paul@213 | 1 | #!/usr/bin/env python |
paul@213 | 2 | |
paul@213 | 3 | """ |
paul@213 | 4 | Interpretation of vCalendar content. |
paul@213 | 5 | |
paul@213 | 6 | Copyright (C) 2014, 2015 Paul Boddie <paul@boddie.org.uk> |
paul@213 | 7 | |
paul@213 | 8 | This program is free software; you can redistribute it and/or modify it under |
paul@213 | 9 | the terms of the GNU General Public License as published by the Free Software |
paul@213 | 10 | Foundation; either version 3 of the License, or (at your option) any later |
paul@213 | 11 | version. |
paul@213 | 12 | |
paul@213 | 13 | This program is distributed in the hope that it will be useful, but WITHOUT |
paul@213 | 14 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
paul@213 | 15 | FOR A PARTICULAR PURPOSE. See the GNU General Public License for more |
paul@213 | 16 | details. |
paul@213 | 17 | |
paul@213 | 18 | You should have received a copy of the GNU General Public License along with |
paul@213 | 19 | this program. If not, see <http://www.gnu.org/licenses/>. |
paul@213 | 20 | """ |
paul@213 | 21 | |
paul@256 | 22 | from datetime import datetime, timedelta |
paul@213 | 23 | from email.mime.text import MIMEText |
paul@291 | 24 | from imiptools.dates import format_datetime, get_datetime, get_freebusy_period, \ |
paul@318 | 25 | to_timezone, to_utc_datetime |
paul@327 | 26 | from imiptools.period import period_overlaps |
paul@316 | 27 | from pytz import timezone |
paul@213 | 28 | from vCalendar import iterwrite, parse, ParseError, to_dict, to_node |
paul@256 | 29 | from vRecurrence import get_parameters, get_rule |
paul@213 | 30 | import email.utils |
paul@213 | 31 | |
paul@213 | 32 | try: |
paul@213 | 33 | from cStringIO import StringIO |
paul@213 | 34 | except ImportError: |
paul@213 | 35 | from StringIO import StringIO |
paul@213 | 36 | |
paul@213 | 37 | class Object: |
paul@213 | 38 | |
paul@213 | 39 | "Access to calendar structures." |
paul@213 | 40 | |
paul@213 | 41 | def __init__(self, fragment): |
paul@213 | 42 | self.objtype, (self.details, self.attr) = fragment.items()[0] |
paul@213 | 43 | |
paul@213 | 44 | def get_items(self, name, all=True): |
paul@213 | 45 | return get_items(self.details, name, all) |
paul@213 | 46 | |
paul@213 | 47 | def get_item(self, name): |
paul@213 | 48 | return get_item(self.details, name) |
paul@213 | 49 | |
paul@213 | 50 | def get_value_map(self, name): |
paul@213 | 51 | return get_value_map(self.details, name) |
paul@213 | 52 | |
paul@213 | 53 | def get_values(self, name, all=True): |
paul@213 | 54 | return get_values(self.details, name, all) |
paul@213 | 55 | |
paul@213 | 56 | def get_value(self, name): |
paul@213 | 57 | return get_value(self.details, name) |
paul@213 | 58 | |
paul@213 | 59 | def get_utc_datetime(self, name): |
paul@213 | 60 | return get_utc_datetime(self.details, name) |
paul@213 | 61 | |
paul@352 | 62 | def get_item_datetimes(self, name): |
paul@352 | 63 | items = get_item_datetime_items(self.details, name) |
paul@352 | 64 | return items and [dt for dt, attr in items] |
paul@352 | 65 | |
paul@352 | 66 | def get_item_datetime_items(self, name): |
paul@352 | 67 | return get_item_datetime_items(self.details, name) |
