Ianoc/case class tuple converters

project/Build.scala

@@ -24,7 +24,7 @@ object ScaldingBuild extends Build {
   val scalaCheckVersion = "1.11.5"
   val hadoopVersion = "1.2.1"
   val algebirdVersion = "0.8.2"
-  val bijectionVersion = "0.7.0"
+  val bijectionVersion = "0.7.1"
   val chillVersion = "0.5.1"
   val slf4jVersion = "1.6.6"
   val parquetVersion = "1.6.0rc4"
@@ -200,6 +200,7 @@ object ScaldingBuild extends Build {
     scaldingJson,
     scaldingJdbc,
     scaldingHadoopTest,
+    scaldingMacros,
     maple
   )
 
@@ -401,6 +402,16 @@ object ScaldingBuild extends Build {
     }
   ).dependsOn(scaldingCore)
 
+  lazy val scaldingMacros = module("macros").settings(
+    libraryDependencies <++= (scalaVersion) { scalaVersion => Seq(
+      "org.scala-lang" % "scala-library" % scalaVersion,
+      "org.scala-lang" % "scala-reflect" % scalaVersion,
+      "com.twitter" %% "bijection-macros" % bijectionVersion
+    ) ++ (if(isScala210x(scalaVersion)) Seq("org.scalamacros" %% "quasiquotes" % "2.0.1") else Seq())
+  },
+  addCompilerPlugin("org.scalamacros" % "paradise" % "2.0.1" cross CrossVersion.full)
+  ).dependsOn(scaldingCore, scaldingHadoopTest)
+
   // This one uses a different naming convention
   lazy val maple = Project(
     id = "maple",

scalding-macros/src/main/scala/com/twitter/scalding/macros/MacroImplicits.scala

@@ -0,0 +1,15 @@
+package com.twitter.scalding.macros
+
+import scala.language.experimental.macros
+
+import com.twitter.scalding._
+import com.twitter.scalding.macros.impl.MacroImpl
+import com.twitter.bijection.macros.IsCaseClass
+
+object MacroImplicits {
+  /**
+   * This method provides proof that the given type is a case class.
+   */
+  implicit def materializeCaseClassTupleSetter[T: IsCaseClass]: TupleSetter[T] = macro MacroImpl.caseClassTupleSetterImpl[T]
+  implicit def materializeCaseClassTupleConverter[T: IsCaseClass]: TupleConverter[T] = macro MacroImpl.caseClassTupleConverterImpl[T]
+}

scalding-macros/src/main/scala/com/twitter/scalding/macros/Macros.scala

@@ -0,0 +1,14 @@
+package com.twitter.scalding.macros
+
+import scala.language.experimental.macros
+
+import com.twitter.scalding._
+import com.twitter.scalding.macros.impl.MacroImpl
+import com.twitter.bijection.macros.IsCaseClass
+
+object Macros {
+  // These only work for simple types inside the case class
+  // Nested case classes are allowed, but only: Int, Boolean, String, Long, Short, Float, Double of other types are allowed
+  def caseClassTupleSetter[T: IsCaseClass]: TupleSetter[T] = macro MacroImpl.caseClassTupleSetterImpl[T]
+  def caseClassTupleConverter[T: IsCaseClass]: TupleConverter[T] = macro MacroImpl.caseClassTupleConverterImpl[T]
+}

