| 1 | # python-mpd: Python MPD client library |
| 2 | # Copyright (C) 2008-2010 J. Alexander Treuman <jat@spatialrift.net> |
| 3 | # |
| 4 | # python-mpd is free software: you can redistribute it and/or modify |
| 5 | # it under the terms of the GNU Lesser General Public License as published by |
| 6 | # the Free Software Foundation, either version 3 of the License, or |
| 7 | # (at your option) any later version. |
| 8 | # |
| 9 | # python-mpd is distributed in the hope that it will be useful, |
| 10 | # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 12 | # GNU Lesser General Public License for more details. |
| 13 | # |
| 14 | # You should have received a copy of the GNU Lesser General Public License |
| 15 | # along with python-mpd. If not, see <http://www.gnu.org/licenses/>. |
| 16 | |
| 17 | import socket |
| 18 | |
| 19 | |
| 20 | HELLO_PREFIX = "OK MPD " |
| 21 | ERROR_PREFIX = "ACK " |
| 22 | SUCCESS = "OK" |
| 23 | NEXT = "list_OK" |
| 24 | |
| 25 | |
| 26 | class MPDError(Exception): |
| 27 | pass |
| 28 | |
| 29 | class ConnectionError(MPDError): |
| 30 | pass |
| 31 | |
| 32 | class ProtocolError(MPDError): |
| 33 | pass |
| 34 | |
| 35 | class CommandError(MPDError): |
| 36 | pass |
| 37 | |
| 38 | class CommandListError(MPDError): |
| 39 | pass |
| 40 | |
| 41 | class PendingCommandError(MPDError): |
| 42 | pass |
| 43 | |
| 44 | class IteratingError(MPDError): |
| 45 | pass |
| 46 | |
| 47 | |
| 48 | class _NotConnected(object): |
| 49 | def __getattr__(self, attr): |
| 50 | return self._dummy |
| 51 | |
| 52 | def _dummy(*args): |
| 53 | raise ConnectionError("Not connected") |
| 54 | |
| 55 | class MPDClient(object): |
| 56 | def __init__(self): |
| 57 | self.iterate = False |
| 58 | self._reset() |
| 59 | self._commands = { |
| 60 | # Status Commands |
| 61 | "clearerror": self._fetch_nothing, |
| 62 | "currentsong": self._fetch_object, |
| 63 | "idle": self._fetch_list, |
| 64 | "noidle": None, |
| 65 | "status": self._fetch_object, |
| 66 | "stats": self._fetch_object, |
| 67 | # Playback Option Commands |
| 68 | "consume": self._fetch_nothing, |
| 69 | "crossfade": self._fetch_nothing, |
| 70 | "mixrampdb": self._fetch_nothing, |
| 71 | "mixrampdelay": self._fetch_nothing, |
| 72 | "random": self._fetch_nothing, |
| 73 | "repeat": self._fetch_nothing, |
| 74 | "setvol": self._fetch_nothing, |
| 75 | "single": self._fetch_nothing, |
| 76 | "replay_gain_mode": self._fetch_nothing, |
| 77 | "replay_gain_status": self._fetch_item, |
| 78 | "volume": self._fetch_nothing, |
| 79 | # Playback Control Commands |
| 80 | "next": self._fetch_nothing, |
| 81 | "pause": self._fetch_nothing, |
| 82 | "play": self._fetch_nothing, |
| 83 | "playid": self._fetch_nothing, |
| 84 | "previous": self._fetch_nothing, |
| 85 | "seek": self._fetch_nothing, |
| 86 | "seekid": self._fetch_nothing, |
| 87 | "stop": self._fetch_nothing, |
| 88 | # Playlist Commands |
| 89 | "add": self._fetch_nothing, |
| 90 | "addid": self._fetch_item, |
| 91 | "clear": self._fetch_nothing, |
| 92 | "delete": self._fetch_nothing, |
| 93 | "deleteid": self._fetch_nothing, |
| 94 | "move": self._fetch_nothing, |
| 95 | "moveid": self._fetch_nothing, |
