
The connect method of ssync_sender tells the remote connection that it's
going to send a valid HTTP chunked request, but if the remote end needs
to respond with an error of any kind sender throws HTTP right out the
window, picks up his ball, and closes the socket down hard - much to the
surprise of the eventlet.wsgi server who up to this point had been
playing along quite nicely with this 'SSYNC' nonsense assuming that
everyone here is consenting mature adults.
If you're going to make a "Transfer-Encoding: chunked" request have the
good decency to finish the job with a proper '0\r\n\r\n'. [1]
N.B. It might be possible to handle an error status during the
initialize_request phase with some sort of 100-continue support, but
honestly it's not entirely clear to me when the server isn't going to
close the connection if the client is still expected to send the body
[2] - further if the error comes later during missing_check or updates
we'll for sure want to send the chunk transfer termination line before
we close down the socket and this way we cover both.
1. Really, eventlet.wsgi shouldn't be so blasted brittle about this [3]
2. https://lists.w3.org/Archives/Public/ietf-http-wg/2005AprJun/0007.html
3. c3ce3eef0b
Closes-Bug #1489587
Change-Id: Ic17c6c3075553f8cf6ef6213e62a00282f0d01cf
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://docs.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
.
If you would like to start contributing, check out these notes to help you get started.
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