("/api/0.6/"+OsmType+"/create", self._XmlBuild(OsmType, OsmData))
 419             OsmData[u"id"] = int(result.strip())
 420             OsmData[u"version"] = 1
 421             return OsmData
 422         elif action == "update":
 423             result = self._put("/api/0.6/"+OsmType+"/"+str(OsmData[u"id"]), self._XmlBuild(OsmType, OsmData))
 424             OsmData[u"version"] = int(result.strip())
 425             return OsmData
 426         elif action =="delete":
 427             result = self._delete("/api/0.6/"+OsmType+"/"+str(OsmData[u"id"]), self._XmlBuild(OsmType, OsmData))
 428             OsmData[u"version"] = int(result.strip())
 429             OsmData[u"visible"] = False
 430             return OsmData
 431
 432     def _http_request(self, cmd, path, auth, send):
 433         self._conn.putrequest(cmd, path)
 434         self._conn.putheader('User-Agent', self._created_by)
 435         if auth:
 436             self._conn.putheader('Authorization', 'Basic ' + base64.encodestring(self._username + ':' + self._password).strip())
 437         if send:
 438             self._conn.putheader('Content-Length', len(send))
 439         self._conn.endheaders()
 440         if send:
 441             self._conn.send(send)
 442         response = self._conn.getresponse()
 443         if response.status <> 200:
 444             response.read()
 445             if response.status == 410:
 446                 return None
 447             raise Exception, "API returns unexpected status code "+str(response.status)+" ("+response.reason+")"
 448         return response.read()
 449
 450     def _http(self, cmd, path, auth, send):
 451         i = 0
 452         while True:
 453             i += 1
 454             try:
 455                 return self._http_request(cmd, path, auth, send)
 456             except:
 457                 if i == 5: raise
 458                 if i <> 1: time.sleep(2)
 459                 self._conn = httplib.HTTPConnection(self._api, 80)
 460
 461     def _get(self, path):
 462         return self._http('GET', path, False, None)
 463
 464     def _put(self, path, data):
 465         return self._http('PUT', path, True, data)
 466
 467     def _delete(self, path, data):
 468         return self._http('DELETE', path, True, data)
 469
 470     #######################################################################
 471     # Internal dom function                                               #
 472     #######################################################################
 473
 474     def _DomGetAttributes(self, DomElement):
 475         """ Returns a formated dictionnary of attributes of a DomElement. """
 476         result = {}
 477         for k, v in DomElement.attributes.items():
 478             if k == u"uid"         : v = int(v)
 479             elif k == u"changeset" : v = int(v)
 480             elif k == u"version"   : v = int(v)
 481             elif k == u"id"        : v = int(v)
 482             elif k == u"lat"       : v = float(v)
 483             elif k == u"lon"       : v = float(v)
 484             elif k == u"open"      : v = v=="true"
 485             elif k == u"visible"   : v = v=="true"
 486             elif k == u"ref"       : v = int(v)
 487             result[k] = v
 488         return result
 489
 490     def _DomGetTag(self, DomElement):
 491         """ Returns the dictionnary of tags of a DomElement. """
 492         result = {}
 493         for t in DomElement.getElementsByTagName("tag"):
 494             k = t.attributes["k"].value
 495             v = t.attributes["v"].value
 496             result[k] = v
 497         return result
 498
 499     def _DomGetNd(self, DomElement):
 500         """ Returns the list of nodes of a DomElement. """
 501         result = []
 502         for t in DomElement.getElementsByTagName("nd"):
 503             result.append(int(int(t.attributes["ref"].value)))
 504         return result
 505
 506     def _DomGetMember(self, DomElement):
 507         """ Returns a list of relation members. """
 508         result = []
 509         for m in DomElement.getElementsByTagName("member"):
 510             result.append(self._DomGetAttributes(m))
 511         return result
 512
 513     def _DomParseNode(self, DomElement):
 514         """ Returns NodeData for the node. """
 515         result = self._DomGetAttributes(DomElement)
 516         result[u"tag"] = self._DomGetTag(DomElement)
 517         return result
 518
 519     def _DomParseWay(self, DomElement):
 520         """ Returns WayData for the way. """
 521         result = self._DomGetAttributes(DomElement)
 522         result[u"tag"] = self._DomGetTag(DomElement)
 523         result[u"nd"]  = self._DomGetNd(DomElement)
 524         return result
 525
 526     def _DomParseRelation(self, DomElement):
 527         """ Returns RelationData for the relation. """
 528         result = self._DomGetAttributes(DomElement)
 529         result[u"tag"]    = self._DomGetTag(DomElement)
 530         result[u"member"] = self._DomGetMember(DomElement)
 531         return result
 532
 533     def _DomParseChangeset(self, DomElement):
 534         """ Returns ChangesetData for the changeset. """
 535         result = self._DomGetAttributes(DomElement)
 536         result[u"tag"] = self._DomGetTag(DomElement)
 537         return result
 538
 539     #######################################################################
 540     # Internal xml builder                                                #
 541     #######################################################################
 542
 543     def _XmlBuild(self, ElementType, ElementData):
 544
 545         xml  = u""
 546         xml += u"<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n"
 547         xml += u"<osm version=\"0.6\" generator=\"" + self._created_by + "\">\n"
 548
 549         # <element attr="val">
 550         xml += u"  <" + ElementType
 551         if u"id" in ElementData:
 552             xml += u" id=\"" + str(ElementData[u"id"]) + u"\""
 553         if u"lat" in ElementData:
 554             xml += u" lat=\"" + str(ElementData[u"lat"]) + u"\""
 555         if u"lon" in ElementData:
 556             xml += u" lon=\"" + str(ElementData[u"lon"]) + u"\""
 557         if u"version" in ElementData:
 558             xml += u" version=\"" + str(ElementData[u"version"]) + u"\""
 559         xml += u" visible=\"" + str(ElementData.get(u"visible", True)).lower() + u"\""
 560         if ElementType in [u"node", u"way", u"relation"]:
 561             xml += u" changeset=\"" + str(self._CurrentChangesetId) + u"\""
 562         xml += u">\n"
 563
 564         # <tag... />
 565         for k, v in ElementData.get(u"tag", {}).items():
 566             xml += u"    <tag k=\""+self._XmlEncode(k)+u"\" v=\""+self._XmlEncode(v)+u"\"/>\n"
 567
 568         # <member... />
 569         for member in ElementData.get(u"member", []):
 570             xml += u"    <member type=\""+member[u"type"]+"\" ref=\""+str(member[u"ref"])+u"\" role=\""+self._XmlEncode(member[u"role"])+"\"/>\n"
 571
 572         # <nd... />
 573         for ref in ElementData.get(u"nd", []):
 574             xml += u"    <nd ref=\""+str(ref)+u"\"/>\n"
 575
 576         # </element>
 577         xml += u"  </" + ElementType + u">\n"
 578
 579         xml += u"</osm>\n"
 580
 581         return xml.encode("utf8")
 582
 583     def _XmlEncode(self, text):
 584         return text.replace("&", "&amp;").replace("\"", "&quot;")
 585
 586 ## End of main class                                                     ##
 587 ###########################################################################