Inline - per my usual:
On 12/17/2013 10:23 AM, Ray Holme wrote:
First: Thanks for clarifying my understanding of XML tags AND FIXING my typo.
and apologies for top-posting - I had hoped I was making it easier by
restating the crux of the problem and shortening everyone's read.
AND for the record, yahoo is NO longer including the prior message which is what
I intended originally. I am not sure when they changed things, but I am NOT a
yahoo
fan anymore. I tried to get your message included above.
I'm using yahoo for my mailing lists, all others end up in gmail.
However I'm using Thunderbird and IMAP, so I can control how my mail
works a bit better.
------------------------
BUT SO far, I have totally failed with linking - below is the detail.
Quick recap - for those with shorter memories than even mine. :=<]
"appName" has a top level directory .../webapps/appName/appName_tour"
which contains a bunch of very large files - "a demo tour"
the goal is to separate this from the WAR file
(later in another app, I want photos separated for same reason
BUT in the case HERE, the files are read only, nothing written to dir).
a) try 1 - using links (moved the directory to /opt/appName_tour) and did a
symbolic link
under the application directory (MS systems cannot do this)
--- .../webapps/appName/META-INF/context.xml contains 3 lines
<?xml version="1.0" encoding="UTF-8"?>
<Context allowLinking="true">
</Context>
When I try to run the linked demo I get this in the popup window generated:
HTTP Status 404 - /appName/appName_tour/appNamev3.html
type Status report
message /appName/appName_tour/appNamev3.html
description The requested resource is not available.
Apache Tomcat/7.0.35
So, a few questions are in order here:
1. Where did you get the Tomcat from?
If it's from a distribution repackage, components get scattered all
over. However this should not impact linking.
2. Are you running with SELinux enabled?
If SELinux is enforcing and you've installed Tomcat from a distribution
package, you may be running into SELinux issues. What does sealert say?
3. General permissions
Does the user running Tomcat have proper permissions for
/opt/appName_tour? You'll need read/execute access for all intervening
directories, and read access for the files.
4. What user is Tomcat running as?
If you're binding to port 80, then you'll at least have to start out as
a privileged user. Typically this is done with a jsvc wrapper. Don't run
Tomcat (or any server) as root.
The strange thing here is that I thought I had this one was working a few
days back.
b) try 2 - using aliases - removed the symbolic link and left the real directory
(/opt/appName_tour exists but there is NO .../webapps/appName/appName_tour)
---.../webapps/appName/META-INF/context.xml contains 3 lines
<?xml version="1.0" encoding="UTF-8"?>
<Context aliases="/appName_tour=/opt/appName_tour">
</Context>
SAME RESULTS in the popup windowas in a) above.
c) try 3 use Virtual Directory Context - left directories setup as in b (above)
(/opt/appName_tour exists but there is NO .../webapps/appName/appName_tour)
---.../webapps/appName/META-INF/context.xml contains 5 lines
<?xml version="1.0" encoding="UTF-8"?>
<Context>
<Resources className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/appName_tour=/opt/appName_tour">
</Resources>
</Context>
SAME RESULTS in the popup windowas in a) and b) above.
Footnote: I also tried making an empty directory in the webapps/appName
directory
instead of leaving it NOT THERE at all. Same results.
Painful Footnote: For some obscure reason, I must separate each trial by quite
a bit of time (30 mins)
- JUST THIS application goes nuts getting a database connection (looks like
an xinetd shutdown)
I get a null pointer to the startup of the app which requires the DB
- there are FOUR apache-tomcat application directories here - all use
databases (different)
restarting tomcat does NOT affect any of three others - they ALL work fine
- after 30 minutes of tomcat DOWN, this app starts fine too
there are NO warnings in /var/log/messages about xinetd refusing
connections (have seen before)
just starts and stops of xinetd <-> db connectors (normal heavy startup
usage)
- without these changes to context.xml (a-c enumerated above) (i.e. the tour
is a real directory)
this application restarts just fine every time I restart tomcat
(and did in fedora 8, 12, 14, 16 too)
--- this is weird and painful or I would have completed all these tests hours
ago
Hmm . . . . Lots of speculation here. How are the files referenced in
your application? It seems that if the physical files are available,
then the application works fine. If the physical files are not
available, then the database has problems (firebird under xinetd,
perhaps?) and you get 404 errors. Does the application scan a directory
and populate the database on startup? Does the database need to know
where the files are? Does the database need read access to the files?
