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<title>Historical Documents</title>
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<h1>Historical Documents</h1>
<p>Here are documents which contain no pertinent information or documentation.
People from the Twisted team have published them, and they serve as interesting
land marks and thoughts. Please don't look here for documentation -- however,
if you are interested in the history of Twisted, or want to quote from these
documents, feel free. Remember, however -- the documents here may contain
wrong information -- they are not updated as Twisted is, to keep their
historical value intact.</p>
<h2>2003</h2>
<h3>Python Community Conference</h3>
<p>These papers were part of the <a href= "http://python.org/pycon/"
>Python Community Conference</a> (PyCon) in March of 2003.</p>
<!-- Do we want to link slides too? -->
<dl>
<dt><a href="2003/pycon/deferex.html"><cite>Generalization of Deferred Execution in Python</cite></a></dt>
<dd><p>A deceptively simple architectural challenge faced by many
multi-tasking applications is gracefully doing nothing. Systems that
must wait for the results of a long-running process, network message, or
database query while continuing to perform other tasks must establish
conventions for the semantics of waiting. The simplest of these is
blocking in a thread, but it has significant scalability problems. In
asynchronous frameworks, the most common approach is for long-running
methods to accept a callback that will be executed when the command
completes. These callbacks will have different signatures depending on
the nature of the data being requested, and often, a great deal of code
is necessary to glue one portion of an asynchronous networking system to
another. Matters become even more complicated when a developer wants to
wait for two different events to complete, requiring the developer to
"juggle" the callbacks and create a third, mutually incompatible
callback type to handle the final result.</p>
<p>This paper describes the mechanism used by the Twisted framework for
waiting for the results of long-running operations. This mechanism,
the <code>Deferred</code>, handles the often-neglected problems of
error handling, callback juggling, inter-system communication and code
readability.</p></dd>
<dt><a href="2003/pycon/applications/applications.html"><cite>Applications of the Twisted Framework</cite></a></dt>
<dd><p>Two projects developed using the Twisted framework are described;
one, Twisted.names, which is included as part of the Twisted
distribution, a domain name server and client API, and one, Pynfo, which
is packaged separately, a network information robot.</p></dd>
<dt><a href="2003/pycon/conch/conch.html"><cite>Twisted.Conch: SSH in Python with Twisted</cite></a></dt>
<dd><p>Conch is an implementation of the Secure Shell Protocol (currently
in the IETF standarization process). Secure Shell (or SSH) is a popular
protocol for remote shell access, file management and port forwarding
protected by military-grade security. SSH supports multiple encryption and
compression protocols for the wire transports, and a flexible system of
multiplexed channels on top. Conch uses the Twisted networking framework
to supply a library which can be used to implement both SSH clients and
servers. In addition, it also contains several ready made client programs,
including a drop-in replacement for the OpenSSH program from the OpenBSD
project.</p></dd>
<dt><a href="2003/pycon/lore/lore.html"><cite>The Lore Document Generation Framework</cite></a></dt>
<dd><p>Lore is a documentation generation system which uses a limited
subset of XHTML, together with some class attributes, as its source
format. This allows for lower barrier of entry than many other similar
systems, since HTML authoring tools are plentiful as is knowledge of
HTML writing. As an added advantage, the source format is viewable
directly, so that even if Lore is not available the documentation is
useful. It currently outputs LaTeX and HTML, which allows for most
use-cases.</p></dd>
<dt><a href="2003/pycon/pb/pb.html"><cite>Perspective Broker: <q>Translucent</q> Remote Method calls in Twisted</cite></a></dt>
<dd><p>One of the core services provided by the Twisted networking
framework is <q>Perspective Broker</q>, which provides a clean, secure,
easy-to-use Remote Procedure Call (RPC) mechanism. This paper explains the
novel features of PB, describes the security model and its implementation,
and provides brief examples of usage.</p></dd>
<dt><a href="2003/pycon/releasing/releasing.html"><cite>Managing the Release of a Large Python Project</cite></a></dt>
<dd><p>Twisted is a Python networking framework. At last count, the
project contains nearly 60,000 lines of effective code (not comments or
blank lines). When preparing a release, many details must be checked, and
many steps must be followed. We describe here the technologies and tools
we use, and explain how we built tools on top of them which help us make
releasing as painless as possible.</p></dd>
<dt><a href="2003/pycon/twisted-reality/twisted-reality.html"><cite>Twisted Reality: A Flexible Framework for Virtual Worlds</cite></a></dt>
<dd><p>Flexibly modelling virtual worlds in object-oriented languages has
historically been difficult; the issues arising from multiple
inheritance and order-of-execution resolution have limited the
sophistication of existing object-oriented simulations. Twisted
Reality avoids these problems by reifying both actions and
relationships, and avoiding inheritance in favor of automated
composition through adapters and interfaces.</p></dd>
</dl>
<h2>Previously</h2>
<ul>
<li><a href="ipc10paper.html">The paper Glyph and Moshe presented in
IPC10</a></li>
<li><a href="ipc10errata.html">The errata published in IPC10 against the
paper.</a></li>
<li><a href="twisted-debian.html">A paper Moshe wrote about Twisted and
Debian.</a></li>
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