jupyter · rgbkrk · Jan 13, 2017 · Dec 22, 2016 · Jan 3, 2017 · Jan 3, 2017
diff --git a/docs/source/public_server.rst b/docs/source/public_server.rst
@@ -53,6 +53,7 @@ configuring the :attr:`NotebookApp.password` setting in
 
 Prerequisite: A notebook configuration file
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
 Check to see if you have a notebook configuration file,
 :file:`jupyter_notebook_config.py`. The default location for this file
 is your Jupyter folder in your home directory, ``~/.jupyter``.
@@ -66,7 +67,20 @@ using the following command::
 
 Preparing a hashed password
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-You can prepare a hashed password using the function
+
+As of notebook version 5.0, you can enter and store a password for your
+notebook server with a single command.
+:command:`jupyter notebook password` will prompt you for your password
+and record the hashed password in your :file:`jupyter_notebook_config.json`.
+
+.. code-block:: bash
+
+    $ jupyter notebook password
+    Enter password:  ****
+    Verify password: ****
+    [NotebookPasswordApp] Wrote hashed password to /Users/you/.jupyter/jupyter_notebook_config.json
+
+You can prepare a hashed password manually, using the function
 :func:`notebook.auth.security.passwd`:
 
 .. code-block:: ipython

diff --git a/docs/source/security.rst b/docs/source/security.rst
@@ -58,8 +58,20 @@ Once you have visited this URL,
 a cookie will be set in your browser and you won't need to use the token again,
 unless you switch browsers, clear your cookies, or start a notebook server on a new port.
 
+Alternatives to token authentication
+------------------------------------
 
-You can disable authentication altogether by setting the token and password to empty strings,
+If a generated token doesn't work well for you,
+you can set a password for your notebook.
+:command:`jupyter notebook password` will prompt you for a password,
+and store the hashed password in your :file:`jupyter_notebook_config.json`.
+
+.. versionadded:: 5.0
+
+    :command:`jupyter notebook password` command is added.
+
+
+It is possible disable authentication altogether by setting the token and password to empty strings,
 but this is **NOT RECOMMENDED**, unless authentication or access restrictions are handled at a different layer in your web application:
 
 .. sourcecode:: python

diff --git a/notebook/auth/security.py b/notebook/auth/security.py
@@ -1,11 +1,20 @@
 """
 Password generation for the Notebook.
 """
+
+from contextlib import contextmanager
 import getpass
 import hashlib
+import io
+import json
+import os
 import random
+import traceback
+import warnings
 
-from ipython_genutils.py3compat import cast_bytes, str_to_bytes
+from ipython_genutils.py3compat import cast_bytes, str_to_bytes, cast_unicode
+from traitlets.config import Config, ConfigFileNotFound, JSONFileConfigLoader
+from jupyter_core.paths import jupyter_config_dir
 
 # Length of the salt in nr of hex chars, which implies salt_len * 4
 # bits of randomness.
@@ -99,3 +108,41 @@ def passwd_check(hashed_passphrase, passphrase):
     h.update(cast_bytes(passphrase, 'utf-8') + cast_bytes(salt, 'ascii'))
 
     return h.hexdigest() == pw_digest
+
+@contextmanager
+def persist_config(config_file=None, mode=0o600):
+    """Context manager that can be used to modify a config object
+
+    On exit of the context manager, the config will be written back to disk, 
+    by default with user-only (600) permissions.
+    """
+
+    if config_file is None:
+        config_file = os.path.join(jupyter_config_dir(), 'jupyter_notebook_config.json')
+
+    loader = JSONFileConfigLoader(os.path.basename(config_file), os.path.dirname(config_file))
+    try:
+        config = loader.load_config()
+    except ConfigFileNotFound:
+        config = Config()
+
+    yield config
+
+    with io.open(config_file, 'w', encoding='utf8') as f:
+        f.write(cast_unicode(json.dumps(config, indent=2)))
+
+    try:
+        os.chmod(config_file, mode)
+    except Exception as e:
+        tb = traceback.format_exc()
+        warnings.warn("Failed to set permissions on %s:\n%s" % (config_file, tb),
+            RuntimeWarning)
+
+
+def set_password(password=None, config_file=None):
+    """Ask user for password, store it in notebook json configuration file"""
+
+    hashed_password = passwd(password)
+
+    with persist_config(config_file) as config:
+        config.NotebookApp.password = hashed_password
diff --git a/notebook/notebookapp.py b/notebook/notebookapp.py
@@ -106,6 +106,7 @@
 _examples = """
 jupyter notebook                       # start the notebook
 jupyter notebook --certfile=mycert.pem # use SSL/TLS certificate
+jupyter notebook password              # enter a password to protect the server
 """
 
 DEV_NOTE_NPM = """It looks like you're running the notebook from source.
@@ -323,6 +324,24 @@ def init_handlers(self, settings):
         return new_handlers
 
 
+class NotebookPasswordApp(JupyterApp):
+    """Set a password for the notebook server.
+
+    Setting a password secures the notebook server
+    and removes the need for token-based authentication.
+    """
+
+    description = __doc__
+
+    def _config_file_default(self):
+        return os.path.join(self.config_dir, 'jupyter_notebook_config.json')
+
+    def start(self):
+        from .auth.security import set_password
+        set_password(config_file=self.config_file)
+        self.log.info("Wrote hashed password to %s" % self.config_file)
+
+
 class NbserverListApp(JupyterApp):
     version = __version__
     description="List currently running notebook servers."
@@ -426,6 +445,7 @@ class NotebookApp(JupyterApp):
 
     subcommands = dict(
         list=(NbserverListApp, NbserverListApp.description.splitlines()[0]),
+        password=(NotebookPasswordApp, NotebookPasswordApp.description.splitlines()[0]),
     )
 
     _log_formatter_cls = LogFormatter

diff --git a/notebook/tests/test_notebookapp.py b/notebook/tests/test_notebookapp.py
@@ -1,11 +1,18 @@
 """Test NotebookApp"""
 
-
+import getpass
 import logging
 import os
 import re
+from subprocess import Popen, PIPE, STDOUT
+import sys
 from tempfile import NamedTemporaryFile
 
+try:
+    from unittest.mock import patch
+except ImportError:
+    from mock import patch # py2
+
 import nose.tools as nt
 
 from traitlets.tests.utils import check_help_all_output
@@ -14,7 +21,7 @@
 from ipython_genutils.tempdir import TemporaryDirectory
 from traitlets import TraitError
 from notebook import notebookapp, __version__
-from notebook import notebookapp
+from notebook.auth.security import passwd_check
 NotebookApp = notebookapp.NotebookApp
 
 
@@ -117,3 +124,17 @@ def raise_on_bad_version(version):
 
 def test_current_version():
     raise_on_bad_version(__version__)
+
+def test_notebook_password():
+    password = 'secret'
+    with TemporaryDirectory() as td:
+        with patch.dict('os.environ', {
+            'JUPYTER_CONFIG_DIR': td,
+        }), patch.object(getpass, 'getpass', return_value=password):
+            app = notebookapp.NotebookPasswordApp(log_level=logging.ERROR)
+            app.initialize([])
+            app.start()
+            nb = NotebookApp()
+            nb.load_config_file()
+            nt.assert_not_equal(nb.password, '')
+            passwd_check(nb.password, password)