So many questions, so little info . . .
Here are a couple of thoughts to try.
1. Write a small test application
I wrote one - took about 10 minutes - to test how this all works since
I've not done this before. You should be able to write a quick
application, drop it in a locally installed Tomcat downloaded from
tomcat.apache.org, and verify that it works.
2. Determine what's different
I outlined some of the questions above. Basically, they are probably
either permission issues (real, SELinux), or how your application
accesses the resources (looking for files in the wrong place). I can't
think of other issues at the moment.
3. Fix what's different
If it's not a permissions issue, then it's more likely an application
issue. We'd need to know more, and at that point we've wandered well off
the Tomcat mailing list topics.
. . . just my two cents.
/mde/
On Monday, December 16, 2013 5:19 PM, Mark Eggers <its_toas...@yahoo.com> wrote:
Replies inline.
Note, people on this mailing list frown on top-posting (see items 6 and
7 here: http://tomcat.apache.org/lists.html). It does make the reply and
response difficult to follow without rereading the entire thread.
Please either reply inline or at the end, so people late to the party
(or those of us with short / fragmented memory :-p) can remember what's
going on.
On 12/16/2013 1:00 PM, Ray Holme wrote:
I have been trying three scenarios. So far one works (least security and not
good for all OS versions).
Again thanks to both Marks for the pointers, but I am afraid they are not
working yet.
My goal is to enable one directory to be used which is outside the application
(and tomcat too)
.../webapps/mywebapp hierarchy
which mywebapp.war will replace with a new release
use 1: to store/retrieve images locally to a machine
under application control (db stores names of files)
use 2: to store a static movie - demo (no update - this is the simple test
case I try)
The goal is to get this stuff out of the war file (leaving nothing, an empty
dir, or a link as needed - see below). All of the below require apache/tomcat
to be down when you make the changes, then restart to test
a) IF you have linux (or unix) or osx - you can do symbolic linking
simply move the directory and link (my case below):
cd ..../webapps/mywebapp; mv images /opt; ln -s /opt/images
and to enable symbolic linking to other directories on your machine (all
of them)
create a ..../webapps/mywebapp/META-INF/context.xml file (or edit the one
you have)
<?xml version="1.0" encoding="UTF-8"?>
<Context allowLinking="true"> </Context>
advantages for this method: works simply
faults: MS os's don't do symbolic; also opens up ALL linking (security
issues? probably)
BUT THERE ARE 2 other SAFER more restrictive ways below, both also done in
the same context.xml file (if I can get either of them to work - the
examples often say the server.xml file, but there is only one of them in the
top tomcat conf directory, which has NO context references - but if they go
there, then path= probably needs to be specified.)
b)
<?xml version="1.0" encoding="UTF-8"?>
<Context aliases="/images=/opt/images" />
</Context>
c)
<?xml version="1.0" encoding="UTF-8"?>
<Context <Resources className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/images=/opt/images" />
</Context>
I hope that you meant:
<Context>
<Resources className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/images=/opt/images" />
</Context>
-------------------------
These are both more security conscious and might should work for MS
(with MS correct paths such as d:\images)
Which of these is simpler and/or better - I have no idea. Net comparisons
don't say.
but the VirtualDirContext.html pages say: DO NOT USE FOR PRODUCTION
of course- they don't say why NOT
I'm not sure that this is valid any more.
Why both require the escaped greater than sign, beats me too. "/>"
It's not an escaped greater than sign. It's how one closes an empty tag
in XML. You could also have written it the following way:
<Context>
<Resources className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/images=/opt/images">
</Resources>
</Context>
I would have thought it would be simply ">" on the 2nd and 3rd lines resp.
