Merge pull request #453 from atomist/empty

Allow construction of Message without a body

CHANGELOG.md

@@ -9,6 +9,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 [Unreleased]: https://github.com/atomist/rug/compare/0.17.1...HEAD
 
+### Changed
+
+-   Allow construction of Message without body
+
 ## [0.17.1] - 2017-03-20
 
 [0.17.1]: https://github.com/atomist/rug/compare/0.17.0...0.17.1

src/main/scala/com/atomist/rug/runtime/js/PlanBuilder.scala

@@ -7,7 +7,7 @@ import com.atomist.rug.spi.Handlers._
 import com.atomist.tree.TreeNode
 import com.atomist.util.JsonUtils
 import jdk.nashorn.api.scripting.ScriptObjectMirror
-import jdk.nashorn.internal.runtime.Undefined
+import jdk.nashorn.internal.runtime.{ScriptRuntime, Undefined}
 
 /**
   * Constructs plans from Nashorn response to a Handler/handle operation
@@ -60,6 +60,7 @@ class PlanBuilder {
         JsonBody(json.entrySet().toString)
       case text: String =>
         MessageText(text)
+      case ScriptRuntime.UNDEFINED => MessageText(null)
       case _ =>
         throw new InvalidHandlerResultException(s"Cannot determine message content from body: ${jsMessage.getMember("body")}")
     }

src/test/resources/com/atomist/rug/runtime/js/interop/SimpleCommandHandlerReturningEmptyMessage.ts

@@ -0,0 +1,12 @@
+import {HandleCommand, Instruction, Response, HandlerContext, Plan, Message} from '@atomist/rug/operations/Handlers'
+import {CommandHandler, Parameter, Tags, Intent} from '@atomist/rug/operations/Decorators'
+
+@CommandHandler("ShowMeTheKitties","Search Youtube for kitty videos and post results to slack")
+class KittieFetcher implements HandleCommand{
+
+  handle(ctx: HandlerContext) : Message {
+    return new Message();
+  }
+}
+
+export let command = new KittieFetcher();

src/test/scala/com/atomist/rug/runtime/js/JavaScriptCommandHandlerTest.scala

@@ -9,6 +9,7 @@ import com.atomist.rug.spi.Handlers._
 import com.atomist.rug.spi.Secret
 import com.atomist.rug.ts.TypeScriptBuilder
 import com.atomist.source.{SimpleFileBasedArtifactSource, StringFileArtifact}
+import com.atomist.util.JsonUtils
 import org.scalatest.{FlatSpec, Matchers}
 
 import scala.concurrent.Await
@@ -41,6 +42,18 @@ class JavaScriptCommandHandlerTest extends FlatSpec with Matchers {
   val simpleCommandHandlerReturningMessage = StringFileArtifact(atomistConfig.handlersRoot + "/Handler.ts",
     contentOf(this, "SimpleCommandHandlerReturningMessage.ts"))
 
+  val simpleCommandHandlerReturningEmptyMessage = StringFileArtifact(atomistConfig.handlersRoot + "/Handler.ts",
+    contentOf(this, "SimpleCommandHandlerReturningEmptyMessage.ts"))
+
+  it should "allow us to return an empty message" in {
+    val rugArchive = TypeScriptBuilder.compileWithModel(SimpleFileBasedArtifactSource(simpleCommandHandlerReturningEmptyMessage))
+    val rugs = RugArchiveReader.find(rugArchive, Nil)
+    val com = rugs.commandHandlers.head
+    val plan = com.handle(null,SimpleParameterValues.Empty).get
+    assert(plan.messages.size === 1)
+    assert(plan.messages.head.body.value == null)
+    assert(JsonUtils.toJson(plan.messages.head) == """{"body":{},"instructions":[]}""")
+  }
   it should "allow us to return a message directly from a handler" in {
     val rugArchive = TypeScriptBuilder.compileWithModel(SimpleFileBasedArtifactSource(simpleCommandHandlerReturningMessage))
     val rugs = RugArchiveReader.find(rugArchive, Nil)