AOP with FeathersJS

Show a powerful and flexible way to create API services in NodeJS.

Transcript

1. Aspect Oriented Programming with FeathersJS
2. Why Aspect?
3. Why Aspect ... var express = require('express'); var app = express(); app.update('/', function (req, res, next) { if (isLoggedln(req) && isValidate(req)) { getUser(req.params.userId).then(function (user) { if (isAdmin(user) && isCurrent(user)) { updateInfo(req).then(function (info) { if (info.emailme) { sendEmail(user.email, info) } removePassword(user); res.send(info); }) } }); } }); because systems grow
4. @abraao4lves Software Engennier abraaoalves.github.io
5. Inspiration: Functional Programming f(g(x))
6. Continuation–passing style (CPS)
7. Continuation–passing style (CPS) let createUser = validateRequest >> verifyEmail >> db.createUser >> smtpServer.sendEmail >> returnMessage F# Example:
8. (CPS) with NodeJS ?
9. var express = require('express'); var bodyParser = require('body-parser'); var app = express(); app .use(bodyParser.json()) .use(function (req, res, next) { getUser(req.params.userId).then(function(user){ req.body.username = user.name; next() }) }) .use(function (req, res) { res.json(req.body || {message:'No content'}) }) (CPS) with NodeJS! Express - Middlewares
10. var express = require('express'); var bodyParser = require('body-parser'); var app = express(); app .use(bodyParser.json()) .use(function (req, res, next) { getUser(req.params.userId).then(function(user){ req.body.username = user.name; next() }) }) .use(function (req, res) { res.json(req.body || {message:'No content'}) }) (CPS) with NodeJS! Express - Middlewares
11. And ... Aspect Oriented Programming?
12. Aspect Oriented Programming!
14. Get Starter
15. (CPS) with FeathersJS
16. (CPS) with FeathersJS // Register the hooks app.service('users') .before({ find: [isLoggedIn, isAdmin], get: [isLoggedIn, isCurrent], create: hashPassword }) .after(removePasswords) .after({ create: sendEmail });
17. (CPS) with FeathersJS // Register the hooks app.service('users') .before({ find: [isLoggedIn, isAdmin], get: [isLoggedIn, isCurrent], create: hashPassword }) .after(removePasswords) .after({ create: sendEmail });
18. (CPS) with FeathersJS // Register the hooks app.service('users') .before({ find: [isLoggedIn, isAdmin], get: [isLoggedIn, isCurrent], create: hashPassword }) // To all methods .after(removePasswords) .after({ create: sendEmail });
19. DEMO
20. Thanks. @abraao4lves abraaoalves.github.io