How to generate different deployables from the same Maven project? - maven-2

I have a situation that I'm sure must be fairly common. I have some Maven-built applications that deploy to different types of application server - like Tomcat, JBoss, etc.
The build processes 'tunes' the deployable artifact to the specific target type of application server (for example, different included dependencies, context roots, other config). This tuning is controlled with build profiles (-Ptomcat, -Pjboss etc)
So, for a given version of my application, I need to run builds that produce different deployables. I run mvn -Ptomcat clean package for example and I get an artifact in my /target directory that is the tomcat-tuned version.
The best approach I've been able to come up with so far is to specify finalnames for the artifacts that include the profile information, but for that approach, I'm not sure how to configure Maven to copy the final artifact off to some specific location so that the next build for a different type doesn't overwrite it.
Is this a good approach? If so, how can I achieve that final copy?
Or is there a better way?

You'll need to use Maven Assembly Plugin.

Related

How to make a maven project buildable for the customer

We have a project which should be buildable by the customer using maven. It has some open source dependencies that are mavenized (no problem), some that aren't mavenized, proprietary stuff (oracle jdbc driver) and some internal stuff.
Until now we had everything but the first category packaged with the project itself in a local repository (repository with file://path-in-project-folder specified in the projects pom.xml).
We would love to move these out of the project, as we are about to use them in other projects as well. Currently we plan to use nexus as an internal maven repository.
Whats the best practice to make such dependencies/maven repositories available to the customer so he can continue to build the project.
Ideas so far:
Customer sets up a nexus repository as well, we somehow deploy all these non-public dependencies to his repository (like a mirror)
We provide a 'dumb' dump/snapshot of the non-public dependencies, customer adds this snapshot to this settings.xml as a repository, (but how is this possible).
Make our internal nexus repo available to the customers build server (not an option in our case)
I'm wondering how others solve these problems.
Thank you!
Of course, hosting a repository of some kind is a straightforward option, as long as you can cover the uptime / bandwidth / authentication requirements.
If you're looking to ship physical artifacts, you'll find this pattern helpful: https://brettporter.wordpress.com/2009/06/10/a-maven-friendly-pattern-for-storing-dependencies-in-version-control/
That relies on the repository being created in source control - if you want a project to build a repository, consider something like: http://svn.apache.org/viewvc/incubator/npanday/trunk/dist/npanday-repository-builder/pom.xml?revision=1139488&view=markup (using the assembly plugin's capability to build a repository).
Basically, by building a repository you can ship that with the source code and use file:// to reference it from within the build.
There are two options:
Document exactly what artifacts you need to compile which are not
available via Maven Central
Implement Nexus and make a export with Nexus give the export
to customer and they need to do a import of it. I'm not sure
if you come to licenses issues.
I assumed that you already have a Repository Manager already but it reads like you didn't.

Maven2: Possible to deploy depends on artifact classifier?

In fact I have 2 different problems, but I think they are kind of related:
I have an artifact, with an assembly descriptor set which will build an extra JAR (with extra classifier). By default, Maven2/3 will deploy the assembly generated together with the main artifact to remove Maven repository. Is there any way that I can deploy only the main artifact but not the assembly?
I have an artifact, in which I have jar plugin generate another artifact with different classifier (more specific, an EJB artifact, and I generate an client JAR). I want to deploy only the client JAR to Maven repo coz I think the main EJB artifact is not really going to be shared by other project. Is it possible to do so?
Thanks a lot
editied to provide more info:
The reason for avoiding deploy the EJB, is because the EJB main artifact is not going to be depended by other project except the containing project. The containing project will build a EAR (which contains the EJB), and normally we only need that build locally (by mvn package). However, the EJB client is something that we will deploy to our repo to let other project share when they need to communicate with our application.
Honestly it doesn't harm to deploy the EJB too, but I just want to see if I can save unnecessary waste of disk space on our repository.
Similarly, for deploying assembly, it is because the project is something we want to deploy to let other project to depends on. However, when building that project, we also have a separate assembly created on the same time (for example, an all-in-one executable jar) which we only need that built locally, and it is not something that other projects will depends on.
Turn off the 'attach' option to the assembly plugin. Then it won't be officially an artifact and it won't deploy; it will just lurk in the target directory, sulking that you don't love it as much as it's elder sibling and plot revenge.
Based on your first question i would like to know why do you create the supplemental assembly which is usually deployed as well as the main artifact. If you wan't to prevent you can put the creation of the assembly into a profile but this means you will not generate the supplemental artifact in your usual build only by activating the profile.

