What is it?

Njord is a Maven 3 and Maven 4 extension that offers local staging, repository operations and repository publishing. More precisely, Njord is a Resolver 1.x and 2.x extension (is yet another RepositoryConnector) that is loaded via Maven extensions mechanism and extends Resolver. Njord does not mingle with your build at all.

Njord supports “templates”, that define repository properties. Based on template a repository (“artifact store” in Njord lingo) is created. And those repositories can be merged, redeployed, dropped, validated or published (and more coming). Also, based on chosen template, Resolver is configured to deploy mandatory checksums for you. On the other hand, mandatory signatures are NOT generated, it is you who must provide them as part of your build.

In short, Njord keeps things “as before” (as without it): user never had to worry about checksums (Resolver did generate them always), while the signatures are usually provided by a plugin enabled in “release profile”. Njord goes step forward, and IF user selects any “SCA” template
(“SCA” stands for “Stronger Checksum Algorithms”, see Resolver Checksums) it will configure Resolver, and it will implicitly generate required stronger checksums without any user intervention required.

For now, templates supported out of the box are:

The njord: URI

Njord can be considered also as new transport for Maven. It defines the njord: URI prefix and supports several forms:

• njord: URI is a shorthand for njord:release-sca (default template), see below.
• njord:<TEMPLATE> is equivalent to njord:template:<TEMPLATE>, see below.
• njord:template:<TEMPLATE> URI when deployed to, will create new store using given template.
• njord:store:<STORE> URI when deployed to, will try to deploy to given store that already must exist (will not be created).

Similarly, to use Njord URIs in cases like maven-deploy-plugin parameter for alternate deployment repository, the format accepts id::uri formatted string, so Njord URIs looks like id::njord: or id::njord:template:release-sca with one important detail: the id repository ID is there only to fulfil syntactical requirements, is unused otherwise. Store name will be determined at the moment of creation.

Example URIs:

• njord: - means “use default template and create a new store” that is release-sca.
• njord:snapshot - means “use template by name snapshot and create a new store”.
• njord:store:release-00001 - means “select existing store release-00001 and use that”.

Basically by setting up your POM with distribution release repository using URL njord: and snapshot repository using URL njord:snapshot you are ready to use Njord. But, Njord is not intrusive, you can still use it by doing nothing in your project and just deploying with -DaltDeploymentRepository=id::njord: as well.

Hints:

• use mvn njord:list to list existing stores, see list Mojo
• use mvn njord:list-templates to list existing templates, see list-templates Mojo