Add Gemini API key and update dependencies

.env.example

@@ -1,5 +1,6 @@
 REACT_APP_API_URL=
 OPENAI_API_KEY=
+GEMINI_API_KEY=
 DB_HOST=
 DB_USER=
 DB_PASS=

backend/package.json

@@ -8,10 +8,10 @@
     "start": "node server.js"
   },
   "dependencies": {
+    "@google/generative-ai": "^0.2.1",
     "bcrypt": "^5.1.1",
     "cors": "^2.8.5",
     "express": ">5.0.0-alpha",
-    "faker": "^6.6.6",
     "jsonwebtoken": "^9.0.2",
     "mongodb": "^5.9.2",
     "mongoose": "^8.1.1",

backend/server.js

@@ -1,24 +1,28 @@
 const express = require("express");
 const cors = require("cors");
-const { set } = require("mongoose");
-// const mongoose = require("mongoose");
+const mongoose = require("mongoose");
 // const bcrypt = require("bcrypt");
 // const validator = require("validator");
 // const jwt = require("jsonwebtoken");
+const {
+  GoogleGenerativeAI,
+  HarmCategory,
+  HarmBlockThreshold,
+} = require("@google/generative-ai");
 
 const app = express();
 
 // connect to DB
-// const mongoDB =
-//   "mongodb+srv://" +
-//   process.env.USERNAME +
-//   ":" +
-//   process.env.PASSWORD +
-//   "@" +
-//   process.env.HOST +
-//   "/" +
-//   process.env.DATABASE;
-// mongoose.connect(mongoDB);
+const mongoDB =
+  "mongodb+srv://" +
+  process.env.DB_USER +
+  ":" +
+  process.env.DB_PASS +
+  "@" +
+  process.env.DB_HOST +
+  "/" +
+  process.env.DB_NAME;
+mongoose.connect(mongoDB);
 
 app.use(cors());
 app.use(express.json());
@@ -31,12 +35,53 @@ app.post("/api/chat", async (req, res) => {
   if (!req.body.message) {
     return res.status(400).json({ message: "No message provided" });
   }
-  // add a delay for testing
-  await new Promise((resolve) => setTimeout(resolve, 10000));
 
-  res.status(200).json({
-    message: `[backend] under construction. You sent: ${req.body.message}`,
-  });
+  // node --version # Should be >= 18
+  // npm install @google/generative-ai
+  const MODEL_NAME = "gemini-1.0-pro";
+  const AI_API_KEY = process.env.GEMINI_API_KEY;
+
+  async function runChat() {
+    const genAI = new GoogleGenerativeAI(AI_API_KEY);
+    const model = genAI.getGenerativeModel({ model: MODEL_NAME });
+
+    const generationConfig = {
+      temperature: 0.9,
+      topK: 1,
+      topP: 1,
+      maxOutputTokens: 2048,
+    };
+
+    const safetySettings = [
+      {
+        category: HarmCategory.HARM_CATEGORY_HARASSMENT,
+        threshold: HarmBlockThreshold.BLOCK_ONLY_HIGH,
+      },
+      {
+        category: HarmCategory.HARM_CATEGORY_HATE_SPEECH,
+        threshold: HarmBlockThreshold.BLOCK_ONLY_HIGH,
+      },
+      {
+        category: HarmCategory.HARM_CATEGORY_SEXUALLY_EXPLICIT,
+        threshold: HarmBlockThreshold.BLOCK_ONLY_HIGH,
+      },
+      {
+        category: HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT,
+        threshold: HarmBlockThreshold.BLOCK_ONLY_HIGH,
+      },
+    ];
+
+    const chat = model.startChat({
+      generationConfig,
+      safetySettings,
+      history: req.body.history || [],
+    });
+
+    const result = await chat.sendMessage(req.body.message);
+    const response = result.response;
+    res.status(400).json({ message: response });
+  }
+
   // todo api request via node @link https://platform.openai.com/docs/quickstart?context=node
 });