1 #!/usr/bin/env python 2 3 """ 4 A processing framework for iMIP content. 5 6 Copyright (C) 2014, 2015 Paul Boddie <paul@boddie.org.uk> 7 8 This program is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free Software 10 Foundation; either version 3 of the License, or (at your option) any later 11 version. 12 13 This program is distributed in the hope that it will be useful, but WITHOUT 14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 15 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 16 details. 17 18 You should have received a copy of the GNU General Public License along with 19 this program. If not, see <http://www.gnu.org/licenses/>. 20 """ 21 22 from email import message_from_file 23 from imiptools.content import handle_itip_part 24 from imiptools.data import get_addresses, get_uri, make_freebusy, to_part 25 from imiptools.dates import get_timestamp 26 from imiptools.mail import Messenger 27 from imiptools.profile import Preferences 28 import imip_store 29 import sys 30 31 # Postfix exit codes. 32 33 EX_TEMPFAIL = 75 34 35 # Permitted iTIP content types. 36 37 itip_content_types = [ 38 "text/calendar", # from RFC 6047 39 "text/x-vcalendar", "application/ics", # other possibilities 40 ] 41 42 # Processing of incoming messages. 43 44 def get_all_values(msg, key): 45 l = [] 46 for v in msg.get_all(key) or []: 47 l += [s.strip() for s in v.split(",")] 48 return l 49 50 class Processor: 51 52 "The processing framework." 53 54 def __init__(self, handlers, messenger=None): 55 self.handlers = handlers 56 self.messenger = messenger or Messenger() 57 self.lmtp_socket = None 58 59 def process(self, f, original_recipients, outgoing_only): 60 61 """ 62 Process content from the stream 'f' accompanied by the given 63 'original_recipients'. 64 """ 65 66 msg = message_from_file(f) 67 senders = get_addresses(msg.get_all("Reply-To") or msg.get_all("From") or []) 68 69 # Handle messages with iTIP parts. 70 # Typically, the details of recipients are of interest in handling 71 # messages. 72 73 if not outgoing_only: 74 original_recipients = original_recipients or get_addresses(get_all_values(msg, "To") or []) 75 for recipient in original_recipients: 76 self.process_for_recipient(msg, recipient, senders, outgoing_only) 77 78 # However, outgoing messages do not usually presume anything about the 79 # eventual recipients. 80 81 else: 82 self.process_for_recipient(msg, None, senders, outgoing_only) 83 84 def process_for_recipient(self, msg, recipient, senders, outgoing_only): 85 86 """ 87 Process the given 'msg' for a single 'recipient', having the given 88 'senders', and with the given 'outgoing_only' status. 89 90 Processing individually means that contributions to resulting messages 91 may be constructed according to individual preferences. 92 """ 93 94 handlers = dict([(name, cls(senders, recipient, self.messenger)) for name, cls in self.handlers]) 95 handled = False 96 97 for part in msg.walk(): 98 if part.get_content_type() in itip_content_types and \ 99 part.get_param("method"): 100 101 handle_itip_part(part, handlers) 102 handled = True 103 104 # When processing outgoing messages, no replies or deliveries are 105 # performed. 106 107 if outgoing_only: 108 return 109 110 # Get responses from the handlers. 111 112 all_responses = [] 113 for handler in handlers.values(): 114 all_responses += handler.get_results() 115 116 # Pack any returned parts into messages. 117 118 if all_responses: 119 outgoing_parts = {} 120 forwarded_parts = [] 121 122 for outgoing_recipients, part in all_responses: 123 if outgoing_recipients: 124 for outgoing_recipient in outgoing_recipients: 125 if not outgoing_parts.has_key(outgoing_recipient): 126 outgoing_parts[outgoing_recipient] = [] 127 outgoing_parts[outgoing_recipient].append(part) 128 else: 129 forwarded_parts.append(part) 130 131 # Reply using any outgoing parts in a new message. 132 133 if outgoing_parts: 134 135 # Obtain free/busy details, if configured to do so. 136 137 fb = self.can_provide_freebusy(handlers) and self.get_freebusy_for_recipient(recipient) 138 139 for outgoing_recipient, parts in outgoing_parts.items(): 140 141 # Bundle free/busy messages, if configured to do so. 142 143 if fb: parts.append(fb) 144 message = self.messenger.make_outgoing_message(parts, [outgoing_recipient]) 145 146 if "-d" in sys.argv: 147 print >>sys.stderr, "Outgoing parts for %s..." % outgoing_recipient 148 print message 149 else: 150 self.messenger.sendmail([outgoing_recipient], message.as_string()) 151 152 # Forward messages to their recipients either wrapping the existing 153 # message, accompanying it or replacing it. 154 155 if forwarded_parts: 156 157 # Determine whether to wrap, accompany or replace the message. 