feat: add algolia to cohere chat demo

packages/ui/docs-bundle/package.json

@@ -50,6 +50,7 @@
     "@fern-ui/ui": "workspace:*",
     "@sentry/nextjs": "^7.112.2",
     "@vercel/edge-config": "^1.1.0",
+    "@vercel/kv": "^2.0.0",
     "@workos-inc/node": "^6.1.0",
     "cohere-ai": "^7.9.5",
     "cssnano": "^6.0.3",
@@ -65,7 +66,8 @@
     "react-dom": "^18.2.0",
     "sharp": "^0.33.3",
     "ts-essentials": "^10.0.1",
-    "url-join": "5.0.0"
+    "url-join": "5.0.0",
+    "uuid": "^9.0.0"
   },
   "devDependencies": {
     "@fern-platform/configs": "workspace:*",
@@ -76,6 +78,7 @@
     "@types/node-fetch": "2.6.9",
     "@types/react": "^18.0.20",
     "@types/react-dom": "^18.2.18",
+    "@types/uuid": "^9.0.1",
     "autoprefixer": "^10.4.16",
     "depcheck": "^1.4.3",
     "env-cmd": "toddbluhm/env-cmd",

packages/ui/docs-bundle/src/pages/api/fern-docs/search/cohere.ts

@@ -1,11 +1,13 @@
+import { FdrClient } from "@fern-api/fdr-sdk";
+import { kv } from "@vercel/kv";
 import { Cohere, CohereClient } from "cohere-ai";
+import { ChatMessage } from "cohere-ai/api";
+import { NextRequest } from "next/server";
+import { v4 } from "uuid";
+import { getXFernHostEdge } from "../../../../utils/xFernHost";
 
 export const runtime = "edge";
 
-const cohere = new CohereClient({
-    token: process.env.COHERE_API_KEY,
-});
-
 const PREAMBLE = `
 You are an expert AI assistant called Fernie that helps developers answer questions about Cohere's APIs and SDKs.
 The user asking questions is a developer, technical writer, or product manager. Your tone is friendly and helpful, and you can provide code snippets.
@@ -26,19 +28,49 @@ export default async function handler(req: Request): Promise<Response> {
         return new Response(null, { status: 405 });
     }
 
+    const cohere = new CohereClient({
+        token: process.env.COHERE_API_KEY,
+    });
+
+    const docsUrl = getXFernHostEdge(req as NextRequest);
+
     const body = await req.json();
 
+    let conversationId = body.conversationId;
+
+    if (!body.conversationId) {
+        conversationId = v4();
+    }
+
+    const frc = new FdrClient();
+
+    const docsUrlResponse = await frc.docs.v2.read.getDocsForUrl({ url: docsUrl });
+
+    const docsSearchHits = docsUrlResponse.ok ? docsUrlResponse.body.definition.pages : {};
+
+    const transformedDocuments = docsSearchHits
+        ? Object.entries(docsSearchHits).map(([title, text]) => {
+              return { title, text: text.markdown };
+          })
+        : [];
+
+    const chatHistory = (await kv.get<ChatMessage[]>(conversationId)) ?? [];
     const response = await cohere.chatStream({
         preamble: PREAMBLE,
-        conversationId: body.conversationId,
+        chatHistory,
         message: body.message,
+        documents: transformedDocuments.slice(0, 20),
     });
 
-    const stream = convertAsyncIterableToStream(response).pipeThrough(getCohereStreamTransformer());
+    chatHistory.push({ role: "USER", message: body.message });
+
+    const stream = convertAsyncIterableToStream(response).pipeThrough(
+        getCohereStreamTransformer(conversationId, chatHistory),
+    );
 
     return new Response(stream, {
         status: 200,
-        headers: { "Content-Type": "text/plain; charset=utf-8" },
+        headers: { "Content-Type": "text/plain; charset=utf-8", "X-Conversation-Id": conversationId },
     });
 }
 
@@ -53,13 +85,30 @@ function convertAsyncIterableToStream<T>(iterable: AsyncIterable<T>): ReadableSt
     });
 }
 
-function getCohereStreamTransformer() {
+function getCohereStreamTransformer(
+    conversationId: string,
+    chatHistory: ChatMessage[],
+): TransformStream<Cohere.StreamedChatResponse, Uint8Array> {
     const encoder = new TextEncoder();
+    let reply: string = "";
     return new TransformStream<Cohere.StreamedChatResponse, Uint8Array>({
         async transform(chunk, controller) {
             if (chunk.eventType === "text-generation") {
+                reply += chunk.text;
                 controller.enqueue(encoder.encode(chunk.text));
             }
+            if (chunk.eventType === "citation-generation") {
+                // might want to use this somewhere?
+                // console.log(chunk.citations);
+            }
+            if (chunk.eventType === "stream-end") {
+                // not sure what magic number is appropriate here
+                while (chatHistory.length >= 10) {
+                    chatHistory.shift();
+                }
+                chatHistory.push({ role: "CHATBOT", message: reply });
+                await kv.set(conversationId, chatHistory);
+            }
         },
     });
 }