scalding-macros/src/main/scala/com/twitter/scalding/macros/impl/MacroImpl.scala

@@ -0,0 +1,141 @@
+package com.twitter.scalding.macros.impl
+
+import scala.collection.mutable.{ Map => MMap }
+import scala.language.experimental.macros
+import scala.reflect.macros.Context
+import scala.reflect.runtime.universe._
+import scala.util.{ Try => BasicTry }
+
+import cascading.tuple.{ Tuple, TupleEntry }
+
+import com.twitter.scalding._
+import com.twitter.bijection.macros.{ IsCaseClass, MacroGenerated }
+import com.twitter.bijection.macros.impl.IsCaseClassImpl
+/**
+ * This class contains the core macro implementations. This is in a separate module to allow it to be in
+ * a separate compilation unit, which makes it easier to provide helper methods interfacing with macros.
+ */
+object MacroImpl {
+  def caseClassTupleSetterNoProof[T]: TupleSetter[T] = macro caseClassTupleSetterNoProofImpl[T]
+
+  def caseClassTupleSetterImpl[T](c: Context)(proof: c.Expr[IsCaseClass[T]])(implicit T: c.WeakTypeTag[T]): c.Expr[TupleSetter[T]] =
+    caseClassTupleSetterNoProofImpl(c)(T)
+
+  def caseClassTupleSetterNoProofImpl[T](c: Context)(implicit T: c.WeakTypeTag[T]): c.Expr[TupleSetter[T]] = {
+    import c.universe._
+    //TODO get rid of the mutability
+    val cachedTupleSetters: MMap[Type, Int] = MMap.empty
+    var cacheIdx = 0
+
+    def expandMethod(outerTpe: Type, pTree: Tree): Iterable[Int => Tree] = {
+      outerTpe
+        .declarations
+        .collect { case m: MethodSymbol if m.isCaseAccessor => m }
+        .flatMap { accessorMethod =>
+          accessorMethod.returnType match {
+            case tpe if tpe =:= typeOf[String] => List((idx: Int) => q"""tup.setString(${idx}, $pTree.$accessorMethod)""")
+            case tpe if tpe =:= typeOf[Boolean] => List((idx: Int) => q"""tup.setBoolean(${idx}, $pTree.$accessorMethod)""")
+            case tpe if tpe =:= typeOf[Short] => List((idx: Int) => q"""tup.setShort(${idx}, $pTree.$accessorMethod)""")
+            case tpe if tpe =:= typeOf[Int] => List((idx: Int) => q"""tup.setInteger(${idx}, $pTree.$accessorMethod)""")
+            case tpe if tpe =:= typeOf[Long] => List((idx: Int) => q"""tup.setLong(${idx}, $pTree.$accessorMethod)""")
+            case tpe if tpe =:= typeOf[Float] => List((idx: Int) => q"""tup.setFloat(${idx}, $pTree.$accessorMethod)""")
+            case tpe if tpe =:= typeOf[Double] => List((idx: Int) => q"""tup.setDouble(${idx}, $pTree.$accessorMethod)""")
+            case tpe if IsCaseClassImpl.isCaseClassType(c)(tpe) =>
+              expandMethod(tpe,
+                q"""$pTree.$accessorMethod""")
+            case _ => c.abort(c.enclosingPosition, s"Case class ${T} is not pure primitives or nested case classes")
+          }
+        }
+    }
+
+    val set =
+      expandMethod(T.tpe, q"t")
+        .zipWithIndex
+        .map {
+          case (treeGenerator, idx) =>
+            treeGenerator(idx)
+        }
+
+    val res = q"""
+    new _root_.com.twitter.scalding.TupleSetter[$T] with _root_.com.twitter.bijection.macros.MacroGenerated {
+      override def apply(t: $T): _root_.cascading.tuple.Tuple = {
+        val tup = _root_.cascading.tuple.Tuple.size(${set.size})
