Implement OPTIONS verb for storage nodes.

Many times new deployers get mysterious errors after first setting up their
Swift clusters. Most of the time, the errors are because the values in the ring
are incorrect (e.g. a bad port number). OPTIONS will be used in a ring checker
(which is WIP) that validates values in the ring.

This patch includes OPTIONS for storage nodes and respective tests.

Change-Id: Ia0033756d070bef11d921180e8d32a1ab2b88acf

swift/account/server.py

@@ -32,6 +32,7 @@
 from swift.common.constraints import check_mount, valid_timestamp, check_utf8
 from swift.common import constraints
 from swift.common.db_replicator import ReplicatorRpc
+from swift.common.base_storage_server import BaseStorageServer
 from swift.common.swob import HTTPAccepted, HTTPBadRequest, \
     HTTPCreated, HTTPForbidden, HTTPInternalServerError, \
     HTTPMethodNotAllowed, HTTPNoContent, HTTPNotFound, \
@@ -40,18 +41,15 @@
 from swift.common.request_helpers import is_sys_or_user_meta
 
 
-class AccountController(object):
+class AccountController(BaseStorageServer):
     """WSGI controller for the account server."""
 
     def __init__(self, conf, logger=None):
+        super(AccountController, self).__init__(conf)
         self.logger = logger or get_logger(conf, log_route='account-server')
         self.log_requests = config_true_value(conf.get('log_requests', 'true'))
         self.root = conf.get('devices', '/srv/node')
         self.mount_check = config_true_value(conf.get('mount_check', 'true'))
-        replication_server = conf.get('replication_server', None)
-        if replication_server is not None:
-            replication_server = config_true_value(replication_server)
-        self.replication_server = replication_server
         self.replicator_rpc = ReplicatorRpc(self.root, DATADIR, AccountBroker,
                                             self.mount_check,
                                             logger=self.logger)
@@ -262,15 +260,12 @@ def __call__(self, env, start_response):
             try:
                 # disallow methods which are not publicly accessible
                 try:
-                    method = getattr(self, req.method)
-                    getattr(method, 'publicly_accessible')
-                    replication_method = getattr(method, 'replication', False)
-                    if (self.replication_server is not None and
-                            self.replication_server != replication_method):
+                    if req.method not in self.allowed_methods:
                         raise AttributeError('Not allowed method.')
                 except AttributeError:
                     res = HTTPMethodNotAllowed()
                 else:
+                    method = getattr(self, req.method)
                     res = method(req)
             except HTTPException as error_response:
                 res = error_response

swift/common/base_storage_server.py

@@ -0,0 +1,70 @@
+# Copyright (c) 2010-2014 OpenStack Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import inspect
+from swift.common.utils import public, timing_stats, config_true_value
+from swift.common.swob import Response
+
+
+class BaseStorageServer(object):
+    """
+    Implements common OPTIONS method for object, account, container servers.
+    """
+
+    def __init__(self, conf, **kwargs):
+        self._allowed_methods = None
+        replication_server = conf.get('replication_server', None)
+        if replication_server is not None:
+            replication_server = config_true_value(replication_server)
+        self.replication_server = replication_server
+
+    @property
+    def allowed_methods(self):
+        if self._allowed_methods is None:
+            self._allowed_methods = []
+            all_methods = inspect.getmembers(self, predicate=callable)
+
+            if self.replication_server is True:
+                for name, m in all_methods:
+                    if (getattr(m, 'publicly_accessible', False) and
+                            getattr(m, 'replication', False)):
+                        self._allowed_methods.append(name)
+            elif self.replication_server is False:
+                for name, m in all_methods:
+                    if (getattr(m, 'publicly_accessible', False) and not
+                            getattr(m, 'replication', False)):
+                        self._allowed_methods.append(name)
+            elif self.replication_server is None:
+                for name, m in all_methods:
+                    if getattr(m, 'publicly_accessible', False):
+                        self._allowed_methods.append(name)
+
+            self._allowed_methods.sort()
+        return self._allowed_methods
+
+    @public
+    @timing_stats()
+    def OPTIONS(self, req):
+        """
+        Base handler for OPTIONS requests
+
+        :param req: swob.Request object
+        :returns: swob.Response object
+        """
+        # Prepare the default response
+        headers = {'Allow': ', '.join(self.allowed_methods)}
+        resp = Response(status=200, request=req, headers=headers)
+
+        return resp

swift/container/server.py

@@ -38,6 +38,7 @@
 from swift.common.exceptions import ConnectionTimeout
 from swift.common.http import HTTP_NOT_FOUND, is_success
 from swift.common.storage_policy import POLICIES
+from swift.common.base_storage_server import BaseStorageServer
 from swift.common.swob import HTTPAccepted, HTTPBadRequest, HTTPConflict, \
     HTTPCreated, HTTPInternalServerError, HTTPNoContent, HTTPNotFound, \
     HTTPPreconditionFailed, HTTPMethodNotAllowed, Request, Response, \
@@ -71,24 +72,21 @@ def gen_resp_headers(info, is_deleted=False):
     return headers
 
 
-class ContainerController(object):
+class ContainerController(BaseStorageServer):
     """WSGI Controller for the container server."""
 
