Feat/function calling (#1503)

* chore: change update to patch

* fix: swagger

* fix: pull api

* chore: refactor server controller

* fix: update status

* feat: mimic openai function calling api with llama3.1

* chore: remove unnecessary cout

* feat: add tool choice option to api

* feat: add unitest

* chore: format code

* feat: function calling in user message

* Update inference_service.cc

---------

Co-authored-by: vansangpfiev <vansangpfiev@gmail.com>

Author: nguyenhoangthuan99

engine/controllers/swagger.cc

@@ -630,10 +630,21 @@ Json::Value SwaggerController::generateOpenAPISpec() {
       "#/components/schemas/ChatMessage";
   schemas["ChatCompletionRequest"]["properties"]["stream"]["type"] = "boolean";
   schemas["ChatCompletionRequest"]["properties"]["engine"]["type"] = "string";
+  schemas["ChatCompletionRequest"]["properties"]["tools"]["type"] = "array";
+  schemas["ChatCompletionRequest"]["properties"]["tools"]["items"]["$ref"] =
+      "#/components/schemas/ToolsCall";
+  schemas["ChatCompletionRequest"]["properties"]["tools_call_in_user_message"]
+         ["type"] = "boolean";
+  schemas["ChatCompletionRequest"]["properties"]["tools_call_in_user_message"]
+         ["default"] = false;
+  schemas["ToolsCall"]["type"] = "object";
 
   schemas["ChatMessage"]["type"] = "object";
   schemas["ChatMessage"]["properties"]["role"]["type"] = "string";
   schemas["ChatMessage"]["properties"]["content"]["type"] = "string";
+  schemas["ChatMessage"]["properties"]["tools"]["type"] = "array";
+  schemas["ChatMessage"]["properties"]["tools"]["items"]["$ref"] =
+      "#/components/schemas/ToolsCall";
 
   schemas["ChatCompletionResponse"]["type"] = "object";
   // Add properties based on your implementation

engine/services/inference_service.cc

@@ -389,4 +389,4 @@ bool InferenceService::HasFieldInReq(std::shared_ptr<Json::Value> json_body,
   }
   return true;
 }
-}  // namespace services
+}  // namespace services

engine/utils/function_calling/common.h

@@ -51,8 +51,9 @@ inline std::string ReplaceCustomFunctions(const std::string& original,
 }
 
 inline bool HasTools(const std::shared_ptr<Json::Value>& request) {
-  return request->isMember("tools") && (*request)["tools"].isArray() &&
-         (*request)["tools"].size() > 0;
+  return (request->isMember("tools") && (*request)["tools"].isArray() &&
+          (*request)["tools"].size() > 0) ||
+         request->get("tools_call_in_user_message", false).asBool();
 }
 
 inline std::string ProcessTools(const std::shared_ptr<Json::Value>& request) {
@@ -149,7 +150,7 @@ inline void UpdateMessages(std::string& system_prompt,
   Json::Value tool_choice = request->get("tool_choice", "auto");
   if (tool_choice.isString() && tool_choice.asString() == "required") {
     system_prompt +=
-        "\n\nYou must use a function to answer the user's question.";
+        "\n\nYou must call a function to answer the user's question.";
   } else if (!tool_choice.isString()) {
 
     system_prompt +=
@@ -158,10 +159,14 @@ inline void UpdateMessages(std::string& system_prompt,
         "' to answer the user's question.";
   }
 
+  bool tools_call_in_user_message =
+      request->get("tools_call_in_user_message", false).asBool();
+
   bool original_stream_config = (*request).get("stream", false).asBool();
   //   (*request)["grammar"] = function_calling_utils::gamma_json;
   (*request)["stream"] =
       false;  //when using function calling, disable stream automatically because we need to parse the response to get function name and params
+
   if (!request->isMember("messages") || !(*request)["messages"].isArray() ||
       (*request)["messages"].empty()) {
     // If no messages, add the system prompt as the first message
@@ -170,21 +175,34 @@ inline void UpdateMessages(std::string& system_prompt,
     systemMessage["content"] = system_prompt;
     (*request)["messages"].append(systemMessage);
   } else {
-    Json::Value& firstMessage = (*request)["messages"][0];
-    if (firstMessage["role"] == "system") {
-      bool addCustomPrompt =
-          request->get("add_custom_system_prompt", true).asBool();
-      if (addCustomPrompt) {
-        firstMessage["content"] =
-            system_prompt + "\n" + firstMessage["content"].asString();
+
+    if (tools_call_in_user_message) {
+      for (Json::Value& message : (*request)["messages"]) {
+        if (message["role"] == "user" && message.isMember("tools") &&
+            message["tools"].isArray() && message["tools"].size() > 0) {
+          message["content"] = system_prompt + "\n User question: " +
+                               message["content"].asString();
+        }
       }
     } else {
-      // If the first message is not a system message, prepend the system prompt
-      Json::Value systemMessage;
-      systemMessage["role"] = "system";
-      systemMessage["content"] = system_prompt;
-      (*request)["messages"].insert(0, systemMessage);
+      Json::Value& firstMessage = (*request)["messages"][0];
+      if (firstMessage["role"] == "system") {
+        bool addCustomPrompt =
+            request->get("add_custom_system_prompt", true).asBool();
+        if (addCustomPrompt) {
+          firstMessage["content"] =
+              system_prompt + "\n" + firstMessage["content"].asString();
+        }
+      } else {
+        // If the first message is not a system message, prepend the system prompt
+        Json::Value systemMessage;
+        systemMessage["role"] = "system";
+        systemMessage["content"] = system_prompt;
+        (*request)["messages"].insert(0, systemMessage);
+      }
     }
+
+    // transform last message role to tool if it is a function call
     Json::Value& lastMessage =
         (*request)["messages"][(*request)["messages"].size() - 1];
     if (lastMessage.get("role", "") == "tool") {