use traitlets-4.1 observe/default decorators

jupyterhub/app.py

@@ -36,6 +36,7 @@ from tornado import gen, web
 from traitlets import (
     Unicode, Integer, Dict, TraitError, List, Bool, Any,
     Type, Set, Instance, Bytes, Float,
+    observe, default,
 )
 from traitlets.config import Application, catch_config_error
 
@@ -209,6 +210,7 @@ class JupyterHub(Application):
         help="Paths to search for jinja templates.",
     ).tag(config=True)
 
+    @default('template_paths')
     def _template_paths_default(self):
         return [os.path.join(self.data_files_path, 'templates')]
     
@@ -262,6 +264,8 @@ class JupyterHub(Application):
     logo_file = Unicode('',
         help="Specify path to a logo image to override the Jupyter logo in the banner."
     ).tag(config=True)
+
+    @default('logo_file')
     def _logo_file_default(self):
         return os.path.join(self.data_files_path, 'static', 'images', 'jupyter.png')
     
@@ -284,6 +288,8 @@ class JupyterHub(Application):
         Loaded from the CONFIGPROXY_AUTH_TOKEN env variable by default.
         """
     ).tag(config=True)
+    
+    @default('proxy_auth_token')
     def _proxy_auth_token_default(self):
         token = os.environ.get('CONFIGPROXY_AUTH_TOKEN', None)
         if not token:
@@ -302,6 +308,8 @@ class JupyterHub(Application):
     proxy_api_port = Integer(
         help="The port for the proxy API handlers"
     ).tag(config=True)
+    
+    @default('proxy_api_port')
     def _proxy_api_port_default(self):
         return self.port + 1
     
@@ -314,21 +322,27 @@ class JupyterHub(Application):
     hub_prefix = URLPrefix('/hub/',
         help="The prefix for the hub server. Must not be '/'"
     ).tag(config=True)
+    
+    @default('hub_prefix')
     def _hub_prefix_default(self):
         return url_path_join(self.base_url, '/hub/')
     
+    @observe('hub_prefix')
     def _hub_prefix_changed(self, name, old, new):
         if new == '/':
             raise TraitError("'/' is not a valid hub prefix")
         if not new.startswith(self.base_url):
             self.hub_prefix = url_path_join(self.base_url, new)
     
-    cookie_secret = Bytes(env='JPY_COOKIE_SECRET',
+    cookie_secret = Bytes(
         help="""The cookie secret to use to encrypt cookies.
 
         Loaded from the JPY_COOKIE_SECRET env variable by default.
         """
-    ).tag(config=True)
+    ).tag(
+        config=True,
+        env='JPY_COOKIE_SECRET',
+    )
     
     cookie_secret_file = Unicode('jupyterhub_cookie_secret',
         help="""File in which to store the cookie secret."""
@@ -350,6 +364,8 @@ class JupyterHub(Application):
     ).tag(config=True)
     
     authenticator = Instance(Authenticator)
+
+    @default('authenticator')
     def _authenticator_default(self):
         return self.authenticator_class(parent=self, db=self.db)
 
@@ -364,7 +380,10 @@ class JupyterHub(Application):
     db_url = Unicode('sqlite:///jupyterhub.sqlite',
         help="url for the database. e.g. `sqlite:///jupyterhub.sqlite`"
     ).tag(config=True)
-    def _db_url_changed(self, name, old, new):
+
+    @observe('db_url')
+    def _db_url_changed(self, change):
+        new = change['new']
         if '://' not in new:
             # assume sqlite, if given as a plain filename
             self.db_url = 'sqlite:///%s' % new
@@ -384,6 +403,8 @@ class JupyterHub(Application):
     session_factory = Any()
     
     users = Instance(UserDict)
+    
+    @default('users')
     def _users_default(self):
         assert self.tornado_settings
         return UserDict(db_factory=lambda : self.db, settings=self.tornado_settings)
@@ -435,13 +456,16 @@ class JupyterHub(Application):
     proxy_process = None
     io_loop = None
     
+    @default('log_level')
     def _log_level_default(self):
         return logging.INFO
     
+    @default('log_datefmt')
     def _log_datefmt_default(self):
         """Exclude date from default date format"""
         return "%Y-%m-%d %H:%M:%S"
 
+    @default('log_format')
     def _log_format_default(self):
         """override default log format to include time"""
         return "%(color)s[%(levelname)1.1s %(asctime)s.%(msecs).03d %(name)s %(module)s:%(lineno)d]%(end_color)s %(message)s"
@@ -537,7 +561,7 @@ class JupyterHub(Application):
     def init_secrets(self):
         trait_name = 'cookie_secret'
         trait = self.traits()[trait_name]
-        env_name = trait.get_metadata('env')
+        env_name = trait.metadata.get('env')
         secret_file = os.path.abspath(
             os.path.expanduser(self.cookie_secret_file)
         )

jupyterhub/auth.py

@@ -15,7 +15,7 @@ from tornado import gen
 import pamela
 
 from traitlets.config import LoggingConfigurable
-from traitlets import Bool, Set, Unicode, Dict, Any
+from traitlets import Bool, Set, Unicode, Dict, Any, default, observe
 
 from .handlers.login import LoginHandler
 from .utils import url_path_join
@@ -61,10 +61,11 @@ class Authenticator(LoggingConfigurable):
         If not defined: allow any username.
         """
     ).tag(config=True)
-    def _username_pattern_changed(self, name, old, new):
-        if not new:
+    @observe('username_pattern')
+    def _username_pattern_changed(self, change):
+        if not change['new']:
             self.username_regex = None
-        self.username_regex = re.compile(new)
+        self.username_regex = re.compile(change['new'])
     
     username_regex = Any()
     
