📦 NEW: Add branching example

Author: saqibameen

examples/nodejs/threads/threads.branch.ts

@@ -0,0 +1,108 @@
+import dotenv from 'dotenv';
+import {Langbase, ThreadMessage} from 'langbase';
+
+dotenv.config();
+
+const langbase = new Langbase({
+	apiKey: process.env.LANGBASE_API_KEY!,
+});
+
+// Helper to create initial conversation
+async function createConversation() {
+	const thread = await langbase.threads.create({
+		messages: [
+			{
+				role: 'user',
+				content: 'I need to add state management to my React app',
+			},
+			{
+				role: 'assistant',
+				content:
+					'I can help you with state management in React. How complex is your app \
+					and what are your main requirements?',
+			},
+			{
+				role: 'user',
+				content:
+					"It's a medium-sized app with user data, API calls, and real-time updates",
+			},
+			{
+				role: 'assistant',
+				content:
+					'For your needs, you could use Redux for its mature ecosystem, or Zustand \
+					for a simpler, more modern approach. Which direction interests you?',
+			},
+		],
+	});
+
+	return thread.id;
+}
+
+// Branch thread at decision point
+async function branchThread(threadId: string, branchAt: number) {
+	// Get all messages
+	const messages = await langbase.threads.messages.list({threadId});
+
+	// Take messages up to branch point
+	const messagesToKeep = messages.slice(0, branchAt);
+
+	// Create new thread with selected messages
+	const branch = await langbase.threads.create({
+		messages: messagesToKeep as ThreadMessage[],
+		metadata: {
+			parent: threadId,
+			branchedAt: branchAt.toString(),
+		},
+	});
+
+	return branch.id;
+}
+
+async function main() {
+	// Create original conversation
+	const originalId = await createConversation();
+
+	// Branch at decision point (after state management options presented)
+	const branchId = await branchThread(originalId, 4);
+
+	// Continue original thread with Redux
+	await langbase.threads.append({
+		threadId: originalId,
+		messages: [
+			{role: 'user', content: "Let's go with Redux"},
+			{
+				role: 'assistant',
+				content:
+					'Great choice for a robust solution! Redux with Redux Toolkit makes it \
+					much easier. Let me show you the setup...',
+			},
+		],
+	});
+
+	// Branch explores Zustand
+	await langbase.threads.append({
+		threadId: branchId,
+		messages: [
+			{role: 'user', content: 'Tell me about Zustand'},
+			{
+				role: 'assistant',
+				content:
+					"Zustand is lightweight and simple! It's only 2KB and doesn't need \
+					providers. Here's how to get started...",
+			},
+		],
+	});
+
+	console.log('\nOriginal thread:', originalId);
+	console.log(
+		'Original thread messages:',
+		await langbase.threads.messages.list({threadId: originalId}),
+	);
+	console.log('Branched thread:', branchId);
+	console.log(
+		'Branched thread messages:',
+		await langbase.threads.messages.list({threadId: branchId}),
+	);
+}
+
+main();