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Merged
rishabhx29 merged 1 commit into from
Jun 29, 2026
Merged

Add centralized environment variable validation during application startup #60

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26 changes: 26 additions & 0 deletions backend/src/config/env.ts
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Original file line number Diff line number Diff line change
@@ -0,0 +1,26 @@
import dotenv from "dotenv";
dotenv.config();

const requiredEnv = [
"PORT",
"MONGO_URI",
"JWT_SECRET",
"GOOGLE_CLIENT_ID",
"CLIENT_URL",
"GEMINI_API_KEY"
]

requiredEnv.forEach((key) => {
if(!process.env[key]) {
throw new Error(`Missing required environment variable: ${key}`);
}
})

export const config = {
PORT: process.env.PORT,
MONGO_URI: process.env.MONGO_URI,
JWT_SECRET: process.env.JWT_SECRET,
GOOGLE_CLIENT_ID: process.env.GOOGLE_CLIENT_ID,
CLIENT_URL: process.env.CLIENT_URL,
GEMINI_API_KEY: process.env.GEMINI_API_KEY
}
Comment on lines +13 to +26

@coderabbitai coderabbitai Bot Jun 28, 2026

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🎯 Functional Correctness | 🟠 Major | ⚡ Quick win

Materialize validated values instead of re-reading raw process.env.

This only checks truthiness, so whitespace-only values still pass startup, and config is rebuilt from raw env strings afterward. That misses the “misconfigured” part of the fail-fast contract. Validate each value once with a helper (for example, reject value.trim() === '') and export those validated results from config.

🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@backend/src/config/env.ts` around lines 13 - 26, The env validation in config
env.ts only checks truthiness, so whitespace-only values can still slip through
and the exported config is rebuilt from raw process.env afterward. Update the
requiredEnv validation flow to validate each value once with a helper that
rejects empty or trim-only strings, then have config export those
validated/materialized values instead of re-reading process.env. Keep the fix
centered around requiredEnv and the config object so the fail-fast behavior is
enforced consistently.

7 changes: 4 additions & 3 deletions backend/src/controllers/authController.ts
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Expand Up @@ -3,12 +3,13 @@ import jwt from 'jsonwebtoken';
import bcrypt from 'bcryptjs';
import { prisma } from '../config/db';
import { OAuth2Client } from 'google-auth-library';
import { config } from '../config/env';

const client = new OAuth2Client(process.env.GOOGLE_CLIENT_ID);
const client = new OAuth2Client(config.GOOGLE_CLIENT_ID);

// Generate JWT
const generateToken = (id: string) => {
return jwt.sign({ id }, process.env.JWT_SECRET!, { expiresIn: '30d' });
return jwt.sign({ id }, config.JWT_SECRET!, { expiresIn: '30d' });
};

// @desc Register new user
Expand Down Expand Up @@ -97,7 +98,7 @@ export const googleAuth = async (req: Request, res: Response) => {
try {
const ticket = await client.verifyIdToken({
idToken: token,
audience: process.env.GOOGLE_CLIENT_ID
audience: config.GOOGLE_CLIENT_ID
});

const payload = ticket.getPayload();
Expand Down
3 changes: 2 additions & 1 deletion backend/src/controllers/chatController.ts
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@@ -1,6 +1,7 @@
import { Request, Response } from 'express';
import { GoogleGenerativeAI } from '@google/generative-ai';
import { prisma } from '../config/db';
import { config } from '../config/env';

const SYSTEM_PROMPT = `You are AlgoBot, a friendly and expert AI tutor for Data Structures & Algorithms on the AlgoForge platform.