@@ -272,6 +273,8 @@ class LocalAuthenticator(Authenticator):
         when the user 'river' is created.
         """
     ).tag(config=True)
+    
+    @default('add_user_cmd')
     def _add_user_cmd_default(self):
         if sys.platform == 'darwin':
             raise ValueError("I don't know how to create users on OS X")
@@ -285,10 +288,10 @@ class LocalAuthenticator(Authenticator):
     group_whitelist = Set(
         help="Automatically whitelist anyone in this group.",
     ).tag(config=True)
-
-    def _group_whitelist_changed(self, name, old, new):
+    @observe('group_whitelist')
+    def _group_whitelist_changed(self, change):
         if self.whitelist:
-            self.log.warn(
+            self.log.warning(
                 "Ignoring username whitelist because group whitelist supplied!"
             )
 

jupyterhub/spawner.py

@@ -128,7 +128,7 @@ class Spawner(LoggingConfigurable):
     cmd = Command(['jupyterhub-singleuser'],
         help="""The command used for starting notebooks."""
     ).tag(config=True)
-    args = List(Unicode,
+    args = List(Unicode(),
         help="""Extra arguments to be passed to the single-user server"""
     ).tag(config=True)
     

jupyterhub/tests/mocking.py

@@ -13,6 +13,8 @@ from tornado import gen
 from tornado.concurrent import Future
 from tornado.ioloop import IOLoop
 
+from traitlets import default
+
 from ..app import JupyterHub
 from ..auth import PAMAuthenticator
 from .. import orm
@@ -44,7 +46,7 @@ class MockSpawner(LocalProcessSpawner):
     
     def user_env(self, env):
         return env
-    
+    @default('cmd')
     def _cmd_default(self):
         return [sys.executable, '-m', 'jupyterhub.tests.mocksu']
 
@@ -66,6 +68,7 @@ class SlowSpawner(MockSpawner):
 class NeverSpawner(MockSpawner):
     """A spawner that will never start"""
     
+    @default('start_timeout')
     def _start_timeout_default(self):
         return 1
     
@@ -90,6 +93,7 @@ class FormSpawner(MockSpawner):
 
 
 class MockPAMAuthenticator(PAMAuthenticator):
+    @default('admin_users')
     def _admin_users_default(self):
         return {'admin'}
     
@@ -113,15 +117,19 @@ class MockHub(JupyterHub):
     
     last_activity_interval = 2
     
+    @default('subdomain_host')
     def _subdomain_host_default(self):
         return os.environ.get('JUPYTERHUB_TEST_SUBDOMAIN_HOST', '')
     
+    @default('ip')
     def _ip_default(self):
         return '127.0.0.1'
     
+    @default('authenticator_class')
     def _authenticator_class_default(self):
         return MockPAMAuthenticator
     
+    @default('spawner_class')
     def _spawner_class_default(self):
         return MockSpawner
     

jupyterhub/traitlets.py

@@ -21,7 +21,7 @@ class Command(List):
         kwargs.setdefault('minlen', 1)
         if isinstance(default_value, str):
             default_value = [default_value]
-        super().__init__(Unicode, default_value, **kwargs)
+        super().__init__(Unicode(), default_value, **kwargs)
         
     def validate(self, obj, value):
         if isinstance(value, str):

jupyterhub/user.py

@@ -12,7 +12,7 @@ from sqlalchemy import inspect
 from .utils import url_path_join
 
 from . import orm
-from traitlets import HasTraits, Any, Dict
+from traitlets import HasTraits, Any, Dict, observe, default
 from .spawner import LocalProcessSpawner
 
 
@@ -41,7 +41,7 @@ class UserDict(dict):
         elif isinstance(key, str):
             orm_user = self.db.query(orm.User).filter(orm.User.name==key).first()
             if orm_user is None:
-                raise KeyError("No such user: %s" % name)
+                raise KeyError("No such user: %s" % key)
             else:
                 key = orm_user
         if isinstance(key, orm.User):
@@ -75,22 +75,24 @@ class UserDict(dict):
 
 class User(HasTraits):
     
+    @default('log')
     def _log_default(self):
         return app_log
     
     settings = Dict()
     
     db = Any(allow_none=True)
+    @default('db')
     def _db_default(self):
         if self.orm_user:
             return inspect(self.orm_user).session
-    
-    def _db_changed(self, name, old, new):
+    @observe('db')
+    def _db_changed(self, change):
         """Changing db session reacquires ORM User object"""
         # db session changed, re-get orm User
         if self.orm_user:
             id = self.orm_user.id
-            self.orm_user = new.query(orm.User).filter(orm.User.id==id).first()
+            self.orm_user = change['new'].query(orm.User).filter(orm.User.id==id).first()
         self.spawner.db = self.db
     
     orm_user = None