Problem Context:
When GlassFish starts, the bootstrap process starts an OSGi framework
(default is Felix), which is configured to start one of our bundles
called osgi-main.jar. This primordial bundle is responsible for
installing all the OSGi bundles available in modules directory tree. It
also takes care of updating modified bundles and deleting removed
bundles from OSGi runtime so as to keep the OSGi persistent cache in
sync with the GlassFish installation. It then starts all other bundles
that are necessary for server to start. This includes any bundle that
has a Startup service or Init service. When such a service requires
service from some other bundle, that bundle is started in the process.
So, in essence, not all bundles are started automatically when the
server starts. This lazy startup of bundles gives us good startup time
and memory footprint. /But, it causes problems when we host bundles
developed elsewhere in the modules dir/. e.g. Felix Web Console which
can be used to manage OSGi runtime. Those bundles do not necessarily
contain a Startup service to be started automatically. Unless they are
started, they are not much useful. Although we have a domain specific
autostart directory where users can drop OSGi bundles to be started
automatically when server starts, such a domain specific directory can't
be used to install update centre packages. As a result, we can't make
useful bundles like the one mentioned earlier made available via update
centre.
Proposal:
I am proposing to add an installation specific autostart directory,
where user can drop an OSGi bundle for it to be started automatically.
We already have necessary infrastructure to implement it. I am open to
the choice of names. The ones that come to my mind are
modules/autostart/ and modules-autostart/. I am also of the opinion that
these bundles should have same security privileges as bundles in
modules/, as this directory is owned by the user who owns the
installation, so it is already protected. These bundles will be started
after server startup is complete unless there is a deployed application
that uses a package exported by any of these bundles, so they can't
typically affect startup time.
Opinions, objections?
Thanks,
Sahoo
p.s.: This issue came up during a conversation with Abhijit earlier today.