com.twitter.scalding.serialization.macros.impl.OrderedBufferableProviderImpl.scala Maven / Gradle / Ivy

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/*
 Copyright 2014 Twitter, Inc.

 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at

 http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 */
package com.twitter.scalding.serialization.macros.impl

import scala.language.experimental.macros
import scala.reflect.macros.Context
import scala.util.Random

import com.twitter.scalding.serialization.OrderedSerialization
import com.twitter.scalding.serialization.macros.impl.ordered_serialization._
import com.twitter.scalding.serialization.macros.impl.ordered_serialization.providers._

object OrderedSerializationProviderImpl {
  def normalizedDispatcher(c: Context)(buildDispatcher: => PartialFunction[c.Type, TreeOrderedBuf[c.type]]): PartialFunction[c.Type, TreeOrderedBuf[c.type]] = {
    case tpe if !(tpe.normalize == tpe) => buildDispatcher(tpe.normalize)
  }

  def scaldingBasicDispatchers(c: Context)(buildDispatcher: => PartialFunction[c.Type, TreeOrderedBuf[c.type]]): PartialFunction[c.Type, TreeOrderedBuf[c.type]] = {

    val primitiveDispatcher = PrimitiveOrderedBuf.dispatch(c)
    val optionDispatcher = OptionOrderedBuf.dispatch(c)(buildDispatcher)
    val eitherDispatcher = EitherOrderedBuf.dispatch(c)(buildDispatcher)
    val caseClassDispatcher = CaseClassOrderedBuf.dispatch(c)(buildDispatcher)
    val caseObjectDispatcher = CaseObjectOrderedBuf.dispatch(c)
    val productDispatcher = ProductOrderedBuf.dispatch(c)(buildDispatcher)
    val stringDispatcher = StringOrderedBuf.dispatch(c)
    val traversablesDispatcher = TraversablesOrderedBuf.dispatch(c)(buildDispatcher)
    val unitDispatcher = UnitOrderedBuf.dispatch(c)
    val byteBufferDispatcher = ByteBufferOrderedBuf.dispatch(c)
    val sealedTraitDispatcher = SealedTraitOrderedBuf.dispatch(c)(buildDispatcher)

    OrderedSerializationProviderImpl.normalizedDispatcher(c)(buildDispatcher)
      .orElse(primitiveDispatcher)
      .orElse(unitDispatcher)
      .orElse(optionDispatcher)
      .orElse(eitherDispatcher)
      .orElse(stringDispatcher)
      .orElse(byteBufferDispatcher)
      .orElse(traversablesDispatcher)
      .orElse(caseClassDispatcher)
      .orElse(caseObjectDispatcher)
      .orElse(productDispatcher)
      .orElse(sealedTraitDispatcher)
  }

  def fallbackImplicitDispatcher(c: Context): PartialFunction[c.Type, TreeOrderedBuf[c.type]] =
    ImplicitOrderedBuf.dispatch(c)

  // Outer dispatcher, do not do implcit for the outermost level, makes no sense there. Should just fail.
  private def outerDispatcher(c: Context): PartialFunction[c.Type, TreeOrderedBuf[c.type]] = {
    import c.universe._
    scaldingBasicDispatchers(c)(OrderedSerializationProviderImpl.innerDispatcher(c)).orElse {
      case tpe: Type => c.abort(c.enclosingPosition, s"""Unable to find OrderedSerialization for type ${tpe}""")
    }
  }

  // Same as the outer dispatcher but we allow an implicit fallback for fields.
  // So in essence it never fails to do a lookup
  private def innerDispatcher(c: Context): PartialFunction[c.Type, TreeOrderedBuf[c.type]] = {
    import c.universe._
    scaldingBasicDispatchers(c)(OrderedSerializationProviderImpl.innerDispatcher(c)).orElse(fallbackImplicitDispatcher(c))
  }

  def apply[T](c: Context)(implicit T: c.WeakTypeTag[T]): c.Expr[OrderedSerialization[T]] = {
    import c.universe._

    val b: TreeOrderedBuf[c.type] = outerDispatcher(c)(T.tpe)
    val res = TreeOrderedBuf.toOrderedSerialization[T](c)(b)
    // println(res)
    res
  }
}