extractMaterializer

Signature

def extractMaterializer: Directive1[Materializer]

Description

Extracts the MaterializerMaterializer from the RequestContextRequestContext, which can be useful when you want to run an Akka Stream directly in your route.

See also withMaterializer to see how to customise the used materializer for specific inner routes.

Example

Scala
val route =
  path("sample") {
    extractMaterializer { materializer =>
      complete {
        // explicitly use the `materializer`:
        Source.single(s"Materialized by ${materializer.##}!")
          .runWith(Sink.head)(materializer)
      }
    }
  } // default materializer will be used

// tests:
Get("/sample") ~> route ~> check {
  responseAs[String] shouldEqual s"Materialized by ${materializer.##}!"
}
Java
import static akka.http.javadsl.server.Directives.extractMaterializer;

final Route route = path("sample", () ->
  extractMaterializer(mat ->
    onSuccess(() ->
      // explicitly use the materializer:
      Source.single("Materialized by " + mat.hashCode() + "!")
        .runWith(Sink.head(), mat), Directives::complete
    )
  )
); // default materializer will be used

testRoute(route).run(HttpRequest.GET("/sample"))
  .assertEntity("Materialized by " + materializer().hashCode()+ "!");
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