mongo bulk insert

mongo-bulk.js

function updateOrUpsertMany(mongo, col, docs) {
    const bulk = mongo.colection(col).initializeUnorderedBulkOp();
    docs.forEach(doc => {
      bulk.find({ _id: doc._id }).upsert().updateOne({ $set: doc });
    });
    if (docs.length > 0) {
      return bulk.execute()
        .catch((ex) => {
          if (ex.message.indexOf('E11000 duplicate key error collection') !== -1) {
            return this.updateOrUpsertMany(mongo, col, docs);
          }
          throw ex;
        });
    }
    const error = new Error('Noting to insert');
    return Promise.reject(error);
  };