I'm configuring an installer for our product which, up until now, was distributed as a war file, usually on tomcat. Once tomcat has exploded the directory, the user has to open a properties file and set their database connection information. I'd like the installer to do this (we're using install4j) but there doesn't seem to be a built-in way to modify a text file inside a war file. I could just have the installer deploy the app as an exploded directory, which would save me the trouble here, but what do I lose by deploying like that instead of deploying the war?
It might work better to set up the database connection as a JNDI Datasource, rather than hand-editing a properties file inside the webapp/ directory. This is especially important if you want to allow users to re-deploy the application from the .WAR archive without overwriting their local configuration changes.
Of course, the JNDI setup isn't going to be trivially accomplished through the installer, either, since the mechanism used varies from app server to app server. However, any competent Java application server administrator should know how to configure a named datasource. Furthermore, by delegating responsibility to the app server, you allow your users to take advantage of connection pooling, clustering, and any other features provided by the datasource implementation bundled with their application server of choice.
Not much I would think - perhaps a bit of disk space, but if that's not a problem you'd be fine. Have you thought of having the installer generate the properties file and using a ZIP library (.WAR is really a .ZIP - rename it to a .ZIP and see what you get :) ) to replace or add it in?
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i am using wso2 api-manager 02.01.00 on a linux system. The Api-Manager is deployed at Folder A. The Databases (h2) are deployed ad Folder B which is not in Folder A. The datasources in /repository/conf/datasources/master-datasources.xml are pointing correctly to the databases in Folder B. I configured it like that, because i want do preserve the databases if there is a deployment. (Becaus a fiew Developer are using the API-Manager and they don't want to loose their Data.) But it seem, that WSO2AM_DB.h2.db is created new if there is an api-manager-depoyment. I think this, because i had a look to the DB-Size. I started with a Size of 1750KB for WSO2AM_DB.h2.db. I published a view API's in the Manager and the Size increases to 2774KB. Then i did a Deployment and the size returned to 1750KB.
Effect is that API-Store/Publisher says "There are no APIS published yet".
But i could see the APIS at Application Subscriptions and in Carbon Resources at /_system/governance/apimgt/applicationdata/provider/admin.
I tried to force a new Indexing with this, but it doesn't change anything.
Could i configure at any place, that the Database should not be created/manipulated at start?
Meanwhile i'm really desperated of not solving this problem.
Maybe you could help me.
Thank you for your Time.
WSO2 does not recommend to run on H2 database. You need to use a production database such as mysql, oracle, etc. H2 is only for tryouts.
Basically, WSO2 servers store data in databases as well as use the file system. For this kind of a deployment, you need to do the following.
Point to an external database. If you are using this for demo purposes, still you can go with the current mode (H2 database).
Use dep-sync. The content which comes under the WSO2_HOME/repository/deployment/server location needs to be preserved. You can use SVN based dep-sync or rsync. Basic idea is that for a new deployment, you need to have the data of the previous deployment.
Solr Indexing preservation. If you have hundreds/thousands of APIs in the system, it would take time for indexing. To avoid that you can copy the content of WSO2_HOME/solr to the new deployment.
My Java JSP application requires to store permanent files on the Tomcat web server. At the moment I save the files in the "/temp" folder of the System. But this folder gets cleared from time to time. Further, the current solution is hard-coded which makes it less flexible (e.g. when moving to another server).
I would like to now if there is a best practice for defining and accessing a permanent directory in this configuration. In detail, where is the best place to define the app file directory, and how would I access this from within my java application? The goal of this setup would be to cause the least effort when (a) updating the application (i.e. placing a new war file), and (b) moving from one server to another and OS (e.g. Unix, Windows, MacOS).
The research I have done on this topic so far revealed that the following would be solutions (possibly amongst others):
1.) Use of a custom subdirectory in the Tomcat installation directory.
What happens to the files if I deploy a new version on the tomcat via
war file?
Where do I define this directory to be accessed from
within my Java application?
2.) In a separate directory in the file system.
Which are good locations or ways to get the locations without knowing
the system?
Where do I define this directory to be accessed from
within my Java application?
Thank you for your advice!
Essentially, you are creating 'a database' in the form of some files. In the world of Java EE and servlet containers, the only really general approach to this is to configure such a resource via JNDI. Tomcat and other containers have no concept of 'a place for persistent storage for webapps'. If a webapp needs persistent storage, it needs to be configured via JNDI, or -D, or something you tell it by posting something to it. There's no convention or standard practice you can borrow.
You can pick file system pathname by convention and document that convention (e.g. /var/something on Linux, something similar on Windows). But you won't necessarily be aligned with what anyone else is doing.
Is it okay to place an oracle driver jar within the web application's /lib directory, or is it better practice to place it in tomcat's lib directory?
I'm wondering about this because on my local host, my web app runs fine with the jar in the web app's /lib directory, but when I move the web app to a real development server, I continue to receive null pointer exceptions when trying to close a connection pool object. I thought this issue may be why I'm unable to free the connection.
Thanks.
To answer the initial question, about placement of the .jar file, there are some things to consider:
Are there other apps on the same server that use this? If yes, and you want to ensure all of them use the same version, the placing on the server/lib folder would be better
If you want some flexibility in terms of what version of the .jar each app uses, then webapp/lib is better
If you are packaging your app as an ear or war, and there are size considerations, then the server/lib option has some advantages, given it makes sense considering the two points above.
If you run into classloader issues from dependencies, you may have to consider other jars when deciding on placement.
Whatever you decide, its best to make sure each jar exists only once in each apps classpath.
can any one tell me if I could deploy an IPad application with its pre-initialized database?
I'm using IOS developer Enterprise program account
Include the database as a resource in the bundle and clone it into the users document folder at launch.
The reason to clone is that you dont get write privileges on bundle resources.
Alternatively since this is not code you could download it from the corporate server at launch but since you are asking this question you probably dont want to do that.
Yes you can do it.
You can use sqlite in your ios application. You can create locally an prefilled sqlite database, and at this one to your xcode project.
In your project you must copy the sqlitedatabase from your resourcesfolder to the app's documents folder.
Depends on who's the developer of the app. If it's you, you can easily do so. Else, you won't be able (since apps are stored in a security sandbox).
If you really need to, you could consider jailbreaking them (you won't need a Enterprise Program though) so you can enter those sandboxes and add custom property lists to them.
Is it a good idea? I've never seen it done before.
The application in question is an enterprise project deployed as an EAR file on an app server. Properties include path to log file, name of JMS topic, etc. The intention being properties can be queried at runtime from the database, rather than having to redeploy the entire application, which might cause downtime and require developer/administrator attention.
How else would I modify runtime properties of the enterprise application?
Thanks.
You can do that or you can use properties file (config file) to store such info as I have seen this done on multiple projects. The preference of choosing between database and properties file is dependent on many factors but assuming the data are too little to be on database table, it's really fine for both solutions.