const mongoose = require('mongoose'); const Schema = mongoose.Schema; mongoose.Promise = global.Promise; mongoose.level = "F"; const { ObjectID } = require('mongodb'); // Resolving error Unknown modifier: $pushAll mongoose.plugin(schema => { schema.options.usePushEach = true }); const SubscriberSchema = new Schema({ endpoint: String, keys: Schema.Types.Mixed, userId: String, access: String, browser: String, createDate: { type: Date, default: Date.now } }); mongoose.model('subscribers', SubscriberSchema);