     # Ensure these are all lowercase
     save_headers = ['x-container-read', 'x-container-write',
                     'x-container-sync-key', 'x-container-sync-to']
 
     def __init__(self, conf, logger=None):
+        super(ContainerController, self).__init__(conf)
         self.logger = logger or get_logger(conf, log_route='container-server')
         self.log_requests = config_true_value(conf.get('log_requests', 'true'))
         self.root = conf.get('devices', '/srv/node')
         self.mount_check = config_true_value(conf.get('mount_check', 'true'))
         self.node_timeout = int(conf.get('node_timeout', 3))
         self.conn_timeout = float(conf.get('conn_timeout', 0.5))
-        replication_server = conf.get('replication_server', None)
-        if replication_server is not None:
-            replication_server = config_true_value(replication_server)
-        self.replication_server = replication_server
         #: ContainerSyncCluster instance for validating sync-to values.
         self.realms_conf = ContainerSyncRealms(
             os.path.join(
@@ -564,15 +562,12 @@ def __call__(self, env, start_response):
             try:
                 # disallow methods which have not been marked 'public'
                 try:
-                    method = getattr(self, req.method)
-                    getattr(method, 'publicly_accessible')
-                    replication_method = getattr(method, 'replication', False)
-                    if (self.replication_server is not None and
-                            self.replication_server != replication_method):
+                    if req.method not in self.allowed_methods:
                         raise AttributeError('Not allowed method.')
                 except AttributeError:
                     res = HTTPMethodNotAllowed()
                 else:
+                    method = getattr(self, req.method)
                     res = method(req)
             except HTTPException as error_response:
                 res = error_response

swift/obj/server.py

@@ -40,6 +40,7 @@
     DiskFileXattrNotSupported
 from swift.obj import ssync_receiver
 from swift.common.http import is_success
+from swift.common.base_storage_server import BaseStorageServer
 from swift.common.request_helpers import get_name_and_placement, \
     is_user_meta, is_sys_or_user_meta
 from swift.common.swob import HTTPAccepted, HTTPBadRequest, HTTPCreated, \
@@ -64,7 +65,7 @@ def __len__(self):
         return wsgi.MINIMUM_CHUNK_SIZE + 1
 
 
-class ObjectController(object):
+class ObjectController(BaseStorageServer):
     """Implements the WSGI application for the Swift Object Server."""
 
     def __init__(self, conf, logger=None):
@@ -74,6 +75,7 @@ def __init__(self, conf, logger=None):
         <source-dir>/etc/object-server.conf-sample or
         /etc/swift/object-server.conf-sample.
         """
+        super(ObjectController, self).__init__(conf)
         self.logger = logger or get_logger(conf, log_route='object-server')
         self.node_timeout = int(conf.get('node_timeout', 3))
         self.conn_timeout = float(conf.get('conn_timeout', 0.5))
@@ -85,10 +87,6 @@ def __init__(self, conf, logger=None):
         self.slow = int(conf.get('slow', 0))
         self.keep_cache_private = \
             config_true_value(conf.get('keep_cache_private', 'false'))
-        replication_server = conf.get('replication_server', None)
-        if replication_server is not None:
-            replication_server = config_true_value(replication_server)
-        self.replication_server = replication_server
 
         default_allowed_headers = '''
             content-disposition,
@@ -708,15 +706,12 @@ def __call__(self, env, start_response):
             try:
                 # disallow methods which have not been marked 'public'
                 try:
-                    method = getattr(self, req.method)
-                    getattr(method, 'publicly_accessible')
-                    replication_method = getattr(method, 'replication', False)
-                    if (self.replication_server is not None and
-                            self.replication_server != replication_method):
+                    if req.method not in self.allowed_methods:
                         raise AttributeError('Not allowed method.')
                 except AttributeError:
                     res = HTTPMethodNotAllowed()
                 else:
+                    method = getattr(self, req.method)
                     res = method(req)
             except DiskFileCollision:
                 res = HTTPForbidden(request=req)

test/unit/account/test_server.py

@@ -55,6 +55,18 @@ def tearDown(self):
             if err.errno != errno.ENOENT:
                 raise
 
+    def test_OPTIONS(self):
+        server_handler = AccountController(
+            {'devices': self.testdir, 'mount_check': 'false'})
+        req = Request.blank('/sda1/p/a/c/o', {'REQUEST_METHOD': 'OPTIONS'})
+        req.content_length = 0
+        resp = server_handler.OPTIONS(req)
+        self.assertEquals(200, resp.status_int)
+        for verb in 'OPTIONS GET POST PUT DELETE HEAD REPLICATE'.split():
+            self.assertTrue(
+                verb in resp.headers['Allow'].split(', '))
+        self.assertEquals(len(resp.headers['Allow'].split(', ')), 7)
+
     def test_DELETE_not_found(self):
         req = Request.blank('/sda1/p/a', environ={'REQUEST_METHOD': 'DELETE',
                                                   'HTTP_X_TIMESTAMP': '0'})
@@ -1600,7 +1612,7 @@ def start_response(*args):
         with mock.patch.object(self.controller, method,
                                new=mock_method):
             mock_method.replication = False
-            response = self.controller.__call__(env, start_response)
+            response = self.controller(env, start_response)
             self.assertEqual(response, method_res)
 
     def test_not_allowed_method(self):
@@ -1642,6 +1654,38 @@ def start_response(*args):
             response = self.controller.__call__(env, start_response)
             self.assertEqual(response, answer)
 
