From e9408391ac874f633aa88c6692da18163d6981fd Mon Sep 17 00:00:00 2001
From: Guntis Smaukstelis <gsmaukstelis@evolution.com>
Date: Wed, 5 Mar 2025 23:25:42 +0200
Subject: [PATCH] Rest api for deleting old forecasts

---
 src/main/scala/data/DataService.scala     | 21 +++++++++++++++++----
 src/main/scala/data/DataServiceTest.scala |  3 ++-
 src/main/scala/server/Server.scala        |  4 +++-
 3 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/src/main/scala/data/DataService.scala b/src/main/scala/data/DataService.scala
index c28a60b..d15b9ba 100644
--- a/src/main/scala/data/DataService.scala
+++ b/src/main/scala/data/DataService.scala
@@ -6,7 +6,10 @@ import cats.effect.kernel.Resource
 import cats.effect.std.Semaphore
 import cats.effect.unsafe.implicits.global
 import cats.implicits._
+import data.DataService.DeletionResult
 import fs2.io.file.{Files, Path}
+import io.circe.Encoder
+import io.circe.generic.semiauto.deriveEncoder
 import org.typelevel.log4cats.Logger
 import org.typelevel.log4cats.slf4j.Slf4jLogger
 import parse.grib.{Grib, GribParser}
@@ -19,6 +22,10 @@ import scala.concurrent.ExecutionContext
 import scala.util.Try
 
 object DataService {
+  case class DeletionResult(fileName: String, success: Boolean, errorMessage: Option[String])
+
+  implicit val deletionResultEncoder: Encoder[DeletionResult] = deriveEncoder[DeletionResult]
+  
   def of: IO[DataService] = {
     for {
       logger <- Slf4jLogger.create[IO]
@@ -107,7 +114,7 @@ class DataService(log: Logger[IO]) {
       }
   }
 
-  def deleteOldForecasts(maxHours: Int = 9): IO[List[String]] = {
+  def deleteOldForecasts(maxHours: Int = 9): IO[List[DeletionResult]] = {
     val nowUTC = ZonedDateTime.now(ZoneOffset.UTC)
     val ageThreshold = nowUTC.minusHours(maxHours)
 
@@ -119,9 +126,15 @@ class DataService(log: Logger[IO]) {
       )
       keepList = fileDateList.filter(_._2.isAfter(ageThreshold)).map(_._1)
       deleteList = fileList.filter(!keepList.contains(_))
-      _ <- deleteList.traverse(name => Files[IO].delete(Path(s"$GRIB_FOLDER/${name}")))
-      _ <- deleteList.traverse(name => log.info(s"delete: $name"))
-    } yield deleteList
+      results <- deleteList.traverse { name =>
+        val path = Path(s"$GRIB_FOLDER/${name}")
+        Files[IO].delete(path).attempt.flatMap {
+          case Right(_) => log.info(s"delete: $name").as(DeletionResult(name, true, None))
+          case Left(error) => log.error(s"Failed to delete $name: ${error.getMessage}")
+            .as(DeletionResult(name, false, Some(error.getMessage)))
+        }
+      }
+    } yield results
   }
 
   private def getTimeFromName(filename: String): Option[(ZonedDateTime, ZonedDateTime)] = {
diff --git a/src/main/scala/data/DataServiceTest.scala b/src/main/scala/data/DataServiceTest.scala
index b5c0128..eb87e9f 100644
--- a/src/main/scala/data/DataServiceTest.scala
+++ b/src/main/scala/data/DataServiceTest.scala
@@ -2,7 +2,8 @@ package data
 
 import cats.effect.IO
 import cats.effect.unsafe.implicits.global
-import io.circe.syntax.EncoderOps
+import data.DataService.deletionResultEncoder
+import io.circe.syntax._
 
 object DataServiceTest {
   def main(args: Array[String]): Unit = {
diff --git a/src/main/scala/server/Server.scala b/src/main/scala/server/Server.scala
index 071f765..f5f10dd 100644
--- a/src/main/scala/server/Server.scala
+++ b/src/main/scala/server/Server.scala
@@ -24,7 +24,6 @@ import parse.csv.Aggregate.{AggregateKey, UserQuery}
 import org.http4s.circe.jsonEncoder
 import org.typelevel.log4cats.Logger
 import org.typelevel.log4cats.slf4j.Slf4jLogger
-import fs2.io.file.Path
 import parse.csv.Aggregate
 
 import scala.concurrent.duration.DurationInt
@@ -68,6 +67,9 @@ class Server(postgresService: PostgresService, dataService: DataService, fetch:
     case GET -> Root / "grib" / "binary-chunk" / ValidateInt(binaryOffset) / ValidateInt(binaryLength) / fileName =>
       dataService.getBinaryChunk(binaryOffset, binaryLength, fileName).flatMap(buffer => Ok(buffer))
 
+    // http://0.0.0.0:8080/api/grib/delete-old-forecasts
+    case GET -> Root / "grib" / "delete-old-forecasts" =>
+      dataService.deleteOldForecasts().flatMap(result => Ok(result.asJson))