I have a Maven plugin which is a year or two old. Recently I noticed that the helpmojo goal of maven-plugin-plugin appears to not be working.
It is working for an older version of the plugin - I'm not sure at which release it stopped working.
By "not working" I mean that the help goal is not correctly generated and is not found when called using mvn <plugin>:help, whilst other goals are found.
HelpMojo.java is created under target/generated-sources/plugin, but no entry appears in the the plugin descriptor, plugin.xml in the final .jar.
Has a bug or breaking change been introduced in a recent version of maven-plugin-plugin or have I changed something which has prevented it from working as a side-effect? (For example, the plugin project is now multi-module.)
The pom.xml config looks like this:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-plugin-plugin</artifactId>
<version>3.2</version>
<executions>
<execution>
<id>generated-helpmojo</id>
<goals>
<goal>helpmojo</goal>
</goals>
</execution>
</executions>
</plugin>
The fix was to downgrade to version 3.1
Related
I created a simple web scraper with Java and Selenium. It just reads a single piece of information and writes that to a CSV file.
I'm trying to run it daily using some scheduler on Heroku. The official Heroku documentation says I need to add this to the pom.xml:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>3.0.1</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>package</phase>
<goals><goal>copy-dependencies</goal></goals>
</execution>
</executions>
</plugin>
But when I add it to the pom.xml, I'll get
Plugin 'org.apache.maven.plugins:maven-dependency-plugin:3.0.1' not found
even though it found in mvnrepository.com. What is happening here?
First of all, run the build again (with something like mvn clean verify) and see if you get the error again.
If so, you probably have a network/firewall issue, or you misconfigured your settings.xml (if you have one).
I managed to build a Maven project in a way that makes the release deploy artifacts either double or not at all.
Since the project uses an abstract parent pom of our company it's a bit hard to post the relevant code, but I'll try.
First things first. The parent pom has the following definition:
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
<configuration>
<deployAtEnd>true</deployAtEnd>
</configuration>
</plugin>
With nothing defined in the actual project, the release will fail after these lines:
[INFO] [INFO] Uploaded to our_repo: http://acme.org/nexus/content/repositories/org.acme.project/1.0.0/org.acme.project-1.0.0-sources.jar (14 kB at 3.8 kB/s)
[INFO] [INFO] Uploading to our_repo: http://acme.org/nexus/content/repositories/org.acme.project/1.0.0/org.acme.project-1.0.0-sources.jar
Our repo doesn't like having two release JARs with the same version, so everything fails. The weird part here is that the deployment is NOT at the end. In fact the project build fails halfway through.
However if I copy the above plug-in in the project, the build will print Deploying repo:org.acme.repo:1.0.0 at end at the same position and then not deploy anothing at the end.
But I'm not even sure that's part of the problem. Still I think both builds should work exactly the same no matter where the plug-in definition is.
I found this question, which made me check the maven-source-plugin in the effective pom. However there are no duplicates there:
<plugin>
<artifactId>maven-source-plugin</artifactId>
<version>3.0.1</version>
<executions>
<execution>
<id>attach-sources</id>
<goals>
<goal>jar-no-fork</goal>
</goals>
<configuration>...</configuration>
</execution>
</executions>
</plugin>
Nothing is defined in the maven-assembly-plugin either, so no JAR is added for deployment (suggested in this question).
It might have to do with us using Java 10 or Maven 3.5.2, though I'm honestly stumped on what to test and where to progress.
How do I fix this mess? (If you'd like more information about the build, just ask. The pom.xml is way to big to share them here.)
Inspired by that question I tried to disable the release profile, and now it works somehow. I'm not able to conjure any kind of explanation for that behavior.
Snippet for removing the release profile:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-release-plugin</artifactId>
<configuration>
<useReleaseProfile>false</useReleaseProfile>
</configuration>
</plugin>
Is it possible to specify in a POM the minimum version of Maven required to build the project?
We've been wasting lots of time chasing issues from people building our project due to bugs in older versions of Maven that cause large artifacts (>2GB) to be silently truncated. These tend to cause, unsurprisingly, strange and broken behavior in the final product.
