When running mvn install on a local multi module project it builds and install the projects artifacts into the local repo. mvn clean seems to clean up my project specific target directories.
What command do I use with maven to get it to uninstall my projects modules from the local repo? for example my projects outputs foo-0.1.jar and bar-0.2.jar I want those removed from my local repo without having to go in there and delete them myself.
mvn build-helper:remove-project-artifact
You can purge artifacts from your local repository, but why do you like to do this? Apart from that you can do that via maven-dependency-plugin:
This will purge all project- and dependency artifacts
mvn dependency:purge-local-repository -DreResolve=false
This can be influenced by supplemental command line arguments (see the documentation) for further details.
Best is to implement a release strategy, i.e. as long as the artifacts under development appending the version with SNAPSHOT. Maven then automatically updates the artifacts in the local repository when you run install. Once you have completed the development you remove the SNAPSHOT and release the version (i.e. via deploy). If further development is required you could increase the version number and append it again with SNAPSHOT.
Related
Are both the things are doing the something different or not?
As the second one, when you right click on any maven project on eclipse go to Maven and then Update project.
First is pretty much clear that it clean and artifacts from target and generate the artifacts into target and local repository.
In the first case, you start Maven to build a jar/war/ear and install it in your local repository. It is Maven mechanism. It also updates your dependencies through the -U flag.
In the second case, you start a procedure of the m2eclipse plugin that updates you dependencies. It will not write any artifacts to your local repository. It also does not run a full build.
I am new to maven and I heard the term "maven clean repo" building ? What is the meaning of this ? How it different from the normal maven building process ? Also I want to know about the maven repository and how it changes when we build the software
I'm not sure if there is an exact term called "maven clean repo building" - but it is probably referring to doing a clean build by clearing out your entire LOCAL maven repository to ensure you have only the correct dependencies for your project.
All dependencies you need get downloaded into the repository which is at ${user.home}/.m2/repository by default. You can see this grows as the build runs and dependencies get downloaded into this folder.
The link
http://maven.apache.org/plugins/maven-dependency-plugin/examples/purging-local-repository.html explains one way of purging this.
You can change the maven repo being used for the build by providing the following argument to the build command
mvn clean install -Dmaven.repo.local=/tmp/sampleRepo
If relevant artifacts are not available in the pointed maven repo, it will download them from relevant repositories (maven central or repositories which are provided in the pom.xml file).
Hint;) Using a directory in /tmp/ will be more good as /tmp/ get automatically cleared in OS restart.
I am in a situation where I have one Build Server box which is to carry out all continuous integration and manage our maven repository. The box works as follows:
There is one maven repository which is hosted through Apache Server as a URL for developers to use
All Jenkins jobs (including release jobs) run mvn install so that artifacts are kept in this one repository.
I would like to get rid of the Apache server and run Nexus on this same box to manage and host repositories, however I have the following questions/ideas:
With Nexus and Jenkins on the same box, will it mean that I will have to manage two repositories, one where maven installs an artifact to a local repository, and one where maven deploys an artifact to nexus? Would it be possible to have Nexus manage the "mvn install" repository also? How can I make sure we don't run out of disk space on the server very very quickly all the time?
Thanks
Added as response to comments: Thank you both, I am thinking I will just set the Jenkins jobs and release plugin goals to mvn package deploy:deploy in order to skip the install phase, that way, artifacts go directly from the target directory to Nexus. However I guess the Jenkins job will require a local repository from which to use depedencies which will get copied from Nexus to the maven local repository during the build, I am not sure if this can be avoided though.
mvn install installs in the local repository
mvn deploy installs to the remote repository
these semantics are defined in the lifecycle and map to different plugins. Their implementations are different.
You don't have to manage the local repository. Actually for some if not most jobs you might even want to define it localized to the job (with the 'Use private Maven repository' option) instead of to the user who is running the job, especially that you plan to use nexus for repository.
You will have to change your jobs to use mvn deploy instead.
How can I make sure we don't run out of disk space on the server very
very quickly all the time?
Configure Jenkins/Nexus. Discard old builds and disable automatic artifact archiving. Both settings can be found in the Jenkins job-configuration. Also you could delete old artifacts automatically from Nexus using Scheduling Tasks.
There is no need to install the artifacts into the local maven repository when using Jenkins/Nexus on a dedicated server.
My situation: I have project which contains several Maven modules. I make changes to one of them. Suddenly I find out, that my project is no longer possible to be built because of the errors in other modules. To fix this I need to run SVN UPDATE and rebuilt the project.
My assumption: probably, during the build process of my module some of the artifacts are taken from central repository and have the most newest version, while others are still outdated and taken from my local repo.
A question: I don't want to rebuild my project each time someone updates ANOTHER Maven module. I want to download the already built artefacts from the central repository without rebuilding them by myself. Is it possible?
You can tell Reactor which modules to build. In your case when you only change a single module and want to speed up the build you can pass -pl (Project Location) parameter to maven. For example:
mvn -pl module-with-changes
That will build single module, while taking other dependencies from your local Maven Repository or download from Central (whatever is the latest). That said, if you already ran mvn install for whole project and other artifacts have not been updated in Central repository, then Maven will see your local artifacts as latest and will not re-download them.
Another issue you might get with -pl parameter is when other modules in your project depend on the module that you are building. If there is a problem in dependent module you will not see it by building only the dependency model. To avoid that you can pass -amd (Also Make Dependents). Like this:
mvn -pl module-with-changes -amd
That will trigger the build for module-with-changes + modules that depend on module-with-changes + their dependents.
You can get more info about Reactor parameters from here:
http://www.sonatype.com/people/2009/10/maven-tips-and-tricks-advanced-reactor-options/
We use mvn deploy:deploy to deploy an artifact to repository manager and a developer could have done just mvn install for the same artifact, so the artifact is present under M2_HOME\.m2\repository
Will the maven runtime retrieve the artifact from the repository manager if it was updated recently than the local repository copy?
Note: We use a maven repository manager based on Apache Archiva.
The answer depends on whether you're talking about a snapshot or a release build.
Release builds have a version that doesn't end with "-SNAPSHOT", and they're final and immutable. Once installed to any repository, Maven will never update them. To your question, that means that if a dev installs a release build locally, it will never be updated from any remote repository.
Snapshot builds are always eligible to be updated from any repository. By default, Maven checks once per day for new snapshot versions, so if someone installs a snapshot locally, that snapshot will exist until Maven does its next check for snapshot updates. Then, if a newer version is in any remote repository it checks, the local one will be overwritten. You can force maven to update snapshot artifacts with the -U command line option.