| 96 | "playlist": self._fetch_playlist, |
| 97 | "playlistfind": self._fetch_songs, |
| 98 | "playlistid": self._fetch_songs, |
| 99 | "playlistinfo": self._fetch_songs, |
| 100 | "playlistsearch": self._fetch_songs, |
| 101 | "plchanges": self._fetch_songs, |
| 102 | "plchangesposid": self._fetch_changes, |
| 103 | "shuffle": self._fetch_nothing, |
| 104 | "swap": self._fetch_nothing, |
| 105 | "swapid": self._fetch_nothing, |
| 106 | # Stored Playlist Commands |
| 107 | "listplaylist": self._fetch_list, |
| 108 | "listplaylistinfo": self._fetch_songs, |
| 109 | "listplaylists": self._fetch_playlists, |
| 110 | "load": self._fetch_nothing, |
| 111 | "playlistadd": self._fetch_nothing, |
| 112 | "playlistclear": self._fetch_nothing, |
| 113 | "playlistdelete": self._fetch_nothing, |
| 114 | "playlistmove": self._fetch_nothing, |
| 115 | "rename": self._fetch_nothing, |
| 116 | "rm": self._fetch_nothing, |
| 117 | "save": self._fetch_nothing, |
| 118 | # Database Commands |
| 119 | "count": self._fetch_object, |
| 120 | "find": self._fetch_songs, |
| 121 | "findadd": self._fetch_nothing, |
| 122 | "list": self._fetch_list, |
| 123 | "listall": self._fetch_database, |
| 124 | "listallinfo": self._fetch_database, |
| 125 | "lsinfo": self._fetch_database, |
| 126 | "search": self._fetch_songs, |
| 127 | "update": self._fetch_item, |
| 128 | "rescan": self._fetch_item, |
| 129 | # Sticker Commands |
| 130 | "sticker get": self._fetch_item, |
| 131 | "sticker set": self._fetch_nothing, |
| 132 | "sticker delete": self._fetch_nothing, |
| 133 | "sticker list": self._fetch_list, |
| 134 | "sticker find": self._fetch_songs, |
| 135 | # Connection Commands |
| 136 | "close": None, |
| 137 | "kill": None, |
| 138 | "password": self._fetch_nothing, |
| 139 | "ping": self._fetch_nothing, |
| 140 | # Audio Output Commands |
| 141 | "disableoutput": self._fetch_nothing, |
| 142 | "enableoutput": self._fetch_nothing, |
| 143 | "outputs": self._fetch_outputs, |
| 144 | # Reflection Commands |
| 145 | "commands": self._fetch_list, |
| 146 | "notcommands": self._fetch_list, |
| 147 | "tagtypes": self._fetch_list, |
| 148 | "urlhandlers": self._fetch_list, |
| 149 | "decoders": self._fetch_plugins, |
| 150 | } |
| 151 | |
| 152 | def __getattr__(self, attr): |
| 153 | if attr.startswith("send_"): |
| 154 | command = attr.replace("send_", "", 1) |
| 155 | wrapper = self._send |
| 156 | elif attr.startswith("fetch_"): |
| 157 | command = attr.replace("fetch_", "", 1) |
| 158 | wrapper = self._fetch |
| 159 | else: |
| 160 | command = attr |
| 161 | wrapper = self._execute |
| 162 | if command not in self._commands: |
| 163 | command = command.replace("_", " ") |
| 164 | if command not in self._commands: |
| 165 | raise AttributeError("'%s' object has no attribute '%s'" % |
| 166 | (self.__class__.__name__, attr)) |
| 167 | return lambda *args: wrapper(command, args) |
| 168 | |
| 169 | def _send(self, command, args): |
| 170 | if self._command_list is not None: |
| 171 | raise CommandListError("Cannot use send_%s in a command list" % |
| 172 | command.replace(" ", "_")) |
| 173 | self._write_command(command, args) |
| 174 | retval = self._commands[command] |
| 175 | if retval is not None: |