Maven best practice for generating artifacts for multiple environments [prod, test, dev] with CI/Hudson support?

I have a project that need to be deployed into multiple environments (prod, test, dev). The main differences mainly consist in configuration properties/files.
My idea was to use profiles and overlays to copy/configure the specialized output. But I'm stuck into if I have to generate multiple artifacts with specialized classifiers (ex: "my-app-1.0-prod.zip/jar", "my-app-1.0-dev.zip/jar") or should I create multiple projects, one project for every environment ?!
Should I use maven-assembly-plugin to generate multiple artifacts for every environment ?
Anyway, I'll need to generate all them at once so it seams that the profiles does not fit ... still puzzled :(
Any hints/examples/links will be more than welcomed.
As a side issue, I'm also wondering how to achieve this in a CI Hudson/Bamboo to generate and deploy these generated artifacts for all the environments, to their proper servers (ex: using SCP Hudson plugin) ?
I prefer to package configuration files separately from the application. This allows you to run the EXACT same application and supply the configuration at run time. It also allows you to generate configuration files after the fact for an environment you didn't know you would need at build time. e.g. CERT
I use the "assembly" tool to zip up each domain's config files into named files.
I would use the version element (like 1.0-SNAPSHOT, 1.0-UAT, 1.0-PROD) and thus tags/branches at the VCS level in combination with profiles (for environments specific things like machines names, user name passwords, etc), to build the various artifacts.
We implemented a m2 plugin to build the final .properties using the following approach:
The common, environment-unaware settings are read from common.properties.
The specific, environment-aware settings are read from dev.properties, test.properties or production.properties, thus overriding default values if necessary.
The final .properties files is written to disk with the Properties instance after reading the files in given order.
Such .properties file is what gets bundled depending on the target environment.
We use profiles to achieve that, but we only have the default profile - which we call "development" profile, and has configuration files on it, and we have a "release" profile, where we don't include the configuration files (so they can be properly configured when the application is installed).
I would use profiles to do it, and I would append the profile in the artifact name if you need to deploy it. I think it is somewhat similar to what Pascal had suggested, only that you will be using profiles and not versions.
PS: Another reason why we have dev/ release profiles only, is that whenever we send something for UAT or PROD, it has been released, so if there is a bug we can track down what the state of the code was when the application was released - it is easier to tag it in SVN than trying to find its state from the commit history.
I had this exact scenario last summer.
I ended up using profiles for each higher environment with classifiers. Default profile was "do no harm" development build. I had a DEV, INT, UAT, QA, and PROD profile.
I ended up defining multiple jobs within Hudson to generate the region specific artifacts.
The one thing I would have done differently was to architect the projects a bit differently so that the region specific build was outside of the modularized main project. That was it would simply pull in the lastest artifacts for each specific build rather than rebuild the entire project for each region.
In fact, when I setup the jobs, the QA and PROD jobs were always setup to build off of a tag. Clearly this is something that you would tailor to your specific workplace rules on deployment.
Try using https://github.com/khmarbaise/multienv-maven-plugin to create one main WAR and one configuration JAR for each environment.