paul@352 | 68 | |
paul@318 | 69 | def get_datetime(self, name): |
paul@318 | 70 | dt, attr = get_datetime_item(self.details, name) |
paul@318 | 71 | return dt |
paul@318 | 72 | |
paul@289 | 73 | def get_datetime_item(self, name): |
paul@289 | 74 | return get_datetime_item(self.details, name) |
paul@289 | 75 | |
paul@213 | 76 | def to_node(self): |
paul@213 | 77 | return to_node({self.objtype : [(self.details, self.attr)]}) |
paul@213 | 78 | |
paul@213 | 79 | def to_part(self, method): |
paul@213 | 80 | return to_part(method, [self.to_node()]) |
paul@213 | 81 | |
paul@213 | 82 | # Direct access to the structure. |
paul@213 | 83 | |
paul@213 | 84 | def __getitem__(self, name): |
paul@213 | 85 | return self.details[name] |
paul@213 | 86 | |
paul@213 | 87 | def __setitem__(self, name, value): |
paul@213 | 88 | self.details[name] = value |
paul@213 | 89 | |
paul@213 | 90 | def __delitem__(self, name): |
paul@213 | 91 | del self.details[name] |
paul@213 | 92 | |
paul@256 | 93 | # Computed results. |
paul@256 | 94 | |
paul@360 | 95 | def has_recurrence(self, tzid, recurrence): |
paul@360 | 96 | recurrences = [start for start, end in get_periods(self, tzid, recurrence, True)] |
paul@360 | 97 | return recurrence in recurrences |
paul@256 | 98 | |
paul@360 | 99 | def get_periods(self, tzid, end): |
paul@360 | 100 | return get_periods(self, tzid, end) |
paul@360 | 101 | |
paul@360 | 102 | def get_periods_for_freebusy(self, tzid, end): |
paul@360 | 103 | periods = self.get_periods(tzid, end) |
paul@291 | 104 | return get_periods_for_freebusy(self, periods, tzid) |
paul@291 | 105 | |
paul@213 | 106 | # Construction and serialisation. |
paul@213 | 107 | |
paul@213 | 108 | def make_calendar(nodes, method=None): |
paul@213 | 109 | |
paul@213 | 110 | """ |
paul@213 | 111 | Return a complete calendar node wrapping the given 'nodes' and employing the |
paul@213 | 112 | given 'method', if indicated. |
paul@213 | 113 | """ |
paul@213 | 114 | |
paul@213 | 115 | return ("VCALENDAR", {}, |
paul@213 | 116 | (method and [("METHOD", {}, method)] or []) + |
paul@213 | 117 | [("VERSION", {}, "2.0")] + |
paul@213 | 118 | nodes |
paul@213 | 119 | ) |
paul@213 | 120 | |
paul@327 | 121 | def make_freebusy(freebusy, uid, organiser, organiser_attr=None, attendee=None, |
paul@327 | 122 | attendee_attr=None, dtstart=None, dtend=None): |
paul@222 | 123 | |
paul@222 | 124 | """ |
paul@222 | 125 | Return a calendar node defining the free/busy details described in the given |
paul@292 | 126 | 'freebusy' list, employing the given 'uid', for the given 'organiser' and |
paul@292 | 127 | optional 'organiser_attr', with the optional 'attendee' providing recipient |
paul@292 | 128 | details together with the optional 'attendee_attr'. |
paul@327 | 129 | |
paul@327 | 130 | The result will be constrained to the 'dtstart' and 'dtend' period if these |
paul@327 | 131 | parameters are given. |
paul@222 | 132 | """ |
paul@222 | 133 | |
paul@222 | 134 | record = [] |
paul@222 | 135 | rwrite = record.append |
paul@222 | 136 | |
paul@292 | 137 | rwrite(("ORGANIZER", organiser_attr or {}, organiser)) |
paul@222 | 138 | |
paul@222 | 139 | if attendee: |
