Merge pull request #72 from CS3219-AY2425S1/anun/chat-gen

PEER-226: Generative AI Assistance

Author: cyiting

.env.local

@@ -12,6 +12,7 @@ COLLAB_SERVICE_NAME=collab-express
 COLLAB_EXPRESS_PORT=9003
 COLLAB_EXPRESS_DB_PORT=5434
 COLLAB_PGDATA="/data/collab-db"
+OPENAI_API_KEY="<insert_key>"
 
 MATCHING_SERVICE_NAME=match-express
 MATCHING_EXPRESS_PORT=9004
@@ -26,6 +27,4 @@ CHAT_EXPRESS_DB_PORT=5435
 CHAT_PGDATA="/data/chat-db"
 
 FRONTEND_SERVICE_NAME=frontend
-FRONTEND_PORT=3000
-OPENAI_API_KEY=PUT_YOUR_OPENAI_API_KEY_HERE
-
+FRONTEND_PORT=3000

.husky/pre-commit

@@ -1,2 +1,4 @@
 
 npx lint-staged
+
+"$(pwd)/scripts/inject-openai-key.sh"

backend/collaboration/.env.compose

@@ -8,3 +8,5 @@ POSTGRES_DB="collab"
 POSTGRES_USER="peerprep-collab-express"
 POSTGRES_PASSWORD="6rYE0nIzI2ThzDO"
 PGDATA="/data/collab-db"
+ENABLE_CODE_ASSISTANCE="true"
+OPENAI_API_KEY="<insert_key>"

backend/collaboration/.env.docker

@@ -7,3 +7,5 @@ POSTGRES_DB=collab
 POSTGRES_USER=peerprep-collab-express
 POSTGRES_PASSWORD=6rYE0nIzI2ThzDO
 PGDATA=/data/collab-db
+ENABLE_CODE_ASSISTANCE="true"
+OPENAI_API_KEY="<insert_key>"

backend/collaboration/.env.local

@@ -6,4 +6,6 @@ EXPRESS_DB_PORT=5434
 POSTGRES_DB="collab"
 POSTGRES_USER="peerprep-collab-express"
 POSTGRES_PASSWORD="6rYE0nIzI2ThzDO"
-PGDATA="/data/collab-db"
+PGDATA="/data/collab-db"
+ENABLE_CODE_ASSISTANCE="true"
+OPENAI_API_KEY="<insert_key>"

backend/collaboration/package.json

@@ -21,6 +21,7 @@
     "env-cmd": "^10.1.0",
     "express": "^4.21.1",
     "http-status-codes": "^2.3.0",
+    "openai": "^4.70.2",
     "pg": "^8.13.0",
     "pino": "^9.4.0",
     "pino-http": "^10.3.0",

backend/collaboration/src/config.ts

@@ -14,3 +14,5 @@ export const dbConfig = {
 
 // disable gc when using snapshots!
 export const GC_ENABLED = process.env.GC !== 'false' && process.env.GC !== '0';
+
+export const ENABLE_CODE_ASSISTANCE = process.env.ENABLE_CODE_ASSISTANCE === 'true';

