3 files changed, 39 insertions, 0 deletions
diff --git a/scalalib/src/dependency/metadata/MavenMetadataLoader.scala b/scalalib/src/dependency/metadata/MavenMetadataLoader.scala
new file mode 100644
index 00000000..491911bf
--- /dev/null
+++ b/scalalib/src/dependency/metadata/MavenMetadataLoader.scala
@@ -0,0 +1,21 @@
+package mill.scalalib.dependency.metadata
+
+import coursier.Cache
+import coursier.maven.MavenRepository
+import coursier.util.Task
+import mill.scalalib.dependency.versions.Version
+
+private[dependency] final case class MavenMetadataLoader(mavenRepo: MavenRepository)
+    extends MetadataLoader {
+
+  private val fetch = Cache.fetch[Task]()
+
+  override def getVersions(module: coursier.Module): List[Version] = {
+    import scala.concurrent.ExecutionContext.Implicits.global
+    // TODO fallback to 'versionsFromListing' if 'versions' doesn't work? (needs to be made public in coursier first)
+    val allVersions = mavenRepo.versions(module, fetch).run.unsafeRun
+    allVersions
+      .map(_.available.map(Version(_)))
+      .getOrElse(List.empty)
+  }
+}
diff --git a/scalalib/src/dependency/metadata/MetadataLoader.scala b/scalalib/src/dependency/metadata/MetadataLoader.scala
new file mode 100644
index 00000000..20271f0e
--- /dev/null
+++ b/scalalib/src/dependency/metadata/MetadataLoader.scala
@@ -0,0 +1,7 @@
+package mill.scalalib.dependency.metadata
+
+import mill.scalalib.dependency.versions.Version
+
+private[dependency] trait MetadataLoader {
+  def getVersions(module: coursier.Module): Seq[Version]
+}
diff --git a/scalalib/src/dependency/metadata/MetadataLoaderFactory.scala b/scalalib/src/dependency/metadata/MetadataLoaderFactory.scala
new file mode 100644
index 00000000..4495d6b0
--- /dev/null
+++ b/scalalib/src/dependency/metadata/MetadataLoaderFactory.scala
@@ -0,0 +1,11 @@
+package mill.scalalib.dependency.metadata
+
+import coursier.Repository
+import coursier.maven.MavenRepository
+
+private[dependency] object MetadataLoaderFactory {
+  def apply(repo: Repository): Option[MetadataLoader] = repo match {
+    case mavenRepo: MavenRepository => Some(MavenMetadataLoader(mavenRepo))
+    case _                          => None
+  }
+}