Maven, assembly plugin, multi-module project and module dependencies

Question

I'm building a multi-module Maven project whose major product is a WAR file, and I'm trying to assemble that file together with associated release-related artifacts (README, release notes, license file, etc.) into a ZIP for distribution. But when I try to build a distribution file, it fails. What am I doing wrong? Note that I have already checked that the foo-bar.1.0.war artifact exists at the point that the foo-distribution module is asked to build the distribution file; I'm aware that putting everything in foo's POM won't work. (I have a workaround; I can use relative paths to point directly to the location of the files distributed relative to the foo-distribution module root. This isn't a solution I like as it has bad code-smell.)

Note also that I always build from the root project, and that I'm using assembly:single in the distribution builder (as recommended in the Maven documentation).

Project Layout

foo
+ src
| + README.txt
+ foo-bar
| + target
|   + foo-bar.1.0.war
+ foo-distribution
  + src
    + assemble
      + dist.xml

foo and foo-distribution have pom packaging, and foo-bar has war packaging. (There are other modules in the real code, but they're also constructed correctly before the foo-distribution module.)

foo POM

<project xmlns="http://maven.apache.org/POM/4.0.0"&gt;
    <modelVersion>4.0.0</modelVersion>
    <groupId>foobar</groupId>
    <artifactId>foo</artifactId>
    <packaging>pom</packaging>
    <version>0.0.1-SNAPSHOT</version>

    <modules>
        <module>foo-bar</module>
        <module>foo-distribution</module>
    </modules>
</project>

foo-distribution POM

<project xmlns="http://maven.apache.org/POM/4.0.0"&gt;
    <modelVersion>4.0.0</modelVersion>
    <version>0.0.1-SNAPSHOT</version>
    <parent>
        <artifactId>foo</artifactId>
        <groupId>foobar</groupId>
        <version>0.0.1-SNAPSHOT</version>
        <relativePath>..</relativePath>
    </parent>
    <groupId>foobar</groupId>
    <artifactId>foo-distribution</artifactId>
    <packaging>pom</packaging>

    <dependencies>
        <dependency>
            <groupId>foobar</groupId>
            <artifactId>foo-bar</artifactId>
            <version>1.0</version>
            <type>war</type>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <version>2.2-beta-5</version>
                <configuration>
                    <finalName>foobar</finalName>
                    <descriptors>
                        <descriptor>src/assemble/dist.xml</descriptor>
                    </descriptors>
                </configuration>
                <executions>
                    <execution>
                        <id>make-t2server-distribution</id>
                        <phase>package</phase>
                        <goals>
                            <goal>single</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
</project>

dist.xml

<assembly
    xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.0"&gt;
    <id>distribution</id>
    <formats>
        <format>zip</format>
    </formats>
    <moduleSets>
        <moduleSet>
            <includes>
                <include>foobar:foo</include>
            </includes>
            <sources>
                <fileSets>
                    <fileSet>
                        <directory>src</directory>
                        <includes>
                            <include>*.txt</include>
                        </includes>
                    </fileSet>
                </fileSets>
            </sources>
        </moduleSet>
        <moduleSet>
            <includes>
                <include>foobar:foo-bar</include>
            </includes>
            <binaries />
        </moduleSet>
    </moduleSets>
</assembly>

Workaround dist.xml

This is the workaround that I mentioned above. It produces exactly the artifact that I want.

<assembly
    xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.0"&gt;
    <id>distribution</id>
    <formats>
        <format>zip</format>
    </formats>
    <fileSets>
        <fileSet>
            <directory>${project.basedir}/../src</directory>
            <includes>
                <include>*.txt</include>
            </includes>
        </fileSet>
        <fileSet>
            <directory>${project.basedir}/../foo-bar/target</directory>
            <includes>
                <include>*.war</include>
            </includes>
            <outputDirectory>.</outputDirectory>
        </fileSet>
    </fileSets>
</assembly>

Answer 1

You should use a dependencySet in your assembly descriptor

<assembly>
  <id>dist</id>
  <formats>
      <format>zip</format>
  </formats>
  <includeBaseDirectory>true</includeBaseDirectory>
  <dependencySets>
      <dependencySet>
          <useTransitiveDependencies>false</useTransitiveDependencies>
          <useProjectArtifact>false</useProjectArtifact>
          <unpack>false</unpack>
          <scope>runtime</scope>
          <fileMode>0644</fileMode>
      </dependencySet>
  </dependencySets>
  <fileSets>
      <fileSet>
        with all supplemental files you need
      </fileSet>
  </fileSets>

instead of referencing the files via file system (relative paths). And on the other hand a descriptor for source does exists already from the assembly plugin (take a look into the docs).