initial commit

diff --git a/mpd.py b/mpd.py
new file mode 100644 (file)
index 0000000..7e92cc0
--- /dev/null
+++ b/mpd.py
@@ -0,0 +1,259 @@
+#! /usr/bin/env python
+
+# TODO: return {} if no object read (?)
+# TODO: implement argument checking/parsing (?)
+# TODO: check for EOF when reading and benchmark it
+# TODO: command_list support
+# TODO: converter support
+# TODO: global for parsing MPD_HOST/MPD_PORT
+# TODO: global for parsing MPD error messages
+# TODO: IPv6 support (AF_INET6)
+
+import socket
+
+
+HELLO_PREFIX = "OK MPD "
+ERROR_PREFIX = "ACK "
+SUCCESS = "OK"
+
+
+class MPDError(Exception):
+    pass
+
+class ProtocolError(MPDError):
+    pass
+
+class CommandError(MPDError):
+    pass
+
+
+class MPDClient(object):
+    def __init__(self):
+        self.iterate = False
+        self._reset()
+        self._commands = {
+            # Admin Commands
+            "disableoutput":    self._getnone,
+            "enableoutput":     self._getnone,
+            "kill":             None,
+            "update":           self._getitem,
+            # Informational Commands
+            "status":           self._getobject,
+            "stats":            self._getobject,
+            "outputs":          self._getoutputs,
+            "commands":         self._getlist,
+            "notcommands":      self._getlist,
+            "tagtypes":         self._getlist,
+            "urlhandlers":      self._getlist,
+            # Database Commands
+            "find":             self._getsongs,
+            "list":             self._getlist,
+            "listall":          self._getdatabase,
+            "listallinfo":      self._getdatabase,
+            "lsinfo":           self._getdatabase,
+            "search":           self._getsongs,
+            "count":            self._getobject,
+            # Playlist Commands
+            "add":              self._getnone,
+            "addid":            self._getitem,
+            "clear":            self._getnone,
+            "currentsong":      self._getobject,
+            "delete":           self._getnone,
+            "deleteid":         self._getnone,
+            "load":             self._getnone,
+            "rename":           self._getnone,
+            "move":             self._getnone,
+            "moveid":           self._getnone,
+            "playlist":         self._getplaylist,
+            "playlistinfo":     self._getsongs,
+            "playlistid":       self._getsongs,
+            "plchanges":        self._getsongs,
+            "plchangesposid":   self._getchanges,
+            "rm":               self._getnone,
+            "save":             self._getnone,
+            "shuffle":          self._getnone,
+            "swap":             self._getnone,
+            "swapid":           self._getnone,
+            "listplaylist":     self._getlist,
+            "listplaylistinfo": self._getsongs,
+            "playlistadd":      self._getnone,
+            "playlistclear":    self._getnone,
+            "playlistdelete":   self._getnone,
+            "playlistmove":     self._getnone,
+            "playlistfind":     self._getsongs,
+            "playlistsearch":   self._getsongs,
+            # Playback Commands
+            "crossfade":        self._getnone,
+            "next":             self._getnone,
+            "pause":            self._getnone,
+            "play":             self._getnone,
+            "playid":           self._getnone,
+            "previous":         self._getnone,
+            "random":           self._getnone,
+            "repeat":           self._getnone,
+            "seek":             self._getnone,
+            "seekid":           self._getnone,
+            "setvol":           self._getnone,
+            "stop":             self._getnone,
+            "volume":           self._getnone,
+            # Miscellaneous Commands
+            "clearerror":       self._getnone,
+            "close":            None,
+            "password":         self._getnone,
+            "ping":             self._getnone,
+        }
+
+    def __getattr__(self, attr):
+        try:
+            retval = self._commands[attr]
+        except KeyError:
+            raise AttributeError, "'%s' object has no attribute '%s'" % \
+                                  (self.__class__.__name__, attr)
+        return lambda *args: self._docommand(attr, args, retval)
