I have to implement a special conditions check in the existing WAR application deployed in Tomcat 7. I have created a Servlet that perform necessary checks on it's init() method. So, during WAR startup everything is being checked.
Now, if I want the WAR application to be accessible only when all the conditions are met and some condition did not work - how can I stop the deployment of the WAR? In the other words how can I prevent access to the WAR application?
As an example of such condition: for example, I found that the database is not properly updated and therefore application will crash on attempt to access the DB.
Related
I am new to using the JBoss 7.1.1 server and am confused by a behavior that I have observed.
My JBoss server is deploying the six jBPM .war files (designer, drools-guvnor, jbpm-form-builder, jbpm-gwt-console, jbpm-gwt-console-server, jbpm-human-task-war) which I have placed in the .\jboss-as-7.1.1.Final\standalone\deployments folder.
When I launched the server for the very first time it detected these files and deployed them. I see the deploymentNNN and tempNNN folders appear in the .\jboss-as-7.1.1.Final\standalone\tmp\vfs folder. This is similar to the behavior I'm familiar with from my use of the tomcat server.
I then shut the server down and observe that the two folders created in .\jboss-as-7.1.1.Final\standalone\tmp\vfs are retained but their contents are automatically deleted. When I restart the server it once again deploys the six jBPM files into a new pair of folders in .\jboss-as-7.1.1.Final\standalone\tmp\vfs.
This is very surprising because no changes have been made to the six jBPM files and the problem is that this redeployment takes 3 to 4 minutes.
If this was just happening in a "production" environment then perhaps this would not be much of an issue. However, I am trying to integrate the JBoss server into use with Eclipse Kepler in a development environment and having to wait 3 to 4 minutes for each code change and server launch is not practical.
1) Can anyone explain why JBoss goes to the trouble to redeploy files that have not been changed?
2) Is this a behaviour that can be changed through a configuration setting?
3) Is there any settings where we can stop the jboss to redeploy the war files when it restarted
Thank you,
All
In order to stop JBoss from re-deploying your apps (and deleting on shutdown),
try deploying the apps in unpacked form.
extract the files to {name}.war directories (e.g /designer.war, /drools-guvnor.war)
and then deploy these directories (i.e copy them to the deployments folder)
Alternatively, try to deploy them using the JBoss CLI
Deploying differently won't change the fact that at startup JBOSS reloads your application to the JVM.
This can take time because your application stores data from database to your server memory. (You could as well be hitting this WFLY-925 bug... Or the one they are talking about here...)
The thing is you normally don't need to restart your server completely when redeploying. You can hot-deploy your module - see also full doc. at Auto-deploy mode. (make sure the feature isn't disabled
If you need some context to be reloaded, I advise you have a specific procedure in your code that you can call to reload all cached info. instead of restarting completely (e.g. have a call to a specific URL from your application do it...)
Is there anyway to change certain web.xml parameters of an already deployed application in the glassfish?
If you change directly in the file-system, no one will understand later, why and when the changes have been done. So this is bad!
But it's easy: Just change the web.xml of the deployed application and restart the glassfish domain. You will find the web.xml somewhere near
/PATH/TO/glassfish3/glassfish/domains/DOMAIN/applications/APP-NAME/WAR-NAME/WEB-INF/web.xml
if deployed in a standalone instance. Otherwise it is somewhere below the ..../nodes folder.
Edit: In a cluster environment, a sync from the deployment manager will override your changes.
I just packaged my maven web application into a war file, upload it to remote server which has installed the tomcat environment. After I unpacked my war file and put all files in the /webapps/ROOT directory, I run bin/startup.sh to fire up the tomcat.
This just works fine, but when I intend to change my web application and redeploy it on the server, I don't know how to do that seamlessly, that is to say, not letting the users who is using my website lose any request.
Could anyone give me some idea? Thanks a lot!
