mongoose-database-schema/src/database.js

MongoDB database documentation generator with table schemas and relationships

const { MongoClient } = require('mongodb');

class DatabaseConnection {
  constructor(connectionString, dbName) {
    this.connectionString = connectionString;
    this.dbName = dbName;
    this.client = null;
    this.db = null;
  }

  async connect() {
    try {
      this.client = new MongoClient(this.connectionString);
      await this.client.connect();
      this.db = this.client.db(this.dbName);
      console.log(`Connected to MongoDB database: ${this.dbName}`);
      return this.db;
    } catch (error) {
      console.error('Database connection failed:', error);
      throw error;
    }
  }

  async disconnect() {
    if (this.client) {
      await this.client.close();
      console.log('Database connection closed');
    }
  }

  async getCollections() {
    if (!this.db) {
      throw new Error('Database not connected');
    }
    
    const collections = await this.db.listCollections().toArray();
    return collections.map(col => col.name);
  }

  async getCollectionStats(collectionName) {
    if (!this.db) {
      throw new Error('Database not connected');
    }
    
    const collectionStats = await this.db.collection(collectionName).stats();
    
    return {
      totalDocuments: collectionStats.count,
      avgDocumentSize: collectionStats.avgObjSize,
      totalSize: collectionStats.size,
      indexCount: collectionStats.nindexes
    };
  }
}

module.exports = DatabaseConnection;