Add spray compatibility layer

7 files changed, 140 insertions, 3 deletions

diff --git a/build.sbt b/build.sbt
index 0708cb1..5ae0dc5 100644
--- a/build.sbt
+++ b/build.sbt
@@ -1,13 +1,17 @@
 // shadow sbt-scalajs' crossProject and CrossType until Scala.js 1.0.0 is released
 import sbtcrossproject.{crossProject, CrossType}
 
+val testSettings = Seq(
+  libraryDependencies += "com.lihaoyi" %%% "utest" % "0.6.4" % "test",
+  testFrameworks += new TestFramework("utest.runner.Framework")
+)
+
+
 lazy val yamlesque = crossProject(JSPlatform, JVMPlatform, NativePlatform)
   .crossType(CrossType.Pure)
+  .settings(testSettings)
   .settings(
-    libraryDependencies += "com.lihaoyi" %%% "utest" % "0.6.4" % "test",
-    testFrameworks += new TestFramework("utest.runner.Framework"),
     scalaVersion := crossScalaVersions.value.head
-
   )
   .jvmSettings(
     crossScalaVersions := "2.12.4" :: "2.11.12" :: Nil
@@ -23,3 +27,15 @@ lazy val yamlesque = crossProject(JSPlatform, JVMPlatform, NativePlatform)
 lazy val yamlesqueJVM    = yamlesque.jvm
 lazy val yamlesqueJS     = yamlesque.js
 lazy val yamlesqueNative = yamlesque.native
+
+lazy val yamlesqueSpray = crossProject(JSPlatform, JVMPlatform, NativePlatform)
+  .crossType(CrossType.Pure)
+  .in(file("yamlesque-spray"))
+  .dependsOn(yamlesque)
+  .settings(testSettings)
+  .settings(
+    libraryDependencies += "io.spray" %% "spray-json" % "1.3.4"
+  )
+lazy val yamlesqueSprayJVM    = yamlesqueSpray.jvm
+lazy val yamlesqueSprayJS     = yamlesqueSpray.js
+lazy val yamlesqueSprayNative = yamlesqueSpray.native
diff --git a/yamlesque-spray/src/main/scala/formats.scala b/yamlesque-spray/src/main/scala/formats.scala
new file mode 100644
index 0000000..4434347
--- /dev/null
+++ b/yamlesque-spray/src/main/scala/formats.scala
@@ -0,0 +1,40 @@
+package yamlesque
+
+import spray.json._
+
+trait JsonYamlFormats {
+
+  implicit def jsonToYamlReader[A](implicit jsReader: JsonReader[A]): YamlReader[A] = new YamlReader[A] {
+    override def read(yaml: YamlValue): A = jsReader.read(JsonFormats.yamlToJson(yaml))
+  }
+
+  implicit def jsonToYamlWriter[A](implicit jsWriter: JsonWriter[A]): YamlWriter[A] = new YamlWriter[A] {
+    override def write(a: A): YamlValue = JsonFormats.jsonToYaml(jsWriter.write(a))
+  }
+
+}
+
+object JsonFormats {
+
+  def jsonToYaml(js: JsValue): YamlValue = js match {
+    case JsNull => YamlScalar.Empty
+    case JsNumber(number) => YamlScalar(number.toString)
+    case JsBoolean(value) => YamlScalar(value.toString)
+    case JsString(value) => YamlScalar(value)
+    case JsArray(elements) => YamlSequence(elements.map(jsonToYaml _ ))
+    case JsObject(fields) => YamlMapping(fields.mapValues(jsonToYaml _ ))
+  }
+
+  val JsNumberPattern = """([-+]?[0-9]*\.?[0-9]+(?:[eE][-+]?[0-9]+)?)""".r
+
+  def yamlToJson(yaml: YamlValue): JsValue = yaml match {
+    case YamlScalar.Empty => JsNull
+    case YamlScalar("true") => JsTrue
+    case YamlScalar("false") => JsFalse
+    case YamlScalar(JsNumberPattern(x)) => JsNumber(x.toDouble)
+    case YamlScalar(x) => JsString(x)
+    case YamlSequence(elements) => JsArray(elements.map(yamlToJson))
+    case YamlMapping(fields) => JsObject(fields.mapValues(yamlToJson))
+  }
+
+}
diff --git a/yamlesque-spray/src/test/scala/FormatTests.scala b/yamlesque-spray/src/test/scala/FormatTests.scala
new file mode 100644
index 0000000..93d763a
--- /dev/null
+++ b/yamlesque-spray/src/test/scala/FormatTests.scala
@@ -0,0 +1,53 @@
+package yamlesque
+
+import spray.json._
+import utest._
+
+object FormatTests extends TestSuite {
+
+  case class A(a1: Int, a2: Seq[B])
+  case class B(a: String, b: Option[Boolean])
+
+  object Protocol extends DefaultJsonProtocol with JsonYamlFormats {
+    implicit def bFormat = jsonFormat2(B)
+    implicit def aFormat = jsonFormat2(A)
+  }
+  import Protocol._
+
+  val tests = Tests {
+    "parse" - {
+      val str =
+        s"""|a1: 42
+            |a2:
+            |  - a: hello world
+            |    b: true
+            |  - a: yoyo
+            |""".stripMargin
+
+      "parse yaml" - {
+        str.parseYaml ==> YamlMapping(
+          "a1" -> YamlScalar("42"),
+          "a2" -> YamlSequence(
+            YamlMapping(
+              "a" -> YamlScalar("hello world"),
+              "b" -> YamlScalar("true")
+            ),
+            YamlMapping(
+              "a" -> YamlScalar("yoyo")
+            )
+          )
+        )
+      }
+      "parse with json readers" - {
+        str.parseYaml.convertTo[A] ==> A(
+          42,
+          Seq(
+            B("hello world", Some(true)),
+            B("yoyo", None),
+          )
+        )
+      }
+    }
+  }
+
+}
diff --git a/yamlesque/src/main/scala/printers.scala b/yamlesque/src/main/scala/YamlPrinter.scala
index 0a1c008..0a1c008 100644
--- a/yamlesque/src/main/scala/printers.scala
+++ b/yamlesque/src/main/scala/YamlPrinter.scala
diff --git a/yamlesque/src/main/scala/formats.scala b/yamlesque/src/main/scala/formats.scala
new file mode 100644
index 0000000..0dbbacc
--- /dev/null
+++ b/yamlesque/src/main/scala/formats.scala
@@ -0,0 +1,8 @@
+package yamlesque
+
+trait YamlReader[A] {
+  def read(yaml: YamlValue): A
+}
+trait YamlWriter[A] {
+  def write(a: A): YamlValue
+}
diff --git a/yamlesque/src/main/scala/package.scala b/yamlesque/src/main/scala/package.scala
index fdb05d0..c40ca70 100644
--- a/yamlesque/src/main/scala/package.scala
+++ b/yamlesque/src/main/scala/package.scala
@@ -1,7 +1,26 @@
 package yamlesque
 