paul@292 | 140 | rwrite(("ATTENDEE", attendee_attr or {}, attendee)) |
paul@222 | 141 | |
paul@222 | 142 | rwrite(("UID", {}, uid)) |
paul@222 | 143 | |
paul@222 | 144 | if freebusy: |
paul@327 | 145 | |
paul@327 | 146 | # Get a constrained view if start and end limits are specified. |
paul@327 | 147 | |
paul@327 | 148 | periods = dtstart and dtend and period_overlaps(freebusy, (dtstart, dtend), True) or freebusy |
paul@327 | 149 | |
paul@327 | 150 | # Write the limits of the resource. |
paul@327 | 151 | |
paul@327 | 152 | rwrite(("DTSTART", {"VALUE" : "DATE-TIME"}, periods[0][0])) |
paul@327 | 153 | rwrite(("DTEND", {"VALUE" : "DATE-TIME"}, periods[-1][1])) |
paul@327 | 154 | |
paul@344 | 155 | for start, end, uid, transp, recurrenceid in periods: |
paul@222 | 156 | if transp == "OPAQUE": |
paul@222 | 157 | rwrite(("FREEBUSY", {"FBTYPE" : "BUSY"}, "/".join([start, end]))) |
paul@222 | 158 | |
paul@222 | 159 | return ("VFREEBUSY", {}, record) |
paul@222 | 160 | |
paul@213 | 161 | def parse_object(f, encoding, objtype=None): |
paul@213 | 162 | |
paul@213 | 163 | """ |
paul@213 | 164 | Parse the iTIP content from 'f' having the given 'encoding'. If 'objtype' is |
paul@213 | 165 | given, only objects of that type will be returned. Otherwise, the root of |
paul@213 | 166 | the content will be returned as a dictionary with a single key indicating |
paul@213 | 167 | the object type. |
paul@213 | 168 | |
paul@213 | 169 | Return None if the content was not readable or suitable. |
paul@213 | 170 | """ |
paul@213 | 171 | |
paul@213 | 172 | try: |
paul@213 | 173 | try: |
paul@213 | 174 | doctype, attrs, elements = obj = parse(f, encoding=encoding) |
paul@213 | 175 | if objtype and doctype == objtype: |
paul@213 | 176 | return to_dict(obj)[objtype][0] |
paul@213 | 177 | elif not objtype: |
paul@213 | 178 | return to_dict(obj) |
paul@213 | 179 | finally: |
paul@213 | 180 | f.close() |
paul@213 | 181 | |
paul@213 | 182 | # NOTE: Handle parse errors properly. |
paul@213 | 183 | |
paul@213 | 184 | except (ParseError, ValueError): |
paul@213 | 185 | pass |
paul@213 | 186 | |
paul@213 | 187 | return None |
paul@213 | 188 | |
paul@213 | 189 | def to_part(method, calendar): |
paul@213 | 190 | |
paul@213 | 191 | """ |
paul@213 | 192 | Write using the given 'method', the 'calendar' details to a MIME |
paul@213 | 193 | text/calendar part. |
paul@213 | 194 | """ |
paul@213 | 195 | |
paul@213 | 196 | encoding = "utf-8" |
paul@213 | 197 | out = StringIO() |
paul@213 | 198 | try: |
paul@213 | 199 | to_stream(out, make_calendar(calendar, method), encoding) |
paul@213 | 200 | part = MIMEText(out.getvalue(), "calendar", encoding) |
paul@213 | 201 | part.set_param("method", method) |
paul@213 | 202 | return part |
paul@213 | 203 | |
paul@213 | 204 | finally: |
paul@213 | 205 | out.close() |
paul@213 | 206 | |
paul@213 | 207 | def to_stream(out, fragment, encoding="utf-8"): |
paul@213 | 208 | iterwrite(out, encoding=encoding).append(fragment) |
paul@213 | 209 | |
paul@213 | 210 | # Structure access functions. |
paul@213 | 211 | |
paul@213 | 212 | def get_items(d, name, all=True): |
paul@213 | 213 | |
paul@213 | 214 | """ |
paul@213 | 215 | Get all items from 'd' for the given 'name', returning single items if |
