From 2ba7af01b189358042844dd6077e564799157942 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Germ=C3=A1n=20Calcedo?=
 <49457798+gcalcedo@users.noreply.github.com>
Date: Fri, 20 Sep 2024 14:48:36 +0200
Subject: [PATCH] feat: allow to yield metadata in chat stream (#43)

---
 package.json               | 2 +-
 src/hooks/useChatStream.ts | 8 ++++++++
 src/types.ts               | 2 ++
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 514b1d7..1f3fd93 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@magicul/react-chat-stream",
   "description": "A React hook that lets you easily integrate your custom ChatGPT-like chat in React.",
-  "version": "0.4.0",
+  "version": "0.5.0",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
   "homepage": "https://github.com/XD2Sketch/react-chat-stream#readme",
diff --git a/src/hooks/useChatStream.ts b/src/hooks/useChatStream.ts
index 5e85936..9fb66f6 100644
--- a/src/hooks/useChatStream.ts
+++ b/src/hooks/useChatStream.ts
@@ -41,6 +41,7 @@ const useChatStream = (input: UseChatStreamInput) => {
     const stream = await getStream(message, input.options, input.method);
     const initialMessage = addMessage({ content: '', role: 'bot' });
     let response = '';
+    let metadata = {};
 
     for await (const chunk of decodeStreamToJson(stream)) {
       if (!charactersPerSecond) {
@@ -49,6 +50,13 @@ const useChatStream = (input: UseChatStreamInput) => {
         continue;
       }
 
+      if (input.options.useMetadata) {
+        try {
+          metadata = JSON.parse(chunk.trim());
+          return { ...initialMessage, content: response, metadata: metadata };
+        } catch {}
+      }
+
       // Stream characters one by one based on the characters per second that is set.
       for (const char of chunk) {
         appendMessageToChat(char);
diff --git a/src/types.ts b/src/types.ts
index 25f5ea8..f36a1b5 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -7,6 +7,7 @@ export type UseChatStreamRole = 'bot' | 'user';
 export type UseChatStreamChatMessage = {
   role: UseChatStreamRole;
   content: string;
+  metadata?: {};
   id: string,
 }
 
@@ -17,6 +18,7 @@ export type UseChatStreamOptions = {
   headers?: HeadersInit;
   body?: Record<string, string>;
   fakeCharactersPerSecond?: number;
+  useMetadata?: boolean;
 }
 
 export type UseChatStreamEventHandlers = {