JsonFieldEncoder for uuid

zio-json/shared/src/main/scala/zio/json/JsonFieldDecoder.scala

@@ -15,6 +15,8 @@
  */
 package zio.json
 
+import zio.json.uuid.UUIDParser
+
 /** When decoding a JSON Object, we only allow the keys that implement this interface. */
 trait JsonFieldDecoder[+A] {
   self =>
@@ -64,4 +66,22 @@ object JsonFieldDecoder {
         case n: NumberFormatException => Left(s"Invalid Long: '$str': $n")
       }
     }
+
+  implicit val uuid: JsonFieldDecoder[java.util.UUID] = mapStringOrFail { str =>
+    try {
+      Right(UUIDParser.unsafeParse(str))
+    } catch {
+      case iae: IllegalArgumentException => Left(s"Invalid UUID: ${iae.getMessage}")
+    }
+  }
+
+  // use this instead of `string.mapOrFail` in supertypes (to prevent class initialization error at runtime)
+  private[json] def mapStringOrFail[A](f: String => Either[String, A]): JsonFieldDecoder[A] =
+    new JsonFieldDecoder[A] {
+      def unsafeDecodeField(trace: List[JsonError], in: String): A =
+        f(string.unsafeDecodeField(trace, in)) match {
+          case Left(err)    => throw JsonDecoder.UnsafeJson(JsonError.Message(err) :: trace)
+          case Right(value) => value
+        }
+    }
 }

zio-json/shared/src/main/scala/zio/json/JsonFieldEncoder.scala

@@ -38,4 +38,8 @@ object JsonFieldEncoder {
 
   implicit val long: JsonFieldEncoder[Long] =
     JsonFieldEncoder[String].contramap(_.toString)
+
+  implicit val uuid: JsonFieldEncoder[java.util.UUID] =
+    JsonFieldEncoder[String].contramap(_.toString)
+
 }

zio-json/shared/src/test/scala/zio/json/DecoderSpec.scala

@@ -241,6 +241,45 @@ object DecoderSpec extends ZIOSpecDefault {
           val jsonStr  = JsonEncoder[Map[String, String]].encodeJson(expected, None)
           assert(jsonStr.fromJson[Map[String, String]])(isRight(equalTo(expected)))
         },
+        test("Map with UUID keys") {
+          def expectedMap(str: String): Map[UUID, String] = Map(UUID.fromString(str) -> "value")
+
+          val ok1  = """{"64d7c38d-2afd-4514-9832-4e70afe4b0f8": "value"}"""
+          val ok2  = """{"0000000064D7C38D-FD-14-32-70AFE4B0f8": "value"}"""
+          val ok3  = """{"0-0-0-0-0": "value"}"""
+          val bad1 = """{"": "value"}"""
+          val bad2 = """{"64d7c38d-2afd-4514-9832-4e70afe4b0f80": "value"}"""
+          val bad3 = """{"64d7c38d-2afd-4514-983-4e70afe4b0f80": "value"}"""
+          val bad4 = """{"64d7c38d-2afd--9832-4e70afe4b0f8": "value"}"""
+          val bad5 = """{"64d7c38d-2afd-XXXX-9832-4e70afe4b0f8": "value"}"""
+          val bad6 = """{"64d7c38d-2afd-X-9832-4e70afe4b0f8": "value"}"""
+          val bad7 = """{"0-0-0-0-00000000000000000": "value"}"""
+
+          assert(ok1.fromJson[Map[UUID, String]])(
+            isRight(equalTo(expectedMap("64d7c38d-2afd-4514-9832-4e70afe4b0f8")))
+          ) &&
+          assert(ok2.fromJson[Map[UUID, String]])(
+            isRight(equalTo(expectedMap("64D7C38D-00FD-0014-0032-0070AfE4B0f8")))
+          ) &&
+          assert(ok3.fromJson[Map[UUID, String]])(
+            isRight(equalTo(expectedMap("00000000-0000-0000-0000-000000000000")))
+          ) &&
+          assert(bad1.fromJson[Map[UUID, String]])(isLeft(containsString("Invalid UUID: "))) &&
+          assert(bad2.fromJson[Map[UUID, String]])(isLeft(containsString("Invalid UUID: UUID string too large"))) &&
+          assert(bad3.fromJson[Map[UUID, String]])(
+            isLeft(containsString("Invalid UUID: 64d7c38d-2afd-4514-983-4e70afe4b0f80"))
+          ) &&
+          assert(bad4.fromJson[Map[UUID, String]])(
+            isLeft(containsString("Invalid UUID: 64d7c38d-2afd--9832-4e70afe4b0f8"))
+          ) &&
+          assert(bad5.fromJson[Map[UUID, String]])(
+            isLeft(containsString("Invalid UUID: 64d7c38d-2afd-XXXX-9832-4e70afe4b0f8"))
+          ) &&
+          assert(bad6.fromJson[Map[UUID, String]])(
+            isLeft(containsString("Invalid UUID: 64d7c38d-2afd-X-9832-4e70afe4b0f8"))
+          ) &&
+          assert(bad7.fromJson[Map[UUID, String]])(isLeft(containsString("Invalid UUID: 0-0-0-0-00000000000000000")))
+        },
         test("zio.Chunk") {
           val jsonStr  = """["5XL","2XL","XL"]"""
           val expected = Chunk("5XL", "2XL", "XL")

zio-json/shared/src/test/scala/zio/json/EncoderSpec.scala

@@ -261,6 +261,11 @@ object EncoderSpec extends ZIOSpecDefault {
         test("Map, custom keys") {
           assert(Map(1 -> "a").toJson)(equalTo("""{"1":"a"}"""))
         },
+        test("Map, UUID keys") {
+          assert(Map(UUID.fromString("e142f1aa-6e9e-4352-adfe-7e6eb9814ccd") -> "abcd").toJson)(
+            equalTo("""{"e142f1aa-6e9e-4352-adfe-7e6eb9814ccd":"abcd"}""")
+          )
+        },
         test("java.util.UUID") {
           assert(UUID.fromString("e142f1aa-6e9e-4352-adfe-7e6eb9814ccd").toJson)(
             equalTo(""""e142f1aa-6e9e-4352-adfe-7e6eb9814ccd"""")