Implement FileFetchScheduler and refactor Main class

src/main/scala/fetch/FileFetchScheduler.scala

@@ -0,0 +1,29 @@
+package fetch
+
+import cats.effect.IO
+import db.DBService
+import fs2.Stream
+import org.typelevel.log4cats.Logger
+import org.typelevel.log4cats.slf4j.Slf4jLogger
+
+
+object FileFetchScheduler {
+  def of(dbService: DBService): IO[FileFetchScheduler] = {
+    Slf4jLogger.create[IO].map {
+      new FileFetchScheduler(dbService, _)
+    }
+  }
+}
+class FileFetchScheduler(dbService: DBService, log: Logger[IO]) {
+  def run: Stream[IO, Unit] = {
+    val fetchTask = FileNameService.generateCurrentHour.flatMap(FetchService.fetchSingleFile)
+    Scheduler.scheduleTask(fetchTask)
+      .evalMap { case (name, content) =>
+        log.info(s"fetched: $name") *>
+          dbService.save(name, content).attempt.flatMap {
+            case Right(savedName) => log.info(s"saved: $savedName")
+            case Left(err) => log.error(s"error: $err")
+          }
+      }
+  }
+}