diff options
Diffstat (limited to 'gluster/swift/obj')
-rw-r--r-- | gluster/swift/obj/expirer.py | 160 | ||||
-rw-r--r-- | gluster/swift/obj/server.py | 78 |
2 files changed, 227 insertions, 11 deletions
diff --git a/gluster/swift/obj/expirer.py b/gluster/swift/obj/expirer.py new file mode 100644 index 0000000..564a2c9 --- /dev/null +++ b/gluster/swift/obj/expirer.py @@ -0,0 +1,160 @@ +# Copyright (c) 2016 Red Hat +# +# 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. + +# This import will monkey-patch Ring and other classes. +# Do not remove. +import gluster.swift.common.constraints # noqa + +import errno +import os + +from gluster.swift.common.utils import rmobjdir + +from swift.obj.expirer import ObjectExpirer as SwiftObjectExpirer +from swift.common.http import HTTP_NOT_FOUND +from swift.common.internal_client import InternalClient, UnexpectedResponse +from swift.common.utils import ThreadPool + +EXCLUDE_DIRS = ('.trashcan', '.glusterfs') + + +class GlusterSwiftInternalClient(InternalClient): + + def __init__(self, conf_path, user_agent, request_tries, + allow_modify_pipeline=False, devices=None): + super(GlusterSwiftInternalClient, self).__init__( + conf_path, user_agent, request_tries, allow_modify_pipeline) + self.devices = devices + + def get_account_info(self, account): + # Supposed to return container count and object count in gsexpiring + # account. This is used by object expirer only for logging. + return (0, 0) + + def delete_container(self, account, container, acceptable_statuses=None): + container_path = os.path.join(self.devices, account, container) + try: + os.rmdir(container_path) + except OSError as err: + if err.errno != errno.ENOENT: + raise + + def iter_containers(self, account): + account_path = os.path.join(self.devices, account) + for container in os.listdir(account_path): + if container in EXCLUDE_DIRS: + continue + container_path = os.path.join(account_path, container) + if os.path.isdir(container_path): + yield {'name': container.encode('utf8')} + + def iter_objects(self, account, container): + container_path = os.path.join(self.devices, account, container) + # TODO: Use a slightly better implementation of os.walk() + for (root, dirs, files) in os.walk(container_path): + for f in files: + obj_path = os.path.join(root, f) + obj = obj_path[(len(container_path) + 1):] + yield {'name': obj.encode('utf8')} + + +class ObjectExpirer(SwiftObjectExpirer): + + def __init__(self, conf, logger=None, swift=None): + + conf_path = conf.get('__file__') or '/etc/swift/object-expirer.conf' + self.devices = conf.get('devices', '/mnt/gluster-object') + # Do not retry DELETEs on getting 404. Hence default is set to 1. + request_tries = int(conf.get('request_tries') or 1) + # Use our extended version of InternalClient + swift = GlusterSwiftInternalClient( + conf_path, 'Gluster Swift Object Expirer', request_tries, + devices=self.devices) + # Let the parent class initialize self.swift + super(ObjectExpirer, self).__init__(conf, logger=logger, swift=swift) + + self.reseller_prefix = conf.get('reseller_prefix', 'AUTH').strip() + if not self.reseller_prefix.endswith('_'): + self.reseller_prefix = self.reseller_prefix + '_' + + # nthread=0 is intentional. This ensures that no green pool is + # used. Call to force_run_in_thread() will ensure that the method + # passed as arg is run in a real external thread using eventlet.tpool + # which has a threadpool of 20 threads (default) + self.threadpool = ThreadPool(nthreads=0) + + def _delete_tracker_object(self, container, obj): + container_path = os.path.join(self.devices, + self.expiring_objects_account, + container) + tracker_object_path = os.path.join(container_path, obj) + + try: + os.unlink(tracker_object_path) + except OSError as err: + if err.errno in (errno.ENOENT, errno.ESTALE): + # Ignore removal from another entity. + return + elif err.errno == errno.EISDIR: + # Handle race: Was a file during crawl, but now it's a + # directory. There are no 'directory marker' objects in + # gsexpiring volume. + return + else: + raise + + # This part of code is very similar to DiskFile._unlinkold() + dirname = os.path.dirname(tracker_object_path) + while dirname and dirname != container_path: + if not rmobjdir(dirname, marker_dir_check=False): + # If a directory with objects has been found, we can stop + # garbage collection + break + else: + # Traverse upwards till the root of container + dirname = os.path.dirname(dirname) + + def pop_queue(self, container, obj): + """ + In Swift, this method removes tracker object entry directly from + container database. In gluster-swift, this method deletes tracker + object directly from filesystem. + """ + self.threadpool.force_run_in_thread(self._delete_tracker_object, + container, obj) + + def delete_actual_object(self, actual_obj, timestamp): + """ + Swift's expirer will re-attempt expiring if the source object is not + available (404 or ANY other error) up to self.reclaim_age seconds + before it gives up and deletes the entry in the queue. + + Don't do this in gluster-swift. GlusterFS isn't eventually consistent + and has no concept of hand-off nodes. If actual data object doesn't + exist (404), remove tracker object from the queue (filesystem). + + However if DELETE fails due a reason other than 404, do not remove + tracker object yet, follow Swift's behaviour of waiting till + self.reclaim_age seconds. + + This method is just a wrapper around parent class's method. All this + wrapper does is ignore 404 failures. + """ + try: + super(ObjectExpirer, self).delete_actual_object( + actual_obj, timestamp) + except UnexpectedResponse as err: + if err.resp.status_int != HTTP_NOT_FOUND: + raise diff --git a/gluster/swift/obj/server.py b/gluster/swift/obj/server.py index 1d8d418..3e27cc3 100644 --- a/gluster/swift/obj/server.py +++ b/gluster/swift/obj/server.py @@ -14,16 +14,19 @@ # limitations under the License. """ Object Server for Gluster for Swift """ +import errno +import os from swift.common.swob import HTTPConflict, HTTPNotImplemented -from swift.common.utils import public, timing_stats, replication -from gluster.swift.common.exceptions import AlreadyExistsAsFile, \ - AlreadyExistsAsDir +from swift.common.utils import public, timing_stats, replication, mkdirs from swift.common.request_helpers import split_and_validate_path - from swift.obj import server from gluster.swift.obj.diskfile import DiskFileManager +from gluster.swift.common.fs_utils import do_ismount +from gluster.swift.common.ring import Ring +from gluster.swift.common.exceptions import AlreadyExistsAsFile, \ + AlreadyExistsAsDir class GlusterSwiftDiskFileRouter(object): @@ -55,6 +58,9 @@ class ObjectController(server.ObjectController): """ # Replaces Swift's DiskFileRouter object reference with ours. self._diskfile_router = GlusterSwiftDiskFileRouter(conf, self.logger) + self.devices = conf.get('devices', '/mnt/gluster-object') + self.swift_dir = conf.get('swift_dir', '/etc/swift') + self.object_ring = self.get_object_ring() def container_update(self, *args, **kwargs): """ @@ -65,15 +71,65 @@ class ObjectController(server.ObjectController): """ return - def delete_at_update(self, *args, **kwargs): - """ - Update the expiring objects container when objects are updated. + def get_object_ring(self): + return Ring(self.swift_dir, ring_name='object') - For Gluster, this is a no-op as there are no container DB entries - to be created that tracks objects to be expired. Objects to be - expired will be determined by crawling the filesystem directly. + def _create_expiring_tracker_object(self, object_path): + try: + + # Check if gsexpiring volume is present in ring + if not any(d.get('device', None) == self.expiring_objects_account + for d in self.object_ring.devs): + raise Exception("%s volume not in ring" % + self.expiring_objects_account) + + # Check if gsexpiring is mounted. + expiring_objects_account_path = \ + os.path.join(self.devices, self.expiring_objects_account) + mount_check = self._diskfile_router['junk'].mount_check + if mount_check and not do_ismount(expiring_objects_account_path): + raise Exception("Path %s doesn't exist or is not a mount " + "point" % expiring_objects_account_path) + + # Create object directory + object_dir = os.path.dirname(object_path) + try: + mkdirs(object_dir) + except OSError as err: + mkdirs(object_dir) # handle race + + # Create zero-byte file + try: + os.mknod(object_path) + except OSError as err: + if err.errno != errno.EEXIST: + raise + except Exception as e: + self.logger.error("Creation of tracker object %s failed: %s" % + (object_path, str(e))) + + def async_update(self, op, account, container, obj, host, partition, + contdevice, headers_out, objdevice, policy): """ - return + In Openstack Swift, this method is called by: + * container_update (a no-op in gluster-swift) + * delete_at_update (to PUT objects into .expiring_objects account) + + The Swift's version of async_update only sends the request to + container-server to PUT the object. The container-server calls + container_update method which makes an entry for the object in it's + database. No actual object is created on disk. + + But in gluster-swift container_update is a no-op, so we'll + have to PUT an actual object. We override async_update to create a + container first and then the corresponding "tracker object" which + tracks expired objects scheduled for deletion. + """ + object_path = os.path.join(self.devices, account, container, obj) + + threadpool = self._diskfile_router[policy].threadpools[objdevice] + threadpool.run_in_thread(self._create_expiring_tracker_object, + object_path) @public @timing_stats() |