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

7 files changed, 222 insertions, 33 deletions

diff --git a/swift/account/server.py b/swift/account/server.py
index cf160e9e2..1d892fba4 100644
--- a/swift/account/server.py
+++ b/swift/account/server.py
@@ -32,6 +32,7 @@ from swift.common.utils import get_logger, hash_path, public, \
 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.swob import HTTPAccepted, HTTPBadRequest, \
 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 @@ class AccountController(object):
             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
diff --git a/swift/common/base_storage_server.py b/swift/common/base_storage_server.py
new file mode 100644
index 000000000..4eb024b27
--- /dev/null
+++ b/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
diff --git a/swift/container/server.py b/swift/container/server.py
index 6ef713188..a17434214 100644
--- a/swift/container/server.py
+++ b/swift/container/server.py
@@ -38,6 +38,7 @@ from swift.common.bufferedhttp import http_connect
 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, \
@@ -71,7 +72,7 @@ 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
@@ -79,16 +80,13 @@ class ContainerController(object):
                     '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 @@ class ContainerController(object):
             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
diff --git a/swift/obj/server.py b/swift/obj/server.py
index 3ee7e0688..72672609b 100644
--- a/swift/obj/server.py
+++ b/swift/obj/server.py
@@ -40,6 +40,7 @@ from swift.common.exceptions import ConnectionTimeout, DiskFileQuarantined, \
     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 @@ class EventletPlungerString(str):
         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 @@ class ObjectController(object):
         <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 @@ class ObjectController(object):
         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 @@ class ObjectController(object):
             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)
diff --git a/test/unit/account/test_server.py b/test/unit/account/test_server.py
index c18c57edb..d4c514d27 100644
--- a/test/unit/account/test_server.py
+++ b/test/unit/account/test_server.py
@@ -55,6 +55,18 @@ class TestAccountController(unittest.TestCase):
             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 @@ class TestAccountController(unittest.TestCase):
         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 @@ class TestAccountController(unittest.TestCase):
             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
diff --git a/test/unit/container/test_server.py b/test/unit/container/test_server.py
index bbab11491..44f19de9a 100644
--- a/test/unit/container/test_server.py
+++ b/test/unit/container/test_server.py
@@ -301,6 +301,18 @@ class TestContainerController(unittest.TestCase):
         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 @@ class TestContainerController(unittest.TestCase):
         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 @@ class TestContainerController(unittest.TestCase):
             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
diff --git a/test/unit/obj/test_server.py b/test/unit/obj/test_server.py
index 27bc9637f..bc0ac4274 100755
--- a/test/unit/obj/test_server.py
+++ b/test/unit/obj/test_server.py
@@ -1122,6 +1122,20 @@ class TestObjectController(unittest.TestCase):
             os.path.basename(os.path.dirname(disk_file._data_file)))
         self.assertEquals(os.listdir(quar_dir)[0], file_name)
 
+    def test_OPTIONS(self):
+        conf = {'devices': self.testdir, 'mount_check': 'false'}
+        server_handler = object_server.ObjectController(
+            conf, logger=debug_logger())
+        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 \
+                REPLICATION'.split():
+            self.assertTrue(
+                verb in resp.headers['Allow'].split(', '))
+        self.assertEquals(len(resp.headers['Allow'].split(', ')), 8)
+
     def test_GET(self):
         # Test swift.obj.server.ObjectController.GET
         req = Request.blank('/sda1/p/a/c', environ={'REQUEST_METHOD': 'GET'})
@@ -4089,7 +4103,7 @@ class TestObjectController(unittest.TestCase):
                              mock.MagicMock(return_value=method_res))
         with mock.patch.object(self.object_controller, method,
                                new=mock_method):
-            response = self.object_controller.__call__(env, start_response)
+            response = self.object_controller(env, start_response)
             self.assertEqual(response, method_res)
 
     def test_not_allowed_method(self):
@@ -4146,6 +4160,38 @@ class TestObjectController(unittest.TestCase):
                                ' 1234',),
                               {})])
 
+    def test_call_incorrect_replication_method(self):
+        inbuf = StringIO()
+        errbuf = StringIO()
+        outbuf = StringIO()
+        self.object_controller = object_server.ObjectController(
+            {'devices': self.testdir, 'mount_check': 'false',
+             'replication_server': 'true'}, logger=FakeLogger())
+
+        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.object_controller(env, start_response)
+            self.assertEquals(errbuf.getvalue(), '')
+            self.assertEquals(outbuf.getvalue()[:4], '405 ')
+
     def test_not_utf8_and_not_logging_requests(self):
         inbuf = StringIO()
         errbuf = StringIO()