[http-replicator-users] released 4.0alpha1

[Gertjan v. Z. <ger...@gm...>]

Finally.


Today I finally managed to release a replicator that is 100% to my
satisfaction. Which does not mean to say it is bug free, nor feature
complete. But it is a version that I can work at without the nagging feeling
that things should change drastically, and that all patching up is lost
effort.

The new server has a shining new engine, the fiber module, which I started
documenting some time ago in README.devel included in the package - work in
progress but the idea is there. In short: each separate transaction is a
generator object (available since python 2.3; a very strict dependency) that
yields state information to the scheduler. Compared to the asyncore
framework that I used previously the new system is much more flexible, in a
way emulating a multi-threaded setup while still being the lightweight
single-threaded application it always was. The new flexibility made it
possible to implement often requested features such as:

   - server-side download resuming
   - ftp support
   - bandwidth shaping
   - support for ipv6 (although this should be tested!);

and to fix outstanding issues that I was not able to fix within the rigid
asyncore framework. Most notably, the often reported problem with frozen
downloads that never closed is finally solved by putting a (configurable)
timeout to all waiting states. Another annoying problem was the situation
that transactions could be joined only after server response, with the
result that simultaneously started downloads would never join force. All
this is fixed. Text output should also be a lot clearer now that it is
gathered per transaction and printed upon return; see the project screenshot
for demo output. The old behaviour is still available as a --debug mode,
which also prints extra information about current waiting states.

However much has changed on the inside, on the outside the new replicator
should be a continuation of previous versions. Some features have has gone
missing - most notably cache browsing - but all of those I intend to restore
in later alpha releases. After that I will switch to beta releases and stop
adding big things until the server is thoroughly tested and released as 4.0.
Needless to say you are highly encouraged to help me test this software and
report your findings on this list. The unit-test script that is included in
the package should be a good starting point - I actually expect most
problems found this way to be bugs in the script, but these should be fixed
just as well. Any further questions, problems, wishes, etc, please send them
to this list so that others can benefit and I don't have to make the same
replies over and over again ;P

And a very happy 2008 to all of you!

Gertjan