+        ..$set
+        tup
+      }
+      override val arity: scala.Int = ${set.size}
+    }
+    """
+    c.Expr[TupleSetter[T]](res)
+  }
+
+  def caseClassTupleConverterNoProof[T]: TupleConverter[T] = macro caseClassTupleConverterNoProofImpl[T]
+
+  def caseClassTupleConverterImpl[T](c: Context)(proof: c.Expr[IsCaseClass[T]])(implicit T: c.WeakTypeTag[T]): c.Expr[TupleConverter[T]] =
+    caseClassTupleConverterNoProofImpl(c)(T)
+
+  def caseClassTupleConverterNoProofImpl[T](c: Context)(implicit T: c.WeakTypeTag[T]): c.Expr[TupleConverter[T]] = {
+    import c.universe._
+    //TODO get rid of the mutability
+    val cachedTupleConverters: MMap[Type, Int] = MMap.empty
+    var cacheIdx = 0
+    case class AccessorBuilder(builder: Tree, size: Int)
+
+    def getPrimitive(strAccessor: Tree): Int => AccessorBuilder =
+      { (idx: Int) =>
+        AccessorBuilder(q"""${strAccessor}(${idx})""", 1)
+      }
+
+    def flattenAccessorBuilders(tpe: Type, idx: Int, childGetters: List[(Int => AccessorBuilder)]): AccessorBuilder = {
+      val (_, accessors) = childGetters.foldLeft((idx, List[AccessorBuilder]())) {
+        case ((curIdx, eles), t) =>
+          val nextEle = t(curIdx)
+          val idxIncr = nextEle.size
+          (curIdx + idxIncr, eles :+ nextEle)
+      }
+
+      val builder = q"""
+        ${tpe.typeSymbol.companionSymbol}(..${accessors.map(_.builder)})
+      """
+      val size = accessors.map(_.size).reduce(_ + _)
+      AccessorBuilder(builder, size)
+    }
+
+    def expandMethod(outerTpe: Type): List[(Int => AccessorBuilder)] = {
+      outerTpe.declarations
+        .collect { case m: MethodSymbol if m.isCaseAccessor => m.returnType }
+        .toList
+        .map { accessorMethod =>
+          accessorMethod match {
+            case tpe if tpe =:= typeOf[String] => getPrimitive(q"t.getString")
+            case tpe if tpe =:= typeOf[Boolean] => getPrimitive(q"t.Boolean")
+            case tpe if tpe =:= typeOf[Short] => getPrimitive(q"t.getShort")
+            case tpe if tpe =:= typeOf[Int] => getPrimitive(q"t.getInteger")
+            case tpe if tpe =:= typeOf[Long] => getPrimitive(q"t.getLong")
+            case tpe if tpe =:= typeOf[Float] => getPrimitive(q"t.getFloat")
+            case tpe if tpe =:= typeOf[Double] => getPrimitive(q"t.getDouble")
+            case tpe if IsCaseClassImpl.isCaseClassType(c)(tpe) =>
+              { (idx: Int) =>
+                {
+                  val childGetters = expandMethod(tpe)
+                  flattenAccessorBuilders(tpe, idx, childGetters)
+                }
+              }
+            case _ => c.abort(c.enclosingPosition, s"Case class ${T} is not pure primitives or nested case classes")
+          }
+        }
+    }
+
+    val accessorBuilders = flattenAccessorBuilders(T.tpe, 0, expandMethod(T.tpe))
+
+    val res = q"""
+    new _root_.com.twitter.scalding.TupleConverter[$T] with _root_.com.twitter.bijection.macros.MacroGenerated {
+     override def apply(t: _root_.cascading.tuple.TupleEntry): $T = {
+        ${accessorBuilders.builder}
+      }
+      override val arity: scala.Int = ${accessorBuilders.size}
+    }
+    """
+    c.Expr[TupleConverter[T]](res)
+  }
+}

