pysyncml 0.2.0

A pure-python implementation of the SyncML adapter framework and protocol.

Welcome to the pysyncml library, a pure-python implementation of the SyncML adapter framework and protocol. SyncML is a protocol to synchronize opaque objects between multiple clients and a server. Although pysyncml does provide some utilities to synchronize certain types of content and is therefore useful as-is, it is primarily intended to be used as a library by other applications that want to add data synchronization support via SyncML.

Important

2013/12/15: pysyncml is currently beta. That means it has not had much “real-world” experience and you may encounter many bugs. However, it is being actively developed, so check back in a couple of months.

If you decide to use it anyway, you are strongly encouraged to do a full backup of your data before you use pysyncml to synchronize production data.

Working components as of 0.2.0:

• Client-side SyncML framework with support for CRUD operations, i.e. Add/Replace/Delete Sync commands.

• Server-side SyncML framework with support for CRUD operations, i.e. Add/Replace/Delete Sync commands, BUT it is not recommended to use server-side yet, as some API changes are expected.

• Server-side conflict detection and multi-policy resolution.

• Native support for “note” datatype.

Goals

The pysyncml project has the following goals, some of them diverge critically from other SyncML implementations and are the reasons for creating a new package instead of building on other existing implementations:

• Can be installed and used with a single “pip install pysyncml” (or easy_install).

• Is python 2.7+ and 3+ compatible.

• Implements a sufficiently large subset of the SyncML 1.2.2 (a.k.a. the OMA Data Synchronization specification) as to be interoperable with other implementations without necessarily being “conformant”.

• Can be easily integrated into SQLAlchemy based projects to store data in the application’s database instead of separated out (so that integrated database triggers and cascading can be applied).

• Can be extended in order to make properly crafted clients able to operate in “distributed” mode - this means that in the absence of a network, SyncML client peers are able to synchronize with each other in the anticipation that the central server may or may not eventually become available again.

• Differentiates as little as possible between “client” and “server” modes to enable the previous goal.

• Makes basic synchronization easy and complicated synchronization possible by providing standard implementations for commonly used approaches, while allowing these components to be overriden or extended.

• Provides basic command line tools for commonly synchronized data types.

• Provides a framework of server-push notifications which are transport agnostic.

• Auto-discovery of SyncML server URI locations; i.e. finding the “right” paths to bind object types is done automatically instead of needing error-prone user configuration.

Limitations

It is the goal of the project to get a minimally functional library going in the shortest possible timeframe. To that end, the following features of SyncML will NOT be implemented until a later phase, even if this means that the library does not provide a conformant implementation:

• NOT supported: filtering of searches or synchronization targets.

• NOT supported: data split over multiple messages.

• NOT supported: soft-deletes.

• NOT supported: memory constraint management.

• NOT supported: suspend, resume and busy signaling.

• NOT supported: MD5 authentication scheme.

• NOT supported: per-database-layer authorization.

Installation

Installation of pysyncml is near-trivial with PIP:

$ pip install pysyncml

or, using easy_install:

$ easy_install pysyncml

Pre-Requisites

Python 2.7 or better is required, as the following is “taken for granted” by the pysyncml developers:

• relative imports,

• “with” context manager statement,

• native ElementTree,

• ternary expression (EXPR if EXPR else EXPR),

• and something else which was found to not work in 2.6.4 but the author cannot remember what it was and does not wish to run into that limitation ever again…

Documentation

For downloaded packages, please see the generated documents in the “doc” directory, otherwise you can find links to the latest how-to and API reference documentation at pysyncml.