New method "createChatCompletionForFunctions" with an. impl added to OpenAIService{Impl} supporting 'function call' response, for which the model may generate JSON inputs by passing the definition of 'functions' as a param.

Author: peterbanda

openai-client-stream/src/main/scala/io/cequence/openaiscala/service/OpenAIServiceStreamedExtra.scala

@@ -2,7 +2,7 @@ package io.cequence.openaiscala.service
 
 import akka.NotUsed
 import akka.stream.scaladsl.Source
-import io.cequence.openaiscala.domain.MessageSpec
+import io.cequence.openaiscala.domain.{FunctionSpec, MessageSpec}
 import io.cequence.openaiscala.domain.response.{ChatCompletionChunkResponse, ChatCompletionResponse, FineTuneEvent, TextCompletionResponse}
 import io.cequence.openaiscala.domain.settings.{CreateChatCompletionSettings, CreateCompletionSettings}
 
@@ -29,7 +29,7 @@ trait OpenAIServiceStreamedExtra extends OpenAIServiceConsts {
   /**
    * Creates a completion for the chat message(s) with streamed results.
    *
-   * @param messages The messages to generate chat completions.
+   * @param messages A list of messages comprising the conversation so far.
    * @param settings
    * @return chat completion response
    *

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

@@ -1,7 +1,7 @@
 package io.cequence.openaiscala
 
 import io.cequence.openaiscala.JsonUtil.JsonOps
-import io.cequence.openaiscala.domain.ChatRole
+import io.cequence.openaiscala.domain.{ChatRole, FunctionSpec, MessageSpec, FunctionCallSpec}
 
 import java.{util => ju}
 import io.cequence.openaiscala.domain.response._
@@ -29,6 +29,7 @@ object JsonFormats {
         case "user" => JsSuccess(ChatRole.User)
         case "assistant" => JsSuccess(ChatRole.Assistant)
         case "system" => JsSuccess(ChatRole.System)
+        case "function" => JsSuccess(ChatRole.Function)
         case x => JsError(s"$x is not a valid message role.")
       }
     }
@@ -38,6 +39,10 @@ object JsonFormats {
     }
   }
 
+  implicit val messageSpecFormat: Format[MessageSpec] = Json.format[MessageSpec]
+  private implicit val stringAnyMapFormat: Format[Map[String, Any]] = JsonUtil.StringAnyMapFormat
+  implicit val FunctionCallSpec: Format[FunctionCallSpec] = Json.format[FunctionCallSpec]
+  implicit val functionSpecFormat: Format[FunctionSpec] = Json.format[FunctionSpec]
   implicit val chatMessageFormat: Format[ChatMessage] = Json.format[ChatMessage]
   implicit val chatCompletionChoiceInfoFormat: Format[ChatCompletionChoiceInfo] = Json.format[ChatCompletionChoiceInfo]
   implicit val chatCompletionResponseFormat: Format[ChatCompletionResponse] = Json.format[ChatCompletionResponse]

openai-client/src/main/scala/io/cequence/openaiscala/JsonUtil.scala

@@ -95,4 +95,16 @@ object JsonUtil {
       JsObject(fields)
     }
   }
+
+  object StringAnyMapFormat extends Format[Map[String, Any]] {
+    override def reads(json: JsValue): JsResult[Map[String, Any]] = {
+      val resultJsons = json.asSafe[JsObject].fields.map { case (fieldName, jsValue) => (fieldName, jsValue.toString) }
+      JsSuccess(resultJsons.toMap)
+    }
+
+    override def writes(o: Map[String, Any]): JsValue = {
+      val fields = o.map { case (fieldName, value) => (fieldName, toJson(value)) }
+      JsObject(fields)
+    }
+  }
 }

openai-client/src/main/scala/io/cequence/openaiscala/service/Command.scala

@@ -59,4 +59,6 @@ object Tag {
   case object classification_positive_class extends Tag
   case object classification_betas extends Tag
   case object language extends Tag
+  case object functions extends Tag
+  case object function_call extends Tag
 }

openai-client/src/main/scala/io/cequence/openaiscala/service/OpenAIServiceImpl.scala

@@ -9,7 +9,7 @@ import io.cequence.openaiscala.OpenAIScalaClientException
 import io.cequence.openaiscala.domain.settings._
 import io.cequence.openaiscala.domain.response._
 import io.cequence.openaiscala.ConfigImplicits._
-import io.cequence.openaiscala.domain.MessageSpec
+import io.cequence.openaiscala.domain.{FunctionSpec, MessageSpec}
 import io.cequence.openaiscala.service.ws.{Timeouts, WSRequestHelper}
 
 import java.io.File
@@ -116,16 +116,38 @@ private class OpenAIServiceImpl(
       _.asSafe[ChatCompletionResponse]
     )
 
