1 files changed, 79 insertions, 0 deletions
diff --git a/scalding/src/main/scala/sandcrawler/Scorable.scala b/scalding/src/main/scala/sandcrawler/Scorable.scala
new file mode 100644
index 0000000..9b9c633
--- /dev/null
+++ b/scalding/src/main/scala/sandcrawler/Scorable.scala
@@ -0,0 +1,79 @@
+package sandcrawler
+
+import scala.math
+import scala.util.parsing.json.JSON
+import scala.util.parsing.json.JSONObject
+
+import cascading.flow.FlowDef
+import com.twitter.scalding._
+import com.twitter.scalding.typed.TDsl._
+
+case class MapFeatures(slug : String, json : String)
+case class ReduceFeatures(json : String)
+case class ReduceOutput(val slug : String,  score : Int, json1 : String, json2 : String)
+
+abstract class Scorable {
+  def getInputPipe(args : Args)(implicit mode : Mode, flowDef : FlowDef) : TypedPipe[(String, ReduceFeatures)] =
+  {
+    getFeaturesPipe(args)
+      .filter { entry => Scorable.isValidSlug(entry.slug) }
+      .groupBy { case MapFeatures(slug, json) => slug }
+      .map { tuple =>
+        val (slug : String, features : MapFeatures) = tuple
+        (slug, ReduceFeatures(features.json))
+      }
+  }
+
+  // abstract methods
+  def getSource(args : Args) : Source
+  def getFeaturesPipe(args : Args)(implicit mode : Mode, flowDef : FlowDef) : TypedPipe[MapFeatures]
+}
+
+object Scorable {
+  val NoSlug = "NO SLUG" // Used for slug if title is empty or unparseable
+
+  def isValidSlug(slug : String) : Boolean = {
+    slug != NoSlug
+  }
+
+  def jsonToMap(json : String) : Option[Map[String, Any]] = {
+    // https://stackoverflow.com/a/32717262/631051
+    val jsonObject = JSON.parseFull(json)
+    if (jsonObject == None) {
+      None
+    } else {
+      Some(jsonObject.get.asInstanceOf[Map[String, Any]])
+    }
+  }
+
+  def getStringOption(optionalMap : Option[Map[String, Any]], key : String) : Option[String] = {
+    optionalMap match {
+      case None => None
+      case Some(map) => if (map contains key) Some(map(key).asInstanceOf[String]) else None
+    }
+  }
+
+  // Caller is responsible for ensuring that key is a String in map.
+  // TODO: Add and handle ClassCastException
+  def getString(map : Map[String, Any], key : String) : String = {
+    assert(map contains key)
+    map(key).asInstanceOf[String]
+  }
+
+  val MaxScore = 1000
+
+  def computeSimilarity(features1 : ReduceFeatures, features2 : ReduceFeatures) : Int = {
+    val json1 = jsonToMap(features1.json)
+    val json2 = jsonToMap(features2.json)
+    getStringOption(json1, "title") match {
+      case None => 0
+      case Some(title1) => {
+        getStringOption(json2, "title") match {
+          case None => 0
+          case Some(title2) =>
+            (StringUtilities.similarity(title1, title2) * MaxScore).toInt
+        }
+      }
+    }
+  }
+}