Source Syncer
-------------

Source Syncer is an Open Source product from ZeOmega that allows live zope
objects to be synchronized from one Zope Instance to another without going
through the tedious export / transfer / import procedure. It is very easy to
use and also provides very robust security and access control, so that it can
be used for synchronization between zope development and production sites. It
has the ability to view at a glance which objects are out-of sync and also
allows you to view a color coded diff against the destination object, for many
types of objects.

Methodology
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It uses message digests to detect changes in object bodies that is returned
using the objects document_src() method. So the entire source is not sent
across the network ,instead the message digest is created and sent which is
relatively small insize.Thus detecting the differences between source and
destination is done with very little overhead and suitable for highlatency
networks . A primary difference between the Source Syncer and the ZSyncer
product, which is also used for code sync is that, Source Syncer does not
depend on time stamps and most importantly syncs only the source and not the
entire object. So Objects at either end continue to retain all other
attributes. This is very useful when production objects have properties set on
them that should NOT be changed.  It also works when the source and
destination servers are at different time zones as content editors may not be
working in the same time zone as the production servers. It uses xml-rpc and
supports SSL as well as non-secure HTTP. It reuses a lot of code for network
communication from the original ZSyncer product.


Installation
------------

Place the VSyncer directory in your zope Products directory as usual with
product installation. You need to do this for all Zope servers that you wish
to use as sources or destinations. Be sure that you can make HTTP connections
from the source server to the destination server (and the Zope port). Source
Syncer cannot work without this.The managers id that is used in the source,
should have a login id on destination with the same password.