Maven - installing artifacts to a local repository in workspace

I'd like to have a way in which 'mvn install' puts files in a repository folder under my source (checkout) root, while using 3rd party dependencies from ~/.m2/repository.
So after 'mvn install', the layout is:
/work/project/
repository
com/example/foo-1.0.jar
com/example/bar-1.0.jar
foo
src/main/java
bar
src/main/java
~/.m2/repository
log4j/log4j/1.2/log4j-1.2.jar
(In particular, /work/project/repository does not contain log4j)
In essense, I'm looking for a way of creating a composite repository that references other repositories
My intention is to be able to have multiple checkouts of the same source and work on each without overwriting each other in the local repository with 'install'. Multiple checkouts can be because of working on different branches in cvs/svn but in my case it is due to cloning of the master branch in git (in git, each clone is like a branch). I don't like the alternatives which are to use a special version/classifier per checkout or to reinstall (rebuild) everything each time I switch.
Maven can search multiple repositories (local, remote, "fake" remote) to resolve dependencies but there is only ONE local repository where artifacts get installed during install. It would be a real nightmare to install artifacts into specific locations and to maintain this list without breaking anything, that would just not work, you don't want to do this.
But, TBH, I don't get the point. So, why do you want to do this? There might be alternative and much simpler solutions, like installing your artifacts in the local repository and then copying them under your project root. Why wouldn't this work? I'd really like to know the final intention though.
UPDATE: Having read the update of the initial question, the only solution I can think of (given that you don't want to use different versions/tags) would be to use two local repositories and to switch between them (very error prone though).
To do so, either use different user accounts (as the local repository is user specific by default).
Or update your ~/.m2/settings.xml each time you want to switch:
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0
http://maven.apache.org/xsd/settings-1.0.0.xsd">
<localRepository>${user.home}/.m2/repository</localRepository>
<!--localRepository>${user.home}/.m2/repository2</localRepository-->
...
</settings>
Or have another settings.xml and point on it using the --settings option:
mvn install --settings /path/to/alternate/settings.xml
Or specify the alternate location on the command line using the -Dmaven.repo.local option:
mvn -Dmaven.repo.local=/path/to/repo
These solutions are all error prone as I said and none of them is very satisfying. Even if you might have very good reasons to work on several branches in parallel, your use case (not rebuilding everything) is not very common. Here, using distinct user accounts migh be the less worse solution IMO.
This is INDEED possible with the command line, and in fact is quite useful. For example, if you want to create an additional repo under your Eclipse project, you just do:
mvn install:install-file -DlocalRepositoryPath=repo \
-DcreateChecksum=true -Dpackaging=jar \
-Dfile=%2 -DgroupId=%3 -DartifactId=%4 -Dversion=%5
It's the "localRepositoryPath" parameter that will direct your install to any local repo you want.
I have this in a batch file that I run from my project root, and it installs the file into a "repo" directory within my project (hence the % parameters). So why would you want to do this? Well, let's you say you are professional services consultant, and you regularly go into customer locations where you are forced to use their security hardened laptops. You copy your self-contained project to their laptop from a USB stick, and presto, you can do your maven build no problem.
Generally, if you are using YOUR laptop, then it makes sense to have a single local repo that has everything in it. But to you who got cocky and said things like "why would you want to do that", I have some news...the world is a bigger place with more options than you might realize. If you are using laptops that are NOT yours, and you need to build your project on that laptop, get the resulting artifact, and then remove your project directory (and the local repo you just used), this is the way to go.
As to why you would want to have 2 local repos, the default .m2/repository is where the companies standard stuff goes, and the local "in project" repo is where YOUR stuff goes.
This is not possible with the command line client but you can create more complex repository layouts with a Maven repository server like Nexus.
The reason why it's not possible is that Maven allows to nest projects and most of them will reference each other, so installing each artifact in a different repository would lead to lots of searches on your local hard disk (or to failed builds when you start a build in a sub-project).
FYI: symlinks work in Windows7 and above so this kind of thing is easy to achieve if all your code goes in the same place in the local repo, i.e /com/myco/.
type mklink for details
I can see that you do not want to use special versions or classifiers but that is one of the best solutions to solve this problem. I work on the same project but different versions and each mvn install takes half an hour to build. The best option is to change the pom version appended with the change name, for example 1.0.0-SNAPSHOT-change1 that I'm working on thereby having multiple versions of the same project but with different code base.
It has made my life very easy in the long run. It helps run multiple builds at the same time without issues. Even during SCM push, we can skip the pom file from staging so there can always be 2 versions for you to work on.
In case you have a huge project with multiple sub-modules and want to change all the versions together, you can use the below command to do just that
mvn versions:set -DnewVersion=1.0.0-SNAPSHOT-change1 -DprocessAllModules
And once done, you can revert using
mvn versions:revert
I know this might be not what you are looking for, but it might help someone who wants to do this.