| 176 | self._pending.append(command) |
| 177 | |
| 178 | def _fetch(self, command, args=None): |
| 179 | if self._command_list is not None: |
| 180 | raise CommandListError("Cannot use fetch_%s in a command list" % |
| 181 | command.replace(" ", "_")) |
| 182 | if self._iterating: |
| 183 | raise IteratingError("Cannot use fetch_%s while iterating" % |
| 184 | command.replace(" ", "_")) |
| 185 | if not self._pending: |
| 186 | raise PendingCommandError("No pending commands to fetch") |
| 187 | if self._pending[0] != command: |
| 188 | raise PendingCommandError("'%s' is not the currently " |
| 189 | "pending command" % command) |
| 190 | del self._pending[0] |
| 191 | retval = self._commands[command] |
| 192 | if callable(retval): |
| 193 | return retval() |
| 194 | return retval |
| 195 | |
| 196 | def _execute(self, command, args): |
| 197 | if self._iterating: |
| 198 | raise IteratingError("Cannot execute '%s' while iterating" % |
| 199 | command) |
| 200 | if self._pending: |
| 201 | raise PendingCommandError("Cannot execute '%s' with " |
| 202 | "pending commands" % command) |
| 203 | retval = self._commands[command] |
| 204 | if self._command_list is not None: |
| 205 | if not callable(retval): |
| 206 | raise CommandListError("'%s' not allowed in command list" % |
| 207 | command) |
| 208 | self._write_command(command, args) |
| 209 | self._command_list.append(retval) |
| 210 | else: |
| 211 | self._write_command(command, args) |
| 212 | if callable(retval): |
| 213 | return retval() |
| 214 | return retval |
| 215 | |
| 216 | def _write_line(self, line): |
| 217 | self._wfile.write("%s\n" % line) |
| 218 | self._wfile.flush() |
| 219 | |
| 220 | def _write_command(self, command, args=[]): |
| 221 | parts = [command] |
| 222 | for arg in args: |
| 223 | parts.append('"%s"' % escape(str(arg))) |
| 224 | self._write_line(" ".join(parts)) |
| 225 | |
| 226 | def _read_line(self): |
| 227 | line = self._rfile.readline() |
| 228 | if not line.endswith("\n"): |
| 229 | raise ConnectionError("Connection lost while reading line") |
| 230 | line = line.rstrip("\n") |
| 231 | if line.startswith(ERROR_PREFIX): |
| 232 | error = line[len(ERROR_PREFIX):].strip() |
| 233 | raise CommandError(error) |
| 234 | if self._command_list is not None: |
| 235 | if line == NEXT: |
| 236 | return |
| 237 | if line == SUCCESS: |
| 238 | raise ProtocolError("Got unexpected '%s'" % SUCCESS) |
| 239 | elif line == SUCCESS: |
| 240 | return |
| 241 | return line |
| 242 | |
| 243 | def _read_pair(self, separator): |
| 244 | line = self._read_line() |
| 245 | if line is None: |
| 246 | return |
| 247 | pair = line.split(separator, 1) |
| 248 | if len(pair) < 2: |
| 249 | raise ProtocolError("Could not parse pair: '%s'" % line) |
| 250 | return pair |
| 251 | |
| 252 | def _read_pairs(self, separator=": "): |
| 253 | pair = self._read_pair(separator) |
| 254 | while pair: |
| 255 | yield pair |
| 256 | pair = self._read_pair(separator) |
| 257 | |
| 258 | def _read_list(self): |
| 259 | seen = None |
| 260 | for key, value in self._read_pairs(): |
| 261 | if key != seen: |
| 262 | if seen is not None: |
| 263 | raise ProtocolError("Expected key '%s', got '%s'" % |
