Commons - MongoDB

Contents

1. Connection
2. CRUD Operations

Connection

To connect to the mongo database call connectToServer method and pass in uri and custom database options.

This will return 2 parameters status and message. If status is true that means you are connected.

const { connections: mongoConn } = require('commons-mongodb-crud')

const res = await mongoConn.connectToServer("mongodb://localhost", {})

console.log(res)
// { status: true, message: 'Connected MongoDB: my_db' }

Re-use same connection elsewhere

Once connected you get status flag. Now you can utilize the same connection anywhere in your node.js application.

To do so use getDb() function to get the connection.

const { connections: mongoConn } = require('commons-mongodb-crud')

const connectionObj = mongoConn.getDb()
// further use connectionObj to run any query

Close database connection on app shutdown

This is important part of the connection. Use closeConnections() method if there is no requirement of using mysql connection or during graceful shutdown

const { connections: mongoConn } = require('commons-mongodb-crud')

mongoConn.closeConnections()

Crud Operations

Running Simple query

To run a query against the given database use runQuery() method of mysqlCrud

• collection: This can be your collection name which can be passed in the form of string
• query: This is an object which is used to narrow down the collection data
• projection: In order to get only the required fields in response the projection object can be passed

const { crud } = require('commons-mongodb-crud')

const findRes = await crud.find(collection, query, projection, options)
// options: To customize the documents options is used. Currently the below options are supported
// const options = { limit: 10, page: 1, sort: "firstName", order: "asc" | "desc" }

const findOneRes = await crud.findOne(collection, query, projection)

const insertOneRes = await crud.insertOne(collection, data)
// data: The data is a document you want to store in the given collection

const updateOneRes = await crud.updateOne(collection, query, set)
// set: pass in set object that you want to update in the existing document
// The parameters that are passed in the set value will be updated

const deleteOneRes = await crud.deleteOne(collection, query)