Example for providing cbt's classloader to Akka

2 files changed, 43 insertions, 0 deletions

diff --git a/examples/akka-example/Main.scala b/examples/akka-example/Main.scala
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+++ b/examples/akka-example/Main.scala
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+package cbt_examples.akka_example
+
+import akka.http.scaladsl.server._
+import akka.http.scaladsl.model._
+import akka.http.scaladsl.server.Directives._
+import akka.http.scaladsl.settings._
+
+object Service extends HttpApp with App {
+  override protected def route =
+    path("test") {
+      get {
+        complete(HttpResponse())
+      }
+    }
+
+  // CBT isolates it's classloaders. Even when using `direct` mode and a flatClassLoader,
+  // it will not use the jvm's system classloader stack for the application.
+  // This means if applications are hard-coded against the system classloader,
+  // e.g. for loading configuration files from their users or their own jars,
+  // they will not find them. One way around this is telling CBT to fork the process.
+  // (via `override def fork = true` in your build)
+  // This "just" works, but you'll loose all caching speedup benefits.
+  // Alternatively, applications like akka often allow providing a custom
+  // classloader instead and then benefit from CBT's classloader caching. Here is how:
+  val system = akka.actor.ActorSystem( "my-actor-system", classLoader = Some(this.getClass.getClassLoader) )
+  startServer("localhost", 8080, ServerSettings(system), system)
+}
diff --git a/examples/akka-example/build/build.scala b/examples/akka-example/build/build.scala
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+++ b/examples/akka-example/build/build.scala
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+package cbt_examples_build.akka_example
+
+import cbt._
+import java.net.URL
+
+class Build(val context: Context) extends BaseBuild {
+
+  override def defaultScalaVersion = "2.12.1"
+
+  override def dependencies =
+    super.dependencies ++
+    Resolver(mavenCentral).bind(
+      ScalaDependency("com.typesafe.akka", "akka-http", "10.0.5")
+    )
+
+}