Core - hasType trait and json format

Author: peterbanda

openai-core/src/main/scala/io/cequence/openaiscala/JsonFormats.scala

@@ -27,7 +27,7 @@ import io.cequence.openaiscala.domain.response.ResponseFormat.{
   TextResponse
 }
 import io.cequence.openaiscala.domain.response._
-import io.cequence.openaiscala.domain.{ThreadMessageFile, _}
+import io.cequence.openaiscala.domain.{HasType, ThreadMessageFile, _}
 import io.cequence.wsclient.JsonUtil
 import io.cequence.wsclient.JsonUtil.{enumFormat, snakeEnumFormat}
 import play.api.libs.functional.syntax._
@@ -1385,4 +1385,18 @@ object JsonFormats {
     Format(eitherJsonSchemaReads, eitherJsonSchemaWrites)
 
   implicit val jsonSchemaDefFormat: Format[JsonSchemaDef] = Json.format[JsonSchemaDef]
+
+  /**
+   * Wraps an OFormat with type field handling for classes extending HasType. Automatically
+   * adds the `type` field during serialization and validates it during deserialization.
+   *
+   * @param format
+   *   The underlying OFormat to wrap
+   * @tparam T
+   *   The type extending HasType
+   * @return
+   *   A Format that handles type field serialization and validation
+   */
+  def formatWithType[T <: HasType](format: OFormat[T]): OFormat[T] =
+    TypeJsonWrapper(format)
 }

openai-core/src/main/scala/io/cequence/openaiscala/TypeJsonWrapper.scala

@@ -0,0 +1,31 @@
+package io.cequence.openaiscala
+
+import io.cequence.openaiscala.domain.HasType
+import play.api.libs.json.{Format, JsError, JsObject, JsResult, JsSuccess, JsValue, Json, OFormat}
+
+private class TypeJsonWrapper[T <: HasType](val format: OFormat[T]) extends OFormat[T] {
+  override def reads(json: JsValue): JsResult[T] = {
+    // First read using the underlying format
+    format.reads(json).flatMap { obj =>
+      // Validate that the type field in JSON matches the object's type
+      (json \ "type").asOpt[String] match {
+        case Some(jsonType) if jsonType == obj.`type`.toString =>
+          JsSuccess(obj)
+        case Some(jsonType) =>
+          JsError(s"Type mismatch: expected ${obj.`type`.toString}, got $jsonType")
+        case None =>
+          JsError("Missing type field")
+      }
+    }
+  }
+
+  override def writes(o: T): JsObject = {
+    // Write using the underlying format, then add type field
+    val json = format.writes(o)
+    json ++ Json.obj("type" -> o.`type`.toString)
+  }
+}
+
+object TypeJsonWrapper {
+  def apply[T <: HasType](format: OFormat[T]): OFormat[T] = new TypeJsonWrapper(format)
+}

openai-core/src/main/scala/io/cequence/openaiscala/domain/HasType.scala

@@ -0,0 +1,5 @@
+package io.cequence.openaiscala.domain
+
+trait HasType {
+  val `type`: Any
+}