Develop Reference

Git flow: How to configure a one-click release process in Jenkins?

We are using the standard git flow branching model (develop, master, release-, hotfix-, etc).
As part of our workflow, we would like to set up a "one-click" release via jenkins.
I was looking at the jgitflow-maven-plugin. Can I set up this plugin to do a one-click release from jenkins? If so, what are the configuration options?
In particular, can I do something like this?
Jenkins Job
Maven goals: release-start release-finish -Dsomething -Delse
And is there a way tell it to automatically build from the latest -SNAPSHOT version, e.g. if the version is 1.2.3-SNAPSHOT it would build release-1.2.3.
Otherwise, is there a maven plugin that builds releases according the git flow branching model (i.e. build from develop and create a new release branch named release-x.y.z).

Although this answer is one year old I'd like point out that meanwhile the jgitflow (v1.0-m5.1) works with maven batch mode.
So to release an artifact with just one command you can execute:
mvn --batch-mode jgitflow:release-start jgitflow:release-finish
You don't need to set developmentVersion and releaseVersion.
JGitFlow will use the current version minus the -SNAPSHOT part as release version. Then it increments the least significant digit and adds -SNAPSHOT again for the next development version.
Example 1.0.0-SNAPSHOT --> Release: 1.0.0, next Development version: 1.0.1-SNAPSHOT
In order to configure a single click Jenkins release job you need to configure some things regarding Git.
Under Source Code Management > Git > Additional Behaviors select
Wipe out repository & force git clone: just to make sure the workspace is clean
Checkout to specific local branch: your develop branch.
Finally, the release happens locally on your Jenkins server, so you want to push back the changes to your Git remote server.
To accomplish this, the easiest way is to add a Post-build action which executes the following bash command (the branch names may vary, I've used the JGitFlow default values):
git push origin develop master --tags
Note If Jenkins is running on Windows you either have to execute a Batch script containing the same command (sometimes this doesn't work due to SSH issues with Windows) or configure the Git Publisher Post-build action accordingly.

You can simply use the jenkins plugin M2 Release Plugin with the release goals an options
-B -DautoVersionSubmodules=true jgitflow:release-start jgitflow:release-finish

We ended up with starting the release via CLI on the client (because in Jenkins there is a bug starting the release).
git flow release start -DautoVersionSubmodules=true
If you want to use the batch mode you need to specify developmentVersion and releaseVersion.
Created a new job in Jenkins to build the release branch and use the M2 Release Plugin to release it finally:
-B jgitflow:release-finish
If you use some custom profiles, you have to pass them additional via arguments caused by a bug.
-Darguments=-Pprofile

We never found a way to get this to work via a plugin or maven goal in Jenkins.
Our solution ended up with a bash script that did git flow release start <version>, maven release process, git flow release finish <version> and other things (git pull on develop and master at very start, git push and slack notification at very end).

Sandboxed Maven builds on Jenkins

I am trying to find a solution for the following puzzle. I have java projects, managed by maven, which needs some native dependencies to work (run unit and integration tests). Those are provided in form of deb packages, which needs to be installed prior to running a build.
I use Jenkins for CI. Native dependencies can not be installed on Jenkins nodes, because of conflicts with other builds and they can change often. What I do now is not to create a Jenkins job type 'maven', but 'freestyle' and use a pbuilder to create an clean sandbox, install all that is necessary and invoke maven build.
This is working great, but I am loosing Jenkins maven goodies like automatic upstream projects, trigger build when dependency change, etc. Jenkins simply does not know that maven is there.
Finally, my question. Is there a way how to achieve both, isolate build so installed libraries does not affect other builds and leverage Jenkins's 'magic' applied to maven builds and their dependencies?

You could split your build in three jobs, which trigger the next one.
Create needed environment
Run maven job
Clean Up

Even a Freestyle job has "Invoke top-level Maven targets". You could use that to get "maven goodies" while also having ability to run other build steps.
There is an option to "use private Maven repository" which will make sure it will use the .m2/repository folder location relative to the workspace. If you need to separate into multiple jobs, you can use "Custom/shared workspace" between those jobs.
Even in Maven-style job, there is an option to use private repository, so that one job does not affect another.

The problem can be solved by using distributed Jenkins builds. Slave agents can be configured to provision clean environment (e.g. via VMs, docker,...) for each build and tear it down after build is done. This way Jenkins job can be of Maven type and any changes done by pre-build step will not affect others.
More information can be found here.

Consider docker. There you can run processes in isolated environments just as you want. Docker works in a way that it easily communicates with Jenkins.
As a benefit you can also use that docker container to run local builds in the same environment as they run in Jenkins.

Using maven-release-plugin in Eclipse

I recently tried to use maven-release-plugin since it is apparently the recommended way of building and packages releases in the Maven universe.
However I wanted to use this within Eclipse, as the rest of my development workflow is Eclipse based. I normally run Maven commands via the m2eclipse plugin provided as part of Eclipse Juno (4.2)
I noticed a few oddities when I tried to run "release:prepare" within Eclipse:
Some extra files were created in the root project directory - "pom.xml.releaseBackup" and "release.properties". Do they really belong there? Have I got the release directories set up correctly? I wouldn't really consider these temporary artifacts as part of my source code tree......
The pom.xml gets manually overwritten with the updated release number. Eclipse warns you and is happy to reload the updated version - but is this generally safe?
The prepare ultimately fails giving the error [ERROR] Failed to execute goal org.apache.maven.plugins:maven-release-plugin:2.0:prepare (default-cli) on project clisk: Failed to invoke Maven build. Error configuring command-line. Reason: Maven executable not found at: C:\Users\Mike\git\clisk\EMBEDDED\bin\mvn.bat -> [Help 1] - presumably because I am using the built-in Maven excetable provided by m2eclipse rather than the command line. I guess I could install command line maven as well.... but is that sensible or will it just cause more problems?
Given these kind of issues, Is there a way to get maven-release-plugin to work smoothly within Eclipse, or should I just give up and continue to do releases manually?

