Add potential sketch for scala

design/graph-specification.md

@@ -113,4 +113,107 @@ def phrase_stats_want() -> list[Want[PhraseStats]]:
 ## Rust?
 
 ## Scala?
+```scala
+import databuild._
+import scala.concurrent.duration._
+import java.time.LocalDate
 
+object PodcastReviewsGraph extends DataBuildGraph("//:podcast_reviews_graph") {
+
+  val AllCategories = Set("comedy", ???)
+
+  case class DatePartition(date: String)
+  case class CategoryDatePartition(category: String, date: String)
+  
+  
+  // Partition definitions using extractors
+  object ExtractedReviews extends Partition[DatePartition](
+    """reviews/date=(?P<date>\d{4}-\d{2}-\d{2})""".r
+  )
+
+  object CategorizedReviews extends Partition[CategoryDatePartition](
+    """categorized_reviews/category=(?P<category>[^/]+)/date=(?P<date>\d{4}-\d{2}-\d{2})""".r
+  )
+
+  object PhraseModel extends Partition[CategoryDatePartition](
+    """phrase_models/category=(?P<category>[^/]+)/date=(?P<date>\d{4}-\d{2}-\d{2})""".r
+  )
+
+  object PhraseStats extends Partition[CategoryDatePartition](
+    """phrase_stats/category=(?P<category>[^/]+)/date=(?P<date>\d{4}-\d{2}-\d{2})""".r
+  )
+
+  // Job definitions
+  @job
+  object ExtractReviewsJob extends DataBuildJob[ExtractedReviews] {
+    def config(outputs: List[ExtractedReviews]): List[JobConfig] = {
+      val args = outputs.map(_.date)
+      List(JobConfig(
+        outputs = outputs,
+        inputs = Nil,
+        args = args
+      ))
+    }
+
+    def exec(config: JobConfig): PartitionManifest = {
+      config.args.zip(config.outputs).foreach { case (date, output) =>
+        ingestReviews(date).writeTo(output)
+      }
+      config.toPartitionManifest(this)
+    }
+  }
+
+  @job
+  object CategorizeReviewsJob extends DataBuildJob[CategorizedReviews] {
+    case class Args(date: String, category: String)
+
+    def config(outputs: List[CategorizedReviews]): List[JobConfig] = {
+      outputs.map { p =>
+        ScalaJobConfig[Args](
+          outputs = List(p),
+          inputs = ExtractedReviews.dep.materialize(date = p.date),
+          params = Args(p.date, p.category)
+        )
+      }
+    }
+
+    def exec(config: ScalaJobConfig[Args]): Unit = {
+      categorizeReviews(config.params.date, config.params.category)
+      // Partition manifest auto-constructed
+    }
+  }
+
+  @job
+  object PhraseModelingJob extends DataBuildJob[PhraseModel] {
+    def config(outputs: List[PhraseModel]): List[JobConfig] = {
+      outputs.map { p =>
+        BazelJobConfig(
+          outputs = List(p),
+          inputs = List(CategorizedReviews.dep.materialize(
+            category = p.category,
+            date = p.date
+          )),
+          execTarget = "//jobs:phrase_modeling",
+          env = Map("CATEGORY" -> p.category, "DATA_DATE" -> p.date)
+        )
+      }
+    }
+  }
+
+  // External bazel job
+  bazelJob("//jobs:phrase_stats_job", outputType = classOf[PhraseStats])
+
+  // Want definition
+  @want(cron = "0 0 * * *")
+  def phraseStatsWant(): List[Want[PhraseStats]] = {
+    val today = LocalDate.now().toString
+    val wanted = AllCategories.map(cat => PhraseStats(cat, today)).toList
+
+    List(want(
+      partitions = wanted,
+      ttl = 3.days,
+      onFail = p => s"Failed to calculate partition `$p`"
+    ))
+  }
+}
+```