10 files changed, 79 insertions, 50 deletions
diff --git a/src/main/scala/xyz/driver/core/Refresh.scala b/src/main/scala/xyz/driver/core/Refresh.scala
index ca28da7..e66b22f 100644
--- a/src/main/scala/xyz/driver/core/Refresh.scala
+++ b/src/main/scala/xyz/driver/core/Refresh.scala
@@ -8,8 +8,8 @@ import scala.concurrent.duration.Duration
 
 /** A single-value asynchronous cache with TTL.
   *
-  * Slightly adapted from Twitter's "util" library
-  * https://github.com/twitter/util/blob/ae0ab09134414438af9dfaa88a4613cecbff4741/util-cache/src/main/scala/com/twitter/cache/Refresh.scala
+  * Slightly adapted from
+  * [[https://github.com/twitter/util/blob/ae0ab09134414438af9dfaa88a4613cecbff4741/util-cache/src/main/scala/com/twitter/cache/Refresh.scala Twitter's "util" library]]
   *
   * Released under the Apache License 2.0.
   */
@@ -17,15 +17,27 @@ object Refresh {
 
   /** Creates a function that will provide a cached value for a given time-to-live (TTL).
     *
+    * It avoids the "thundering herd" problem if multiple requests arrive
+    * simultanously and the cached value has expired or is unset.
+    *
+    * Usage example:
     * {{{
     * def freshToken(): Future[String] = // expensive network call to get an access token
-    * val getToken: Future[String] = Refresh.every(1.hour)(freshToken())
+    * val getToken: () => Future[String] = Refresh.every(1.hour)(freshToken())
     *
     * getToken() // new token is issued
     * getToken() // subsequent calls use the cached token
     * // wait 1 hour
     * getToken() // new token is issued
-    * }}} */
+    * }}}
+    *
+    * @param ttl Time-To-Live duration to cache a computed value.
+    * @param compute Call-by-name operation that eventually computes a value to
+    * be cached. Note that if the computation (i.e. the future) fails, the value
+    * is not cached.
+    * @param ec The execution context in which valeu computations will be run.
+    * @return A zero-arg function that returns the cached value.
+    */
   def every[A](ttl: Duration)(compute: => Future[A])(implicit ec: ExecutionContext): () => Future[A] = {
     val ref = new AtomicReference[(Future[A], Instant)](
       (Future.failed(new NoSuchElementException("Cached value was never computed")), Instant.MIN)
diff --git a/src/main/scala/xyz/driver/core/app/init.scala b/src/main/scala/xyz/driver/core/app/init.scala
index f1e80b9..b638fd3 100644
--- a/src/main/scala/xyz/driver/core/app/init.scala
+++ b/src/main/scala/xyz/driver/core/app/init.scala
@@ -15,6 +15,7 @@ import xyz.driver.tracing.{GoogleTracer, NoTracer, Tracer}
 
 import scala.concurrent.ExecutionContext
 import scala.util.Try
+import scala.language.reflectiveCalls
 
 object init {
 
diff --git a/src/main/scala/xyz/driver/core/cache.scala b/src/main/scala/xyz/driver/core/cache.scala
index 3500a2a..9897c16 100644
--- a/src/main/scala/xyz/driver/core/cache.scala
+++ b/src/main/scala/xyz/driver/core/cache.scala
@@ -89,8 +89,8 @@ object cache {
 
   object AsyncCache {
     val DEFAULT_CAPACITY: Long             = 10000L
-    val DEFAULT_READ_EXPIRATION: Duration  = 10 minutes
-    val DEFAULT_WRITE_EXPIRATION: Duration = 1 hour
+    val DEFAULT_READ_EXPIRATION: Duration  = 10.minutes
+    val DEFAULT_WRITE_EXPIRATION: Duration = 1.hour
 
     def apply[K <: AnyRef, V <: AnyRef](
         name: String,
diff --git a/src/main/scala/xyz/driver/core/core.scala b/src/main/scala/xyz/driver/core/core.scala
index 72237b9..a654e85 100644
--- a/src/main/scala/xyz/driver/core/core.scala
+++ b/src/main/scala/xyz/driver/core/core.scala
@@ -7,9 +7,12 @@ import xyz.driver.core.rest.errors.ExternalServiceException
 
 import scala.concurrent.{ExecutionContext, Future}
 
-package object core {
+// TODO: this package seems too complex, look at all the features we need!
+import scala.language.reflectiveCalls
+import scala.language.higherKinds
+import scala.language.implicitConversions
 
