Maven Error reading assemblies: No assembly descriptors found

Question

Following this Guide I ran the command

mvn assembly:assembly

and got the Build Failure of

Error reading assemblies: No assembly descriptors found.

I've looked at numerous questions on this, but to no avail.

From this post, I created a .xml with this inside:

<assembly xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.2 http://maven.apache.org/xsd/assembly-1.1.2.xsd">
    <id>jar-with-dependencies</id>
    <formats>
        <format>jar</format>
    </formats>
    <dependencySets>
        <dependencySet>
            <scope>runtime</scope>
            <unpack>true</unpack>
            <unpackOptions>
                <excludes>
                    <exclude>**/LICENSE*</exclude>
                    <exclude>**/README*</exclude>
                </excludes>
            </unpackOptions>
        </dependencySet>
    </dependencySets>
    <fileSets>
        <fileSet>
            <directory>${project.build.outputDirectory}</directory>
            <outputDirectory>${project.build.outputDirectory}</outputDirectory>
        </fileSet>
        <fileSet>
            <directory>src/main/resources/META-INF/services</directory>
            <outputDirectory>META-INF/services</outputDirectory>
        </fileSet>
    </fileSets>
</assembly>

and included this in the pom.xml:

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <version>2.2-beta-5</version>
    <configuration>
      <descriptors>
        <descriptor>jar-with-dependencies.xml</descriptor>
        </descriptors>
    </configuration>
  </plugin>

but still no luck.

I'm pretty new to this as you can probably tell, how can I get this running?

~~EDIT~~

In the pom.xml I changed

<descriptor>jar-with-dependencies.xml</descriptor>

To

<descriptor>src/main/assembly/jar-with-dependencies.xml</descriptor>

~~EDIT 2~~

pom.xml now contains this:

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <version>2.2-beta-5</version>
    <executions>
        <execution>
        <id>make-assembly</id>
        <phase>package</phase>
        <goals>
            <goal>single</goal>
        </goals>
        <configuration>
        <descriptors>
            <descriptor>src/main/assembly/jar-with-dependencies.xml</descriptor>
        </descriptors>
        </configuration>
        </execution>
        </executions>
</plugin>

~~EDIT 3~~

This pom.xml now works for me:

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <version>2.2-beta-5</version>
    <configuration>
        <descriptors>
            <descriptor>src/main/assembly/jar-with-dependencies.xml</descriptor>
        </descriptors>
        </configuration>
    <executions>
        <execution>
        <id>make-assembly</id>
        <phase>package</phase>
        <goals>
            <goal>single</goal>
        </goals>
        </execution>
    </executions>
</plugin>

Solution

For this to work, you need to create the file jar-with-dependencies.xml in src/main/assembly/ and this XML:

<descriptors>
    <descriptor>src/main/assembly/jar-with-dependencies.xml</descriptor>
</descriptors>

i.e. you need to specify the path to the file and the convention is to put the files into src/main/assembly/.

To use the ones provided by Maven, you need to use the descriptorRef element instead (wrapped in a descriptorRefs).

Also don't put the descriptor inside of the execution element or mvn assembly:assembly can't find it anymore (since you specifically moved it to the mvn package target).

[EDIT] I followed the tutorial myself and there is an important point which you might have missed: You need to select the correct archetype. In my case, that was 5 but the order can change. So read the whole list and look for the string openimaj-quickstart-archetype or things will break.

Comments

[MLMLTL]

I cant find a src/assembly/

[Aaron Digulla]

@MLMLTL You need to create this folder.

[Aaron Digulla]

@MLMLTL: I checked again with one of my project; see my edits. If you created a custom XML file, you need to use descriptor and the path to the file (relative to ${basedir}).

[MLMLTL]

Again, still no luck -- PS </descriptor needs a >?

[Aaron Digulla]

Why are you using a beta version of the plugin? The latest release is 2.5.3. Try that

[Aaron Digulla]

Run mvn -X to get debug output. That should show you the absolute path which the plugin searches. Also check the documentation: maven.apache.org/plugins/maven-assembly-plugin/usage.html And help:effective-pom can show you the POM as Maven actually sees it.

[MLMLTL]

No goals have been specified for this build - So added that in (see edit) but is still saying that now

[Aaron Digulla]

Try mvn assembly:assembly -X :-)

[MLMLTL]

Failed to execute goal org.apache.maven.plugins:maven-assembly-plugin:2.2-beta5:ass‌​embly (default-cli) ... Error reading assemblies: No assembly descriptors found

[Aaron Digulla]

You're still using the old version of the plugin. The syntax in EDIT 2 should work. Are you executing Maven in the correct folder?

[MLMLTL]

How do I check that? I've cd'd into the project folder so it should be, right? - With the 2.5.3 still no different either.

[Aaron Digulla]

Have a look at this: stackoverflow.com/questions/5183460/…

[MLMLTL]

Thank You! It was the putting of <configuration> above the <executions> that solved it, submit it as an answer if you like :)

[Aaron Digulla]

The fully qualified name of the class which contains the main(String[]) method.

[MLMLTL]

Where do I get the main(String[]) method name from?

[Aaron Digulla]

The class name should be mentioned in the OpenIMAJ tutorial; isn't there a pom.xml in the sources already?

[MLMLTL]

I cant see it and there are many poms, inside of which I don't know where to look

[Aaron Digulla]

You probably chose the wrong archetype when creating the tutorial. Make sure you chose openimaj-quickstart-archetype when Maven asks which archetype you want (first question).

[MLMLTL]

I dont have a META-INF/MANIFEST.MF anywhere

[Aaron Digulla]

Any why is that a problem?