| 264 | (seen, key)) |
| 265 | seen = key |
| 266 | yield value |
| 267 | |
| 268 | def _read_playlist(self): |
| 269 | for key, value in self._read_pairs(":"): |
| 270 | yield value |
| 271 | |
| 272 | def _read_objects(self, delimiters=[]): |
| 273 | obj = {} |
| 274 | for key, value in self._read_pairs(): |
| 275 | key = key.lower() |
| 276 | if obj: |
| 277 | if key in delimiters: |
| 278 | yield obj |
| 279 | obj = {} |
| 280 | elif key in obj: |
| 281 | if not isinstance(obj[key], list): |
| 282 | obj[key] = [obj[key], value] |
| 283 | else: |
| 284 | obj[key].append(value) |
| 285 | continue |
| 286 | obj[key] = value |
| 287 | if obj: |
| 288 | yield obj |
| 289 | |
| 290 | def _read_command_list(self): |
| 291 | try: |
| 292 | for retval in self._command_list: |
| 293 | yield retval() |
| 294 | finally: |
| 295 | self._command_list = None |
| 296 | self._fetch_nothing() |
| 297 | |
| 298 | def _iterator_wrapper(self, iterator): |
| 299 | try: |
| 300 | for item in iterator: |
| 301 | yield item |
| 302 | finally: |
| 303 | self._iterating = False |
| 304 | |
| 305 | def _wrap_iterator(self, iterator): |
| 306 | if not self.iterate: |
| 307 | return list(iterator) |
| 308 | self._iterating = True |
| 309 | return self._iterator_wrapper(iterator) |
| 310 | |
| 311 | def _fetch_nothing(self): |
| 312 | line = self._read_line() |
| 313 | if line is not None: |
| 314 | raise ProtocolError("Got unexpected return value: '%s'" % line) |
| 315 | |
| 316 | def _fetch_item(self): |
| 317 | pairs = list(self._read_pairs()) |
| 318 | if len(pairs) != 1: |
| 319 | return |
| 320 | return pairs[0][1] |
| 321 | |
| 322 | def _fetch_list(self): |
| 323 | return self._wrap_iterator(self._read_list()) |
| 324 | |
| 325 | def _fetch_playlist(self): |
| 326 | return self._wrap_iterator(self._read_playlist()) |
| 327 | |
| 328 | def _fetch_object(self): |
| 329 | objs = list(self._read_objects()) |
| 330 | if not objs: |
| 331 | return {} |
| 332 | return objs[0] |
| 333 | |
| 334 | def _fetch_objects(self, delimiters): |
| 335 | return self._wrap_iterator(self._read_objects(delimiters)) |
| 336 | |
| 337 | def _fetch_changes(self): |
| 338 | return self._fetch_objects(["cpos"]) |
| 339 | |
| 340 | def _fetch_songs(self): |
| 341 | return self._fetch_objects(["file"]) |
| 342 | |
| 343 | def _fetch_playlists(self): |
| 344 | return self._fetch_objects(["playlist"]) |
| 345 | |
| 346 | def _fetch_database(self): |
| 347 | return self._fetch_objects(["file", "directory", "playlist"]) |
| 348 | |
| 349 | def _fetch_outputs(self): |
| 350 | return self._fetch_objects(["outputid"]) |
| 351 | |
| 352 | def _fetch_plugins(self): |
| 353 | return self._fetch_objects(["plugin"]) |
| 354 | |
| 355 | def _fetch_command_list(self): |
| 356 | return self._wrap_iterator(self._read_command_list()) |
| 357 | |
| 358 | def _hello(self): |
| 359 | line = self._rfile.readline() |
| 360 | if not line.endswith("\n"): |
| 361 | raise ConnectionError("Connection lost while reading MPD hello") |
| 362 | line = line.rstrip("\n") |
| 363 | if not line.startswith(HELLO_PREFIX): |
| 364 | raise ProtocolError("Got invalid MPD hello: '%s'" % line) |