paul@213 | 216 | 'all' is specified and set to a false value and if only one value is |
paul@213 | 217 | present for the name. Return None if no items are found for the name or if |
paul@213 | 218 | many items are found but 'all' is set to a false value. |
paul@213 | 219 | """ |
paul@213 | 220 | |
paul@213 | 221 | if d.has_key(name): |
paul@213 | 222 | values = d[name] |
paul@213 | 223 | if all: |
paul@213 | 224 | return values |
paul@213 | 225 | elif len(values) == 1: |
paul@213 | 226 | return values[0] |
paul@213 | 227 | else: |
paul@213 | 228 | return None |
paul@213 | 229 | else: |
paul@213 | 230 | return None |
paul@213 | 231 | |
paul@213 | 232 | def get_item(d, name): |
paul@213 | 233 | return get_items(d, name, False) |
paul@213 | 234 | |
paul@213 | 235 | def get_value_map(d, name): |
paul@213 | 236 | |
paul@213 | 237 | """ |
paul@213 | 238 | Return a dictionary for all items in 'd' having the given 'name'. The |
paul@213 | 239 | dictionary will map values for the name to any attributes or qualifiers |
paul@213 | 240 | that may have been present. |
paul@213 | 241 | """ |
paul@213 | 242 | |
paul@213 | 243 | items = get_items(d, name) |
paul@213 | 244 | if items: |
paul@213 | 245 | return dict(items) |
paul@213 | 246 | else: |
paul@213 | 247 | return {} |
paul@213 | 248 | |
paul@213 | 249 | def get_values(d, name, all=True): |
paul@213 | 250 | if d.has_key(name): |
paul@213 | 251 | values = d[name] |
paul@213 | 252 | if not all and len(values) == 1: |
paul@213 | 253 | return values[0][0] |
paul@213 | 254 | else: |
paul@213 | 255 | return map(lambda x: x[0], values) |
paul@213 | 256 | else: |
paul@213 | 257 | return None |
paul@213 | 258 | |
paul@213 | 259 | def get_value(d, name): |
paul@213 | 260 | return get_values(d, name, False) |
paul@213 | 261 | |
paul@352 | 262 | def get_item_datetime_items(d, name): |
paul@352 | 263 | |
paul@352 | 264 | """ |
paul@352 | 265 | Return datetime items from 'd' having the given 'name', where a single item |
paul@352 | 266 | yields potentially many datetime values, each employing the attributes given |
paul@352 | 267 | for the principal item. |
paul@352 | 268 | """ |
paul@352 | 269 | |
paul@352 | 270 | item = get_item(d, name) |
paul@352 | 271 | if item: |
paul@352 | 272 | values, attr = item |
paul@352 | 273 | if not isinstance(values, list): |
paul@352 | 274 | values = [values] |
paul@352 | 275 | return [(get_datetime(value, attr), attr) for value in values] |
paul@352 | 276 | else: |
paul@352 | 277 | return None |
paul@352 | 278 | |
paul@213 | 279 | def get_utc_datetime(d, name): |
paul@348 | 280 | t = get_datetime_item(d, name) |
paul@348 | 281 | if not t: |
paul@348 | 282 | return None |
paul@348 | 283 | else: |
paul@348 | 284 | dt, attr = t |
paul@348 | 285 | return to_utc_datetime(dt) |
paul@289 | 286 | |
paul@289 | 287 | def get_datetime_item(d, name): |
paul@348 | 288 | t = get_item(d, name) |
paul@348 | 289 | if not t: |
paul@348 | 290 | return None |
paul@348 | 291 | else: |
paul@348 | 292 | value, attr = t |
paul@348 | 293 | return get_datetime(value, attr), attr |
paul@213 | 294 | |
paul@213 | 295 | def get_addresses(values): |