+
+    def _docommand(self, command, args, retval):
+        self._writecommand(command, args)
+        if callable(retval):
+            return retval()
+        return retval
+
+    def _writeline(self, line):
+        self._sockfile.write("%s\n" % line)
+        self._sockfile.flush()
+
+    def _writecommand(self, command, args):
+        parts = [command]
+        for arg in args:
+            parts.append('"%s"' % escape(str(arg)))
+        self._writeline(" ".join(parts))
+
+    def _readline(self):
+        line = self._sockfile.readline().rstrip("\n")
+        if line.startswith(ERROR_PREFIX):
+            error = line[len(ERROR_PREFIX):].strip()
+            raise CommandError, error
+        if line == SUCCESS:
+            return
+        return line
+
+    def _readitem(self, separator):
+        line = self._readline()
+        if line is None:
+            return
+        item = line.split(separator, 1)
+        if len(item) < 2:
+            raise ProtocolError, "Could not parse item: '%s'" % line
+        return item
+
+    def _readitems(self, separator=": "):
+        item = self._readitem(separator)
+        while item:
+            yield item
+            item = self._readitem(separator)
+        raise StopIteration
+
+    def _readlist(self):
+        seen = None
+        for key, value in self._readitems():
+            if key != seen:
+                if seen is not None:
+                    raise ProtocolError, "Expected key '%s', got '%s'" % \
+                                         (seen, key)
+                seen = key
+            yield value
+        raise StopIteration
+
+    def _readplaylist(self):
+        for key, value in self._readitems(":"):
+            yield value
+        raise StopIteration
+
+    def _readobjects(self, delimiters=[]):
+        obj = {}
+        for key, value in self._readitems():
+            key = key.lower()
+            if obj:
+                if key in delimiters:
+                    yield obj
+                    obj = {}
+                elif obj.has_key(key):
+                    if not isinstance(obj[key], list):
+                        obj[key] = [obj[key], value]
+                    else:
+                        obj[key].append(value)
+                    continue
+            obj[key] = value
+        if obj:
+            yield obj
+        raise StopIteration
+
+    def _wrapiterator(self, iterator):
+        if not self.iterate:
+            return list(iterator)
+        return iterator
+
+    def _getnone(self):
+        line = self._readline()
+        if line is not None:
+            raise ProtocolError, "Got unexpected return value: '%s'" % line
+
+    def _getitem(self):
+        items = list(self._readitems())
+        if len(items) != 1:
+            raise ProtocolError, "Expected 1 item, got %i" % len(items)
+        return items[0][1]
+
+    def _getlist(self):
+        return self._wrapiterator(self._readlist())
+
+    def _getplaylist(self):
+        return self._wrapiterator(self._readplaylist())
+
+    def _getobject(self):
+        objs = list(self._readobjects())
+        if not objs:
+            return
+        return objs[0]
+
+    def _getobjects(self, delimiters):
+        return self._wrapiterator(self._readobjects(delimiters))
+
+    def _getsongs(self):
+        return self._getobjects(["file"])
+
+    def _getdatabase(self):
+        return self._getobjects(["file", "directory", "playlist"])
+
+    def _getoutputs(self):
+        return self._getobjects(["outputid"])
+
+    def _getchanges(self):
+        return self._getobjects(["cpos"])
+
+    def _hello(self):
+        line = self._sockfile.readline().rstrip("\n")
+        if not line.startswith(HELLO_PREFIX):
+            raise ProtocolError, "Got invalid MPD hello: '%s'" % line
+        self.mpd_version = line[len(HELLO_PREFIX):].strip()
+
+    def _reset(self):
+        self.mpd_version = None
+        self._sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self._sockfile = self._sock.makefile("rb+")
+
+    def connect(self, host, port):
+        self.disconnect()
+        self._sock.connect((host, port))
+        self._hello()
+
+    def disconnect(self):
+        self._sockfile.close()
+        self._sock.close()
+        self._reset()
+
+
+def escape(text):
+    return text.replace("\\", "\\\\").replace('"', '\\"')
+
+
+# vim: set expandtab shiftwidth=4 softtabstop=4 textwidth=79: