Confused about jrun-web.xml

Question

G'day there
I'm hoping someone can clarify the *actual* purpose of the
[cf]/WEB-INF/jrun-web.xml file, and how CF uses it.
My understanding of it was that it was the
JRun-internal-webserver's
equivalent of Apache's httpd.conf, or IIS's... err...
whereever IIS stores
its config. Basically a web server configuration file. So if
one wasn't
actually USING the JRun webserver for a given web site, then
that file is
just ignored.
However that understanding is incorrect, it seems.
I have this sort of set-up on my dev machine's file system:
C:\webroots
\webapp1root
\lib
\subapp
\myCfc.cfc
\webapp2root
\lib
\subapp
\myCfc.cfc
And my IIS default website (I'm just running XP Pro, so only
one website @
a time) is set up to have either webapp1root or webapp2root
as its webroot,
depending on which I am working on, at a given moment in
time. And the
website also has a virtual directory to "subapp", called...
"subapp".
Currently I'm working on webapp1, so was bemused that when I
did this:
createObject("component", "subapp.myCfc")
I was getting an instance of
C:\webroots\webapp2root\lib\subapp\myCfc.cfc
created, instead of the webapp1 version.
I spent rather too long ballocksing around checking virtual
directories, CF
mappings and all that sort of palarver, only to eventualy
find that I had a
residual mapping in my jrun-web.xml file pointing to
webapp2root's subapp
directory.
Once I removed that: all good.
Now to me, jrun-web.xml should be completely irrelevant to
that mix, as I'm
not using the JRun web server.
So obviously it's NOT just a web server config file. WTF *is*
it?
I have read various docs on the Adobe website, but they all
seem to be
written for an audience who would already know what the
author is on about
(hence making the doc a bit of a waste of time, in my view),
and it's all
completely impenetrable for me, as I'm just a CF developer
and haven't got
a clue about the inner workings of JRun (and, to be frank:
I'd like to keep
it that way if poss... JRun knowledge is not exactly a
marketable skill
What am I missing here?
Adam

Answer 1

I didn't skip over that part, but I probably wasn't as clear
as I needed to be. web.xml (and jrun-web.xml) are deployment
descriptors for a J2EE web application. That actually has nothing
to do with a "web server", it has to do with telling the
application server (JRun, in this case), any information it needs
to deploy the web application (ColdFusion, in this case). The
jrun-web.xml file simply includes stuff that isn't apart of the
J2EE spec but JRun developers thought it helpful to add in.
Again, _it has nothing to do with the "web server" as you see
it_.
If you are using IIS as your frontend web server, you're
still using JRun, the Application Server. In order for the JRun
Application Server (_not_ the web server) to start, it looks at
certain files to determine what web applications to deploy and how
to deploy them. Those files are web.xml and jrun-web.xml, among
others. The reason they're named "web.xml" and "jrun-web.xml" is
because it's deploying a "J2EE
Web Application". It has absolutely nothing to do with a web
server (an application that listens on port 80 or 443 and responds
to HTTP requests).
Let's see if I missed anything from your post:
quote:
G'day there
I'm hoping someone can clarify the *actual* purpose of the
[cf]/WEB-INF/jrun-web.xml file, and how CF uses it.
My understanding of it was that it was the
JRun-internal-webserver's
equivalent of Apache's httpd.conf, or IIS's... err...
whereever IIS stores
its config. Basically a web server configuration file. So if
one wasn't
actually USING the JRun webserver for a given web site, then
that file is
just ignored.
Nope. It's not a "web server configuration file". It's a web
application deployment descriptor. Lots different. It all stems
from the fact that ColdFusion is nothing more than a J2EE web
application being deployed on JRun.
quote:
{snip}
Now to me, jrun-web.xml should be completely irrelevant to
that mix, as I'm
not using the JRun web server.
So obviously it's NOT just a web server config file. WTF *is*
it?
See my first post, and clarification at the top of this post
quote:
I have read various docs on the Adobe website, but they all
seem to be
written for an audience who would already know what the
author is on about
(hence making the doc a bit of a waste of time, in my view),
and it's all
completely impenetrable for me, as I'm just a CF developer
and haven't got
a clue about the inner workings of JRun (and, to be frank:
I'd like to keep
it that way if poss... JRun knowledge is not exactly a
marketable skill
What am I missing here?
I have no idea how that mapping got in there in the first
place, but this is standard J2EE deployment descriptor stuff. Most
other J2EE servers (BEA, Glassfish, JBoss, etc) all have a
server-specific ___-web.xml deployment descriptor that goes along
with each web app, telling the Application Server the information
it needs to deploy the web app.
So, to sum up:
jrun-web.xml is not a web server configuration file.
jrun-web.xml is a JRun-specific J2EE Web Application
deployment descriptor file.
J2EE Web Application deployment descriptor files have nothing
to do with a web server (an application that responds to HTTP
requests), though the web.xml and jrun-web.xml files do tell JRun
how to interpret the requests passed to it via the IIS ISAPI
filter.
I don't know how you got that mapping in there in the first
place.