paul@213 | 296 | return [address for name, address in email.utils.getaddresses(values)] |
paul@213 | 297 | |
paul@213 | 298 | def get_address(value): |
paul@333 | 299 | value = value.lower() |
paul@333 | 300 | return value.startswith("mailto:") and value[7:] or value |
paul@213 | 301 | |
paul@213 | 302 | def get_uri(value): |
paul@213 | 303 | return value.lower().startswith("mailto:") and value.lower() or ":" in value and value or "mailto:%s" % value.lower() |
paul@213 | 304 | |
paul@309 | 305 | uri_value = get_uri |
paul@309 | 306 | |
paul@309 | 307 | def uri_values(values): |
paul@309 | 308 | return map(get_uri, values) |
paul@309 | 309 | |
paul@213 | 310 | def uri_dict(d): |
paul@213 | 311 | return dict([(get_uri(key), value) for key, value in d.items()]) |
paul@213 | 312 | |
paul@213 | 313 | def uri_item(item): |
paul@213 | 314 | return get_uri(item[0]), item[1] |
paul@213 | 315 | |
paul@213 | 316 | def uri_items(items): |
paul@213 | 317 | return [(get_uri(value), attr) for value, attr in items] |
paul@213 | 318 | |
paul@220 | 319 | # Operations on structure data. |
paul@220 | 320 | |
paul@220 | 321 | def is_new_object(old_sequence, new_sequence, old_dtstamp, new_dtstamp, partstat_set): |
paul@220 | 322 | |
paul@220 | 323 | """ |
paul@220 | 324 | Return for the given 'old_sequence' and 'new_sequence', 'old_dtstamp' and |
paul@220 | 325 | 'new_dtstamp', and the 'partstat_set' indication, whether the object |
paul@220 | 326 | providing the new information is really newer than the object providing the |
paul@220 | 327 | old information. |
paul@220 | 328 | """ |
paul@220 | 329 | |
paul@220 | 330 | have_sequence = old_sequence is not None and new_sequence is not None |
paul@220 | 331 | is_same_sequence = have_sequence and int(new_sequence) == int(old_sequence) |
paul@220 | 332 | |
paul@220 | 333 | have_dtstamp = old_dtstamp and new_dtstamp |
paul@220 | 334 | is_old_dtstamp = have_dtstamp and new_dtstamp < old_dtstamp or old_dtstamp and not new_dtstamp |
paul@220 | 335 | |
paul@220 | 336 | is_old_sequence = have_sequence and ( |
paul@220 | 337 | int(new_sequence) < int(old_sequence) or |
paul@220 | 338 | is_same_sequence and is_old_dtstamp |
paul@220 | 339 | ) |
paul@220 | 340 | |
paul@220 | 341 | return is_same_sequence and partstat_set or not is_old_sequence |
paul@220 | 342 | |
paul@256 | 343 | # NOTE: Need to expose the 100 day window for recurring events in the |
paul@256 | 344 | # NOTE: configuration. |
paul@256 | 345 | |
paul@360 | 346 | def get_window_end(tzid, window_size=100): |
paul@360 | 347 | return to_timezone(datetime.now(), tzid) + timedelta(window_size) |
paul@360 | 348 | |
paul@360 | 349 | def get_periods(obj, tzid, window_end, inclusive=False): |
paul@256 | 350 | |
paul@256 | 351 | """ |
paul@256 | 352 | Return periods for the given object 'obj', confining materialised periods |
paul@360 | 353 | to before the given 'window_end' datetime. If 'inclusive' is set to a true |
paul@360 | 354 | value, any period occurring at the 'window_end' will be included. |
paul@256 | 355 | """ |
paul@256 | 356 | |
paul@318 | 357 | rrule = obj.get_value("RRULE") |
paul@318 | 358 | |
paul@318 | 359 | # Use localised datetimes. |
paul@318 | 360 | |
