mongo.js

// this is a helper utility class to help with mongodb queries and operations

// function to connect to mongodb and disconnect
const MongoClient = require('mongodb').MongoClient;

// change connect close to as required
// connect to mongodb on every call and connection details from env variables
const connect = async () => {
  const client = await MongoClient.connect(process.env.MONGO_URL, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
  });
  const mongodb = client.db(process.env.MONGO_DB);
  return mongodb;
};

// function to create entry in mongodb and return whole object with id
const insertOne = async (mongodb, collection, data) => {
  const result = await mongodb.collection(collection).insertOne(data);

  return result.insertedId;
};

// function to search entry in mongodb with filteration and pagination with default values to return all pages
const find = async (mongodb, collection, filter, page = 1, limit = 10) => {
  const result = await mongodb.collection(collection).find(filter).skip((page - 1) * limit).limit(limit).toArray();

  return result;
};

// function to search entry in mongodb with filteration without pagination
const findOne = async (mongodb, collection, filter) => {
  const result = await mongodb.collection(collection).findOne(filter);

  return result;
};

// function to fetch all entries in a collection
const findAll = async (mongodb, collection) => {
  const result = await mongodb.collection(collection).find().toArray();

  return result;
};

// function to find and update an entry
const findAndUpdate = async (mongodb, collection, filter, data) => {
  const result = await mongodb.collection(collection).findOneAndUpdate(filter, { $set: data }, { returnOriginal: false });

  return result.value;
};

// function for findOneAndDelete
const findOneAndDelete = async (mongodb, collection, filter) => {
  const result = await mongodb.collection(collection).findOneAndDelete(filter);

  return result.value;
};

// function for findOneAndUpdate
const findOneAndUpdate = async (mongodb, collection, filter, data) => {
  const result = await mongodb.collection(collection).findOneAndUpdate(filter, { $set: data }, { returnOriginal: false });

  return result.value;
};

// function to update an entry in mongodb with filteration
const update = async (mongodb, collection, filter, data) => {
  const result = await mongodb.collection(collection).updateOne(filter, { $set: data });

  return result.modifiedCount;
};

// function to update all entries if condition matches in a collection
const updateAll = async (mongodb, collection, filter, data) => {
  const result = await mongodb.collection(collection).updateMany(filter, { $set: data });

  return result.modifiedCount;
};

// function for deleteOne in mongodb
const deleteOne = async (mongodb, collection, filter) => {
  const result = await mongodb.collection(collection).deleteOne(filter);

  return result.deletedCount;
};

// function for deleteMany in mongodb
const deleteMany = async (mongodb, collection, filter) => {
  const result = await mongodb.collection(collection).deleteMany(filter);

  return result.deletedCount;
};

// function to count the number of entries in a collection
const count = async (mongodb, collection, filter) => {
  const result = await mongodb.collection(collection).countDocuments(filter);

  return result;
};

// function to clount all entries in a collection
const countAll = async (mongodb, collection) => {
  const result = await mongodb.collection(collection).countDocuments();

  return result;
};

// function to create a collection in db
const createCollection = async (mongodb, collection) => {
  const result = await mongodb.createCollection(collection);

  return result;
}

// function to list all collections in db
const listCollections = async (mongodb,) => {
  const result = await mongodb.listCollections().toArray();

  return result;
}

// function to drop a collection in db
const dropCollection = async (mongodb, collection) => {
  const result = await mongodb.collection(collection).drop();

  return result;
};

module.exports = {
  connect,
  insertOne,
  find,
  findOne,
  findAll,
  findAndUpdate,
  findOneAndDelete,
  findOneAndUpdate,
  update,
  updateAll,
  deleteOne,
  deleteMany,
  count,
  countAll,
  createCollection,
  listCollections,
  dropCollection,
};