begin adding convenient plugin defaults

We need plugins to set their config values at run time instead of module import
time. That is, defaults should be put in the __init__ method. This is easy
enough, but to make it even more convenient, I added a BeetsPlugin.config
field, which is a Confit view into a subsection of the configuration named
after the plugin.

beets/plugins.py

@@ -1,5 +1,5 @@
 # This file is part of beets.
-# Copyright 2011, Adrian Sampson.
+# Copyright 2012, Adrian Sampson.
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -15,10 +15,10 @@
 """Support for beets plugins."""
 
 import logging
-import itertools
 import traceback
 from collections import defaultdict
 
+import beets
 from beets import mediafile
 
 PLUGIN_NAMESPACE = 'beetsplug'
@@ -37,12 +37,13 @@ class BeetsPlugin(object):
     functionality by defining a subclass of BeetsPlugin and overriding
     the abstract methods defined here.
     """
-    def __init__(self):
-        """Perform one-time plugin setup. There is probably no reason to
-        override this method.
+    def __init__(self, name=None):
+        """Perform one-time plugin setup.
         """
         _add_media_fields(self.item_fields())
         self.import_stages = []
+        self.name = name or self.__module__.split('.')[-1]
+        self.config = beets.config[self.name]
 
     def commands(self):
         """Should return a list of beets.ui.Subcommand objects for

beets/ui/commands.py

@@ -935,10 +935,7 @@ default_commands.append(stats_cmd)
 def show_version(lib, opts, args):
     print_('beets version %s' % beets.__version__)
     # Show plugins.
-    names = []
-    for plugin in plugins.find_plugins():
-        modname = plugin.__module__
-        names.append(modname.split('.')[-1])
+    names = [p.name for p in plugins.find_plugins()]
     if names:
         print_('plugins:', ', '.join(names))
     else:

beets/util/confit.py

@@ -139,6 +139,13 @@ class ConfigView(object):
 
         return value
 
+    def add(self, value):
+        """Add a value as a source for configuration data. The object as
+        added as the lowest-priority source. This can be used to
+        dynamically extend the defaults.
+        """
+        raise NotImplementedError
+
     def set(self, value):
         """Create an overlay source to set the value at this view.
         """
@@ -324,12 +331,6 @@ class RootView(ConfigView):
         self.name = ROOT_NAME
 
     def add(self, obj):
-        """Add the object (probably a dict) as a source for
-        configuration data. The object as added as the lowest-priority
-        source. This can be used to dynamically extend the defaults
-        (i.e., when loading a plugin that shares the main application's
-        config file).
-        """
         self.sources.append(obj)
 
     def set(self, value):
@@ -382,6 +383,9 @@ class Subview(ConfigView):
     def set(self, value):
         self.parent.set({self.key: value})
 
+    def add(self, value):
+        self.parent.add({self.key: value})
+
 
 # Config file paths, including platform-specific paths and in-package
 # defaults.

beetsplug/bpd/__init__.py

@@ -32,14 +32,6 @@ from beets import vfs
 from beets import config
 from beets.util import bluelet
 
-config.add({
-    'bpd': {
-        'host': u'',
-        'port': 6600,
-        'password': u'',
-    }
-})
-
 PROTOCOL_VERSION = '0.13.0'
 BUFSIZE = 1024
 
@@ -1129,6 +1121,14 @@ class BPDPlugin(BeetsPlugin):
     """Provides the "beet bpd" command for running a music player
     server.
     """
+    def __init__(self):
+        super(BPDPlugin, self).__init__()
+        self.config.add({
+            'host': u'',
+            'port': 6600,
+            'password': u'',
+        })
+
     def start_bpd(self, lib, host, port, password, debug):
         """Starts a BPD server."""
         if debug:
@@ -1149,11 +1149,11 @@ class BPDPlugin(BeetsPlugin):
             help='dump all MPD traffic to stdout')
 
         def func(lib, opts, args):
-            host = args.pop(0) if args else config['bpd']['host'].get(unicode)
-            port = args.pop(0) if args else config['bpd']['port'].get(int)
+            host = args.pop(0) if args else self.config['host'].get(unicode)
+            port = args.pop(0) if args else self.config['port'].get(int)
             if args:
                 raise beets.ui.UserError('too many arguments')
-            password = config['bpd']['password'].get(unicode)
+            password = self.config['password'].get(unicode)
             debug = opts.debug or False
             self.start_bpd(lib, host, int(port), password, debug)