mongoConnection.ts

import {
  MongoClientOptions,
  MongoClient,
  Db,
  FilterQuery,
  FindOneOptions,
  OptionalId,
  CollectionInsertOneOptions,
  FindOneAndUpdateOption,
  UpdateQuery,
  CommonOptions
} from "mongodb";

let connection: MongoClient | null = null;
let db: Db | null = null;

export async function createConnectionInstance() {
  const uri = process.env.uri
  const connection = await MongoClient.connect(uri, {
    useNewUrlParser: true,
    poolSize: 10,
    useUnifiedTopology: true
  });

  return connection;
}

export async function getDatabase() {
  if (db) {
    return db;
  }

  connection = await createConnectionInstance();

  const name = getConfig<string>("mongo.name");

  db = connection.db(name);

  return db;
}

export async function getCollection<T>(collection: string) {
  const db = await getDatabase();
  return db.collection<T>(collection);
}

export async function find<T>(
  collectionName: string,
  query?: FilterQuery<T>,
  options?: FindOneOptions<T extends T ? T : T>
) {
  const collection = await getCollection<T>(collectionName);
  return collection.find(query || {}, options);
}

export async function findOne<T>(
  collectionName: string,
  query?: FilterQuery<T>,
  options?: FindOneOptions<T extends T ? T : T>
) {
  const collection = await getCollection<T>(collectionName);
  return collection.findOne(query || {}, options);
}

export async function count<T>(collectionName: string) {
  const collection = await getCollection<T>(collectionName);
  return collection.count();
}

export async function insertOne<T>(
  collectionName: string,
  payload: OptionalId<T>,
  options?: CollectionInsertOneOptions
) {
  const collection = await getCollection<T>(collectionName);
  return collection.insertOne(payload, options);
}

export async function findOneAndUpdate<T>(
  collectionName: string,
  filter: FilterQuery<T>,
  payload: UpdateQuery<T> | T,
  options?: FindOneAndUpdateOption<T>
) {
  const collection = await getCollection<T>(collectionName);
  return collection.findOneAndUpdate(filter, payload, options);
}

export async function deleteOne<T>(
  collectionName: string,
  filter: FilterQuery<T>,
  options?: CommonOptions & { bypassDocumentValidation?: boolean }
) {
  const collection = await getCollection<T>(collectionName);
  return collection.deleteOne(filter, options);
}