Question

I’m trying to have a Project B pull down (and unpack) a ZIP built by Project A and deployed to a remote repository.

The ZIP is created and attached using the maven-assembly-plugin, with packaging type pom:

<artifactId>project-a</artifactId>
<name>ZIP</name>
<description>Used by Project B</description>
<packaging>pom</packaging>

...

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-assembly-plugin</artifactId>
  <executions>
    <execution>
      <id>distribution-package</id>
      <phase>package</phase>
      <goals>
        <goal>single</goal>
      </goals>
      <configuration>
        <descriptors>
          <descriptor>src/main/assembly/scripts.xml</descriptor>
        </descriptors>
        <tarLongFileMode>gnu</tarLongFileMode>
      </configuration>
    </execution>
  </executions>
</plugin>

Attempting to pull it down from Project B‘s pom with the maven-dependency-plugin:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-dependency-plugin</artifactId>
  <executions>
    <execution>
      <id>copy-scripts</id>
      <phase>package</phase>
      <goals>
        <goal>copy</goal>
      </goals>
      <configuration>
        <outputDirectory>${basedir}/target/staging</outputDirectory>
        <stripVersion>true</stripVersion>
        <artifactItems>
          <artifactItem>
            <groupId>...</groupId>
            <artifactId>...</artifactId>
            <version>...</version>
            <overWrite>true</overWrite>
            <type>zip</type>
          </artifactItem>
        </artifactItems>
      </configuration>
    </execution>
  </executions>
</plugin>

fails with: [ERROR] Failed to execute goal on project ...: Could not resolve dependencies for project group:artifact:pom:version: Could not find artifact group:project-a:zip:version in nexus (http://...:8081/nexus/content/groups/public) -> [Help 1]

I would assume this is because I specified Project A‘s packaging as pom and not zip, however I can’t specify Project A as packaging type zip because it results in:

[ERROR]     Unknown packaging: zip @ line 13, column 13

Am I doing something wrong here or is this simply not possible?
I just have a bunch of files that I want to bundle up into an artifact and allow multiple other projects to download and unpack them for use. Open to different suggestions…

I’ve also checked to make sure that the assembled zip is indeed in the nexus.

UPDATED WITH ANSWER

For anyone else’s benefit, what I was missing is that the <classifier> of the dependency has to match the <id> of the assembly. Notice where thisistheattachedartifactsclassifier is specified in the following files.

scripts.xml (Project A):

<assembly>
  <id>thisistheattachedartifactsclassifier</id>
  <formats>
    <format>zip</format>
  </formats>

  <fileSets>
    <fileSet>
      <directory>src/main/resources</directory>
      ...
    </fileSet>
  </fileSets>
</assembly>

pom.xml (Project B):

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-dependency-plugin</artifactId>
  <executions>
    <execution>
      <id>copy-scripts</id>
      <phase>package</phase>
      <goals>
        <goal>copy</goal>
      </goals>
      <configuration>
        <outputDirectory>${basedir}/target/staging</outputDirectory>
        <stripVersion>true</stripVersion>
        <artifactItems>
          <artifactItem>
            <groupId>...</groupId>
            <artifactId>...</artifactId>
            <version>...</version>
            <classifier>thisistheattachedartifactsclassifier</classifier>
            <overWrite>true</overWrite>
            <type>zip</type>
          </artifactItem>
        </artifactItems>
      </configuration>
    </execution>
  </executions>
</plugin>

Answer 1

Welcome to Stack Overflow :).

You are on the right way. Your real problem is using a zip.

The following configuration is ok and work great for me. It’s an old one (2 years ago), and I’m not sure that match the best practices. But I Know that’s working.

This allow me to share some resources between projects, especially for unit tests.

Zip Project :

pom.xml

<groupId>com.mycompany</groupId>
<artifactId>cfg_dev</artifactId>
<version>1.1.0</version>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-assembly-plugin</artifactId>
            <executions>
                <execution>
                    <id>cfg-main-resources</id>
                    <goals>
                        <goal>single</goal>
                    </goals>
                    <phase>package</phase>
                    <configuration>
                        <descriptors>
                            <descriptor>/src/main/assembly/resources.xml</descriptor>
                        </descriptors>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

Assembly descriptor :
It will produce this artifact : cfg_dev-1.1.0-resources.zip
Please, note that

1. this is a zip archive

2. the “classifier” is resources (like assembly name)

   resources

   zip

   false

   src/main/resources

Main Project :

pom.xml

Please, note that

1. this depends on a zip archive

2. the dependency “classifier” is resources (like previous assembly name)

   <!-- Unit test dependency -->
   <dependency>
       <groupId>com.mycompany</groupId>
       <artifactId>cfg_dev</artifactId>
       <version>${project.version}</version>
       <classifier>resources</classifier>
       <type>zip</type>
       <scope>test</scope>
   </dependency>
   
     ....
   
   <build>
     <testResources>
       <!-- Ressources habituelles  -->
       <testResource>
           <directory>src/test/resources</directory>
           <filtering>true</filtering>
       </testResource>
       <!-- Unzipped resources from cfg_dev  -->
       <testResource>
           <directory>${project.build.directory}/test-resources</directory>
           <filtering>true</filtering>
       </testResource>
   </testResources>
   
   <plugins>
   
       <!-- Unzip shared resources -->
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-dependency-plugin</artifactId>
           <executions>
               <execution>
                   <id>unpack-cfg-test-resources</id>
                   <goals>
                       <goal>unpack-dependencies</goal>
                   </goals>
                   <phase>generate-test-resources</phase>
                   <configuration>
                       <outputDirectory>${project.build.directory}/test-resources</outputDirectory>
                       <includeArtifactIds>cfg_dev</includeArtifactIds>
                       <includeGroupIds>${project.groupId}</includeGroupIds>
                       <excludeTransitive>true</excludeTransitive>
                       <excludeTypes>pom</excludeTypes>
                       <scope>test</scope>
                   </configuration>
               </execution>
           </executions>
       </plugin>
     </plugins>
   

I hope this is clear and that will help you 🙂