Message Digest Assembly Handler

This is a plugin for the Maven Assembly Plugin that calculates Message Digests for the files in the archive. A typical possible outcome is a MD5SUMS file or SHA256SUMS file.

Requirements

The message-digest-assembly-handler requires at least the following environment:

• JDK 8 and later
• Maven-Assembly-Plugin 3.2.0 and later as a plugin in your pom.xml

Setup

You need to add the handler to your pom.xml and your assembly descriptor file. Examples are shown in the next subsections.

In your POM

In your pom.xml, add the message-digest-assembly-handler as a dependency to your maven-assembly-plugin plugin as described below.

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-assembly-plugin</artifactId>
  <version>3.2.0</version>
  <dependencies>
     <dependency>
       <groupId>de.sfuhrm</groupId>
       <artifactId>message-digest-assembly-handler</artifactId>
       <version>0.9.2</version>
     </dependency>
  </dependencies>
</plugin>

In your assembly descriptor

In your XML assembly descriptor, add one containerDescriptorHandler element:

<?xml version="1.0"?>
<assembly>
  <id>my-id</id>
  <formats>
    <format>jar</format>
  </formats>
  <containerDescriptorHandlers>
    <containerDescriptorHandler>
      <handlerName>message-digest</handlerName>
      <configuration>
        <messageDigest>MD5</messageDigest>
        <checksumFile>MD5SUMS</checksumFile>
      </configuration>
    </containerDescriptorHandler>
  </containerDescriptorHandlers>

Instead of the handlerName "message-digest" you can also directly refer to the shortcuts in the following table.

Message Digest	handlerName Parameter	Default checksumFile	Note
MD5 *	message-digest	MD5SUMS *	* default is MD5, overwriting is possible
MD5	message-digest-md5	MD5SUMS
SHA	message-digest-sha-1	SHA1SUMS	"SHA" in JDK refers to the SHA-1 algorithm
SHA-256	message-digest-sha-2-256	SHA256SUMS	SHA-2
SHA-512	message-digest-sha-2-512	SHA512SUMS	SHA-2

Note that overwriting the messageDigest and checksumFile is possible for every handlerName, but except the generic message-digest it will probably confuse to have a different algorithm that does not match the handler name.

Configuration

The handler declaration in the assembly descriptor understands the following configuration parameters:

• messageDigest: The name of a MessageDigest algorithm from the JDK. Defaults to MD5. The following lists the MessageDigest algorithms supported by AdoptOpenJDK13: MD2, MD5, SHA, SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224, SHA-512/256, SHA3-224, SHA3-256, SHA3-384, SHA3-512.

• checksumFile: The name of the checksum file generated. Defaults to MD5SUMS. Typical names are MD5SUMS, SHA1SUMS, and so on.

• exclusionRegex: A regular expression that defines what files shall not be handled by this handler. This option is important if you want to create multiple checksum files with multiple containerDescriptorHandler sections. You can then exclude the handlers from each other, for example by giving the regex (MD5SUMS|SHA1SUMS).