6ff644b945
When the number of account/container or container/object replicas are different, Swift had a few misbehaviors. This commit fixes them. * On an object PUT/POST/DELETE, if there were 3 object replicas and only 2 container replicas, then only 2 requests would be made to object servers. Now, 3 requests will be made, but the third won't have any X-Container-* headers in it. * On an object PUT/POST/DELETE, if there were 3 object replicas and 4 container replicas, then only 3/4 container servers would receive immediate updates; the fourth would be ignored. Now one of the object servers will receive multiple (comma-separated) values in the X-Container-* headers and it will attempt to contact both of them. One side effect is that multiple async_pendings may be written for updates to the same object. They'll have differing timestamps, though, so all but the newest will be deleted unread. To trigger this behavior, you have to have more container replicas than object replicas, 2 or more of the container servers must be down, and the headers sent to one object server must reference 2 or more down container servers; it's unlikely enough and the consequences are so minor that it didn't seem worth fixing. The situation with account/containers is analogous, only without the async_pendings. Change-Id: I98bc2de93fb6b2346d6de1d764213d7563653e8d |
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| bin | ||
| doc | ||
| etc | ||
| locale | ||
| swift | ||
| test | ||
| tools | ||
| .coveragerc | ||
| .functests | ||
| .gitignore | ||
| .gitreview | ||
| .mailmap | ||
| .probetests | ||
| .unittests | ||
| AUTHORS | ||
| babel.cfg | ||
| CHANGELOG | ||
| CONTRIBUTING.md | ||
| LICENSE | ||
| MANIFEST.in | ||
| README.md | ||
| setup.cfg | ||
| setup.py | ||
| tox.ini | ||
Swift
A distributed object storage system designed to scale from a single machine to thousands of servers. Swift is optimized for multi-tenancy and high concurrency. Swift is ideal for backups, web and mobile content, and any other unstructured data that can grow without bound.
Swift provides a simple, REST-based API fully documented at http://doc.openstack.org/.
Swift was originally developed as the basis for Rackspace's Cloud Files and was open-sourced in 2010 as part of the OpenStack project. It has since grown to include contributions from many companies and has spawned a thriving ecosystem of 3rd party tools. Swift's contributors are listed in the AUTHORS file.
Docs
To build documentation install sphinx (pip install sphinx), run
python setup.py build_sphinx, and then browse to /doc/build/html/index.html.
These docs are auto-generated after every commit and available online at
http://docs.openstack.org/developer/swift/.
For Developers
The best place to get started is the "SAIO - Swift All In One". This document will walk you through setting up a development cluster of Swift in a VM. The SAIO environment is ideal for running small-scale tests against swift and trying out new features and bug fixes.
You can run unit tests with .unittests and functional tests with
.functests.
Code Organization
- bin/: Executable scripts that are the processes run by the deployer
- doc/: Documentation
- etc/: Sample config files
- swift/: Core code
- account/: account server
- common/: code shared by different modules
- middleware/: "standard", officially-supported middleware
- ring/: code implementing Swift's ring
- container/: container server
- obj/: object server
- proxy/: proxy server
- test/: Unit and functional tests
Data Flow
Swift is a WSGI application and uses eventlet's WSGI server. After the
processes are running, the entry point for new requests is the Application
class in swift/proxy/server.py. From there, a controller is chosen, and the
request is processed. The proxy may choose to forward the request to a back-
end server. For example, the entry point for requests to the object server is
the ObjectController class in swift/obj/server.py.
For Deployers
Deployer docs are also available at http://docs.openstack.org/developer/swift/. A good starting point is at http://docs.openstack.org/developer/swift/deployment_guide.html
You can run functional tests against a swift cluster with .functests. These
functional tests require /etc/swift/test.conf to run. A sample config file
can be found in this source tree in test/sample.conf.
For Client Apps
For client applications, official Python language bindings are provided at http://github.com/openstack/python-swiftclient.
Complete API documentation at http://docs.openstack.org/api/openstack-object-storage/1.0/content/
For more information come hang out in #openstack-swift on freenode.
Thanks,
The Swift Development Team