scalding-macros/src/test/scala/com/twitter/scalding/macros/MacroDepHygiene.scala

@@ -0,0 +1,56 @@
+package com.twitter.scalding.macros
+
+import org.scalatest.WordSpec
+import com.twitter.scalding.macros.{ _ => _ }
+
+/**
+ * This test is intended to ensure that the macros do not require any imported code in scope. This is why all
+ * references are via absolute paths.
+ */
+class MacroDepHygiene extends WordSpec {
+  import com.twitter.bijection.macros.impl.IsCaseClassImpl
+
+  case class A(x: Int, y: String)
+  case class B(x: A, y: String, z: A)
+  class C
+
+  def isMg(a: Any) = a.isInstanceOf[com.twitter.bijection.macros.MacroGenerated]
+
+  "TupleSetter macro" should {
+    def isTupleSetterAvailable[T](implicit proof: com.twitter.scalding.TupleSetter[T]) = isMg(proof)
+
+    "work fine without any imports" in {
+      com.twitter.scalding.macros.Macros.caseClassTupleSetter[A]
+      com.twitter.scalding.macros.Macros.caseClassTupleSetter[B]
+    }
+
+    "implicitly work fine without any imports" in {
+      import com.twitter.scalding.macros.MacroImplicits.materializeCaseClassTupleSetter
+      assert(isTupleSetterAvailable[A])
+      assert(isTupleSetterAvailable[B])
+    }
+
+    "fail if not a case class" in {
+      assert(!isTupleSetterAvailable[C])
+    }
+  }
+
+  "TupleConverter macro" should {
+    def isTupleConverterAvailable[T](implicit proof: com.twitter.scalding.TupleConverter[T]) = isMg(proof)
+
+    "work fine without any imports" in {
+      com.twitter.scalding.macros.Macros.caseClassTupleConverter[A]
+      com.twitter.scalding.macros.Macros.caseClassTupleConverter[B]
+    }
+
+    "implicitly work fine without any imports" in {
+      import com.twitter.scalding.macros.MacroImplicits.materializeCaseClassTupleConverter
+      assert(isTupleConverterAvailable[A])
+      assert(isTupleConverterAvailable[B])
+    }
+
+    "fail if not a case class" in {
+      assert(!isTupleConverterAvailable[C])
+    }
+  }
+}