-  import scala.language.reflectiveCalls
+package object core {
 
   def make[T](v: => T)(f: T => Unit): T = {
     val value = v
diff --git a/src/main/scala/xyz/driver/core/database/Repository.scala b/src/main/scala/xyz/driver/core/database/Repository.scala
index 31c79ad..5d7f787 100644
--- a/src/main/scala/xyz/driver/core/database/Repository.scala
+++ b/src/main/scala/xyz/driver/core/database/Repository.scala
@@ -6,6 +6,7 @@ import slick.lifted.{AbstractTable, CanBeQueryCondition, RunnableCompiled}
 import slick.{lifted => sl}
 
 import scala.concurrent.{ExecutionContext, Future}
+import scala.language.higherKinds
 
 trait Repository {
   type T[D]
diff --git a/src/main/scala/xyz/driver/core/file/S3Storage.scala b/src/main/scala/xyz/driver/core/file/S3Storage.scala
index 5158d4d..a869919 100644
--- a/src/main/scala/xyz/driver/core/file/S3Storage.scala
+++ b/src/main/scala/xyz/driver/core/file/S3Storage.scala
@@ -64,20 +64,24 @@ class S3Storage(s3: AmazonS3, bucket: Name[Bucket], executionContext: ExecutionC
       def isInSubFolder(path: Path)(fileLink: FileLink) =
         fileLink.location.toString.replace(path.toString + "/", "").contains("/")
 
-      Iterator.continually(s3.listObjectsV2(req)).takeWhile { result =>
-        req.setContinuationToken(result.getNextContinuationToken)
-        result.isTruncated
-      } flatMap { result =>
-        result.getObjectSummaries.asScala.toList.map { summary =>
-          FileLink(
-            Name[File](summary.getKey),
-            Paths.get(path.toString + "/" + summary.getKey),
-            Revision[File](summary.getETag),
-            Time(summary.getLastModified.getTime),
-            summary.getSize
-          )
-        } filterNot isInSubFolder(path)
-      } toList
+      Iterator
+        .continually(s3.listObjectsV2(req))
+        .takeWhile { result =>
+          req.setContinuationToken(result.getNextContinuationToken)
+          result.isTruncated
+        }
+        .flatMap { result =>
+          result.getObjectSummaries.asScala.toList.map { summary =>
+            FileLink(
+              Name[File](summary.getKey),
+              Paths.get(path.toString + "/" + summary.getKey),
+              Revision[File](summary.getETag),
+              Time(summary.getLastModified.getTime),
+              summary.getSize
+            )
+          } filterNot isInSubFolder(path)
+        }
+        .toList
     })
 
   override def exists(path: Path): Future[Boolean] = Future {
diff --git a/src/main/scala/xyz/driver/core/messaging/Bus.scala b/src/main/scala/xyz/driver/core/messaging/Bus.scala
index e2ee76a..599af92 100644
--- a/src/main/scala/xyz/driver/core/messaging/Bus.scala
+++ b/src/main/scala/xyz/driver/core/messaging/Bus.scala
@@ -2,6 +2,7 @@ package xyz.driver.core
 package messaging
 
 import scala.concurrent._
+import scala.language.higherKinds
 
 /** Base trait for representing message buses.
   *
diff --git a/src/main/scala/xyz/driver/core/rest/package.scala b/src/main/scala/xyz/driver/core/rest/package.scala
index 7d67138..c778b62 100644
--- a/src/main/scala/xyz/driver/core/rest/package.scala
+++ b/src/main/scala/xyz/driver/core/rest/package.scala
@@ -191,18 +191,21 @@ object `package` {
     request.headers.find(_.name == ContextHeaders.StacktraceHeader).fold("")(_.value()).split("->")
 
