feat(backend): Prisma schema, Express routes, audit middleware, error handling

backend/src/index.js

@@ -0,0 +1,67 @@
+const express = require('express');
+const cors = require('cors');
+const helmet = require('helmet');
+const morgan = require('morgan');
+const prisma = require('./lib/prisma');
+const { globalErrorHandler } = require('./middleware/errorHandler');
+
+const experimentsRouter = require('./routes/experiments');
+const animalsRouter = require('./routes/animals');
+const dailyStatusesRouter = require('./routes/dailyStatuses');
+const auditLogsRouter = require('./routes/auditLogs');
+
+const app = express();
+const PORT = process.env.PORT || 3001;
+
+// Security & utility middleware
+app.use(helmet());
+app.use(cors({
+  origin: process.env.CORS_ORIGIN || '*',
+  methods: ['GET', 'POST', 'PUT', 'DELETE', 'OPTIONS'],
+  allowedHeaders: ['Content-Type', 'Authorization'],
+}));
+app.use(express.json({ limit: '1mb' }));
+app.use(morgan(process.env.NODE_ENV === 'production' ? 'combined' : 'dev'));
+
+// Health check
+app.get('/health', (req, res) => {
+  res.json({ status: 'ok', timestamp: new Date().toISOString() });
+});
+
+// API routes
+app.use('/api/experiments', experimentsRouter);
+app.use('/api/animals', animalsRouter);
+app.use('/api/daily-statuses', dailyStatusesRouter);
+app.use('/api/audit-logs', auditLogsRouter);
+
+// 404 handler for unknown routes
+app.use((req, res) => {
+  res.status(404).json({ error: `Route ${req.method} ${req.path} not found` });
+});
+
+// Global error handler (must be last)
+app.use(globalErrorHandler);
+
+async function startServer() {
+  try {
+    await prisma.$connect();
+    console.log('Database connected successfully');
+
+    // Run migrations on startup in production
+    if (process.env.NODE_ENV === 'production') {
+      const { execSync } = require('child_process');
+      execSync('npx prisma migrate deploy', { stdio: 'inherit' });
+    }
+
+    app.listen(PORT, '0.0.0.0', () => {
+      console.log(`Server running on port ${PORT}`);
+    });
+  } catch (err) {
+    console.error('Failed to start server:', err);
+    process.exit(1);
+  }
+}
+
+startServer();
+
+module.exports = app; // export for testing