Merge pull request #16207 from spray/w/16084-CustomHeader-model

+htc #16084 introduce CustomHeader superclass for user-defined headers

akka-http-core/src/main/java/akka/http/model/japi/headers/CustomHeader.java

@@ -0,0 +1,12 @@
+/*
+ * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
+ */
+
+package akka.http.model.japi.headers;
+
+public abstract class CustomHeader extends akka.http.model.HttpHeader {
+    public abstract String name();
+    public abstract String value();
+
+    protected abstract boolean suppressRendering();
+}

akka-http-core/src/main/scala/akka/http/engine/rendering/HttpRequestRendererFactory.scala

@@ -77,6 +77,10 @@ private[http] class HttpRequestRendererFactory(userAgentHeader: Option[headers.`
             case x: `Raw-Request-URI` ⇒ // we never render this header
               renderHeaders(tail, hostHeaderSeen, userAgentSeen, transferEncodingSeen)
 
+            case x: CustomHeader ⇒
+              if (!x.suppressRendering) render(x)
+              renderHeaders(tail, hostHeaderSeen, userAgentSeen, transferEncodingSeen)
+
             case x: RawHeader if (x is "content-type") || (x is "content-length") || (x is "transfer-encoding") ||
               (x is "host") || (x is "user-agent") ⇒
               suppressionWarning(log, x, "illegal RawHeader")

akka-http-core/src/main/scala/akka/http/engine/rendering/HttpResponseRendererFactory.scala

@@ -105,6 +105,10 @@ private[http] class HttpResponseRendererFactory(serverHeader: Option[headers.Ser
               render(x)
               renderHeaders(tail, alwaysClose, connHeader, serverHeaderSeen = true, transferEncodingSeen)
 
+            case x: CustomHeader ⇒
+              if (!x.suppressRendering) render(x)
+              renderHeaders(tail, alwaysClose, connHeader, serverHeaderSeen, transferEncodingSeen)
+
             case x: RawHeader if (x is "content-type") || (x is "content-length") || (x is "transfer-encoding") ||
               (x is "date") || (x is "server") || (x is "connection") ⇒
               suppressionWarning(log, x, "illegal RawHeader")

akka-http-core/src/main/scala/akka/http/model/headers/headers.scala

@@ -30,6 +30,17 @@ sealed trait ModeledHeader extends HttpHeader with Serializable {
   protected def companion: ModeledCompanion
 }
 
+/**
+ * Superclass for user-defined custom headers defined by implementing `name` and `value`.
+ */
+abstract class CustomHeader extends japi.headers.CustomHeader {
+  /** Override to return true if this header shouldn't be rendered */
+  def suppressRendering: Boolean = false
+
+  def lowercaseName: String = name.toRootLowerCase
+  def render[R <: Rendering](r: R): r.type = r ~~ name ~~ ':' ~~ ' ' ~~ value
+}
+
 import japi.JavaMapping.Implicits._
 
 // http://tools.ietf.org/html/rfc7230#section-6.1

akka-http-core/src/test/scala/akka/http/engine/rendering/RequestRendererSpec.scala

@@ -190,6 +190,35 @@ class RequestRendererSpec extends FreeSpec with Matchers with BeforeAndAfterAll
         }
       }
     }
+    "render a CustomHeader header" - {
+      "if suppressRendering = false" in new TestSetup(None) {
+        case class MyHeader(number: Int) extends CustomHeader {
+          def name: String = "X-My-Header"
+          def value: String = s"No$number"
+        }
+        HttpRequest(GET, "/abc", List(MyHeader(5))) should renderTo {
+          """GET /abc HTTP/1.1
+            |X-My-Header: No5
+            |Host: test.com:8080
+            |
+            |"""
+        }
+      }
+      "not if suppressRendering = true" in new TestSetup(None) {
+        case class MyInternalHeader(number: Int) extends CustomHeader {
+          override def suppressRendering: Boolean = true
+
+          def name: String = "X-My-Internal-Header"
+          def value: String = s"No$number"
+        }
+        HttpRequest(GET, "/abc", List(MyInternalHeader(5))) should renderTo {
+          """GET /abc HTTP/1.1
+            |Host: test.com:8080
+            |
+            |"""
+        }
+      }
+    }
 
     "properly use URI from Raw-Request-URI header if present" - {
       "GET request with Raw-Request-URI" in new TestSetup() {

akka-http-core/src/test/scala/akka/http/engine/rendering/ResponseRendererSpec.scala

@@ -4,6 +4,7 @@
 
 package akka.http.engine.rendering
 
+import akka.http.model.HttpMethods._
 import com.typesafe.config.{ Config, ConfigFactory }
 import scala.concurrent.duration._
 import scala.concurrent.Await
@@ -314,6 +315,38 @@ class ResponseRendererSpec extends FreeSpec with Matchers with BeforeAndAfterAll
       }
     }
 
+    "render a CustomHeader header" - {
+      "if suppressRendering = false" in new TestSetup(None) {
+        case class MyHeader(number: Int) extends CustomHeader {
+          def name: String = "X-My-Header"
+          def value: String = s"No$number"
+        }
+        HttpResponse(200, List(MyHeader(5))) should renderTo {
+          """HTTP/1.1 200 OK
+            |X-My-Header: No5
+            |Date: Thu, 25 Aug 2011 09:10:29 GMT
+            |Content-Length: 0
+            |
+            |"""
+        }
+      }
+      "not if suppressRendering = true" in new TestSetup(None) {
+        case class MyInternalHeader(number: Int) extends CustomHeader {
+          override def suppressRendering: Boolean = true
+
+          def name: String = "X-My-Internal-Header"
+          def value: String = s"No$number"
+        }
+        HttpResponse(200, List(MyInternalHeader(5))) should renderTo {
+          """HTTP/1.1 200 OK
+            |Date: Thu, 25 Aug 2011 09:10:29 GMT
+            |Content-Length: 0
+            |
+            |"""
+        }
+      }
+    }
+
     "The 'Connection' header should be rendered correctly" in new TestSetup() {
       import org.scalatest.prop.TableDrivenPropertyChecks._
       import HttpProtocols._