Better handling of config files using python ConfigParser

Closes #4

README.md

@@ -31,17 +31,19 @@ or as a WSGI application (on Apache for instance). But first:
 
 ### Configuration
 
-Supysonic looks for two files for its configuration: `~/.supysonic` or `/etc/supysonic` (in this order).
-Options are set using the `KEY = VALUE` syntax. String values must be quote-enclosed.
+Supysonic looks for two files for its configuration: `/etc/supysonic` and `~/.supysonic`, merging values from the two files.
+Configuration files must respect a structure similar to Windows INI file, with `[section]` headers and using a `KEY = VALUE`
+or `KEY: VALUE` syntax.
 
 Available settings are:
-* **DATABASE_URI**: a SQLAlchemy [database URI](http://docs.sqlalchemy.org/en/rel_0_8/core/engines.html#database-urls).
-  I personnaly use SQLite (`sqlite:////var/supysonic/supysonic.db`), but it might not be the brightest
-  idea for large libraries.
-* **CACHE_DIR**: path to a cache folder. Mostly used for resized cover art images.
-* **LOG_FILE**: path and base name of a rolling log file.
-* **LASTFM_KEY**: Last.FM [API key](http://www.last.fm/api/accounts) to enable scrobbling
-* **LASTFM_SECRET**: Last.FM API secret matching the key.
+* Section **base**:
+  * **database_uri**: required, a SQLAlchemy [database URI](http://docs.sqlalchemy.org/en/rel_0_8/core/engines.html#database-urls).
+    I personnaly use SQLite (`sqlite:////var/supysonic/supysonic.db`), but it might not be the brightest idea for large libraries.
+  * **cache_dir**: path to a cache folder. Mostly used for resized cover art images. Defaults to `<system temp dir>/supysonic`.
+  * **log_file**: path and base name of a rolling log file.
+* Section **lastfm**:
+  * **api_key**: Last.FM [API key](http://www.last.fm/api/accounts) to enable scrobbling
+  * **secret**: Last.FM API secret matching the key.
 
 ### Running as a standalone server
 

api/media.py

@@ -72,7 +72,7 @@ def cover_art():
 	if size > im.size[0] and size > im.size[1]:
 		return send_file(os.path.join(res.path, 'cover.jpg'))
 
-	size_path = os.path.join(config.get('CACHE_DIR'), str(size))
+	size_path = os.path.join(config.get('base', 'cache_dir'), str(size))
 	path = os.path.join(size_path, str(res.id))
 	if os.path.exists(path):
 		return send_file(path)

config.py

@@ -1,23 +1,31 @@
 # coding: utf-8
 
-import os
+import os, sys, tempfile, ConfigParser
+
+config = ConfigParser.RawConfigParser({ 'cache_dir': os.path.join(tempfile.gettempdir(), 'supysonic') })
 
 def check():
-	path = os.path.join(os.path.expanduser('~'), '.supysonic')
-	if os.path.exists(path):
-		return path
-	path = '/etc/supysonic'
-	if os.path.exists(path):
-		return path
+	try:
+		ret = config.read([ '/etc/supysonic', os.path.expanduser('~/.supysonic') ])
+	except (ConfigParser.MissingSectionHeaderError, ConfigParser.ParsingError), e:
+		print >>sys.stderr, "Error while parsing the configuration file(s):\n%s" % str(e)
 		return False
 
-config_path = check()
-config_dict = {}
-if config_path:
-	with open(config_path) as f:
-		for line in f:
-			spl = line.split('=')
-			config_dict[spl[0].strip()] = eval(spl[1])
+	if not ret:
+		print >>sys.stderr, "No configuration file found"
+		return False
+
+	try:
+		config.get('base', 'database_uri')
+	except:
+		print >>sys.stderr, "No database URI set"
+		return False
+
+	return True
+
+def get(section, name):
+	try:
+		return config.get(section, name)
+	except:
+		return None
 
-def get(name):
-	return config_dict.get(name)

db.py

@@ -42,7 +42,7 @@ class UUID(TypeDecorator):
 def now():
 	return datetime.datetime.now().replace(microsecond = 0)
 
-engine = create_engine(config.get('DATABASE_URI'), convert_unicode = True)
+engine = create_engine(config.get('base', 'database_uri'), convert_unicode = True)
 session = scoped_session(sessionmaker(autocommit = False, autoflush = False, bind = engine))
 
 Base = declarative_base()

lastfm.py

@@ -7,9 +7,9 @@ from db import session
 class LastFm:
 	def __init__(self, user, logger):
 		self.__user = user
-		self.__api_key = config.get('LASTFM_KEY')
-		self.__api_secret = config.get('LASTFM_SECRET')
-		self.__enabled = self.__api_key is not None
+		self.__api_key = config.get('lastfm', 'api_key')
+		self.__api_secret = config.get('lastfm', 'secret')
+		self.__enabled = self.__api_key is not None and self.__api_secret is not None
 		self.__logger = logger
 
 	def link_account(self, token):

main.py

@@ -5,11 +5,10 @@ import os.path, sys
 
 if __name__ == '__main__':
 	if not config.check():
-		print >>sys.stderr, "Couldn't find configuration file"
 		sys.exit(1)
 
-	if not os.path.exists(config.get('CACHE_DIR')):
-		os.makedirs(config.get('CACHE_DIR'))
+	if not os.path.exists(config.get('base', 'cache_dir')):
+		os.makedirs(config.get('base', 'cache_dir'))
 
 	import db
 	from web import app

main.wsgi

@@ -7,8 +7,8 @@ import config
 if not config.check():
 	sys.exit(1)
 
-if not os.path.exists(config.get('CACHE_DIR')):
-	os.makedirs(config.get('CACHE_DIR'))
+if not os.path.exists(config.get('base', 'cache_dir')):
+	os.makedirs(config.get('base', 'cache_dir'))
 
 import db
 db.init_db()

user.py

@@ -26,7 +26,7 @@ def user_index():
 
 @app.route('/user/me')
 def user_profile():
-	return render_template('profile.html', user = UserManager.get(session.get('userid'))[1], api_key = config.get('LASTFM_KEY'))
+	return render_template('profile.html', user = UserManager.get(session.get('userid'))[1], api_key = config.get('lastfm', 'api_key'))
 
 @app.route('/user/changemail', methods = [ 'GET', 'POST' ])
 def change_mail():

web.py

@@ -6,10 +6,10 @@ app = Flask(__name__)
 app.secret_key = '?9huDM\\H'
 
 import config
-if config.get('LOG_FILE'):
+if config.get('base', 'log_file'):
 	import logging
 	from logging.handlers import TimedRotatingFileHandler
-	handler = TimedRotatingFileHandler(config.get('LOG_FILE'), when = 'midnight')
+	handler = TimedRotatingFileHandler(config.get('base', 'log_file'), when = 'midnight')
 	handler.setLevel(logging.WARNING)
 	app.logger.addHandler(handler)