Merge pull request #2635 from pallets/feature/server-name-routing

Require opt-in for subdomain matching

CHANGES.rst

@@ -139,6 +139,10 @@ unreleased
   attribute on the session cookie. (`#2607`_)
 - Added :meth:`~flask.Flask.test_cli_runner` to create a Click runner
   that can invoke Flask CLI commands for testing. (`#2636`_)
+- Subdomain matching is disabled by default and setting
+  :data:`SERVER_NAME` does not implicily enable it. It can be enabled by
+  passing ``subdomain_matching=True`` to the ``Flask`` constructor.
+  (`#2635`_)
 
 .. _pallets/meta#24: https://github.com/pallets/meta/issues/24
 .. _#1421: https://github.com/pallets/flask/issues/1421
@@ -181,6 +185,7 @@ unreleased
 .. _#2606: https://github.com/pallets/flask/pull/2606
 .. _#2607: https://github.com/pallets/flask/pull/2607
 .. _#2636: https://github.com/pallets/flask/pull/2636
+.. _#2635: https://github.com/pallets/flask/pull/2635
 
 
 Version 0.12.2

docs/config.rst

@@ -181,8 +181,8 @@ The following configuration values are used internally by Flask:
 .. py:data:: SESSION_COOKIE_DOMAIN
 
     The domain match rule that the session cookie will be valid for. If not
-    set, the cookie will be valid for all subdomains of ``SERVER_NAME``. If
-    ``False``, the cookie's domain will not be set.
+    set, the cookie will be valid for all subdomains of :data:`SERVER_NAME`.
+    If ``False``, the cookie's domain will not be set.
 
     Default: ``None``
 
@@ -257,13 +257,14 @@ The following configuration values are used internally by Flask:
 
 .. py:data:: SERVER_NAME
 
-    Inform the application what host and port it is bound to. Required for
-    subdomain route matching support.
+    Inform the application what host and port it is bound to. Required
+    for subdomain route matching support.
 
     If set, will be used for the session cookie domain if
-    ``SESSION_COOKIE_DOMAIN`` is not set. Modern web browsers will not allow
-    setting cookies for domains without a dot. To use a domain locally,
-    add any names that should route to the app to your ``hosts`` file. ::
+    :data:`SESSION_COOKIE_DOMAIN` is not set. Modern web browsers will
+    not allow setting cookies for domains without a dot. To use a domain
+    locally, add any names that should route to the app to your
+    ``hosts`` file. ::
 
         127.0.0.1 localhost.dev
 

flask/app.py

@@ -123,8 +123,13 @@ class Flask(_PackageBoundObject):
     .. versionadded:: 0.11
        The `root_path` parameter was added.
 
-    .. versionadded:: 0.13
-       The `host_matching` and `static_host` parameters were added.
+    .. versionadded:: 1.0
+       The ``host_matching`` and ``static_host`` parameters were added.
+
+    .. versionadded:: 1.0
+       The ``subdomain_matching`` parameter was added. Subdomain
+       matching needs to be enabled manually now. Setting
+       :data:`SERVER_NAME` does not implicitly enable it.
 
     :param import_name: the name of the application package
     :param static_url_path: can be used to specify a different path for the
@@ -133,11 +138,13 @@ class Flask(_PackageBoundObject):
     :param static_folder: the folder with static files that should be served
                           at `static_url_path`.  Defaults to the ``'static'``
                           folder in the root path of the application.
-    :param host_matching: sets the app's ``url_map.host_matching`` to the given
-                          value. Defaults to False.
-    :param static_host: the host to use when adding the static route. Defaults
-                        to None. Required when using ``host_matching=True``
+    :param static_host: the host to use when adding the static route.
+        Defaults to None. Required when using ``host_matching=True``
         with a ``static_folder`` configured.
+    :param host_matching: set ``url_map.host_matching`` attribute.
+        Defaults to False.
+    :param subdomain_matching: consider the subdomain relative to
+        :data:`SERVER_NAME` when matching routes. Defaults to False.
     :param template_folder: the folder that contains the templates that should
                             be used by the application.  Defaults to
                             ``'templates'`` folder in the root path of the
@@ -347,6 +354,7 @@ class Flask(_PackageBoundObject):
         static_folder='static',
         static_host=None,
         host_matching=False,
+        subdomain_matching=False,
         template_folder='templates',
         instance_path=None,
         instance_relative_config=False,
@@ -530,6 +538,7 @@ class Flask(_PackageBoundObject):
         self.url_map = Map()
 
         self.url_map.host_matching = host_matching
+        self.subdomain_matching = subdomain_matching
 
         # tracks internally if the application already handled at least one
         # request.
@@ -1978,18 +1987,29 @@ class Flask(_PackageBoundObject):
 
     def create_url_adapter(self, request):
         """Creates a URL adapter for the given request. The URL adapter
-        is created at a point where the request context is not yet set up
-        so the request is passed explicitly.
+        is created at a point where the request context is not yet set
+        up so the request is passed explicitly.
 
