Entities on Node.jsEntities on Node.js

/thanpolas/entity/thanpolas/entity

Entities useEntities useCIP

for Classical Inheritance /thanpolas/cip

Bluebirdfor the 100% Promises API /petkaantonov/bluebird

Middlewarifyfor creating middleware /thanpolas/middlewarify

Entities extendEntities extendevents.EventEmitter

...and that's the only thing they do

Creating an EntityCreating an Entity

var entity = require('entity');

var EntityChild = entity.extend(function() { this.a = 1;});

var EntityGrandChild = EntityChild.extend();

entity.extend

var entity = require('entity');

var UserEntity = entity.extendSingleton(function() {});

/* ... */

var userEnt = UserEntity.getInstance();

entity.extendSingleton

Entities AdaptorsEntities AdaptorsMongooseMongoose

MongoDB ORMhttp://mongoosejs.com/

SequelizeSequelizePostgreSQLMySQLMariaDBSQLitehttp://sequelizejs.com/

CRUD PrimitivesCRUD Primitivescreate(data)

read(query=)

readOne(query)

readLimit(?query, offset, limit)

update(query, updateValues)

delete(query)

count(query=)

CRUD PrimitivesCRUD Primitivescreate()create()

entity.create({name: 'thanasis'}) .then(function(udo) { udo.name === 'thanasis'; // true }) .catch(function(error) { // deal with error. });

... so on and so forth ...

Entity HooksEntity HooksMiddlewarify in action

beforeafterlast

Entity HooksEntity Hooksbeforebefore

// a middleware with synchronous resolutionentity.read.before(function(data){ if (!data.name) { throw new TypeError('No go my friend'); }});

// then...entity.read({}).then(function(document) { // you'll never get here}, function(err) { err instanceof Error; // true err.message === 'No go my friend'; // true});

Hooks are FiFoHooks are FiFoOrder MATTERSOrder MATTERS

Hooks areHooks areMiddlewareMiddleware

Before HooksBefore HooksGet the exact same number or arguments

After & Last HooksAfter & Last HooksGets the result plus the original number or arguments

Entity HooksEntity HooksAsynchronicityAsynchronicity

entity.create.before(function(data){ return promiseReturningFn(function(result) { resolve(result + 1); });});

Extending EntitiesExtending Entitiesadding new methodsadding new methods

Extending EntitiesExtending EntitiesJust use the prototypeJust use the prototype

var Entity = require('entity');

var UserEntity = module.exports = Entity.extend();

UserEntity.prototype.report = function(userId) { return promiseReturningAction(userId);};

Extending EntitiesExtending EntitiesUsing method()Using method()

var Entity = require('entity');

var UserEntity = module.exports = Entity.extend(function() { this.method('report', this._report.bind(this));

this.report.before(this._checkUserId.bind(this)); this.report.after(this._normalize.bind(this));});

UserEntity.prototype._report = function(userId) { return promiseReturningAction(userId);};

Let's combine all upLet's combine all up

var ClipEntity = module.exports = EntityBase.extendSingleton(function() { this.setModel(clipModel.Model);

this.method('readOneApi', this.readOne); this.method('readLimitApi', this.readLimit); this.method('updateApi', this.update); this.method('readApi', this.read);

// Apply system wide (global) filters this.readLimitApi.before(this.systemFilter.bind(this)); this.readOneApi.before(this.systemFilter.bind(this));

// Clip Creation middleware this.create.before(this._populateActiveEvent.bind(this)); this.create.after(this._processNewClip.bind(this));

// Record sanitization middleware this.updateApi.after(helpers.skipArgs(this.sanitizeResult, 2, this)); this.readLimitApi.after(helpers.skipArgs(this.sanitizeResults, 3, this)); this.readOneApi.after(helpers.skipArgs(this.sanitizeResult, 1, this));});

A Production-ish EntityA Production-ish Entity

Entity Hands OnEntity Hands Onthis.readLimitApi.before(this.systemFilter.bind(this));

/** * Apply system filters in all incoming READ queries * to exclude deleted and corrupt items. * * @param {Object} query The query. */ClipEntity.prototype.systemFilter = function(query) { query.notFound = { ne: true }; query.processed = true;};

Entity Hands OnEntity Hands Onthis.create.after(this._processNewClip.bind(this));

/** * Post creation clip processing. * * @param {Object} data Item used to create the record. * @param {app.entity.ClipProcess} processEnt The process entity. * @param {mongoose.Document} clipItem The result. * @return {Promise} A promise. * @private */ClipEntity.prototype._processNewClip = Promise.method(function(data, processEnt, clipItem) { processEnt.clipId = clipItem.id; log.finest('_processNewClip() :: Clip Saved to DB, starting FS save...', clipItem.id);

return this._checkWatermarkAndStore(processEnt, clipItem) .bind(processEnt) .then(processEnt.createThumbnail) .then(processEnt.checkS3) .then(processEnt.updateDatabase) .then(function() { log.fine('_processNewClip() :: Clip processing finished:', processEnt.sourceFilePath); }) .catch(processEnt.moveToTrash) .catch(processEnt._deleteRecord);});

Now let's get crazyNow let's get crazy

EntitiesEntities

++CrudeCrude

POST /userGET /userGET /user/:idPUT /user/:idPATCH /user/:idDELETE /user/:id

/thanpolas/crude

... but not today... but not today

Thank you(here is where you applaud)

Thanasis Polychronakis@thanpolashttp://www.slideshare.net/thanpolas

Questions?Be a critic

Thanasis Polychronakis@thanpolashttp://www.slideshare.net/thanpolas

Shameless Plug Time

Promo Codebgwebsummit

From 60€ --> 40€

15/5/2015@ Thessaloniki Greecedevitconf.org

Questions?

Thanasis Polychronakis@thanpolas