Maven: local development deploy vs bundling for distribution

Bear with me, I'm migrating from Ant to Maven2: I think I've hit one of those little things that was easy in Ant, but not so in Maven...
How do I handle the difference between a local deployment vs. creating an archive/bundle for distribution to another machine?
Let's assume my project's output is an EAR plus some additional config files. A developer that is actively working on the project will need to deploy and re-deploy frequently to his local app-server (say JBoss), while an Integration Engineer that is building for QA/production will need only to create the final archive assembly (tar/gz).
In Ant we had two targets for this: "dev-deploy" and "bundle". Both do a complete build, but differ in the final step: "dev-deploy" copies the EAR and config files to the respective local folders, while "bundle" just puts the EAR & config files in a tar.gz assembly.
How do you do this in Maven?
I've seen that the assembly plugin can create either archives (tar, gz, etc.) or exploded directories (from the same assembly descriptor). I can invoke either assembly:assembly or assembly:directory, but for the latter, how do I copy the final output to the local JBoss deployment folders? From a related post it seems that ad-hoc copying of files is not really what Maven is about, so an antrun copy is probably the most appropriate?
Finally, since the type of assembly may differ depending on who invokes it, it doesn't seem wise to bind assembly to the build lifecycle, not so? But this means that a developer will always need to invoke 'mvn package' followed by 'mvn assembly:directory' to rebuild and test a change. Conversely, an Integration Engineer will always need to run 'mvn package' followed by 'mvn assembly:assembly' to create the distributable archive. I was hoping for a one-command solution for each, or should I just script it?
In Ant we had two targets for this: "dev-deploy" and "bundle". Both do a complete build, but differ in the final step: "dev-deploy" copies the EAR and config files to the respective local folders, while "bundle" just puts the EAR & config files in a tar.gz assembly.
Not sure what you mean by respective local folders about "dev-deploy" but this sounds like what mvn pacakge is doing and "bundle" indeed sounds like a maven assembly.
I've seen that the assembly plugin can create either archives (tar, gz, etc.) or exploded directories (from the same assembly descriptor). I can invoke either assembly:assembly or assembly:directory, but for the latter, how do I copy the final output to the local JBoss deployment folders? From a related post it seems that ad-hoc copying of files is not really what Maven is about, so an antrun copy is probably the most appropriate?
I guess that we are talking about the Integration Engineer's tasks here. As you didn't explain what the "bundle" contains exactly, what the target application server is (my understanding is that you are using JBoss for QA/production too but, again, this is a guess), if this bundle has to be deployed automatically, it's hard to imagine all solutions and/or alternatives to antrun. But indeed, to copy/move/unzip/whatever the assembly, the maven antrun plugin is a candidate.
Finally, since the type of assembly may differ depending on who invokes it, it doesn't seem wise to bind assembly to the build lifecycle, not so? But this means that a developer will always need to invoke 'mvn package' followed by 'mvn assembly:directory' to rebuild and test a change. Conversely, an Integration Engineer will always need to run 'mvn package' followed by 'mvn assembly:assembly' to create the distributable archive. I was hoping for a one-command solution for each, or should I just script it?
My understanding was that the Integration Engineer was building the bundle. Why would a developer need the bundle? This is confusing... Anyway, I don't really need the details to think of an answer. You could actually declare the maven assembly plugin into specific build profiles, one for development and one for integration, and bind either the single or the directory-single mojos to the project's build lifecycle in each profile. This would allow to use only one command and avoid any scripting (really, don't go this way).