A simple command line to download a remote maven2 artifact to the local repository

maven-2

I have a library that I distribute using maven 2. The typical user of this library doesn't use maven to build their applications, but is likely somewhat familiar with maven and probably has it installed.

I'd like to document a "simple" one line command they can use to download my library's artifacts to their local ~/.m2/repository without requiring that they set up a pom.xml to do it.

I thought there was a way to do this, but I can't seem to find it after looking through the install:install-file and dependency plugin documentation. I tried things like:

mvn install:install-file -DrepositoryId=java.net -Durl=http://download.java.net/maven/2/ -Dfile=robo-guice-0.4-20091121.174618-1.jar -DpomFile=robo-guice-0.4-20091121.174618-1.pom -DgroupId=robo-guice -DartifactId=robo-guice -Dversion=0.4-SNAPSHOT -Dpackaging=jar

but I think I'm barking up the wrong tree since it appears that the install plugin is used to copy locally built files into the local repository, rather than download remote artifacts into the local repository.

This is the artifact I'd like to install: http://download.java.net/maven/2/robo-guice/robo-guice/0.4-SNAPSHOT/

Is this possible using maven?

Best Answer

Since version 2.1 of the Maven Dependency Plugin, there is a dependency:get goal for this purpose. To make sure you are using the right version of the plugin, you'll need to use the "fully qualified name":

mvn org.apache.maven.plugins:maven-dependency-plugin:2.1:get \
    -DrepoUrl=http://download.java.net/maven/2/ \
    -Dartifact=robo-guice:robo-guice:0.4-SNAPSHOT

Related Solutions

How to manually install a jar to the local Maven repository

The command you are using is OK. I just copied and pasted it and successfully installed the same freshly downloaded jar in my local repository:

pascal@laptop:~/Downloads$ mvn install:install-file -Dfile=gxp-0.2.4-beta.jar -DgroupId=com.google -DartifactId=gxp -Dversion=0.2.4-BETA -Dpackaging=jar
[INFO] Scanning for projects...
[INFO] Searching repository for plugin with prefix: 'install'.
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Default Project
[INFO]    task-segment: [install:install-file] (aggregator-style)
[INFO] ------------------------------------------------------------------------
[INFO] [install:install-file {execution: default-cli}]
[INFO] Installing /home/pascal/Downloads/gxp-0.2.4-beta.jar to /home/pascal/.m2/repository/com/google/gxp/0.2.4-BETA/gxp-0.2.4-BETA.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2 seconds
[INFO] Finished at: Wed Dec 09 08:44:37 CET 2009
[INFO] Final Memory: 3M/53M
[INFO] ------------------------------------------------------------------------

So you must have a problem with the maven-install-plugin plugin (maybe corrupted after an incomplete download). Delete ~/.m2/repository/org/apache/maven/plugins/maven-install-plugin (or even more stuff under ~/.m2/repository/org/apache/maven) and try again.

Java – Maven is failing to download the tomcat-maven-plugin snapshot

I rechecked and, with the following pom fragments:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  ...
  <pluginRepositories>
    <pluginRepository>
      <id>Codehaus Snapshots</id>
      <url>http://snapshots.repository.codehaus.org/</url>
      <snapshots>
        <enabled>true</enabled>
      </snapshots>
      <releases>
        <enabled>true</enabled>  <!-- Workaround for MNG-2974, see note below -->
      </releases>
    </pluginRepository>
  </pluginRepositories>
  ...
  <build>
    <finalName>my-webapp</finalName>
    <plugins>
      ...
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>tomcat-maven-plugin</artifactId>
        <version>1.0-SNAPSHOT</version>
      </plugin>
      ...
    </plugins>
   ...
  </build>
</project>

The SNAPSHOT of the plugin has been downloaded successfully:

$ mvn clean
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Building my-webapp Maven Webapp
[INFO]    task-segment: [clean]
[INFO] ------------------------------------------------------------------------
[INFO] snapshot org.codehaus.mojo:tomcat-maven-plugin:1.0-SNAPSHOT: checking for updates from Codehaus Snapshots
[INFO] snapshot org.codehaus.mojo:tomcat-maven-plugin:1.0-SNAPSHOT: checking for updates from maven2-repository.dev.java.net
Downloading: http://snapshots.repository.codehaus.org//org/codehaus/mojo/tomcat-maven-plugin/1.0-SNAPSHOT/tomcat-maven-plugin-1.0-20091222.232027-11.pom
5K downloaded  (tomcat-maven-plugin-1.0-20091222.232027-11.pom)
Downloading: http://snapshots.repository.codehaus.org//org/codehaus/mojo/tomcat-maven-plugin/1.0-SNAPSHOT/tomcat-maven-plugin-1.0-20091222.232027-11.jar
48K downloaded  (tomcat-maven-plugin-1.0-20091222.232027-11.jar)
[INFO] [clean:clean {execution: default-clean}]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 9 seconds
[INFO] Finished at: Wed Jan 06 16:13:28 CET 2010
[INFO] Final Memory: 7M/78M
[INFO] ------------------------------------------------------------------------

It's very weird because I can't see any difference, but things are working as expected. In other words, I can't reproduce...

In your local repository, do you have maven-metadata*.xml files in the 1.0-SNAPSHOT directory for the tomcat-maven-plugin artifact? Do they match the ones on the remote server? Do they correctly specify the build number and timestamp?

If they are incorrect locally, running maven with -U might help.

You might also check mvn help:effective-pom and see what Maven thinks the updatePolicy is for snapshots on that repository.

Or maybe just delete your tomcat-maven-plugin artifact from your local repository and try again.

If nothing helps, try to install it manually (download the plugin from the repository and use the mvn install:install-file mojo) or checkout the sources from the VCS and build it locally. But these options are just workarounds, you have a problem somewhere (what version of maven are you using?).

Best Answer

Related Solutions

How to manually install a jar to the local Maven repository

Java – Maven is failing to download the tomcat-maven-plugin snapshot

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