158 159 preferences = Preferences(get_uri(recipient)) 160 161 incoming = preferences.get("incoming") 162 163 if incoming == "message-only": 164 messages = [msg] 165 else: 166 summary = self.messenger.make_summary_message(msg, forwarded_parts) 167 if incoming == "summary-then-message": 168 messages = [summary, msg] 169 elif incoming == "message-then-summary": 170 messages = [msg, summary] 171 elif incoming == "summary-only": 172 messages = [summary] 173 else: # incoming == "summary-wraps-message": 174 messages = [self.messenger.wrap_message(msg, forwarded_parts)] 175 176 for message in messages: 177 if "-d" in sys.argv: 178 print >>sys.stderr, "Forwarded parts..." 179 print message 180 elif self.lmtp_socket: 181 self.messenger.sendmail(recipient, message.as_string(), lmtp_socket=self.lmtp_socket) 182 183 # Unhandled messages are delivered as they are. 184 185 if not handled: 186 if "-d" in sys.argv: 187 print >>sys.stderr, "Unhandled parts..." 188 print msg 189 elif self.lmtp_socket: 190 self.messenger.sendmail(recipient, msg.as_string(), lmtp_socket=self.lmtp_socket) 191 192 def can_provide_freebusy(self, handlers): 193 194 "Test for any free/busy information produced by 'handlers'." 195 196 fbhandler = handlers.get("VFREEBUSY") 197 if fbhandler: 198 fbmethods = fbhandler.get_outgoing_methods() 199 return not "REPLY" in fbmethods and not "PUBLISH" in fbmethods 200 else: 201 return False 202 203 def get_freebusy_for_recipient(self, recipient): 204 205 """ 206 Return a list of responses containing free/busy information for the 207 given 'recipient'. 208 """ 209 210 organiser = get_uri(recipient) 211 preferences = Preferences(organiser) 212 213 organiser_attr = self.messenger and {"SENT-BY" : get_uri(self.messenger.sender)} or {} 214 215 if preferences.get("freebusy_sharing") == "share" and \ 216 preferences.get("freebusy_bundling") == "always": 217 218 # Invent a unique identifier. 219 220 utcnow = get_timestamp() 221 uid = "imip-agent-%s-%s" % (utcnow, recipient) 222 223 freebusy = imip_store.FileStore().get_freebusy(organiser) 224 return to_part("PUBLISH", [make_freebusy(freebusy, uid, organiser, organiser_attr)]) 225 226 return None 227 228 def process_args(self, args, stream): 229 230 """ 231 Interpret the given program arguments 'args' and process input from the 232 given 'stream'. 233 """ 234 235 # Obtain the different kinds of recipients plus sender address. 236 237 original_recipients = [] 238 recipients = [] 239 senders = [] 240 lmtp = [] 241 outgoing_only = False 242 243 l = [] 244 245 for arg in args: 246 247 # Detect outgoing processing mode. 248 249 if arg == "-O": 250 outgoing_only = True 251 252 # Switch to collecting recipients. 253 254 if arg == "-o": 255 l = original_recipients 256 257 # Switch to collecting senders. 258 259 elif arg == "-s": 260 l = senders 261 262 # Switch to getting the LMTP socket. 263 264 elif arg == "-l": 265 l = lmtp 266 267 # Ignore debugging options. 268 269 elif arg == "-d": 270 pass 271 else: 272 l.append(arg) 273 274 self.messenger.sender = senders and senders[0] or self.messenger.sender 275 self.lmtp_socket = lmtp and lmtp[0] or None 276 self.process(stream, original_recipients, outgoing_only) 277 278 def __call__(self): 279 280 """ 281 Obtain arguments from the command line to initialise the processor 282 before invoking it. 283 """ 284 285 args = sys.argv[1:] 286 287 if "-d" in args: 288 self.process_args(args, sys.stdin) 289 else: 290 try: 291 self.process_args(args, sys.stdin) 292 except SystemExit, value: 293 sys.exit(value) 294 except Exception, exc: 295 if "-v" in args: 296 raise 297 type, value, tb = sys.exc_info() 298 while tb.tb_next: 299 tb = tb.tb_next 300 f = tb.tb_frame 301 co = f and f.f_code 302 filename = co and co.co_filename 303 print >>sys.stderr, "Exception %s at %d in %s" % (exc, tb.tb_lineno, filename) 304 #import traceback 305 #traceback.print_exc(file=open("/tmp/mail.log", "a")) 306 sys.exit(EX_TEMPFAIL) 307 sys.exit(0) 308 309 # 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