         .. versionadded:: 0.6
 
         .. versionchanged:: 0.9
            This can now also be called without a request object when the
            URL adapter is created for the application context.
+
+        .. versionchanged:: 1.0
+            :data:`SERVER_NAME` no longer implicitly enables subdomain
+            matching. Use :attr:`subdomain_matching` instead.
         """
         if request is not None:
-            return self.url_map.bind_to_environ(request.environ,
-                server_name=self.config['SERVER_NAME'])
+            # If subdomain matching is disabled (the default), use the
+            # default subdomain in all cases. This should be the default
+            # in Werkzeug but it currently does not have that feature.
+            subdomain = ((self.url_map.default_subdomain or None)
+                         if not self.subdomain_matching else None)
+            return self.url_map.bind_to_environ(
+                request.environ,
+                server_name=self.config['SERVER_NAME'],
+                subdomain=subdomain)
         # We need at the very least the server name to be set for this
         # to work.
         if self.config['SERVER_NAME'] is not None:

tests/test_basic.py

@@ -1429,10 +1429,12 @@ def test_request_locals():
     assert not flask.g
 
 
-def test_test_app_proper_environ(app, client):
+def test_test_app_proper_environ():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config.update(
         SERVER_NAME='localhost.localdomain:5000'
     )
+    client = app.test_client()
 
     @app.route('/')
     def index():
@@ -1783,8 +1785,10 @@ def test_g_iteration_protocol(app_ctx):
     assert sorted(flask.g) == ['bar', 'foo']
 
 
-def test_subdomain_basic_support(app, client):
+def test_subdomain_basic_support():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config['SERVER_NAME'] = 'localhost.localdomain'
+    client = app.test_client()
 
     @app.route('/')
     def normal_index():
@@ -1801,7 +1805,9 @@ def test_subdomain_basic_support(app, client):
     assert rv.data == b'test index'
 
 
-def test_subdomain_matching(app, client):
+def test_subdomain_matching():
+    app = flask.Flask(__name__, subdomain_matching=True)
+    client = app.test_client()
     app.config['SERVER_NAME'] = 'localhost.localdomain'
 
     @app.route('/', subdomain='<user>')
@@ -1812,8 +1818,10 @@ def test_subdomain_matching(app, client):
     assert rv.data == b'index for mitsuhiko'
 
 
-def test_subdomain_matching_with_ports(app, client):
+def test_subdomain_matching_with_ports():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config['SERVER_NAME'] = 'localhost.localdomain:3000'
+    client = app.test_client()
 
     @app.route('/', subdomain='<user>')
     def index(user):
@@ -1823,6 +1831,25 @@ def test_subdomain_matching_with_ports(app, client):
     assert rv.data == b'index for mitsuhiko'
 
 
+@pytest.mark.parametrize('matching', (False, True))
+def test_subdomain_matching_other_name(matching):
+    app = flask.Flask(__name__, subdomain_matching=matching)
+    app.config['SERVER_NAME'] = 'localhost.localdomain:3000'
+    client = app.test_client()
+
+    @app.route('/')
+    def index():
+        return '', 204
+
+    # ip address can't match name
+    rv = client.get('/', 'http://127.0.0.1:3000/')
+    assert rv.status_code == 404 if matching else 204
+
+    # allow all subdomains if matching is disabled
+    rv = client.get('/', 'http://www.localhost.localdomain:3000/')
+    assert rv.status_code == 404 if matching else 204
+
+
 def test_multi_route_rules(app, client):
     @app.route('/')
     @app.route('/<test>/')

tests/test_testing.py

@@ -114,9 +114,11 @@ def test_path_is_url(app):
     assert eb.path == '/'
 
 
-def test_blueprint_with_subdomain(app, client):
+def test_blueprint_with_subdomain():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config['SERVER_NAME'] = 'example.com:1234'
     app.config['APPLICATION_ROOT'] = '/foo'
+    client = app.test_client()
 
     bp = flask.Blueprint('company', __name__, subdomain='xxx')
 
@@ -304,8 +306,10 @@ def test_json_request_and_response(app, client):
         assert rv.get_json() == json_data
 
 
-def test_subdomain(app, client):
+def test_subdomain():
+    app = flask.Flask(__name__, subdomain_matching=True)
     app.config['SERVER_NAME'] = 'example.com'
+    client = app.test_client()
 
     @app.route('/', subdomain='<company_id>')
     def view(company_id):