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Re: [vysper] questions

On Fri, Feb 18, 2011 at 13:15, Sasha Dolgy <sdolgy@...> wrote:
> Hi Bernd,
>
> I had a look at
> org.apache.vysper.xmpp.state.resourcebinding.ResourceRegistry ... so the way
> Vysper currently works today is that all sessions are stored in memory?  If
> vysper instance crashes, the resource id : session relationships aren't
> persisted anywhere?

No they aren't. But since XMPP uses long-living TCP/IP connections,
recovery from a server crash is equivalent to a
client/server-reconnect anyway.
This does not impose practical problems. (Leaving a reverse proxy setup aside.)
However, a cluster of XMPP servers for the exact same domain(!) would
need to share the ResourceRegistry datastructure.
(You could also have a federation of XMPP servers, but that'd mean
different users might have different account names like
you@..., me@...)

> It's been years since I properly programmed .. Have only gotten involved in
> Cassandra in the past four weeks and have made some significant mistakes and
> successes along the way.  For me, I am curious to deploy a compliant XMPP
> solution that potentially will leverage the user information i persist in
> cassandra.  i started work on writing a module in my application for user
> interactions (online / offline messages) only to stop suddenly late last
> night and ask myself why i'm re-inventing a wheel ....

Vysper can easily be embedded into other Java apps.

  Bernd

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Re: [vysper] questions

On Fri, Feb 18, 2011 at 16:35, Sasha Dolgy <sdolgy@...> wrote:
> Hi,
>
>  I have a working prototype using cassandra as a storage provider for
> [ org.apache.vysper.xmpp.authorization.AccountManagement/UserAuthorization
> ]
>
> verifyAccountExists(Entity jid)
> addUser(String username, String password)
>
> I started taking a look at the ResourceRegistry as you suggested.  Wouldn't
> a good first step be to abstract this and make it an interface and move the
> existing code into something that then implements it?

+1

> This way people could
> write different resource registry implementations so that we could see just
> how badly having it back onto Cassandra would be ; )

right 

> My code isn't pretty.  Having said that, what or where is the best way to
> share it?  Admittedly, it has been years since i've contributed something
> anywhere.

Please open a JIRA ticket (
https://issues.apache.org/jira/browse/VYSPER , registration required)
create a diff (IDEs, Unix, SVN tools etc support that) and attach it
to the JIRA issue.

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Re: [vysper] questions

On Fri, Feb 18, 2011 at 16:40, Sasha Dolgy <sdolgy@...> wrote:
> Hi Niklas,
>
> Although vysper doesn't currently support it, do the XMPP standards support
> it?
> -sd

I assume you're referring to the clustering...
No, XMPP does not provide an extension yet. There is one[1], but it is
"deferred" and not recommended for implementation.
The XSF ( xmpp.org ) is a very open-minded community. If you'd want to
go that far you could start a new spec effort there.

   Bernd

[1] http://xmpp.org/extensions/xep-0051.html

>
>
> On Fri, Feb 18, 2011 at 3:48 PM, Niklas Gustavsson <niklas@...>wrote:
>
>> I don't think this is sufficient since we do not currently support
>> relaying messages between users connected to the same domain but
>> different servers.
>>
>> /niklas
>>
>

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Re: [vysper] questions

On Fri, Feb 18, 2011 at 4:40 PM, Sasha Dolgy <sdolgy@...> wrote:
> Although vysper doesn't currently support it, do the XMPP standards support
> it?

The XMPP RFCs specifies the hostname lookup, using DNS SRV records.
But beyond that, I don't think there is any active spec for how to
cluster-enable XMPP servers.

/niklas