(b and c)
NEITHER OF THESE WORKED FOR ME! (so far and I have tried many variants)
Do I have to have the symbolic link (in Linux - I did for a) obviously)
or should this be a plain empty directories (like Linux/Unix mount
points)
or should there be no "../webapps/myapp/images" anything at all?
There should be nothing in your web application at all. However,
according to the documentation, the alias path (and by extension, the
VirtualDirContext) are searched first, so it shouldn't matter as long as
the target directory exists.
In the manual version there are more parameters, but most folks say to drop
"path=mywebapp"
and the rest seem to not be relevant to what I am doing so I cut them out.
Maybe that is the problem.
Here is the example I found under VirtualDirContext online
<Context path="/mywebapp" docBase="/Users/theuser/mywebapp/src/main/webapp" >
<Resources className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/pictures=/Users/theuser/mypictures,/movies=/Users/theuser/mymovies"
/>
<Loader className="org.apache.catalina.loader.VirtualWebappLoader"
virtualClasspath="/Users/theuser/mywebapp/target/classes" />
<JarScanner scanAllDirectories="true" />
</Context>
The example you quoted was for the directory structure listed above the
example.
Do not use path if you're deploying in the appBase directory defined in
server.xml ($CATALINA_BASE/webapps by default), which you are.
Do not use docBase at all - this is for locating an application outside
of the appBase directory defined in server.xml.
Now using the following context.xml:
<Context>
<Resources className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/images=/opt/images" />
</Context>
Your application should end up with <img> tags looking like the following:
<img src="images/picture1.png" alt="Picture 1">
Things are a bit nicer if you use the core tag libraries, and of course
if you're using HTML 5 you'll need to close the tag (the above is HTML
4.01 Transitional).
I wrote a quick web application to access some pictures in my home
directory with:
<?xml version="1.0" encoding="UTF-8"?>
<Context>
<Resources className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/pictures=/home/mdeggers/Pictures"/>
</Context>
This was done on Fedora 19, Tomcat 7.0.42, JRE 1.7.0_45, and it worked
as advertised.
I also tried the following, which worked:
<?xml version="1.0" encoding="UTF-8"?>
<Context aliases="/pictures=/home/mdeggers/Pictures">
</Context>
Links in my index.jsp:
<img src="pictures/snapshot1.png" alt="snapshot 1"><br>
<img src="pictures/snapshot2.png" alt="snapshot 2"><br>
<img src="pictures/snapshot3.png" alt="snapshot 3"><br>
<img src="pictures/snapshot4.png" alt="snapshot 4"><br>
I normally use the core tag library, so those links would be:
<img
src='<c:url value="/pictures/snapshot1.png"/>' alt="snapshot 1"><br>
<img
src='<c:url value="/pictures/snapshot2.png"/>' alt="snapshot 2"><br>
<img
src='<c:url value="/pictures/snapshot3.png"/>' alt="snapshot 3"><br>
<img
src='<c:url value="/pictures/snapshot4.png"/>' alt="snapshot 4"><br>
. . . . just my two cents.
/mde/
On Sunday, December 15, 2013 7:39 PM, Christopher Schultz
<ch...@christopherschultz.net> wrote:
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
Martin,
On 12/15/13, 4:52 PM, Martin Gainty wrote:
Mark I assume you're referring to Virtual DirContext...? <Context
path="/mywebapp" docBase="/Users/theuser/mywebapp/src/main/webapp"
You shouldn't use the "path" attribute, here. You should know this.
<Resources
className="org.apache.naming.resources.VirtualDirContext"
extraResourcePaths="/WEB-INF/classes=/Users/theuser/mywebapp/target/classes,/pictures=/Users/theuser/mypictures,/movies=/Users/theuser/mymovies"/>
VirtualDirContext
is not necessary, but it is one option.
- -chris
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org
