On May 19, 2009, at 3:09 PM, David Jencks wrote:
On May 19, 2009, at 12:42 PM, Bill Stoddard wrote:
Lin Sun wrote:
One quick way would be allow users to start a tomcat server from a
geronimo tomcat javaee5 assembly or little G tomcat assembly(say
geronimo.sh start tomcatOnly=true). It is possible to just launch
the tomcat server, and read the configuration files (conf/
server.xml,
etc) and start a tomcat server from a geronimo tomcat assembly, by
using the Catalina.java provided by tomcat. But this server/app
would have no relationship with geronimo, other than using the jars
provided by the geronimo tomcat assembly. The deployed app would
be
tracked only by tomcat, and not by geronimo. We should be able to
achieve this without adding any new jars.
If we need more than that, I can for seen the following issues that
need investigation -
1. We'll have to provide better server integration with tomcat and
be
able to read the server configuration from tomcat's server
configuration files, along with using config.xml configurations.
This would be an absolute minimal requirement. Would this be
really difficult?
2. We'll have to migrate user's app automatically for the user, when
the user's app is a bit complicated that contains any need to
require
a geronimo-web.xml
This is where things get more interesting.... lots of permutations
and edge cases to consider.
I'm not enough of a tomcat expert to know exactly what information a
server.xml contains so I'm not quite sure how much the following
makes sense.
I think I would approach this by building a namespace aware builder
that can interpret documents following the server.xml schema and
construct the entire tomcat server from it. In other words, instead
of starting with our current tomcat6 plugin, the builder would
construct a replacement for it from the server.xml. If server.xml
contains info on apps that are deployed in the tomcat instance, this
could perhaps hook into or extend the current TomcatModuleBuilder to
also set up plugins for each web app involved.
The first part here might not be too hard. IMO if we treat the
server.xml as a geronimo plan that would be acceptable. I'd
recommend trying jaxb rather than using xmlbeans. I don't know how
practical this would turn out to be but it's worth starting with.
I personally think this is too large an addition to plan to get into
2.2. However if a motivated person shows up with something working
before we solve the other problems I think we could consider it.
2.2 is already so much later than we had planned I don't want to
hold it up for any new features after the other problems have been
solved.
I played with something like this on the plane today..... it might not
take more that a couple days to get _something_ working that
interprets server.xml files. It turns out there's no schema for
tomcat configurations so it may be an adventure interpreting the same
files they do.
We might be able to copy their digester configuration but replace
defaults with geronimo classes instead of tomcat classes. I find
digester grammar so hard to understand however that I started by
generating a schema from a sample file and modifying it to fit the
digeter rules.
My current idea is to have a TomcatServerGBean that has a server.xml
as an attribute, which it reads into a jaxb tree, which we call a
"construct(ClassLoader cl)" method on to set up the tomcat objects.
If this works it should be fairly easy.... no idea if it will actually
work though.
Next step would be a builder that, given a server.xml, sets up such a
gbean.
thanks
david jencks
thanks
david jencks
Lin
On Mon, May 18, 2009 at 3:49 PM, Bill Stoddard
<[email protected]> wrote:
I know G can't consume tomcat configs today, but is this a
feature that
could be developed for G 2.2?
Say I have an application successfully deployed and running under
Tomcat..
wouldn't it be nice if I were able to drop the tomcat server
config into a
Geronimo-Tomcat assembly, start the server, deploy the app and be
up and
running in seconds. I'm talking about a seamless, zero effort/
zero touch
migration from Tomcat to a Geronimo-Tomcat assembly. Is it
possible? If
not, what simplifying assumptions could be made to 'mostly'
achieve a
zero-touch migration?
What are the primary challenges with consuming a tomcat config
unchanged
with a G-Tomcat assembly? Same Q's apply for Jetty... what's
'doable'
with-in reason?
Thanks,
Bill
