mlab-crud/src/base.js

Simple crud router creation for mlab

let errorHandler = require('./utils').errorHandler;
let Router = require('express').Router;
let ObjectID = require("mongodb").ObjectID;

// @TODO: set req body or query to err response

class BaseOperations {
    constructor(_db, _collection) {
        this.db = _db;
        this.collection = _collection;
    }

    getRouter(routerName) {
        let router = new Router();

        router.get('/' + routerName || this.collection, this.getRequest.bind(this));
        router.post('/' + routerName || this.collection, this.postRequest.bind(this));
        router.put('/' + routerName || this.collection, this.putRequest.bind(this));
        router.delete('/' + routerName || this.collection, this.deleteRequest.bind(this));

        return router;
    }

    //<editor-fold desc="Mongo collection methods">
    getEntities(successCallback, errorCallback, query) {
        let entities = this.db.collection(this.collection);
        query = query || {};

        entities
            .find(query)
            .toArray((err, items) => {
                err && errorCallback(err);
                !err && successCallback(items);
            });
    }

    addEntity(entityToAdd, successCallback, errorCallback) {
        let entities = this.db.collection(this.collection);

        entities.insertOne(entityToAdd, (err, item) => {
            err && errorCallback(err);
            !err && successCallback(item);
        });
    }

    //set update query if needed
    updateEntity(entityToUpdate, successCallback, errorCallback) {
        let entities = this.db.collection(this.collection);
        let objectId = ObjectID(entityToUpdate._id);

        delete entityToUpdate._id;
        entities.updateOne({_id: objectId}, {$set: entityToUpdate})
            .then(successCallback);
    }
    //</editor-fold>

    //<editor-fold desc="Requests handlers">
    getRequest(req, resp) {
        let query = req.query.query ? JSON.parse(req.query.query) : {};
        this.getEntities(
            items => resp.send(items),
            err => errorHandler(resp, err), query);
    }

    postRequest(req, resp) {
        let entity = req.body.entity;

        this.addEntity(entity,
            addedItem => resp.send(addedItem.ops[0]),
            err => errorHandler(resp, err));
    }

    putRequest(req, resp) {
        let entity = req.body.entity;

        this.updateEntity(entity,
            addedItem => resp.send(addedItem),
            err => errorHandler(resp, err));
    }

    deleteRequest(req, resp) {
        let entity = req.body.entity;
        let entities = this.db.collection(this.collection);

        entities.deleteOne({_id: ObjectID(entity._id)})
            .then(removedItem => resp.send(removedItem));
    }
    //</editor-fold>
}

module.exports.Base = BaseOperations;