paul@318 | 361 | dtstart, start_attr = obj.get_datetime_item("DTSTART") |
paul@318 | 362 | dtend, end_attr = obj.get_datetime_item("DTEND") |
paul@318 | 363 | tzid = start_attr.get("TZID") or end_attr.get("TZID") or tzid |
paul@256 | 364 | |
paul@256 | 365 | # NOTE: Need also DURATION support. |
paul@256 | 366 | |
paul@256 | 367 | duration = dtend - dtstart |
paul@256 | 368 | |
paul@352 | 369 | if not rrule: |
paul@352 | 370 | periods = [(dtstart, dtend)] |
paul@352 | 371 | else: |
paul@352 | 372 | # Recurrence rules create multiple instances to be checked. |
paul@352 | 373 | # Conflicts may only be assessed within a period defined by policy |
paul@352 | 374 | # for the agent, with instances outside that period being considered |
paul@352 | 375 | # unchecked. |
paul@352 | 376 | |
paul@352 | 377 | selector = get_rule(dtstart, rrule) |
paul@352 | 378 | parameters = get_parameters(rrule) |
paul@352 | 379 | periods = [] |
paul@352 | 380 | |
paul@360 | 381 | for start in selector.materialise(dtstart, window_end, parameters.get("COUNT"), parameters.get("BYSETPOS"), inclusive): |
paul@352 | 382 | start = to_timezone(datetime(*start), tzid) |
paul@352 | 383 | end = start + duration |
paul@352 | 384 | periods.append((start, end)) |
paul@352 | 385 | |
paul@352 | 386 | # Add recurrence dates. |
paul@256 | 387 | |
paul@352 | 388 | periods = set(periods) |
paul@352 | 389 | rdates = obj.get_item_datetimes("RDATE") |
paul@352 | 390 | |
paul@352 | 391 | if rdates: |
paul@352 | 392 | for rdate in rdates: |
paul@352 | 393 | periods.add((rdate, rdate + duration)) |
paul@352 | 394 | |
paul@352 | 395 | # Exclude exception dates. |
paul@352 | 396 | |
paul@352 | 397 | exdates = obj.get_item_datetimes("EXDATE") |
paul@256 | 398 | |
paul@352 | 399 | if exdates: |
paul@352 | 400 | for exdate in exdates: |
paul@352 | 401 | period = (exdate, exdate + duration) |
paul@352 | 402 | if period in periods: |
paul@352 | 403 | periods.remove(period) |
paul@256 | 404 | |
paul@352 | 405 | # Return a sorted list of the periods. |
paul@352 | 406 | |
paul@352 | 407 | periods = list(periods) |
paul@352 | 408 | periods.sort() |
paul@256 | 409 | return periods |
paul@256 | 410 | |
paul@291 | 411 | def get_periods_for_freebusy(obj, periods, tzid): |
paul@291 | 412 | |
paul@306 | 413 | """ |
paul@306 | 414 | Get free/busy-compliant periods employed by 'obj' from the given 'periods', |
paul@306 | 415 | using the indicated 'tzid' to convert dates to datetimes. |
paul@306 | 416 | """ |
paul@306 | 417 | |
paul@291 | 418 | start, start_attr = obj.get_datetime_item("DTSTART") |
paul@291 | 419 | end, end_attr = obj.get_datetime_item("DTEND") |
paul@291 | 420 | |
paul@291 | 421 | tzid = start_attr.get("TZID") or end_attr.get("TZID") or tzid |
paul@291 | 422 | |
paul@291 | 423 | l = [] |
paul@291 | 424 | |
paul@291 | 425 | for start, end in periods: |
paul@291 | 426 | start, end = get_freebusy_period(start, end, tzid) |
paul@320 | 427 | start, end = [to_timezone(x, "UTC") for x in start, end] |
paul@291 | 428 | l.append((format_datetime(start), format_datetime(end))) |
paul@291 | 429 | |
paul@291 | 430 | return l |
paul@291 | 431 | |
paul@213 | 432 | # vim: tabstop=4 expandtab shiftwidth=4 |