замечания 3

server/routers/procurement/config/db.js

@@ -1,31 +1,97 @@
 const mongoose = require('mongoose');
 
-const connectDB = async () => {
-  try {
-    const mongoUri = process.env.MONGODB_URI || 'mongodb://admin:password@localhost:27017/procurement_db?authSource=admin';
-    
-    console.log('\n📡 Попытка подключения к MongoDB...');
-    console.log(`   URI: ${mongoUri.replace(/\/\/:.*@/, '//***:***@')}`);
-    
-    const connection = await mongoose.connect(mongoUri, {
-      useNewUrlParser: true,
-      useUnifiedTopology: true,
-      serverSelectionTimeoutMS: 5000,
-      connectTimeoutMS: 5000,
-    });
-    
-    console.log('✅ MongoDB подключена успешно!');
-    console.log(`   Хост: ${connection.connection.host}`);
-    console.log(`   БД: ${connection.connection.name}\n`);
-    
-    return connection;
-  } catch (error) {
-    console.error('\n❌ Ошибка подключения к MongoDB:');
-    console.error(`   ${error.message}\n`);
-    console.warn('⚠️  Приложение продолжит работу с mock данными\n');
-    
-    return null;
+// Get MongoDB URL from environment variables
+// MONGO_ADDR is a centralized env variable from server/utils/const.ts
+const primaryUri = process.env.MONGO_ADDR || process.env.MONGODB_URI || 'mongodb://localhost:27017/procurement_db';
+const fallbackUri = process.env.MONGODB_AUTH_URI || 'mongodb://admin:password@localhost:27017/procurement_db?authSource=admin';
+
+/**
+ * Check if error is related to authentication
+ */
+const isAuthError = (error) => {
+  if (!error) {
+    return false;
   }
+
+  const authCodes = new Set([18, 13]);
+  if (error.code && authCodes.has(error.code)) {
+    return true;
+  }
+
+  const message = String(error.message || '').toLowerCase();
+  return message.includes('auth') || message.includes('authentication');
+};
+
+/**
+ * Try to connect to MongoDB with specific URI
+ */
+const connectWithUri = async (uri, label) => {
+  console.log(`\n📡 Попытка подключения к MongoDB (${label})...`);
+  if (process.env.DEV === 'true') {
+    console.log(`   URI: ${uri}`);
+  }
+
+  const connection = await mongoose.connect(uri, {
+    useNewUrlParser: true,
+    useUnifiedTopology: true,
+    serverSelectionTimeoutMS: 5000,
+    connectTimeoutMS: 5000,
+  });
+
+  try {
+    await connection.connection.db.admin().command({ ping: 1 });
+  } catch (pingError) {
+    if (isAuthError(pingError)) {
+      await mongoose.connection.close().catch(() => {});
+      throw pingError;
+    }
+    console.error('⚠️  MongoDB ping error:', pingError.message);
+  }
+
+  console.log('✅ MongoDB подключена успешно!');
+  console.log(`   Хост: ${connection.connection.host}`);
+  console.log(`   БД: ${connection.connection.name}\n`);
+  if (process.env.DEV === 'true') {
+    console.log(`   Пользователь: ${connection.connection.user || 'anonymous'}`);
+  }
+
+  return connection;
+};
+
+/**
+ * Connect to MongoDB with fallback strategy
+ */
+const connectDB = async () => {
+  const attempts = [];
+
+  if (fallbackUri) {
+    attempts.push({ uri: fallbackUri, label: 'AUTH' });
+  }
+
+  attempts.push({ uri: primaryUri, label: 'PRIMARY' });
+
+  let lastError = null;
+
+  for (const attempt of attempts) {
+    try {
+      console.log(`[MongoDB] Trying ${attempt.label} connection...`);
+      return await connectWithUri(attempt.uri, attempt.label);
+    } catch (error) {
+      lastError = error;
+      console.error(`\n❌ Ошибка подключения к MongoDB (${attempt.label}):`);
+      console.error(`   ${error.message}\n`);
+
+      if (!isAuthError(error)) {
+        break;
+      }
+    }
+  }
+
+  if (lastError) {
+    console.warn('⚠️  Приложение продолжит работу с mock данными\n');
+  }
+
+  return null;
 };
 
 module.exports = connectDB;