Intercâmbio de dados sem as desvantagens do XML

Douglas Crockford, em seu artigo “JSON: The Fat-Free Alternative to XML”, exibe um comparativo entre os formatos para intercâmbio de dados JSON e XML, mostrando as vantagens da utilização do JSON (JavaScript ObjectNotation).

The most informed opinions on XML (see for example xmlsuck.org) suggest that XML has big problems as a data-interchange format, but the disadvantages are compensated for by the benefits of interoperability and openness.
JSON promises the same benefits of interoperability and openness, but without the disadvantages.

Publicidade

Symfony Cheat-Sheet – Helpers Javascript e Ajax


Continuando a publicação das referências sobre o framework symfony, esta segunda inicia a série sobre os helpers do symfony, trazendo uma visão geral das funções Javascript e Ajax que o framework possui.

Idiomas disponíveis:

  • Português – PDF
  • English – PDF
  • Français – PDF (Traduit par COil. Merci!)

page_word.png For translators (Word document with the cheat-sheet texts)

[Update – 01/01/2008] adicionada tradução para francês

Regras para otimizar a performance de sites web

As 14 regras, segundo Steve Souders (Chief Performance Yahoo!), para otimizar o desempenho de sites web:

  • Rule 1 – Make Fewer HTTP Requests
  • Rule 2 – Use a Content Delivery Network
  • Rule 3 – Add an Expires Header
  • Rule 4 – Gzip Components
  • Rule 5 – Put CSS at the Top
  • Rule 6 – Move Scripts to the Bottom
  • Rule 7 – Avoid CSS Expressions
  • Rule 8 – Make JavaScript and CSS External
  • Rule 9 – Reduce DNS Lookups
  • Rule 10 – Minify JavaScript
  • Rule 11 – Avoid Redirects
  • Rule 12 – Remove Duplicate Scripts
  • Rule 13 – Turn Off ETags
  • Rule 14 – Make AJAX Cacheable and Small

A otimização do Front-End é o fator chave para um alto desempenho:

There are three main reasons why front-end performance is the place to start.

  1. There is more potential for improvement by focusing on the front-end. Cutting it in half reduces response times by 40% or more, whereas cutting back-end performance in half results in less than a 10% reduction.
  2. Front-end improvements typically require less time and resources than back-end projects (redesigning application architecture and code, finding and optimizing critical code paths, adding or modifying hardware, distributing databases, etc.).
  3. Front-end performance tuning has been proven to work. Over fifty teams at Yahoo! have reduced their end-user response times by following our performance best practices, often by 25% or more.

Our performance golden rule is: optimize front-end performance first, that’s where 80% or more of the end-user response time is spent.