I have been using release plugin, but only from command line.
Re. 1. The backup files that release plugin creates are needed if something goes wrong in time of preparing the release. You can always rollback the prepared release using release:rollback command. When you do release:perform they will be deleted.
Re. 2. The plugin changes the version number from snapshot version for example: 0.0.1-SNAPSHOT: to release version: 0.0.1. Then after release:perform release version is moved to the maven repository and release plugin changes version again to 0.0.2-SNAPSHOT. Now you can use you full released (tested) version in your testing or production enviornment and snapshot version for developping purposes.
Re. 3. I don't know what is causing the problem, but I don't see the problem by using release plugin from command line.

Also mvn 3.3.3 installs a mvn.cmd file, instead of a mvn.bat file in Windows.
You should copy mvn.cmd to mvn.bat

Well i know this link is OLD , but to help some on who reffers this link for the issue 3.
Install maven separately on to local Box and give the path of the installation under Windows->Preferences--> maven--> Installation. Also you have to define the same in the run configuration within the Eclipse.
Attached is a link that explains the same.
http://maven.40175.n5.nabble.com/Build-Failure-prepare-release-td510949.html

You might be able to overcome the error you mention by installing command line Maven and configure Eclipse to use that rather than the embedded one by choosing Window -> Preferences -> Maven -> Installations, but I agree with the advice of making your releases outside Eclipse.

Maven release use parts

Maven release plugin is a cool tool which simplifies releasing. But I want to change the behavior a little bit.
Most important I do not want any changes to be commited to the repository automatically. This should be done by developers manually.
I am dreaming of something like:
checking that no SNAPSHOT dependency is used (must)
checking that there are no uncommited changes (optional)
updating version numbers of all artifacts, allow user to enter new version number (must)
solved: with with mvn versions:set
build project locally
solved: with mvn clean install
I do not know how to cherry-pick some of the methods which do the work in release-plugin. Any ideas?

The things you described will be automatically be done by the maven-release-plugin. If you don't have svn installed on the build server you need to configure the release plugin to use the svnkit installation

Eclipse won't believe I have Maven 2.2.1

I have a project (built from an AppFuse template) that requires Maven 2.2.1. So I upgraded to this (from 2.1.0) and set my path and my M2_HOME and MAVEN_HOME env variables.
Then I ran mvn eclipse:eclipseand imported the project into Eclipse (Galileo).
However, in the problems list for the project (and at the top of the pom.xml GUI editor) it says:
Unable to build project
'/export/people/clegg/data/Workspace/funcserve/pom.xml;
it requires Maven version 2.2.1
This persists whether I set Eclipse to use its Embedded Maven implementation, or the external 2.2.1 installation, in the Preferences -> Maven -> Installations dialog.
I've tried closing and reopening the project, reindexing the repository, cleaning the project, restarting the IDE, logging out and back in again, everything I can think of! But Eclipse still won't believe I have Maven 2.2.1.
I just did a plugin update so I have the latest version of Maven Integration for Eclipse -- 0.9.8.200905041414.
Does anyone know how to convince Eclipse I really do have the right version of Maven? It's like it's recorded the previous version somewhere else and won't pay any attention to my changes :-(

Eclipse allows you to specify an external Maven installation. But there's a catch. :(
Have a look at Windows > Preferences > Maven > Installations.
You will see a message like this:
Note: Embedded runtime is always used for dependency resolution, but does
not use global settings when it is used to launch Maven.
To learn more, visit the maven web page.
Translating to English, it means that Eclipse will continue to employ its internal Maven instance in order to perform some tasks.
When you "Run As > maven install" it will run your pom.xml script employing the external Maven instance you specified but when Eclipse performs some of its internal stuff, it will continue to use the embedded Maven instance, whatever version it is.
(edited)
As far as I know, when you install M2Eclipse you are implicitly defining which "internal Maven instance" you will have, which is exactly that one packaged by the plugin.
In the plugin configuration, you can add external Maven instances by telling where they are installed.

If you are using a recent m2eclipse version, you can try this too:
<prerequisites>
<maven>>=2.2.1</maven>
</prerequisites>
Notice the greater than in >=2.2.1. It works fine for me.

A common source of trouble (of this kind) is if you change global preferences and don't remember or know that you have enabled some project specific settings. At least it's a chance that the global setting is now set to use the external maven but the project setting is still set to 'embedded'.

M2Eclipse uses an embedded maven instance, not the maven instance you have installed on your system.

Have you tried switching workspaces?
You can still reference the same project in the new workspace. This would provide about as much of a reset as you can do in terms of eclipses internal settings.

Try creating your eclipse project with mvn project:m2eclipse or use the maven import option under import project.

Using m2eclipse, my fallback in these situations is to do Maven > Update Dependencies and then Maven > Update Project Configuration. The first is just me being supersticious, but the second will rewrite .project and .classpath.
As Pascal says about, m2eclipse can also be pointed at an external instance. I've done this in the past, though not at 2.2.1.
Dan

I got the same issue. Resolved it by restarting the system because every time you change the 'Path' in environment variables you should restart the system or else if would not pick the changes.