Support yaml config file

pyls/__main__.py

@@ -4,6 +4,7 @@
 import logging
 import logging.config
 import sys
+import yaml
 from .python_ls import start_io_lang_server, start_tcp_lang_server, PythonLanguageServer
 
 LOG_FORMAT = "%(asctime)s UTC - %(levelname)s - %(name)s - %(message)s"
@@ -30,6 +31,10 @@ def add_arguments(parser):
         "and auto shut down language server process when parent process is not alive."
         "Note that this may not work on a Windows machine."
     )
+    parser.add_argument(
+        '-c', '--conf',
+        help='Pass a YAML file containing PYLS settings'
+    )
 
     log_group = parser.add_mutually_exclusive_group()
     log_group.add_argument(
@@ -54,6 +59,10 @@ def main():
     args = parser.parse_args()
     _configure_logger(args.verbose, args.log_config, args.log_file)
 
+    if args.conf:
+        with open(args.conf, 'r') as f:
+            PythonLanguageServer.INITIAL_CONFIG = yaml.load(f)
+
     if args.tcp:
         start_tcp_lang_server(args.host, args.port, PythonLanguageServer)
     else:

pyls/python_ls.py

@@ -65,9 +65,10 @@ class PythonLanguageServer(MethodDispatcher):
     """ Implementation of the Microsoft VSCode Language Server Protocol
     https://github.com/Microsoft/language-server-protocol/blob/master/versions/protocol-1-x.md
     """
-
     # pylint: disable=too-many-public-methods,redefined-builtin
 
+    INITIAL_CONFIG = {}
+
     def __init__(self, rx, tx, check_parent_process=False):
         self.workspace = None
         self.config = None
@@ -154,6 +155,7 @@ def m_initialize(self, processId=None, rootUri=None, rootPath=None, initializati
 
         self.workspace = Workspace(rootUri, self._endpoint)
         self.config = config.Config(rootUri, initializationOptions or {}, processId)
+        self.config.update(PythonLanguageServer.INITIAL_CONFIG)
         self._dispatchers = self._hook('pyls_dispatchers')
         self._hook('pyls_initialize')
 

setup.py

@@ -37,7 +37,8 @@
         'futures; python_version<"3.2"',
         'jedi>=0.13.2',
         'python-jsonrpc-server>=0.1.0',
-        'pluggy'
+        'pluggy',
+        'pyyaml'
     ],
 
     # List additional groups of dependencies here (e.g. development