You can always use manager app coming with tomcat to deploy a war without bringing the website down, even from a remote machine using browser.
http://tomcat.apache.org/tomcat-7.0-doc/manager-howto.html#Deploy_A_New_Application_Remotely
You may use reverse proxy as door of you site. After deploying your "second" war into Tomcat, you can change the configuration of reverse proxy and reload it. The reloading of reverse proxy is very speedy, so that it likes "seamless" re-deployment of Java web application. After the reloading of reverse proxy, you could un-deploy "first" war of application safely.
This way to re-deploy is especially useful if the application needs time for initialization(for example: including ORM, Spring Framework...).
There are few concerns about using multiple-war-at-the-same-time:
1) There will be two applications(although, temporary) running on your Tomcat concurrently, make sure there is nothing hazard about concurrent executing. For example: scheduled jobs
2) You need to confirm that there is enough memory on Tomcat to live with two web applications, or Tomcat may hang.
3) Be meticulous about Java.lang.OutOfMemory: PermGen Space problem
I'm trying to verify some conditions on application startup, such as the presence of critical files in the system.
To do this, I'm using a SerlvetContextListener, which tests for a bunch of conditions on startup.
How can I make so that the application rejects the deployment in Tomcat, if any of these conditions is not met? I could throw an exception, and catch that in the logs, but I'd like the application not to start at all.
Even failing Tomcat service startup would be a solution.
What's the simplest way? Should I try connecting to the Tomcat manager and undeploy the app?
Well...
According to your original question, you'd like the application to "not start at all" if certain files aren't there (or other conditions aren't met). Logically, it follows that the checking of the conditions can't possibly be a part of the application (if the checking is to be done as a part of the application - say, upon startup - then the application must be started for those checks to take place).
So:
If you don't want the application to start at all unless certain conditions are met, then your solution must be external to the application. For example, you could write your own Tomcat startup script that will check for your conditions first, and only then start Tomcat up.
If you don't mind the application starting and performing the checks, then the ServletContextListener is precisely what you should take advantage of. Throwing an exception from within contextInitialized() will result in the application being "unavailable" for serving requests. Alternatively, you could communicate with Tomcat's MBeans to stop the application if checks don't pass.
i'm about to deploy two different but dependent war-files into a single jboss (AS 4.2.x GA)
One implements some webservices (jax-ws) exposing their interfaces through
a wsdl. The other one is a (say) web frontend using the aformentioned webservices. When I drop both warfiles to $JBOSS_HOME/server/default/deploy at the same time I can see that the first gets deployed (somehow) but the second one gets stuck and the entire jboss is not responding.
When I deploy them one after another, everything is fine (it just works:)
Is there a way to tell jboss that deployment of warfile2.war has to wait
for warfile1.war to finish deployment before starting deployment of warfile2.war?
Is there a way to determine programatically wheter a given 'service' is deployed
and ready?
I'm wonder what happens when both wars are present and jboss is restarted?
Kind regards,
Jay Wee.
To answer your last question first, JBoss will deploy the contents of its deploy directory in alphabetical order. If you drop two WAR files into a running server's deploy directory, the results are unpredictable, but should be safe, so I'm not sure what's going on there.
By the way you describe the dependency, it sounds like when a user uses the frontend WAR, it calls the web service WAR, and that on startup there's no link between the two? Could anyone be trying to use the frontend WAR while the web service WAR is still deploying? Which WAR comes first alphabetically?
As a possible solution, when you have two WAR files that depend on each other, you should consider packing them both into a single EAR file. That way JBoss will deploy them together in a controlled way.
What about implementing a listener in the web frontend waiting for a successfull head request to the wsdl on localhost?
Thats right. backend.war is deployed before frontend.war.
I deployed it on my local jboss and nobody else has acces to it.
What I can see when i debug into jboss is that the frontend accesses the backend wsdl (https://localhost:9999/app/svc?wsdl ) hangs while jboss is not ready.
\at Arne Burmeister: the listener approach doesen't help. the listener is called to early in the process: I can connect to the backendWsdlUrl but backenWsdlUrl.getConnection().getOutputstream() hangs
I think I'll give the ear a try. Is there a good documentation on how
to pack things together in an ear? (skaffman already pointed me into the right direction)
Thanks a lot to all who help so far,
Jan