 object `package` {
+
+  def deserializationError(msg: String,
+                           cause: Throwable = null,
+                           fieldNames: List[String] = Nil) =
+    throw new DeserializationException(msg, cause, fieldNames)
+  def serializationError(msg: String) = throw new SerializationException(msg)
+
+  implicit class RichAny[A](val any: A) extends AnyVal {
+    def toYaml(implicit writer: YamlWriter[A]): YamlValue = writer.write(any)
+  }
+
   implicit class RichString(val str: String) extends AnyVal {
     def parseYaml: YamlValue = YamlParser(str.toIterator)
   }
+
 }
+
+case class DeserializationException(msg: String,
+                                    cause: Throwable = null,
+                                    fieldNames: List[String] = Nil)
+    extends RuntimeException(msg, cause)
+
+class SerializationException(msg: String) extends RuntimeException(msg)
diff --git a/yamlesque/src/main/scala/yamlValues.scala b/yamlesque/src/main/scala/yamlValues.scala
index afe8e0b..958fccc 100644
--- a/yamlesque/src/main/scala/yamlValues.scala
+++ b/yamlesque/src/main/scala/yamlValues.scala
@@ -2,6 +2,7 @@ package yamlesque
 
 sealed trait YamlValue {
   def print: String = YamlValue.DefaultPrinter(this)
+  def convertTo[A: YamlReader]: A = implicitly[YamlReader[A]].read(this)
 }
 object YamlValue {
   val DefaultPrinter = new YamlPrinter(compact = true)