1 files changed, 89 insertions, 0 deletions
diff --git a/core-init/src/main/scala/xyz/driver/core/init/CloudServices.scala b/core-init/src/main/scala/xyz/driver/core/init/CloudServices.scala
new file mode 100644
index 0000000..857dd4c
--- /dev/null
+++ b/core-init/src/main/scala/xyz/driver/core/init/CloudServices.scala
@@ -0,0 +1,89 @@
+package xyz.driver.core
+package init
+
+import java.nio.file.Paths
+
+import xyz.driver.core.messaging.{CreateOnDemand, GoogleBus, QueueBus, StreamBus}
+import xyz.driver.core.reporting._
+import xyz.driver.core.rest.DnsDiscovery
+import xyz.driver.core.storage.{BlobStorage, FileSystemBlobStorage, GcsBlobStorage}
+
+import scala.collection.JavaConverters._
+
+/** Mixin trait that provides essential cloud utilities. */
+trait CloudServices extends AkkaBootable { self =>
+
+  /** The platform that this application is running on.
+    * @group config
+    */
+  def platform: Platform = Platform.current
+
+  /** Service discovery for the current platform.
+    * @group utilities
+    */
+  lazy val discovery: DnsDiscovery = {
+    def getOverrides(): Map[String, String] = {
+      val block = config.getObject("services.dev-overrides").unwrapped().asScala
+      for ((key, value) <- block) yield {
+        require(value.isInstanceOf[String], s"Service URL override for '$key' must be a string. Found '$value'.")
+        key -> value.toString
+      }
+    }.toMap
+    val overrides = platform match {
+      case Platform.Dev => getOverrides()
+      // TODO: currently, deployed services must be configured via Kubernetes DNS resolver. Maybe we may want to
+      // provide a way to override deployed services as well.
+      case _ => Map.empty[String, String]
+    }
+    new DnsDiscovery(clientTransport, overrides)
+  }
+
+  /* TODO: this reporter uses the platform to determine if JSON logging should be enabled.
+   * Since the default logger uses slf4j, its settings must be specified before a logger
+   * is first accessed. This in turn leads to somewhat convoluted code,
+   * since we can't log when the platform being is determined.
+   * A potential fix would be to make the log format independent of the platform, and always log
+   * as JSON for example.
+   */
+  override lazy val reporter: Reporter with ScalaLoggingCompat = {
+    Console.println("determining platform") // scalastyle:ignore
+    val r = platform match {
+      case p @ Platform.GoogleCloud(_, _) =>
+        new GoogleReporter(p.credentials, p.namespace) with ScalaLoggingCompat with GoogleMdcLogger {
+          val logger = ScalaLoggingCompat.defaultScalaLogger(true)
+        }
+      case Platform.Dev =>
+        new NoTraceReporter with ScalaLoggingCompat {
+          val logger = ScalaLoggingCompat.defaultScalaLogger(false)
+        }
+    }
+    r.info(s"application started on platform '${platform}'")(SpanContext.fresh())
+    r
+  }
+
+  /** Object storage.
+    *
+    * When running on a cloud platform, prepends `$project-` to bucket names, where `$project`
+    * is the project ID (for example 'driverinc-production` or `driverinc-sandbox`).
+    *
+    * @group utilities
+    */
+  def storage(bucketName: String): BlobStorage =
+    platform match {
+      case p @ Platform.GoogleCloud(keyfile, _) =>
+        GcsBlobStorage.fromKeyfile(keyfile, s"${p.project}-$bucketName")
+      case Platform.Dev =>
+        new FileSystemBlobStorage(Paths.get(s".data-$bucketName"))
+    }
+
+  /** Message bus.
+    * @group utilities
+    */
+  def messageBus: StreamBus = platform match {
+    case p @ Platform.GoogleCloud(_, namespace) =>
+      new GoogleBus(p.credentials, namespace) with StreamBus with CreateOnDemand
+    case Platform.Dev =>
+      new QueueBus()(self.system) with StreamBus
+  }
+
+}