scalding-macros/src/test/scala/com/twitter/scalding/macros/MacrosUnitTests.scala

@@ -0,0 +1,126 @@
+package com.twitter.scalding.macros
+
+import cascading.tuple.{ Tuple => CTuple, TupleEntry }
+
+import org.scalatest.{ Matchers, WordSpec }
+
+import com.twitter.scalding._
+import com.twitter.scalding.macros._
+import com.twitter.scalding.macros.impl._
+import com.twitter.scalding.serialization.Externalizer
+
+import com.twitter.bijection.macros.{ IsCaseClass, MacroGenerated }
+
+// We avoid nesting these just to avoid any complications in the serialization test
+case class SampleClassA(x: Int, y: String)
+case class SampleClassB(a1: SampleClassA, a2: SampleClassA, y: String)
+case class SampleClassC(a: SampleClassA, b: SampleClassB, c: SampleClassA, d: SampleClassB, e: SampleClassB)
+
+class MacrosUnitTests extends WordSpec with Matchers {
+  import MacroImplicits._
+  def isMg[T](t: T): T = {
+    t shouldBe a[MacroGenerated]
+    t
+  }
+
+  def mgConv[T](te: TupleEntry)(implicit conv: TupleConverter[T]): T = isMg(conv)(te)
+  def mgSet[T](t: T)(implicit set: TupleSetter[T]): TupleEntry = new TupleEntry(isMg(set)(t))
+
+  def shouldRoundTrip[T: IsCaseClass: TupleSetter: TupleConverter](t: T) {
+    t shouldBe mgConv(mgSet(t))
+  }
+
+  def shouldRoundTripOther[T: IsCaseClass: TupleSetter: TupleConverter](te: TupleEntry, t: T) {
+    val inter = mgConv(te)
+    inter shouldBe t
+    mgSet(inter) shouldBe te
+  }
+
+  def canExternalize(t: AnyRef) { Externalizer(t).javaWorks shouldBe true }
+
+  "MacroGenerated TupleSetter" should {
+    def doesJavaWork[T](implicit set: TupleSetter[T]) { canExternalize(isMg(set)) }
+    "be serializable for case class A" in { doesJavaWork[SampleClassA] }
+    "be serializable for case class B" in { doesJavaWork[SampleClassB] }
+    "be serializable for case class C" in { doesJavaWork[SampleClassC] }
+  }
+
+  "MacroGenerated TupleConverter" should {
+    def doesJavaWork[T](implicit conv: TupleConverter[T]) { canExternalize(isMg(conv)) }
+    "be serializable for case class A" in { doesJavaWork[SampleClassA] }
+    "be serializable for case class B" in { doesJavaWork[SampleClassB] }
+    "be serializable for case class C" in { doesJavaWork[SampleClassC] }
+  }
+
+  "MacroGenerated TupleSetter and TupleConverter" should {
+    "round trip class -> tupleentry -> class" in {
+      shouldRoundTrip(SampleClassA(100, "onehundred"))
+      shouldRoundTrip(SampleClassB(SampleClassA(100, "onehundred"), SampleClassA(-1, "zero"), "what"))
+      val a = SampleClassA(73, "hrm")
+      val b = SampleClassB(a, a, "hrm")
+      shouldRoundTrip(b)
+      shouldRoundTrip(SampleClassC(a, b, SampleClassA(123980, "hey"), SampleClassB(a, SampleClassA(-1, "zero"), "zoo"), b))
+    }
+
+    "Case Class should form expected tuple" in {
+      val input = SampleClassC(SampleClassA(1, "asdf"),
+        SampleClassB(SampleClassA(2, "bcdf"), SampleClassA(5, "jkfs"), "wetew"),
+        SampleClassA(9, "xcmv"),
+        SampleClassB(SampleClassA(23, "ck"), SampleClassA(13, "dafk"), "xcv"),
+        SampleClassB(SampleClassA(34, "were"), SampleClassA(654, "power"), "adsfmx"))
+      val setter = implicitly[TupleSetter[SampleClassC]]
+      val tup = setter(input)
+      assert(tup.size == 19)
+      assert(tup.get(0) === 1)
+      assert(tup.get(18) === "adsfmx")
+    }
+
+    "round trip tupleentry -> class -> tupleEntry" in {
+      val a_tup = CTuple.size(2)
+      a_tup.setInteger(0, 100)
+      a_tup.setString(1, "onehundred")
+      val a_te = new TupleEntry(a_tup)
+      val a = SampleClassA(100, "onehundred")
+      shouldRoundTripOther(a_te, a)
+
+      val b_tup = CTuple.size(5)
+      b_tup.setInteger(0, 100)
+      b_tup.setString(1, "onehundred")
+      b_tup.setInteger(2, 100)
+      b_tup.setString(3, "onehundred")
+      b_tup.setString(4, "what")
+      val b_te = new TupleEntry(b_tup)
+      val b = SampleClassB(a, a, "what")
+      shouldRoundTripOther(b_te, b)
+
+      val c_tup = CTuple.size(19)
+      c_tup.setInteger(0, 100)
+      c_tup.setString(1, "onehundred")
+
+      c_tup.setInteger(2, 100)
+      c_tup.setString(3, "onehundred")
+      c_tup.setInteger(4, 100)
+      c_tup.setString(5, "onehundred")
+      c_tup.setString(6, "what")
+
+      c_tup.setInteger(7, 100)
+      c_tup.setString(8, "onehundred")
+
+      c_tup.setInteger(9, 100)
+      c_tup.setString(10, "onehundred")
+      c_tup.setInteger(11, 100)
+      c_tup.setString(12, "onehundred")
+      c_tup.setString(13, "what")
+
+      c_tup.setInteger(14, 100)
+      c_tup.setString(15, "onehundred")
+      c_tup.setInteger(16, 100)
+      c_tup.setString(17, "onehundred")
+      c_tup.setString(18, "what")
+
+      val c_te = new TupleEntry(c_tup)
+      val c = SampleClassC(a, b, a, b, b)
+      shouldRoundTripOther(c_te, c)
+    }
+  }
+}