archivemongo/app.js

Module to archive mongo collections

const { MongoClient } = require('mongodb'),
      assert          = require('assert'),
      { promisify }   = require('util'),
      MongoConnect	  = promisify(MongoClient.connect);

module.exports = {
	ArchieveData : function(mongoDetails, callback){

		if(!mongoDetails.mongoDatabaseUrl || !mongoDetails.archiveCollectionName || !mongoDetails.mainCollectionName){
			throw new Error("Please provide mongoDatabaseUrl, archiveCollectionName and mainCollectionName as an object like { mongoDatabaseUrl : mongoDatabaseUrl, archiveCollectionName : archiveCollectionName, mainCollectionName : mainCollectionName}")
		}else{
			MongoConnect(mongoDetails.mongoDatabaseUrl, { useNewUrlParser: true })
					.then(db => {
						const CreateCollection = promisify(db.createCollection);
						CreateCollection(mongoDetails.archiveCollectionName)
							.then(archive_collection => { CreateCollection(mongoDetails.mainCollectionName) })
							.then(main_collection => {
							      let cursor = main_collection.find({});
							      if(cursor.hasNext()){
									const CursorNext = promisify(cursor.nextObject);
									CursorNext()
										.then(item => {
											const InsertInArchiveCollection = promisify(archive_collection.insert);
												  InsertInArchiveCollection(item)
												  	.then(() => {console.log("DOC INSERTED IN ARCHIVE COLLECTION")});
										})
							      }else{
							      	console.log("ALL ARCHIVED");
							      	callback(null, "ALL ARCHIVED");
							      }
							})
					})
					.catch(err=>{
						throw new Error(err);
					})
		}


	}
} 

module.exports.ArchieveData(mongoDetails, function(err, done){
	if(err){
		console.log("Err is : ", err);
	}else{
		console.log("Done is : ", done)
	}
})