Targets are invoked as the first argument to the mj command line tool. For example, to invoke the clean target:

mj clean

Using Default Targets

makejack comes with several default targets/ To use these, you have to import them into your mj.edn file.

#mj {:targets
     #default-targets [:clean :pom :jar]}}

The targets are specified as a vector of keywords. To import all available targets pass the :all keyword, instead of the vector.

Defining New Targets

Targets are defined in the :targets key of mj.edn. Let’s look at the definition of the clean target, which is a default target in makejack.

#mj {…
 :targets
  {:clean {:doc #join ["Remove the " #ref [:target-path] " directory"]
           :invoker :shell
           :args ["rm" "-rf" #ref [:target-path]]
 …}}

The :invoker key is mandatory, and defines the way makejack invokes the build tool. Here we use the :shell invoker, which executes the shell command specified in the :args key.

The :doc key provides a docstring that is used to describe the target. The first line appears in the mj help output, and mj help clean shows the full doc string.

Referring to values in mj.edn and project.edn

Notice the use of aero #ref tag above to refer to other values in the mj.edn file.

The project.edn can also injected using the #project tag, should you want to refernce values defined there. For example, you could define an install target like this:

#mj {:project #project {:profile :jar}
     :targets {:install {:doc     "Install the API jar into the local repository."
                         :invoker :shell
                         :args    ["mvn" "install-file"
                                   #join ["-Dfile="
                                          #ref [:target-path]
                                          "/"
                                          #ref [:project :jar-name]]
                                   #join ["-DgroupId="
                                          #ref [:project :group-id]]
                                   #join ["-DartifactId="
                                          #ref [:project :artifact-id]]
                                   #join ["-Dversion="
                                          #ref [:project :version]]
                                   "-Dpackaging=jar"]}}}