| 365 | self.mpd_version = line[len(HELLO_PREFIX):].strip() |
| 366 | |
| 367 | def _reset(self): |
| 368 | self.mpd_version = None |
| 369 | self._iterating = False |
| 370 | self._pending = [] |
| 371 | self._command_list = None |
| 372 | self._sock = None |
| 373 | self._rfile = _NotConnected() |
| 374 | self._wfile = _NotConnected() |
| 375 | |
| 376 | def _connect_unix(self, path): |
| 377 | if not hasattr(socket, "AF_UNIX"): |
| 378 | raise ConnectionError("Unix domain sockets not supported " |
| 379 | "on this platform") |
| 380 | sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) |
| 381 | sock.connect(path) |
| 382 | return sock |
| 383 | |
| 384 | def _connect_tcp(self, host, port): |
| 385 | try: |
| 386 | flags = socket.AI_ADDRCONFIG |
| 387 | except AttributeError: |
| 388 | flags = 0 |
| 389 | err = None |
| 390 | for res in socket.getaddrinfo(host, port, socket.AF_UNSPEC, |
| 391 | socket.SOCK_STREAM, socket.IPPROTO_TCP, |
| 392 | flags): |
| 393 | af, socktype, proto, canonname, sa = res |
| 394 | sock = None |
| 395 | try: |
| 396 | sock = socket.socket(af, socktype, proto) |
| 397 | sock.connect(sa) |
| 398 | return sock |
| 399 | except socket.error, err: |
| 400 | if sock is not None: |
| 401 | sock.close() |
| 402 | if err is not None: |
| 403 | raise err |
| 404 | else: |
| 405 | raise ConnectionError("getaddrinfo returns an empty list") |
| 406 | |
| 407 | def connect(self, host, port): |
| 408 | if self._sock is not None: |
| 409 | raise ConnectionError("Already connected") |
| 410 | if host.startswith("/"): |
| 411 | self._sock = self._connect_unix(host) |
| 412 | else: |
| 413 | self._sock = self._connect_tcp(host, port) |
| 414 | self._rfile = self._sock.makefile("rb") |
| 415 | self._wfile = self._sock.makefile("wb") |
| 416 | try: |
| 417 | self._hello() |
| 418 | except: |
| 419 | self.disconnect() |
| 420 | raise |
| 421 | |
| 422 | def disconnect(self): |
| 423 | self._rfile.close() |
| 424 | self._wfile.close() |
| 425 | self._sock.close() |
| 426 | self._reset() |
| 427 | |
| 428 | def fileno(self): |
| 429 | if self._sock is None: |
| 430 | raise ConnectionError("Not connected") |
| 431 | return self._sock.fileno() |
| 432 | |
| 433 | def command_list_ok_begin(self): |
| 434 | if self._command_list is not None: |
| 435 | raise CommandListError("Already in command list") |
| 436 | if self._iterating: |
| 437 | raise IteratingError("Cannot begin command list while iterating") |
| 438 | if self._pending: |
| 439 | raise PendingCommandError("Cannot begin command list " |
| 440 | "with pending commands") |
| 441 | self._write_command("command_list_ok_begin") |
| 442 | self._command_list = [] |
| 443 | |
| 444 | def command_list_end(self): |
| 445 | if self._command_list is None: |
| 446 | raise CommandListError("Not in command list") |
| 447 | if self._iterating: |
| 448 | raise IteratingError("Already iterating over a command list") |
| 449 | self._write_command("command_list_end") |
| 450 | return self._fetch_command_list() |
| 451 | |
| 452 | |
| 453 | def escape(text): |
| 454 | return text.replace("\\", "\\\\").replace('"', '\\"') |
| 455 | |
| 456 | |
| 457 | # vim: set expandtab shiftwidth=4 softtabstop=4 textwidth=79: |
| 458 | |