   def extractContextHeaders(request: HttpRequest): Map[String, String] = {
-    request.headers.filter { h =>
-      h.name === ContextHeaders.AuthenticationTokenHeader || h.name === ContextHeaders.TrackingIdHeader ||
-      h.name === ContextHeaders.PermissionsTokenHeader || h.name === ContextHeaders.StacktraceHeader ||
-      h.name === ContextHeaders.TraceHeaderName || h.name === ContextHeaders.SpanHeaderName ||
-      h.name === ContextHeaders.OriginatingIpHeader || h.name === ContextHeaders.ClientFingerprintHeader
-    } map { header =>
-      if (header.name === ContextHeaders.AuthenticationTokenHeader) {
-        header.name -> header.value.stripPrefix(ContextHeaders.AuthenticationHeaderPrefix).trim
-      } else {
-        header.name -> header.value
+    request.headers
+      .filter { h =>
+        h.name === ContextHeaders.AuthenticationTokenHeader || h.name === ContextHeaders.TrackingIdHeader ||
+        h.name === ContextHeaders.PermissionsTokenHeader || h.name === ContextHeaders.StacktraceHeader ||
+        h.name === ContextHeaders.TraceHeaderName || h.name === ContextHeaders.SpanHeaderName ||
+        h.name === ContextHeaders.OriginatingIpHeader || h.name === ContextHeaders.ClientFingerprintHeader
+      }
+      .map { header =>
+        if (header.name === ContextHeaders.AuthenticationTokenHeader) {
+          header.name -> header.value.stripPrefix(ContextHeaders.AuthenticationHeaderPrefix).trim
+        } else {
+          header.name -> header.value
+        }
       }
-    } toMap
+      .toMap
   }
 
   private[rest] def escapeScriptTags(byteString: ByteString): ByteString = {
diff --git a/src/main/scala/xyz/driver/core/swagger.scala b/src/main/scala/xyz/driver/core/swagger.scala
index 6567290..0c1e15d 100644
--- a/src/main/scala/xyz/driver/core/swagger.scala
+++ b/src/main/scala/xyz/driver/core/swagger.scala
@@ -69,24 +69,27 @@ object swagger {
         chain: util.Iterator[ModelConverter]): Property = {
       val javaType = Json.mapper().constructType(`type`)
 
-      Option(javaType.getRawClass) flatMap { cls =>
-        customProperties.get(cls)
-      } orElse {
-        `type` match {
-          case rt: ReferenceType if isOption(javaType.getRawClass) && chain.hasNext =>
-            val nextType = rt.getContentType
-            val nextResolved = Option(resolveProperty(nextType, context, annotations, chain)).getOrElse(
-              chain.next().resolveProperty(nextType, context, annotations, chain))
-            nextResolved.setRequired(false)
-            Option(nextResolved)
-          case t if chain.hasNext =>
-            val nextResolved = chain.next().resolveProperty(t, context, annotations, chain)
-            nextResolved.setRequired(true)
-            Option(nextResolved)
-          case _ =>
-            Option.empty[Property]
+      Option(javaType.getRawClass)
+        .flatMap { cls =>
+          customProperties.get(cls)
         }
-      } orNull
+        .orElse {
+          `type` match {
+            case rt: ReferenceType if isOption(javaType.getRawClass) && chain.hasNext =>
+              val nextType = rt.getContentType
+              val nextResolved = Option(resolveProperty(nextType, context, annotations, chain)).getOrElse(
+                chain.next().resolveProperty(nextType, context, annotations, chain))
+              nextResolved.setRequired(false)
+              Option(nextResolved)
+            case t if chain.hasNext =>
+              val nextResolved = chain.next().resolveProperty(t, context, annotations, chain)
+              nextResolved.setRequired(true)
+              Option(nextResolved)
+            case _ =>
+              Option.empty[Property]
+          }
+        }
+        .orNull
     }
 
     @SuppressWarnings(Array("org.wartremover.warts.Null"))
diff --git a/src/main/scala/xyz/driver/core/time.scala b/src/main/scala/xyz/driver/core/time.scala
index c7a32ad..1622068 100644
--- a/src/main/scala/xyz/driver/core/time.scala
+++ b/src/main/scala/xyz/driver/core/time.scala
@@ -8,6 +8,7 @@ import java.util.concurrent.TimeUnit
 import xyz.driver.core.date.Month
 
 import scala.concurrent.duration._
+import scala.language.implicitConversions
 import scala.util.Try
 
 object time {