+  override def createChatCompletionForFunctions(
+    messages: Seq[MessageSpec],
+    functions: Seq[FunctionSpec],
+    responseFunctionName: Option[String],
+    settings: CreateChatCompletionSettings
+  ): Future[ChatCompletionResponse] = {
+    val coreParams = createBodyParamsForChatCompletion(messages, settings, stream = false)
+
+    val extraParams = jsonBodyParams(
+      Tag.functions -> Some(Json.toJson(functions)),
+      Tag.function_call -> responseFunctionName.map(name => Map("name" -> name)), // otherwise "auto" is used by default
+    )
+
+    execPOST(
+      Command.chat_completions,
+      bodyParams = coreParams ++ extraParams
+    ).map(
+      _.asSafe[ChatCompletionResponse]
+    )
+  }
+
   protected def createBodyParamsForChatCompletion(
     messages: Seq[MessageSpec],
     settings: CreateChatCompletionSettings,
     stream: Boolean
   ) = {
     assert(messages.nonEmpty, "At least one message expected.")
 
-    val messageJsons = messages.map { case MessageSpec(role, content) =>
-      Json.obj("role" -> role.toString.toLowerCase, "content" -> content)
-    }
+    val messageJsons = messages.map(Json.toJson(_)(messageSpecFormat))
+
+    // case MessageSpec(role, content, name, function_call) =>
+    //      Json.obj("role" -> role.toString.toLowerCase, "content" -> content)
 
     jsonBodyParams(
       Tag.messages -> Some(JsArray(messageJsons)),

openai-core/src/main/scala/io/cequence/openaiscala/service/OpenAIService.scala

@@ -1,6 +1,6 @@
 package io.cequence.openaiscala.service
 
-import io.cequence.openaiscala.domain.MessageSpec
+import io.cequence.openaiscala.domain.{FunctionSpec, MessageSpec}
 import io.cequence.openaiscala.domain.settings._
 import io.cequence.openaiscala.domain.response._
 
@@ -61,19 +61,36 @@ trait OpenAIService extends OpenAIServiceConsts {
   ): Future[TextCompletionResponse]
 
   /**
-   * Creates a completion for the chat message(s).
+   * Creates a model response for the given chat conversation.
    *
-   * @param messages The messages to generate chat completions.
+   * @param messages A list of messages comprising the conversation so far.
    * @param settings
    * @return chat completion response
-   *
    * @see <a href="https://platform.openai.com/docs/api-reference/chat/create">OpenAI Doc</a>
    */
   def createChatCompletion(
     messages: Seq[MessageSpec],
     settings: CreateChatCompletionSettings = DefaultSettings.CreateChatCompletion
   ): Future[ChatCompletionResponse]
 
+  /**
+   * Creates a model response for the given chat conversation expecting a function call.
+   *
+   * @param messages             A list of messages comprising the conversation so far.
+   * @param functions            A list of functions the model may generate JSON inputs for.
+   * @param responseFunctionName If specified it forces the model to respond with a call to that function (must be listed in `functions`).
+   *                             Otherwise, the default "auto" mode is used where the model can pick between an end-user or calling a function.
+   * @param settings
+   * @return chat completion response
+   * @see <a href="https://platform.openai.com/docs/api-reference/chat/create">OpenAI Doc</a>
+   */
+  def createChatCompletionForFunctions(
+    messages: Seq[MessageSpec],
+    functions: Seq[FunctionSpec],
+    responseFunctionName: Option[String] = None,
+    settings: CreateChatCompletionSettings = DefaultSettings.CreateChatCompletionForFunctions
+  ): Future[ChatCompletionResponse]
+
   /**
    * Creates a new edit for the provided input, instruction, and parameters.
    *

openai-core/src/main/scala/io/cequence/openaiscala/service/OpenAIServiceConsts.scala

@@ -31,6 +31,11 @@ trait OpenAIServiceConsts {
       max_tokens = Some(1000)
     )
 
+    val CreateChatCompletionForFunctions = CreateChatCompletionSettings(
+      model = ModelId.gpt_3_5_turbo_0613,
+      max_tokens = Some(1000)
+    )
+
     val CreateEdit = CreateEditSettings(
       model = ModelId.text_davinci_edit_001,
       temperature = Some(0.7)

openai-core/src/main/scala/io/cequence/openaiscala/service/OpenAIServiceWrapper.scala

@@ -1,6 +1,6 @@
 package io.cequence.openaiscala.service
 
-import io.cequence.openaiscala.domain.MessageSpec
+import io.cequence.openaiscala.domain.{FunctionSpec, MessageSpec}
 import io.cequence.openaiscala.domain.settings._
 
 import java.io.File
@@ -33,6 +33,15 @@ trait OpenAIServiceWrapper extends OpenAIService {
     _.createChatCompletion(messages, settings)
   )
 
+  override def createChatCompletionForFunctions(
+    messages: Seq[MessageSpec],
+    functions: Seq[FunctionSpec],
+    responseFunctionName: Option[String],
+    settings: CreateChatCompletionSettings
+  ) = wrap(
+    _.createChatCompletion(messages, settings)
+  )
+
   override def createEdit(
     input: String,
     instruction: String,