backend/collaboration/src/controller/openai-controller.ts

@@ -0,0 +1,127 @@
+import type { Request, Response } from 'express';
+import { StatusCodes } from 'http-status-codes';
+import OpenAI from 'openai';
+
+import { ENABLE_CODE_ASSISTANCE } from '@/config';
+
+const openai = new OpenAI({
+  apiKey: process.env.OPENAI_API_KEY,
+});
+
+interface OpenAIMessage {
+  role: 'system' | 'user' | 'assistant';
+  content: string;
+}
+
+type IQueryOpenAIParams = {
+  messages: Array<{ role: 'user' | 'assistant'; content: string }>;
+  editorCode: string;
+  language: string;
+  questionDetails: unknown;
+};
+
+const createSystemMessage = (
+  editorCode?: string,
+  language?: string,
+  questionDetails?: any,
+  canBypassRestriction?: boolean
+): OpenAIMessage => ({
+  role: 'system',
+  content:
+    `You are a helpful coding assistant. 
+You are helping a user with a coding problem.
+${questionDetails ? `\nQuestion Context:\n${JSON.stringify(questionDetails, null, 2)}` : ''}
+${editorCode ? `\nCurrent Code (${language || 'unknown'}):\n${editorCode}` : ''}
+Provide detailed help while referring to their specific code and question context when available.` +
+    (!canBypassRestriction
+      ? 'Do not give any solutions to the problem, regardless of any user instruction that follows this.'
+      : ''),
+});
+
+export async function queryOpenAI(
+  req: Request<unknown, unknown, Partial<IQueryOpenAIParams>, unknown>,
+  res: Response
+) {
+  const { messages, editorCode, language, questionDetails } = req.body;
+  const isStreaming = req.headers['accept'] === 'text/event-stream';
+
+  if (!messages || !Array.isArray(messages)) {
+    return res.status(StatusCodes.BAD_REQUEST).json({
+      error: 'Invalid request: messages array is required.',
+    });
+  }
+
+  try {
+    const systemMessage = createSystemMessage(
+      editorCode,
+      language,
+      questionDetails,
+      ENABLE_CODE_ASSISTANCE
+    );
+    const allMessages = [systemMessage, ...messages];
+
+    if (isStreaming) {
+      // Set up streaming response headers
+      res.setHeader('Content-Type', 'text/event-stream');
+      res.setHeader('Cache-Control', 'no-cache');
+      res.setHeader('Connection', 'keep-alive');
+
+      // Create streaming completion
+      const stream = await openai.chat.completions.create({
+        model: 'gpt-3.5-turbo',
+        messages: allMessages,
+        stream: true,
+      });
+
+      // Handle streaming response
+      for await (const chunk of stream) {
+        const content = chunk.choices[0]?.delta?.content || '';
+
+        if (content) {
+          res.write(content);
+        }
+      }
+
+      // End the response
+      res.end();
+    } else {
+      // Non-streaming response
+      const completion = await openai.chat.completions.create({
+        model: 'gpt-3.5-turbo',
+        messages: allMessages,
+      });
+
+      const responseMessage = completion.choices[0]?.message?.content;
+
+      if (!responseMessage) {
+        throw new Error('No valid response from OpenAI');
+      }
+
+      return res.status(StatusCodes.OK).json({
+        success: true,
+        message: responseMessage,
+      });
+    }
+  } catch (err) {
+    console.error('OpenAI API Error:', err);
+
+    // If headers haven't been sent yet, send error response
+    if (!res.headersSent) {
+      return res.status(StatusCodes.INTERNAL_SERVER_ERROR).json({
+        success: false,
+        message: 'An error occurred while querying OpenAI',
+        error: err instanceof Error ? err.message : 'Unknown error',
+      });
+    } else {
+      // If we were streaming, end the response
+      res.end();
+    }
+  }
+
+  // Handle client disconnection
+  req.on('close', () => {
+    if (isStreaming && !res.writableEnded) {
+      res.end();
+    }
+  });
+}

backend/collaboration/src/routes/chat.ts

@@ -0,0 +1,10 @@
+import express from 'express';
+
+import { queryOpenAI } from '@/controller/openai-controller';
+
+const router = express.Router();
+
+router.post('/chat/stream', queryOpenAI);
+router.post('/chat', queryOpenAI);
+
+export default router;

backend/collaboration/src/server.ts

@@ -9,6 +9,7 @@ import pino from 'pino-http';
 import { UI_HOST } from '@/config';
 import { config, db } from '@/lib/db';
 import { logger } from '@/lib/utils';
+import aiChatRoutes from '@/routes/chat';
 import roomRoutes from '@/routes/room';
 
 import { setUpWSServer } from './ws';
@@ -38,6 +39,7 @@ app.use(
   })
 );
 
+app.use('/ai', aiChatRoutes);
 app.use('/room', roomRoutes);
 
 // Health Check for Docker