Maven Release to Nexus – Maven发布到Nexus

最后修改: 2013年 5月 7日

1. Overview


In the previous article of this series, we set up a deployment process with Maven to Nexus. In this article, we’ll configure the Release Process with Maven – both in the pom of the project as well as in a Jenkins job.


2. Repository in the pom


In order for Maven to be able to release to a Nexus Repository Server, we need to define the repository information via the distributionManagement element:



The hosted Releases Repository comes out of the box on Nexus, so there is no need to create it explicitly.


3. SCM in the Maven pom

3.Maven pom中的SCM

The Release process will interact with the Source Control of the project – this means we first need to define the <scm> element in our pom.xml:



Or, using the git protocol:



4. The Release Plugin


The standard Maven plugin used by a Release Process is the maven-release-plugin – the configuration for this plugin is minimal:



What is important here is that the releaseProfiles configuration will actually force a Maven profile – the releases profile – to become active during the Release process.


It is in this process that the nexus-staging-maven-plugin is used to perform a deploy to the nexus-releases Nexus repository:

在这个过程中,nexus-staging-maven-plugin被用来向nexus-releases Nexus仓库进行部署。


The plugin is configured to perform the Release process without the staging mechanism, same as previously, for the Deployment process (skipStaging=true).


And also similar to the Deployment process, Releasing to Nexus is a secured operation – so we’re going to use the Out of the Box deployment user form Nexus again.

而且与部署过程类似,释放到Nexus是一个安全的操作–所以我们要再次使用Out of the Box deployment用户表单Nexus。

We also need to configure the credentials for the nexus-releases server in the global settings.xml (%USER_HOME%/.m2/settings.xml):



This is the full configuration


5. The Release Process


Let’s break apart the release process into small and focused steps. We are performing a Release when the current version of the project is a SNAPSHOT version – say 0.1-SNAPSHOT.


5.1. Release:Clean


Cleaning a Release will:


  • delete the release descriptor (
  • delete any backup POM files

5.2. release:prepare


Next part of the Release process is Preparing the Release; this will:


  • perform some checks – there should be no uncommitted changes and the project should depend on no SNAPSHOT dependencies
  • change the version of the project in the pom file to a full release number (remove SNAPSHOT suffix) – in our example – 0.1
  • run the project test suites
  • commit and push the changes
  • create the tag out of this non-SNAPSHOT versioned code
  • increase the version of the project in the pom – in our example – 0.2-SNAPSHOT
  • commit and push the changes

5.3. release:perform


The latter part of the Release process is Performing the Release; this will:


  • checkout release tag from SCM
  • build and deploy released code

This second step of the process relies on the output of the Prepare step – the

这个过程的第二步依赖于 “准备 “步骤的输出–

6. On Jenkins


Jenkins can perform the release process in one of two ways – it can either use it’s own release plugins, or it can simply run perform the release with a standard maven job running the correct release steps.


The existing Jenkins plugins focused on the release process are:


However, since the Maven command for performing the release is simple enough, we can simply define a standard Jenkins job to perform the operation – no plugins necessary.


So, for a new Jenkins job (Build a maven2/3 project) – we”ll define 2 String parameters: releaseVersion=0.1 and developmentVersion=0.2-SNAPSHOT.


At the Build configuration section, we can simply configure the following Maven command to run:


Release:Clean release:prepare release:perform 
   -DreleaseVersion=${releaseVersion} -DdevelopmentVersion=${developmentVersion}

When running a parametrized job, Jenkins will prompt the user to specify values for these parameters – so each time we run the job we need to fill in the right values for releaseVersion and developmentVersion.


Also, it’s worth using the Workspace Cleanup Plugin and check the Delete workspace before build starts option for this build. However keep in mind that the perform step of the Release should necessarily be run by the same command as the preparestep – this is because the latter perform step will use the file created by prepare. This means that we cannot have a Jenkins Job running prepare and another running perform.

此外,值得使用Workspace Cleanup Plugin,并为该构建勾选Delete workspace before build starts选项。但是请记住,Release的perform步骤必须由prepare步骤的同一命令运行–这是因为后者的perform步骤将使用由prepare创建的>文件。这意味着我们不能让一个Jenkins作业运行prepare和另一个运行perform

7. Conclusion


This article showed how to implement the process of Releasing a Maven project with or without Jenkins. Similar to Deployment, this process is using the nexus-staging-maven-plugin to interact with Nexus and focuses on a git project.