Yes, we have stated that 3.2.5 is the minimum version we intend to support, but I'm wondering: Is there a way to ask Maven to bail if the version is less than that? I reckon I can easily write a plugin to do this, but that seems overkill. So, I was hoping there is a simpler way.
You can use the maven-enforcer-plugin and its enforce goal to specify a minimum required Maven version:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-enforcer-plugin</artifactId>
<version>1.4.1</version>
<executions>
<execution>
<id>enforce-maven</id>
<goals>
<goal>enforce</goal>
</goals>
<configuration>
<rules>
<requireMavenVersion>
<version>3.2.5</version>
</requireMavenVersion>
</rules>
</configuration>
</execution>
</executions>
</plugin>
If someone tries to build the project with a Maven version less than 3.2.5, the build will fail.
You can enforce a lot of different rules with this plugin (Java version, OS...); see the complete list on the plugin documentation.
If you only need the maven version the prerequisites should already do the job:
see: https://maven.apache.org/pom.html#Prerequisites
Anything more than that will require the enforcer plugin (see other answer).
I'm trying to write a Maven plugin, following the documentation. When I try to build I get:
[ERROR] Failed to execute goal
org.apache.maven.plugins:maven-plugin-plugin:2.9:descriptor
(default-descriptor) on project cmake-dependency-plugin: Error
extracting plugin descriptor: 'No mojo definitions were found for
plugin: com.iar:cmake-dependency-plugin.' -> [Help 1]
Google points me to this Jira issue, which, if I read it correctly means that annotations do not work in maven unless a rather cumbersome workaround is employed (which, by the way, did not work for me).
What bothers me more is that it seems to be closed due to some form of Jira-bankruptcy executed by the Maven developers where a bunch of Jira issues have been summarily closed. Since this seems like the primary way to write Maven plugins, I would think that this would be pretty important, but I'm obviously missing something.
Am I misinterpreting the issue, or are maven annotations really broken?
EDIT: This seems to refer to the same problem, but I would be interested to know more details about why such a seemingly central feature can be left broken like this. Aren't Maven annotations used by Maven plugin developers?
First you are using an old maven-plugin-plugin version 2.9 from 2011...I assume you are working with Maven 3.X and so i would recommend to use an up-to-date version like 3.2. and follow the steps described in the JIRA issue.
Furthermore i would recommend to read the documentation about maven-plugin-plugin where clearly stated that starting with version 3.0 you can use annotations.
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-plugin-plugin</artifactId>
<configuration>
<goalPrefix>XYZ</goalPrefix>
</configuration>
<executions>
<execution>
<id>default-descriptor</id>
<goals>
<goal>descriptor</goal>
</goals>
<phase>process-classes</phase>
</execution>
<execution>
<id>help-descriptor</id>
<goals>
<goal>helpmojo</goal>
</goals>
<phase>process-classes</phase>
</execution>
</executions>
</plugin>
My pom contains a version number following a sequence similar to 2.0-SNAPSHOT, at the same time we build the project with a manifest file, that needs parts of that version number since other projects are dependent on the specific version, however to simplify parts of the development we use 2.0 as the implementation version, so we dont have to switch between 2.0-SNAPSHOT and 2.0 in our dependency setup i would like to know if its possible to exclude the -SNAPSHOT from the ${project.version} so we dont have to maintain a variable manually?
For such purposes the build-helper-maven-plugin is the right one like this:
<project>
...
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>build-helper-maven-plugin</artifactId>
<version>1.8</version>
<executions>
<execution>
<id>parse-version</id>
<goals>
<goal>parse-version</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
...
</project>
It will provide the following properties:
parsedVersion.majorVersion
parsedVersion.minorVersion
parsedVersion.incrementalVersion
parsedVersion.qualifier
parsedVersion.buildNumber
Apart from that it sounds strange that you need the 2.0 as a released version where you don't have released the artifact yet. So you should think about using the maven-release-plugin to release artifacts which will change the version for your current project a like.