How to configure Typesafe Activator *a priori* to use an existing local Maven repository?

Question

(Not found in the Activator documentation)
It seems that it is possible to have Activator also use an existing local Maven repository by adding the following entry (in bold) in file build.sbt:

resolvers += Seq( "Local Maven Repository" at "file://q:/repositories/maven",
"Sonatype OSS Snapshots" at "https://oss.sonatype.org/content/repositories/snapshots" )

I am not sure it works but anyway, the problem with this approach is that the project structure must already have been created (and therefore a local repository created and automatically populated by downloads), hence my question : is it possible to tell Activator before it creates the project structure that it should use some local Maven repository ?

Thanks in advance for any hint.

Answer 1

Activator makes use of the sbt-launcher. You can use the sbt-launcher to control which repositories sbt makes use of by default for each project and for the launcher itself.

If you'd like to modify the activator launcher itself, unzip the jar file and take a look at the sbt/boot.properties file included. You can use the format outlined at sbt's launcher docs to add your local maven repository to the list.

A simpler option in the future (but not enabled in our current properties file) is the launcher's ability to have an override repository configuration file. See: Sbt's proxy configuration docs. This file would allow you to specify the repositories you wish activator to use by default. We disabled this to ensure the offline repository which activator uses is added by default. However, I'll open a ticket to re-enable this feature. That way, you should be able to just create a ~/.sbt/repositories file with the following contents:

[repositories]
  activator-local: file://${activator.local.repository-${activator.home-${user.home}/.activator}/repository}, [organization]/[module]/(scala_[scalaVersion]/)(sbt_[sbtVersion]/)[revision]/[type]s/[artifact](-[classifier]).[ext]
  local
  maven-local
  maven-central
  typesafe-releases: http://typesafe.artifactoryonline.com/typesafe/releases
  typesafe-ivy-releases: http://typesafe.artifactoryonline.com/typesafe/ivy-releases, [organization]/[module]/(scala_[scalaVersion]/)(sbt_[sbtVersion]/)[revision]/[type]s/[artifact](-[classifier]).[ext]

Note: the ~/.sbt/boot directory will always exist. This is created to ensure that no other process deletes jar files we use while running, so we copy these out of the local cache. If we didn't, you'd see some really fun error messages.