Re: [Engine-devel] Improve classpath building

On 06/05/2012 04:41 PM, Yair Zaslavsky wrote: > On 06/05/2012 03:53 PM, Juan Hernandez wrote: >> Hello all, >> >> I would like to propose an improvement in the way we build class-paths >> in the tools associated to the engine. At the moment we have at least >> two different ways to build classpaths: >> >> 1. Hard coded in the scripts, with maybe some variables: >> >> CP=$EAR_LIB/engine-encryptutils.jar:$EAR_LIB/engine-compat.jar:... >> >> This depends a lot on where we place the jar files, and we need to place >> them in different places in different environments if we want to adhere >> to common packaging practices. >> >> 2. Use the build-classpath script: >> >> CP=`build-classpath engine-encryptutils engine-compat ...` >> >> This depends less on the place we put them, but it doesn't work in >> development environments where some jars are not installed to the proper >> system locations. >> >> None of these is good for all environments. >> >> I would like to replace this classpath building logic with an script >> that performs the task in an smarter way and that works in all our >> environments (production, development, Fedora, RHEL, etc). >> >> My proposal is to create a "engine-java" script that we should use >> always when invoking java programs. This script will receive the same >> parameters that the "java" launcher receives, but the "-cp" or >> "-classpath" options will contain not the absolute name of the jar >> files, but just a simple jar name instead, something like >> "commons-logging", "commons-codec" or "engineencryptutils". The script >> will extract the "-cp" or "-classpath" options given and use them to do >> a search of the jar files in the locations where they can be in >> different environments: >> >> /usr/share/java >> /usr/share/java/ovirt-engine >> /usr/share/ovirt-engine/engine.ear >> /usr/share/ovirt-engine/engine.ear/lib >> <your jboss development installation>/engine.ear >> <your jboss development installation>/engine.ear/lib >> >> In addition the script will check that all the give jar files exist and >> will abort the execution if any of them is missing. >> >> Find attached the initial version of the proposed script. >> >> Let me know what you think. > > Excellent idea! > I would like to add - > I already saw the work you did on engine-manage-domains. > When we work on development machines, we might have the jars reside in > different places. Yes, this is one of the motivations for this new engine-java script, the fact that we can't expect the build-classpath script to work in all environments, specially development environments. > I wanted to create a script that will allow for example to use > build-classpath on spring-ldap-core, but I did not have a soft link for > that in /usr/share/java (is that what I needed to do?) Yes, just create the link in /usr/share/java and it should work. If you want to keep it compatible with the Fedora spring-ldap package create it as "/usr/share/java/spring-ldap/spring-ldap-core.jar", then you should be able to use it with "build-classpath spring-ldap/spring-ldap-core". > I guess we will have to differentiate between the need of dev and > production for this script. I would rather try to make it work in all the environments without change, but I know that is quite difficult.