Expand All @@ -24,7 +25,7 @@ export const chat = async (req: Request, res: Response) => {
return res.status(400).json({ error: 'Message is required' });
}

const apiKey = process.env.GEMINI_API_KEY;
const apiKey = config.GEMINI_API_KEY;
if (!apiKey) {
return res.status(500).json({ error: 'Gemini API key not configured' });
}
Expand Down
3 changes: 2 additions & 1 deletion backend/src/middleware/authMiddleware.ts
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@@ -1,6 +1,7 @@
import { Request, Response, NextFunction } from 'express';
import jwt from 'jsonwebtoken';
import { prisma } from '../config/db';
import { config } from '../config/env';

interface JwtPayload {
id: string;
Expand All @@ -24,7 +25,7 @@ const protect = async (req: Request, res: Response, next: NextFunction) => {
try {
token = req.headers.authorization.split(' ')[1];

const decoded = jwt.verify(token, process.env.JWT_SECRET!) as JwtPayload;
const decoded = jwt.verify(token, config.JWT_SECRET!) as JwtPayload;

const user = await prisma.user.findUnique({
where: { id: decoded.id },
Expand Down
3 changes: 2 additions & 1 deletion backend/src/scripts/migrate_users.ts
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Original file line number Diff line number Diff line change
@@ -1,10 +1,11 @@
import { PrismaClient } from '@prisma/client';
import dotenv from 'dotenv';
import path from 'path';
import { config } from '../config/env';

dotenv.config({ path: path.join(__dirname, '../../.env') });

const uri = process.env.MONGO_URI as string;
const uri = config.MONGO_URI as string;
Comment on lines +4 to +8

@coderabbitai coderabbitai Bot Jun 28, 2026

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🩺 Stability & Availability | 🟠 Major | 🏗️ Heavy lift

🧩 Analysis chain

🏁 Script executed:

#!/bin/bash
set -euo pipefail

printf '\n== file list ==\n'
git ls-files backend/src/scripts/migrate_users.ts backend/src/config/env.ts

printf '\n== outlines ==\n'
ast-grep outline backend/src/scripts/migrate_users.ts --view expanded || true
ast-grep outline backend/src/config/env.ts --view expanded || true

printf '\n== migrate_users.ts ==\n'
cat -n backend/src/scripts/migrate_users.ts | sed -n '1,120p'

printf '\n== env.ts ==\n'
cat -n backend/src/config/env.ts | sed -n '1,220p'

Repository: Rishabhworkspace/AlgoForge

Length of output: 7399

Load dotenv before importing config.

backend/src/config/env.ts calls dotenv.config() and validates process.env at import time, so the dotenv.config({ path: path.join(__dirname, '../../.env') }) here runs too late to affect config.MONGO_URI. If this script depends on ../../.env, it can fail during module initialization; move dotenv bootstrapping above the config import or let the config module own the path resolution.

🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@backend/src/scripts/migrate_users.ts` around lines 4 - 8, The script
initializes dotenv after importing config, so MONGO_URI is validated before the
.env file is loaded. In migrate_users.ts, move the dotenv bootstrap that uses
path.join(__dirname, '../../.env') ahead of the config import, or rely on env.ts
to load the correct file itself. Make sure the import order in migrate_users.ts
allows config.MONGO_URI to be resolved only after environment variables are
available.


async function migrate() {
console.log("Starting migration using Prisma engine to bypass DNS issues...");
Expand Down
10 changes: 3 additions & 7 deletions backend/src/server.ts
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Expand Up @@ -4,22 +4,18 @@ import cors from 'cors';
import connectDB from './config/db';

dotenv.config();

// server.ts — add before app.listen()
if (!process.env.JWT_SECRET) {
throw new Error('FATAL: JWT_SECRET environment variable is not set.');
}
import { config } from './config/env';

const app: Express = express();
const port = process.env.PORT || 5000;
const port = config.PORT || 5000;

// Middleware
const allowedOrigins = [
'https://algo-forge-2-0.vercel.app',
'https://algoforge-2-0.onrender.com',
'http://localhost:5173',
'http://localhost:3000',
process.env.CLIENT_URL,
config.CLIENT_URL,
].filter(Boolean) as string[];

app.use(cors({
Expand Down
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