Introducing Akka stream attributes in order to configure http request a…

…kka#3253

azure-storage/src/main/scala/akka/stream/alpakka/azure/storage/StorageAttributes.scala

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) since 2016 Lightbend Inc. <https://www.lightbend.com>
+ */
+
+package akka.stream.alpakka
+package azure
+package storage
+
+import akka.stream.Attributes
+import akka.stream.Attributes.Attribute
+
+/**
+ * Akka Stream attributes that are used when materializing AzureStorage stream blueprints.
+ */
+object StorageAttributes {
+
+  /**
+   * Settings to use for the S3 stream
+   */
+  def settings(settings: StorageSettings): Attributes = Attributes(StorageSettingsValue(settings))
+
+  /**
+   * Config path which will be used to resolve required AzureStorage settings
+   */
+  def settingsPath(path: String): Attributes = Attributes(StorageSettingsPath(path))
+}
+
+final class StorageSettingsPath private (val path: String) extends Attribute
+object StorageSettingsPath {
+  val Default: StorageSettingsPath = StorageSettingsPath(StorageSettings.ConfigPath)
+
+  def apply(path: String) = new StorageSettingsPath(path)
+}
+
+final class StorageSettingsValue private (val settings: StorageSettings) extends Attribute
+object StorageSettingsValue {
+  def apply(settings: StorageSettings) = new StorageSettingsValue(settings)
+}

azure-storage/src/main/scala/akka/stream/alpakka/azure/storage/StorageExt.scala

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+/*
+ * Copyright (C) since 2016 Lightbend Inc. <https://www.lightbend.com>
+ */
+
+package akka.stream.alpakka
+package azure
+package storage
+
+import akka.actor.{
+  ActorSystem,
+  ClassicActorSystemProvider,
+  ExtendedActorSystem,
+  Extension,
+  ExtensionId,
+  ExtensionIdProvider
+}
+
+/**
+ * Manages one [[StorageSettings]] per `ActorSystem`.
+ */
+final class StorageExt private (sys: ExtendedActorSystem) extends Extension {
+  val settings: StorageSettings = settings(StorageSettings.ConfigPath)
+
+  def settings(prefix: String): StorageSettings = StorageSettings(sys.settings.config.getConfig(prefix))
+}
+
+object StorageExt extends ExtensionId[StorageExt] with ExtensionIdProvider {
+  override def lookup: StorageExt.type = StorageExt
+  override def createExtension(system: ExtendedActorSystem) = new StorageExt(system)
+
+  /**
+   * Java API.
+   * Get the Storage extension with the classic actors API.
+   */
+  override def get(system: ActorSystem): StorageExt = super.apply(system)
+
+  /**
+   * Java API.
+   * Get the Storage extension with the new actors API.
+   */
+  override def get(system: ClassicActorSystemProvider): StorageExt = super.apply(system)
+}