mongodb client wrapper

mongodb.js

// CRUD operator

const mongodb = require("mongodb");

class dbClient {
  constructor() {
    this.MongoClient = mongodb.MongoClient;
    this.connectionURL = "";
    this.client = undefined;
    this.error = undefined;
    this.database = undefined;
  }
  connect(connectionURL) {
    return new Promise(async (resolve, reject) => {
      try {
        this.client = await this.MongoClient.connect(this.connectionURL, {
          useNewUrlParser: true
        });
        this.connectURL = connectionURL;
        resolve(this.client);
      } catch (error) {
        this.error = {
          message: "connection error to mongodb client. try again later.",
          code: 500,
          error
        };
        this.client = undefined;
        reject(this.error);
      }
    });
  }
  setDatabase(databaseName) {
    if (this.error) {
      console.error(this.error);
      this.database = undefined;
      return;
    } else if (!this.client) {
      this.error = {
        message: "client not found.",
        code: 500
      };
      this.database = undefined;
      return;
    } else {
      this.database = this.client.db(databaseName);
    }
  }
  getDatabase() {
    return this.database;
  }
  createOne(collectionName, doc, callback) {
    if (this.error) {
      console.error(this.error);
      return;
    } else if (!this.database) {
      this.error = {
        message: "database not found.",
        code: 500
      };
    } else {
      this.database
        .collection(collectionName)
        .insertOne(doc, (error, result) => {
          callback(error, result);
        });
    }
  }
  createMany(collectionName, arrayDoc, callback) {
    if (this.error) {
      console.error(this.error);
      return;
    } else if (!this.database) {
      this.error = {
        message: "database not found.",
        code: 500
      };
      return;
    } else {
      this.database
        .collection(collectionName)
        .insertMany(arrayDoc, (error, result) => {
          callback(error, result);
        });
    }
  }
  readOne(collectionName, query, callback) {}
  updateOne(collectionName, query, doc, callback) {}
  deleteOne(collectionName, query, callback) {}
}

const connectionURL = "mongodb://127.0.0.1:27018";

const bot = new dbClient();
bot
  .connect(connectionURL)
  .then(client => {
    client.setDatabase("task-manager");
    client.createMany(
      "tasks",
      [
        { description: "End badminton membership", completed: false },
        { description: "Read bible 5 chapters", completed: false },
        { description: "Go to friday service", completed: false }
      ],
      (error, result) => {
        if (error) {
          console.log(error);
        } else {
          console.log(
            "successfully added three documents to tasks collection on task-manager db!"
          );
        }
      }
    );
  })
  .catch(e => {
    console.log(e);
  });

module.exports = dbClient;

/** log **/
/*
{
  message: 'connection error to mongodb client. try again later.',
  code: 500,
  error: MongoParseError: Invalid connection string
      at parseConnectionString (/Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/node_modules/mongodb-core/lib/uri_parser.js:505:21)
      at connect (/Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/node_modules/mongodb/lib/operations/mongo_client_ops.js:195:3)
      at connectOp (/Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/node_modules/mongodb/lib/operations/mongo_client_ops.js:284:3)
      at /Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/node_modules/mongodb/lib/utils.js:433:24
      at new Promise (<anonymous>)
      at executeOperation (/Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/node_modules/mongodb/lib/utils.js:428:10)
      at MongoClient.connect (/Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/node_modules/mongodb/lib/mongo_client.js:175:10)
      at Function.MongoClient.connect (/Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/node_modules/mongodb/lib/mongo_client.js:341:22)
      at /Users/myroot/Note/Node/The-Complete-Node.js-Developer-Course-3rd-Edition/node-course/task-manager/mongodb.js:16:46
      at new Promise (<anonymous>) {
    name: 'MongoParseError',
    [Symbol(mongoErrorContextSymbol)]: {}
  }
}
*/