[SCALA-352] - Error handling in ZIO

zio/src/main/scala-2/com/baeldung/scala/zio/errorhandling/ErrorHandling.scala

@@ -0,0 +1,63 @@
+package com.baeldung.scala.zio.errorhandling
+
+import zio.{Schedule, ZIO}
+
+import java.io.IOException
+
+object ErrorHandling {
+
+  private def stubbedResource(
+    isFail: Boolean = false
+  ): ZIO[Any, IOException, String] = {
+    if (isFail) ZIO.fail(new IOException()) else ZIO.succeed("success")
+  }
+
+  def usingEither: ZIO[Any, Nothing, Either[IOException, String]] = {
+    stubbedResource().either
+  }
+
+  def usingOrElse: ZIO[Any, IOException, String] = {
+    stubbedResource(true).orElse(stubbedResource(false))
+  }
+
+  def usingCatchAll: ZIO[Any, IOException, String] = {
+    stubbedResource(true).catchAll(_ =>
+      for {
+        _ <- ZIO.logError("Some error occurred")
+        resource <- stubbedResource(false)
+      } yield resource
+    )
+  }
+
+  def usingCatchSome: ZIO[Any, IOException, String] = {
+    stubbedResource(true).catchSome { case _: IOException =>
+      ZIO.logError("Some error occurred")
+      stubbedResource(false)
+    }
+  }
+
+  def usingFold: ZIO[Any, Nothing, String] = {
+    stubbedResource(true).fold(
+      fail => "some default",
+      success => success
+    )
+  }
+
+  def usingFoldZIO: ZIO[Any, IOException, String] = {
+    stubbedResource(true).foldZIO(
+      fail => stubbedResource(false),
+      success => ZIO.succeed(success)
+    )
+  }
+
+  def usingRetry: ZIO[Any, IOException, String] = {
+    stubbedResource(true).retry(Schedule.recurs(3))
+  }
+
+  def usingRetryOrElse: ZIO[Any, IOException, String] = {
+    stubbedResource(true).retryOrElse(
+      Schedule.recurs(3),
+      (_, _: Long) => stubbedResource(false)
+    )
+  }
+}

zio/src/test/scala-2/com/baeldung/scala/zio/errorhandling/ErrorHandlingSpec.scala

@@ -0,0 +1,54 @@
+package com.baeldung.scala.zio.errorhandling
+
+import zio.{Scope, ZIO}
+import zio.test.{Spec, TestEnvironment, ZIOSpecDefault}
+import zio.test._
+
+object ErrorHandlingSpec extends ZIOSpecDefault {
+  val successResult = "success"
+  override def spec: Spec[TestEnvironment with Scope, Any] =
+    suite("ErrorHandlingSpec")(
+      test("usingEither returns Either of String") {
+        for {
+          result <- ErrorHandling.usingEither
+        } yield assertTrue(result == Right(successResult))
+      },
+      test("usingOrElse returns success") {
+        for {
+          result <- ErrorHandling.usingOrElse
+        } yield assertTrue(result == successResult)
+      },
+      test("usingCatchAll returns success") {
+        for {
+          result <- ErrorHandling.usingCatchAll
+        } yield assertTrue(result == successResult)
+      },
+      test("usingCatchSome returns success") {
+        for {
+          result <- ErrorHandling.usingCatchSome
+        } yield assertTrue(result == successResult)
+      },
+      test("usingFold returns default") {
+        for {
+          result <- ErrorHandling.usingFold
+        } yield assertTrue(result == "some default")
+      },
+      test("usingFoldZIO returns success") {
+        for {
+          result <- ErrorHandling.usingFoldZIO
+        } yield assertTrue(result == successResult)
+      },
+      test("usingRetry returns an IOException") {
+        val failureResult =
+          ErrorHandling.usingRetryOrElse.catchAll(ZIO.succeed(_))
+        for {
+          error <- failureResult
+        } yield assertTrue(error == error)
+      },
+      test("usingRetryOrElse returns success") {
+        for {
+          result <- ErrorHandling.usingRetryOrElse
+        } yield assertTrue(result == successResult)
+      }
+    )
+}