+    def test_call_incorrect_replication_method(self):
+        inbuf = StringIO()
+        errbuf = StringIO()
+        outbuf = StringIO()
+        self.controller = AccountController(
+            {'devices': self.testdir, 'mount_check': 'false',
+             'replication_server': 'true'})
+
+        def start_response(*args):
+            """Sends args to outbuf"""
+            outbuf.writelines(args)
+
+        obj_methods = ['DELETE', 'PUT', 'HEAD', 'GET', 'POST', 'OPTIONS']
+        for method in obj_methods:
+            env = {'REQUEST_METHOD': method,
+                   'SCRIPT_NAME': '',
+                   'PATH_INFO': '/sda1/p/a/c',
+                   'SERVER_NAME': '127.0.0.1',
+                   'SERVER_PORT': '8080',
+                   'SERVER_PROTOCOL': 'HTTP/1.0',
+                   'CONTENT_LENGTH': '0',
+                   'wsgi.version': (1, 0),
+                   'wsgi.url_scheme': 'http',
+                   'wsgi.input': inbuf,
+                   'wsgi.errors': errbuf,
+                   'wsgi.multithread': False,
+                   'wsgi.multiprocess': False,
+                   'wsgi.run_once': False}
+            self.controller(env, start_response)
+            self.assertEquals(errbuf.getvalue(), '')
+            self.assertEquals(outbuf.getvalue()[:4], '405 ')
+
     def test_GET_log_requests_true(self):
         self.controller.logger = FakeLogger()
         self.controller.log_requests = True

test/unit/container/test_server.py

@@ -301,6 +301,18 @@ def test_HEAD_invalid_format(self):
         resp = req.get_response(self.controller)
         self.assertEquals(resp.status_int, 400)
 
+    def test_OPTIONS(self):
+        server_handler = container_server.ContainerController(
+            {'devices': self.testdir, 'mount_check': 'false'})
+        req = Request.blank('/sda1/p/a/c/o', {'REQUEST_METHOD': 'OPTIONS'})
+        req.content_length = 0
+        resp = server_handler.OPTIONS(req)
+        self.assertEquals(200, resp.status_int)
+        for verb in 'OPTIONS GET POST PUT DELETE HEAD REPLICATE'.split():
+            self.assertTrue(
+                verb in resp.headers['Allow'].split(', '))
+        self.assertEquals(len(resp.headers['Allow'].split(', ')), 7)
+
     def test_PUT(self):
         req = Request.blank(
             '/sda1/p/a/c', environ={'REQUEST_METHOD': 'PUT',
@@ -2474,7 +2486,7 @@ def start_response(*args):
         method_res = mock.MagicMock()
         mock_method = public(lambda x: mock.MagicMock(return_value=method_res))
         with mock.patch.object(self.controller, method, new=mock_method):
-            response = self.controller.__call__(env, start_response)
+            response = self.controller(env, start_response)
             self.assertEqual(response, method_res)
 
     def test_not_allowed_method(self):
@@ -2515,6 +2527,38 @@ def start_response(*args):
             response = self.controller.__call__(env, start_response)
             self.assertEqual(response, answer)
 
+    def test_call_incorrect_replication_method(self):
+        inbuf = StringIO()
+        errbuf = StringIO()
+        outbuf = StringIO()
+        self.controller = container_server.ContainerController(
+            {'devices': self.testdir, 'mount_check': 'false',
+             'replication_server': 'true'})
+
+        def start_response(*args):
+            """Sends args to outbuf"""
+            outbuf.writelines(args)
+
+        obj_methods = ['DELETE', 'PUT', 'HEAD', 'GET', 'POST', 'OPTIONS']
+        for method in obj_methods:
+            env = {'REQUEST_METHOD': method,
+                   'SCRIPT_NAME': '',
+                   'PATH_INFO': '/sda1/p/a/c',
+                   'SERVER_NAME': '127.0.0.1',
+                   'SERVER_PORT': '8080',
+                   'SERVER_PROTOCOL': 'HTTP/1.0',
+                   'CONTENT_LENGTH': '0',
+                   'wsgi.version': (1, 0),
+                   'wsgi.url_scheme': 'http',
+                   'wsgi.input': inbuf,
+                   'wsgi.errors': errbuf,
+                   'wsgi.multithread': False,
+                   'wsgi.multiprocess': False,
+                   'wsgi.run_once': False}
+            self.controller(env, start_response)
+            self.assertEquals(errbuf.getvalue(), '')
+            self.assertEquals(outbuf.getvalue()[:4], '405 ')
+
     def test_GET_log_requests_true(self):
         self.controller.logger = FakeLogger()
         self.controller.log_requests = True